Effects of production systems and canola meal supplementation on carcass and meat quality characteristics of spent laying hens
- Authors: Semwogerere, Farouk
- Date: 2018
- Subjects: Broilers (Chickens) -- Feeding and feeds Chickens -- Feeding and feeds Chicken industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9242 , vital:34309
- Description: This study evaluated the carcass and meat quality traits of spent laying hens as influenced by production systems (conventional cages and free range) and the inclusion/exclusion of canola meal in their diets. A total of 30 free range and 60 battery cage reared Lohmann Brown-Elite spent laying hens were obtained from a commercial egg producer. The 30 free range hens (53 weeks of age) and 30 of the caged hens (40 weeks of age) were fed a conventional diet, while the remaining 30 caged hens (48 weeks of age) were fed a diet supplemented with canola meal (20 percent). Carcass, portion and organ weights were determined. Physical attributes and proximate composition were analyzed for, with additional fatty acids and sensory profiles being determined for the effects of canola meal inclusion in the diet. Caged hens had heavier (P ≤ 0.05) warm and cold carcasses, thigh, wing and feet compared to free range hens. The percentages of the breast (26.1 ± 0.51 vs. 28.3 ± 0.28), drum, breast bones, breast thaw and cooking losses and thigh cooking loss were lower (P ≤ 0.05) for caged hens than for free range hens. Free range hens had heavier (P ≤ 0.05) gizzards (33.9 ± 1.04 vs. 30.5 ± 0.73) and bones and a lower (P ≤ 0.05) breast meat percentage (47.3 ± 0.94 vs. 51.7 ± 1.35). Meat redness (a*) (0.54 ± 0.222 vs. 1.40 ± 0.135) and hue angle value, skin redness (a*), breast and thigh, Warner-Bratzler shear force (WBSF) values (breast: 12.37 ± 0.411 vs. 17.10 ± 0.751, thigh: 29.68 ± 0.306 vs. 39.75 ± 0.826), breast moisture and thigh ash content were lower (P ≤ 0.05) for caged hens than free range hens. Caged hens had higher (P ≤ 0.05) thigh thaw loss and breast ash content than free range hens. Canola-fed hens had higher (P ≤ 0.05) drum percentages, breast bone weights and percentages, with lower (P ≤ 0.05) thigh and breast meat percentages. Canola-fed hens had lower (P ≤ 0.05) thaw losses, skin yellowness (b*) and Chroma values, breast fat content with higher cooking losses, skin redness (a*) and hue angle value, as well as breast WBSF (12.37 ± 0.411 vs. 15.43 ± 0.600). Palmitic acid, stearic acid, heneicosanoic acid acid, palmitoleic acid, saturated fatty acids (SFA) (34.0 ± 0.56 vs. 38.7 ± 0.71), n-6:n-3 polyunsaturated fatty acids (PUFA) ratio (5.5 ± 0.13 vs. 7.2 ± 0.28), atherogenic index (IA), thrombogenic index (IT), delta-5 desaturase (D5D, elongase index and thiosterase index were lower (P ≤ 0.05) for canola-fed hen breast meat. Breast meat from conventionally fed hens had lower (P ≤ 0.05) myristic acid, lignoceric acid, nervonic acid, alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), PUFA:SFA ratio (0.7 ± 0.05 vs. 0.9 ± 0.02), n-3 PUFA (3.4 ± 0.31 vs. 5.1 ± 0.17), hypocholesterolemic:Hypercholesterolaemic (h/H), stearoyl-CoA desaturase 16 (SCD16) and stearoyl-CoA desaturase 18 (SCD18). The breast meat from conventionally fed hens had lower (P ≤ 0.05) metallic flavor than that from canola-fed hens. Strong positive correlations were observed for overall aroma with chicken (r = 0.965, P < 0.001) and brothy aroma (r = 0.827, P < 0.001); overall aroma with overall flavor (r = 0.680, P < 0.001), chicken flavor (r = 0.668, P < 0.001) and brothy flavor (r = 0.548, P = 0.006); initial juiciness with sustained juiciness (r = 0.771, P < 0.001) and tenderness (r = 0.537, P = 0.007); sustained juiciness with tenderness (r = 0.790, P < 0.001) and chewiness with residue (r = 0.783, P < 0.001). Whilst strong negative correlations were observed for: sustained juiciness with chewiness (r = -0.655, P = 0.001) and residue (r = 0.783, P < 0.001) and for tenderness with chewiness (r = 0.845, P < 0.001) and residue (r = -0.855, P < 0.001). Results of this study highlight that a free range production system when compared to a conventional cage system increased undesirable carcass and physical meat traits of spent laying hens. On the other hand, canola meal inclusion incorporates beneficial health aspects without affecting the sensory profile of meat derived from spent laying hens, both groups of hens being reared in battery cage system. Spent laying hen breasts can be consumed as a functional food (especially canolafed) since the fat content and composition was observed to be close to that which is recommended for a healthy diet.
- Full Text:
- Date Issued: 2018
Factors influencing the hygienic quality of milk yield from smallholder dairy herds in the Eastern Cape Province, South Africa
- Authors: Dube, Hlengani Paul
- Date: 2018
- Subjects: Milk hygiene
- Language: English
- Type: Thesis , Masters , Animal Science
- Identifier: http://hdl.handle.net/10353/10790 , vital:35761
- Description: The objective of the study was to identify factors influencing the hygienic quality of milk of smallholder dairy herds in the Eastern Cape Province of South Africa. Three smallholder herds participating in the National Animal recording scheme and located in Alexandria and East London District Municipalities were used. 90 dairy animals from 3 farms were used, each farm consisting of 30 animals. Three breeds of ten animals were randomly chosen from each farm, the three breeds include, (Holstein, Jersey and Crosses), and four seasons, (autumn, winter, spring and summer) were used to determine the effects of breed and season on the hygienic quality of milk. Milk components included fat percentage, protein percentage, lactose percentage, milk urea nitrogen, milk yield and somatic cell counts (SCC). A total of 1080 milk samples were collected in the afternoon after milking. Procedure of general linear model of SAS was used to determine the effects of breed, season and farm of the milk quality parameters. Means were separated by PDIFF test (α = 0.05). Fixed effects of season, breed and farm, along with 2 way interactions of season and farm and breed and farm were determined. An evaluation template was used to identify the factors affecting hygienic quality of milk. Descriptive statistics (frequencies and percentages) were used. In order to investigate associations between variables of interest, a Pearson Chi-square test was done. The Chi-square test was also used to determine significantly independent findings at a P < 0.10 level of confidence. Cross tabulations were done to establish a basis for comparison and to find out if there is a relationship between two or more variables. The breeds kept within the smallholder dairy herds include Holstein, Jersey, Ayrshire, Guernsey and their Crosses. All farmers’practised pasture based dairy farming system, which includes exclusive dairy production and dairy with other animals like poultry and pigs. 33.33 percent of the smallholder herds use the machine milking method, while 66.67 percent use both the machine and hand milking methods. Milking time is uniform throughout the farms, with milking being done twice a day, in the morning and afternoon. The hygiene practices of the farms were largely similar from farm to farm. Before milking, the udders and teats of animals are washed with clean running water. After milking, the teats of the animals are dipped in teat dip to prevent mastitis. All the farmers’ dairy milking facilities have a permanent water source with continuous supply throughout the year. The water sources vary according to farms, with 33.33% use boreholes, while 66.67 percent utilise rivers and springs. Farmers face numerous challenges such as ageing and dilapidated equipment and infrastructure, limited capital that reduces the number of employees on farm and the purchase of feed inputs to support the milking procedure. Effect of season on milk quality, were significantly (P <0.001) different in milk yield, lactose, and somatic cell counts, and significant different at (P < 0.05) for milk urea nitrogen. High milk yields are observed in spring, and winter, while low milk yields are observed in autumn. High values for fat and protein content were observed in winter. High somatic cell counts were observed in autumn than in spring summer and winter. Effects of farm, on milk quality were significantly (P < 0.001) different on milk yield, fat, protein, lactose, and milk urea nitrogen, and significantly different (P < 0.01) for somatic cell counts. Milk yields varied from 14.03kg/day, 15.51kg/day, and 20.12kg/day, fat percentage varied from 4.52 percent, 4.36 percent, and 4.18 percent, protein percentages of 3.55 percent, 3.44 percent, and 3.47 percent, lactose percentage of 4.47 percent, 4.65 percent, and 4.69 percent, somatic cell counts of 588.42cells/ml, 308.90cells/ml, and 437.43cells/ml, and milk urea nitrogen of 9.84mg/100ml, 10.03mg/100ml, and 10.91mg/100ml for High heaven, Soqhayisa and Matshibele farms respectively. Effect of breed on milk quality, were significantly (P < 0.001) different for milk yield, fat and protein percentage. Milk yields amongst breeds varied at 15.57kg/day, 17.92kg/day, and 16.18kg/day, fat percentages of 4.51 percent, 4.18 percent, and 4.37 percent, protein percentages of 3.55 percent, 3.39 percent, and 3.52 percent, for Jersey, Holstein Cross bred breeds respectively. There were no differences in lactose percentage, somatic cell counts, and milk urea nitrogen amongst breeds. The interaction between farm and season had an effect on milk yield (P < 0.0004), lactose (P < 0.0001), somatic cell counts (P < 0.0001), milk urea nitrogen (P < 0.0019). Milk fat and protein had no effect of farm and season. The interaction between farm and breed had an effect on milk yield (P < 0.0018), fat (P < 0.0001), protein (P < 0.0001), lactose (P < 0.0227), milk urea nitrogen (P < 0.0373). Farm and breed had no effect onsomatic cell counts. The effect of the farm had a greater detrimental effect on the variations in milk composition within the season and the breed. Milk quality is mainly affected by the farm management practices which at times are affected by the farmer’s resources to achieve the basic routine activities for clean milk. Improving the hygienic practises such as udder cleaning, removal of feed from the troughs, and environmental sanitation will increase milk quality in smallholder herds. Smallholder dairy herds were able to meet the milk quality standards of low somatic cell counts that are acceptable as grade A milk.
- Full Text:
- Date Issued: 2018
Effects of different grazing system on forage production and seasonal parasite loads in beef cattle
- Authors: Rapiya, Monde , Mupangwa, John
- Date: 2017
- Subjects: Grazing Forage plants Forage
- Language: English
- Type: Thesis , Masters , (MSc) Pasture Science
- Identifier: http://hdl.handle.net/10353/9253 , vital:34314
- Description: The objectives of the study were to determine the effects of grazing systems on rangeland biomass yield and nutritional composition, tick and faecal egg counts in beef cattle across seasons. The study was conducted at Merino Walk farm located in Matatiele in the northern part of the Eastern Cape Province, South Africa. The farm was divided into three experimental plots of 3.5 ha each. Thereafter, three grazing treatments namely, Holistic Planned Grazing (HPG paddocks), Four-camp rotation (FCR) and continuous grazing (CG), were randomly allocated to the experimental plots. In the FCR system, the 3.5ha was subdivided into four 0.875-ha paddocks, while the HPG system was subdivided into ninety (90) 0.039-ha paddocks. Common forages were hand-clipped at a grazing height of (5cm) in the wet and dry season from six quadrats (0.25m2) placed in each plot and evaluated for biomass yield and nutritional composition. Thirty (30) steers of the same age 12-month old of similar weight were randomly allocated to three grazing treatments (10/treatments). Tick counts were recorded for each steer in the hot-wet, hot-dry, post-rainy and cold dry seasons. Faecal samples were collected per-rectum every in four seasons and analysed for faecal egg counts using the modified McMaster method. The data were analysed using PROC Generalized Linear Model of SAS (2012) to determine the effects of grazing system on rangeland biomass yield, nutritional composition, tick and faecal egg counts. The common grass species in all grazing system across season were Cynodon dactylon, Eragrostis chloromelus, Eragrostis plana, Fescuta and Themeda triandra. The FCR system in the wet season had significant the lowest (P<0.05) biomass yield of 62605,33kg/ha compared to other treatments which had mean values of 62625,97 and 62625,89kg/ha for HPG and CG, respectively (P<0.05). Crude protein content was higher (P<0.05) in HPG (9.41percentCP) and FCR (9.22percentCP) systems in the wet season compared to CG across seasons. Forage from HPG system, irrespective of season had significant lower starch content than other treatments (P<0.05). Forage from HPG system, irrespective of season had the lower (P<0.05) starch content than other treatments. Regardless of season, CG had higher (P<0.05) NDF (72.51 and 72.50) and ADF (41.93 and 40.45) contents than FCR and HPG treatments. Overall, HPG system regardless of season and FCR in the wet season had higher (P<0.05) in vitro digestibility at 24 and 48hrs (0.38 and 0.66) incubation periods. The tick species identified were Rhipicephalus evertsi evertsi, Rhipicephalus (Boophilus) decoloratus, Hyalomma spp and Amblyomma hebreaum with respective prevalence’s of 32percent, 29percent, 20percent and 19percent. Unidentified roundworms (URW), had the highest faecal egg counts (81.2percent) followed by Coccidia (16.4percent), Nematodirus (1.2percent) and Strongyles (1.2percent). Overall, steers on the CG system during hot-wet season had the highest individual and total tick counts (17.0) whilst those on FCR during the cold-dry season had the lowest counts (6.0). Holistic Planned Grazing had the lowest worm egg counts regardless of season, while CG had the highest counts in the hot wet season (P<0.05). The findings showed that relative to other treatments, the HPG system in wet season had a higher biomass yield and better nutritional composition (high CP, low fibre and high digestibility) with low forage production and quality under CG system during the cold-dry season. Whilst, CG during hot-wet season had the highest total tick and worm egg counts and least counts under HPG during the cold-dry. Based on relatively higher forage production and low parasite loads, HPG could be a better grazing management system than CG and FCR, especially in the wet season. It may be important to evaluate the effect of HPG on animal production, product quality and profitability prior to recommending it for use by farmers.
- Full Text:
- Date Issued: 2017
Consumer perceptions and values on beef quality: implications on beef markets
- Authors: Mabhera, Sunungukai.
- Date: 2015
- Subjects: Beef -- Quality -- Health aspects -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape , Beef cattle -- Breeding -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11224 , http://hdl.handle.net/10353/d1020173 , Beef -- Quality -- Health aspects -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape , Beef cattle -- Breeding -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape
- Description: Beef constitutes an important part of many consumers’ diets. Beef is the most consumed red meat in South Africa. Consumer perceptions can affect the whole supply or value chain of beef. Recently there has been increased interest in food safety; greater concern for environmental and animal welfare issues, increased importance of eating quality and healthy food as well as the greater role of food services. The demand for beef is no longer limited to economic factors alone but to non-economic factors as well. Consumers of beef in Alice have become more concerned about meat-borne risks and personal health. This research prioritized the exploration of the beef consumers’ (i) self-perception (ii) price perception (iii) benefit perception [in the form of – (a) value perception and (b) quality perception]. The study was conducted in the Eastern Cape Province specifically in Alice town and the surrounding rural areas (Ntselamanzi, Gaga, Hillcrest, Gqumashe, and Dyamala) of the Nkonkobe municipality. Anyone who admitted to eating beef and at the point of data collection bought beef for their own consumption or family consumption was deemed as a unit of analysis. Non – probabilistic sampling techniques which included accidental and random sampling were used to collect data from 100 interviewees. A semi structured questionnaire was used to analyse the perceptions and attitudes of beef consumers. The respondents were asked to indicate their agreement or disagreement with 47 statements or items presented on either five alternatives in a Likert scale scored from 1 (strongly disagree) to 5 (strongly agree) or a six Likert scale ranging from 1 (very low) through 5 (very high) to 6 (I do not know).The data was analysed using SPSS. It was discovered that beef consumers did not consider either intrinsic or extrinsic cues in isolation when purchasing beef but rather all characteristics contribute to the final perception. The Alice consumer market is heterogeneous and consists of different races with different cultures and market segments with varying needs and preferences. The results showed that five factors were extracted from forty seven items Factor 1: Information reliance and quality indication; Factor 2: convenience; Factor 3: Traceability and animal Welfare; Factor 4: Health and safety Conscious and Factor 5: Price and Branding. Furthermore, four main consumer segments emerged as - Segment 1: Informed buyers; Segment 2: Elite buyers; Segment 3: Health & safety conscious buyers and Segment 4: Apathetic buyers. The cluster analysis shows that quality is a subjective concept that is informed by a consumer’s personal taste and preferences. Taste and preferences inform the consumer’s effective demand which in retrospect is informed by the consumer’s socioeconomic status.
- Full Text:
- Date Issued: 2015
Effect of pre-slaughter stress of pigs on the levels of cortisol, creatine kinase and their subsequent relationship with pork quality
- Authors: Nzolo, Jama
- Date: 2014
- Subjects: Slaughtering and slaughter-houses , Pork -- Quality , Swine -- Handling , Livestock -- Handling , Creatine kinase
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11837 , http://hdl.handle.net/10353/d1021287 , Slaughtering and slaughter-houses , Pork -- Quality , Swine -- Handling , Livestock -- Handling , Creatine kinase
- Description: The study was conducted to determine the effect of pre-slaughter stress of pigs on the levels of cortisol, creatine kinase (CK) and their subsequent relationship with pork quality. From our knowledge, there is paucity of information on transportation, lairage duration and sex effects on saliva cortisol and its relation with serum cortisol, urine cortisol and other meat quality traits. Stage one of the study assessed the effect of sex and time to slaughter (transport and lairage duration) on the levels of cortisol and CK in crossbred pigs. The second stage of the study evaluated the effect of sex and lairage duration on pork quality. The trials comprised of 60 22-weeks old commercial crossbred pigs [(30 boars vs. 30 gilts) with an average body weight of 76.9kg for gilts and 78.3kg for boars. Thirty pigs (15 Boars vs. 15 Gilts) were slaughtered on arrival after a 120km road journey and the other 30, after travelling the same road and distance, were slaughtered after having been in the lairage for 20 hours. Saliva samples were obtained during three time periods: between 07:00-10:00 on the day before the journey, on arrival at the abattoir and after lairage. Levels of cortisol in serum and urine and CK in serum samples collected at slaughter were determined. The samples (saliva and serum) were centrifuged at 20oC for 10 min at 3550 x g and stored at -20oC in separate vials until analysis. Pork quality was assessed using muscle pH, colour, thawing and cooking losses and Warner-Bratzler Shear Force. Correlations between cortisol levels in saliva, serum and urine and meat quality were assessed. The effect of sex and time to slaughter on saliva cortisol was significant. Statistical analysis showed significant interaction of sex by time to slaughter on serum cortisol. It was only the effect of sex that demonstrated higher (P <0.05) serum creatine kinase levels in gilts. Likewise, urine cortisol was influenced (P <0.05) only by time to slaughter. Saliva cortisol after transportation (r = 0.52) was correlated (P <0.05) with urine cortisol. The study suggests that there are greater responses of the Hypothalamic-pituitary-adrenal axis following time to slaughter (transport and lairage duration) between gilts and boars. This can be used in measuring cortisol in saliva, serum and urine, and serum creatine kinase to determine stress levels in pigs. Besides the lightness (L*) colour value which was significantly lower (P <0.05) in meat from gilts than from boars, the results of this study showed no interaction or individual effect (sex or lairage duration) on pH and other colour measurements. Meat cooking loss was affected (P <0.05) by gender x lairage interaction. Effect of lairage duration (as an individual effect) on the measured meat quality traits was not significant (P <0.05). Correlation analysis showed significant (P <0.05) negative relation between baseline saliva cortisol (r = -0.40) and the pork L* value. Saliva cortisol after lairage duration (r = -0.38 and r = 0.38) was correlated (P <0.05) with pH45 and pork a* value, respectively. Serum cortisol (r = -0.35) was negatively correlated (P <0.05) with pH45. Moreover, there were negative correlations (P <0.05) between saliva cortisol after transportation (r = -0.35), saliva cortisol after lairage duration (r = -0.44), serum cortisol (r = -0.40) and meat cooking loss. The study suggests that cortisol in saliva and serum can be used to determine effect of time to slaughter (transport and lairage duration) on meat quality traits from gilts and boars. Keywords: Boars; gilts; saliva cortisol; serum cortisol; serum creatine kinase; urine cortisol.
- Full Text:
- Date Issued: 2014
Effects of dietary inclusion of Moringa oleifera leaf meal on growth performance, physico-chemical attributes, oxidative stability and sensory quality of pork
- Authors: Nduku, Xola Pauline
- Date: 2014
- Subjects: Pork -- Quality , Food -- Sensory evaluation , Fatty acids , Moringa , Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11836 , http://hdl.handle.net/10353/d1021281 , Pork -- Quality , Food -- Sensory evaluation , Fatty acids , Moringa , Meat -- Quality
- Description: The objective of the study was to determine growth performance, physico-chemical attributes, oxidative stability and sensory quality of pork from pigs fed one of three dietary treatments, eac containing 0%, 2.5% or 5% (T1, T2 and T3, respectively) Moringa oleifera leaf meal (MOLM). Dietary treatments were formulated to be isonitrogenous and isoenergetic for weaner (6 – 8 weeks) and grower (9 – 13 weeks) phases. Twelve Large White (LW) and 12 Kolbroek (KB) male pigs at 6 weeks of age, initially weighing an average 10 kg, were randomly allocated to one of the dietary treatments, each with four replicates, in individual pens. Feed and water were offered ad libitum. The Longissimus thoracis et lumborum (LTL) muscle of each carcass (n = 24) was sampled for meat quality and fatty acid analyses. Breed differences in measured parameters were observed. In pigs receiving 5% MOLM, the LW had significantly the highest ADFI (P<0.05) than KB pigs. In pigs receiving 2.5% and 5% MOLM, backfat thickness was significantly highest (P<0.05) compared to those receiving 0% MOML. Dietary inclusion of MOLM had no significant effects (P>0.05) on the physico-chemical quality of pork from LW pigs; although it significantly (P<0.05) increased a* and reduced WBSF values in pork from KB pigs. Pork from LW pigs receiving 5% MOLM had significantly increased (P<0.05) n-3 content of the subcutaneous tissue of LW pigs compared to KB, and also when compread to other treatment groups. In both breeds, the composition of PUFA: SFA and n-6: n-3 in the subcutaneous adipose tissue was significantly (P<0.05) lower in T2 and T3 than in T1. The n-3 levels for pork muscle from LW pigs receiving 2.5% and 5% MOLM, and from KB pigs receiving 5% MOLM, were significantly (P<0.05) lower. Inclusions of MOLM significantly (P<0.05) reduced the n-6: n-3 fatty acids in pork from both LW pigs and KB pigs. Consumer scores on sensory attributes (aroma intensity, initial impression of juiciness, first bite, sustained impression of juiciness, muscle fibre and overall tenderness and overall flavor intensity) significantly (P<0.05) increased as the level of MOLM inclusion in the diet increased; and higher scores were observed in fried meat than in boiled for most sensory attributes. It may be concluded that inclusion of MOLM in pig diets up to 5% improved the ADFI, a*, tenderness of pork without adversely affecting the FCR and other physico-chemical quality attributes; and resulted in desired increase in levels of n-3 and reduced the n-6: n-3 fatty acid ratio.
- Full Text:
- Date Issued: 2014
Perceptions of rural consumers on behaviour and beef quality of cattle slaughtered for traditional ceremonies in the Eastern Cape of South Africa
- Authors: Soga, Sizwe William
- Date: 2014
- Subjects: Meat -- Quality , Consumers' preferences , Consumers -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11833 , http://hdl.handle.net/10353/d1019812 , Meat -- Quality , Consumers' preferences , Consumers -- South Africa -- Eastern Cape
- Description: The objective of the study was to determine perceptions of the consumers on how they judged behaviour and beef quality of cattle slaughtered for traditional ceremonies in the Eastern Cape Province of South Africa. A survey was conducted where a sample of 200 consumers were randomly selected and interviewed. Fifty non-descript cattle were slaughtered during traditional ceremonies and two hundred and twenty four (224) cattle were slaughtered at 3 through-put abattoirs (high, medium and low). Meat quality attributes were determined from the cattle slaughtered for traditional ceremonies and from cattle slaughtered at the abattoirs. Data for questionnaires was summarized as frequencies for each ceremony and statistical differences were analysed using chi square test (X2). The effect of Age, breed and sex on beef pH, colour, meat tenderness, temperature and cooking loss of cattle slaughtered during traditional ceremonies, at low, medium and high throughput abattoirs were analyzed using General Linear Model (PROG GLM) of SAS (2003). There was a significant age effect (P < 0.05) on beef tenderness and cooking loss of cattle slaughtered for traditional ceremonies. Age of cattle that have milk teeth to 1 year and age of 6 years to 8 years had an effect on the beef tenderness (25.55 ± 8.05) and cooking loss (48.00 ± 4.26) of cattle slaughtered for traditional ceremonies in Table 4.1. There was no significant sex effect on beef tenderness and cooking loss of cattle slaughtered for traditional ceremonies. Non-descript and Angus cattle slaughtered at low throughput abattoir had an effect on the colour of the beef in Table 4.2. The lightness (27.49 ± 2.53) and yellowness (21.16 ± 0.79) of the beef shows that there was a significant breed effect on cattle that are slaughtered at Low throughput abattoir, however redness of the meat was not affected by breed after slaughter. Cattle that are slaughtered at high throughput abattoir between ages of 6 to 8 years and also cattle that are more than 8 years in Table 4.4 had an effect on cooking loss (p < 0.05). Age between 6 to 8 years had an effect on the beef tenderness from cattle that are slaughtered at medium throughput abattoir. It was concluded that the meat tenderness of the young cattle with milk teeth slaughtered for traditional ceremonies was affected. On the other hand the meat tenderness and cooking loss of beef from the cattle slaughtered from low, medium and high throughput abattoir were affected by sex and breed mostly.
- Full Text:
- Date Issued: 2014
Socio-economic importance, health and welfare aspects of donkeys (Equus asinus) used for carting in a peri-urban area of South Africa
- Authors: Marufu, Madure
- Date: 2014
- Subjects: Donkeys -- South Africa , Animal welfare , Donkeys -- Handling , Donkeys -- Health
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11832 , http://hdl.handle.net/10353/d1019781 , Donkeys -- South Africa , Animal welfare , Donkeys -- Handling , Donkeys -- Health
- Description: The broad objective of the study was to determine the socio-economic importance, health and welfare aspects of donkeys used for carting in a peri-urban area. A survey was conducted among 71 donkey owners in Joza, a peri-urban area near Grahamstown in the Eastern Cape Province (ECP) of South Africa to investigate their perceptions on socio-economic importance, health and welfare aspects of donkeys used for transport. Two hundred and seventy-one donkeys used for carting were assessed through direct observation of health and behaviour parameters to determine their welfare status. Results revealed that donkeys are indeed of immense value to people, being used daily (54.93%) for income generation activities and at least once per month (7.08%) for domestic chores. Most of the respondents (32%) earned R 600.00 per week while 11% earned at least R 200.00 per week from carting using donkeys. Donkeys were used for carting of goods (90.14%) more than for manure (16.9%). Gender and age of owners significantly (P < 0.05) influence perceptions on source of income while education level influenced their perceptions on carting firewood, goods and water. Results on management practices and health problems encountered by working donkeys showed that most of the owners managed their animals poorly. Most donkeys were being beaten (74.65%) during work, made to travel long distances (43.66%), worked long hours (52.11%) without adequate water (59.10%) and feed supplements (83.10%). Wounds (95.97%), coughing (75.65%) and lameness (64.79%) were some of the health problems encountered by donkeys. Significant relationships (P ˂ 0.05) were observed between owners’ perceptions on management practices and health problems encountered by donkeys. Among the observed animals, 61% were thin and mostly apathetic (26.2%) than medium and fat animals. Responses to observer approaches were significantly associated with sex and body condition score (BCS), with stallions in good body condition being more aggressive. Donkeys having a BCS of 3-5 avoided chin contact either by kicking out or moving away. Results further showed that most of the donkeys were suffering from external injuries, with the hindquarters (39.85%), shoulder (32.10%) and spine (21.77%) being the mostly affected areas. The prevalence of wounds on tail-base, belly, flank and neck were seen in less than 13% of the animals. The prevalence of wounds was influenced by age and BCS of the animals. Young donkeys with good BCS were less affected than old donkeys. Lameness, poor coat condition, external parasites, abnormal mucous membrane and dental problems were observed in less than 30% of the animals. It was concluded that donkeys play a pivotal role economically and socially to the livelihoods of people in a peri-urban area (Joza) in terms of income generation and transportation. However, these animals are experiencing multiple health and welfare problems. Therefore, more access to veterinary services, training on donkey use and management, health and welfare promotion programs are of paramount importance in solving the problem of poor health and welfare in donkeys.
- Full Text:
- Date Issued: 2014
Application of assisted reproduction technologies on the indigenous Nguni cows and heifers
- Authors: Maqhashu, Ayanda
- Date: 2013
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11828 , http://hdl.handle.net/10353/d1016096
- Description: The aims of the study were to compare superovulatory (SO) response rate and embryo quality recovered; consequently, correlate sperm motility with fertilization rate on superovulated stud Nguni cows and heifers. Furthermore, compare oestrous synchronization response and pregnancy rate of three breed type cows (Brahman, Bonsmara and Nguni) of different body condition scores following timed artificial insemination in KwaZulu-Natal (KZN) and Limpopo provinces. Nguni stud cows (n= 15) and heifers (n= 10) aged 4-6 and 2-3 years were used as embryo donors. Superovulation of donors involved insertion of a controlled internal drug release device (CIDR) and two injections of FSH daily 12 hours apart for 4 days on a decreasing dosage. Fresh Nguni semen was collected from proven Nguni stud bulls and assessed by computer aided sperm analysis (CASA) before artificial insemination (AI). The doses of AI were prepared and conducted twice, 12 hours apart on synchronized and superovulated Nguni cows or heifers. Embryos were flushed 7 days after AI using a non-surgical technique. Embryos were immediately evaluated under stereo microscope and classified according IETS standard codes (C1, C1- and C2). All transferrable embryos were vitrified. Two pilot study sites were chosen in Eastern Cape – Great kei; (n= 5) and Limpopo - Vuvha; (n=5) provinces for Embryo transfer. Each recipient cow was implanted with one frozen-thawed embryo. For oestrous synchronization, cows (Braman, Bonsmara and Nguni type) were selected in different villages, regardless of parity, age, breed and body weight following pregnancy diagnosis. Cows were grouped according to breed type and body condition scores (BCS) on a scale of 1-5. Group 1 had BCS of ≤ 2.5 in KwaZulu-Natal (n=81) and Limpopo n=71), Group 2 had BCS of ≥ 3 in KwaZulu-Natal (n=79) and Limpopo (n=100) cows. Cows were synchronized by inserting the controlled intravaginal drug release (CIDR) and removed on Day 8, followed by administration of prostaglandin. The white heat mount detectors (HMD) were placed on the individual cow’s tail head as an indicator for oestrous response if colour changed to red and inseminated twice at 12 hours interval. Pregnancy diagnosis was performed by an ultra sound scanner and rectal palpation 90 days after TAI in embryos and semen recipient cows. There was no significant difference on the superovulatory response rate between Nguni cows (40%) and heifers (40%). There was a significant difference on the ovary reaction (number of corpus luteum) of cows (11.33±1.41) and heifers (4.00±0.57). There were no significant differences observed on the embryo quality between Nguni cows (2.5±1.00 and 1.25±0.59) and heifers (0.83±0.41 and 1.00±0.36) for excellent (C1) and good (C1-). However, cows had more numbers of unfertilized ova (5.5±1.05 and 1.75±0.47) and degenerate embryos (3.66±1.00 and 1.25±0.39) than heifers. Village cows responded to oestrous synchronization successfully in KZN (100%) and Limpopo (99%) regardless of body conditions and breed type. The lowest pregnancy rate was recorded in Brahman and Bonsmara type cows with BCS of ≤ 2.5 regardless of Province. Interestingly, Nguni type cows with same body condition of ≤ 2.5 had higher average pregnancy rate of 59.5% in Limpopo and 53.5% in KZN. However, cows with BCS of ≥3 had better pregnancy rate regardless of cow breed type, and province. In conclusion, only 40% of both Nguni cows and heifers responded to superovulation. However, Nguni cows had better ovaries reaction compared to heifers. The quality of embryos recovered was similar for both Nguni cows and heifers. Moreover, there was a positive correlation between total sperm motility and fertilization rate bull 1 (93.7%) inseminated the cows (67.5%) and bull 2 (83.5%) inseminated the heifers (53.5%). Higher pregnancy rate (60%) was recorded in Limpopo compared to Eastern Cape (0%). Interestingly, more than 99% of village cows responded to synchronization and inseminated with frozen-thawed semen successfully. Village Nguni type cows were not affected by body condition scoring as they had higher and similar pregnancy rate as those that had body condition of ≥ 3. It is suggested that it is not advisable to breed synchronized Brahman and Bonsmara type cows with the body condition of ≤ 2.5 except in Nguni cow type as more than 57% average pregnancy rate was achieved.
- Full Text:
- Date Issued: 2013
Effect of agricultural extension services on beneficiaries of the Nguni cattle project: the case of Ncera and Kwezana villages, Eastern Cape Province
- Authors: Gwala, Lindokuhle
- Date: 2013
- Subjects: Agricultural assistance -- South Africa -- Eastern Cape , Agricultural extension work -- South Africa -- Eastern Cape , Agriculture, Cooperative -- South Africa -- Eastern Cape , Farmers -- Education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11219 , http://hdl.handle.net/10353/d1019814 , Agricultural assistance -- South Africa -- Eastern Cape , Agricultural extension work -- South Africa -- Eastern Cape , Agriculture, Cooperative -- South Africa -- Eastern Cape , Farmers -- Education -- South Africa -- Eastern Cape
- Description: The study was conducted to determine the effect of agricultural extension services on beneficiaries of the Nguni Cattle project in Ncera and Kwezana villages, both in Nkonkobe local Municipality of the Eastern Cape Province. The objectives of this study were to determine the quality of extension services offered to the beneficiaries of the Nguni cattle project, relationship between extension officers and beneficiaries of the project, lastly was to determine communication strategies used by extension officers to communicate with the project beneficiaries. A total of 73 Nguni cattle project beneficiaries were interviewed. Semi- structured questionnaires were administered to the beneficiaries of the project who were willing to participate in the study. Xhosa speaking enumerators assisted in data collection. Focus group discussions were later carried out in both villages to determine effect of agricultural extension services on socio-economic status of the beneficiaries. The focus groups were divided into three groups of different ages and gender. The majority of the beneficiaries in the project were males (62.2 % Ncera and 75% Kwezana). There was an association between gender and extension services. Farmers depended on different sources of income. Old age pension and animal sales being the main contributing sources and also having a significant difference. The results of the study further revealed that the beneficiaries were faced with cattle production challenges, lack of extension support services being the main challenge. The results of the study indicated that the majority of beneficiaries had no access to extension services. Only 37.8% and 32.1 % at Ncera and Kwezana respectively reported that they had access to extension services. Although the latter is the case it was further explained by the beneficiaries that extension services offered to them were of poor quality due to poor communication strategies used to provide these services. Beneficiaries also reported the relationship between them and extension officers’ as poor. It was concluded that extension services had an effect on beneficiaries of the Nguni cattle project, largely based on the constraints they face on the project and limited access to extension services.
- Full Text:
- Date Issued: 2013
Effect of dietary inclusion of Moringa oleifera Lam leaf meal on feed conversion efficiency, meat quality, fatty acid composition, shelf life and consumer health-related perceptions of pork
- Authors: Mukumbo, Felicitas Esnart
- Date: 2013
- Subjects: Moringa oleifera , Meat -- Quality , Feed utilization efficiency
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11827 , http://hdl.handle.net/10353/d1016071 , Moringa oleifera , Meat -- Quality , Feed utilization efficiency
- Description: The objective of the study was to determine the feed conversion efficiency (FCE), carcass characteristics, physico-chemical quality, fatty acid (FA) composition and shelf life of pork from pigs fed diets containing either 0% (T1), 2.5% (T2), 5% (T3) or 7.5% (T4) Moringa oleifera leaf meal (MOLM). Consumer health-related perceptions on pork and fatty acids were also investigated. Twenty four crossbred Large White x Landrace pigs of both sexes at 18 weeks of age and initially weighing 71.6 kg on average were housed individually and had ad libitum access to one of the four dietary treatments for a period of six weeks. Average daily feed intake (ADFI) and average daily gain (ADG) and feed conversion ratios (FCR) were calculated as an indication of FCE and pigs were slaughtered at an average live weight of 99.6 kg. Carcass traits such as back fat thickness (BFT), carcass temperatures and pH readings taken 45 minutes and 24 hours (pH45 and pHu) post mortem were recorded. M. longissimus thoracis et lumborum (LTL) samples were taken from each carcass for the determination of lightness (L*), redness (a*), yellowness (b*), thawing loss percentage (TL%), cooking loss percentage (CL%), Warner Bratzler Shear Force (WBSF), shelf life and FA composition. Furthermore a survey was conducted amongst 80 University of Fort Hare Students to determine their health-related perceptions on pork and fatty acids as well as their pork consumption frequency using questionnaires. The FCE of pigs fed on 0-5% MOLM (T1, T2 and T3) diets did not differ significantly, but the FCE of pigs fed 7.5% MOLM (T4) was significantly (p<0.05) reduced. No significant relationship was reported between inclusion of MOLM carcass characteristics and physico-chemical pork quality. There was however a significant improvement (p<0.05) in the shelf life of the pork from MOLM fed pigs in terms of colour and odour during 10 days of refrigerated storage (at 3±1°C). There was a significant (p<0.05) reduction in the total intramuscular fat (IMF) content and the saturated fatty acid (SFA) C18:0 (stearic acid) content and an overall non-significant (p>0.05) increase in the poly unsaturated fatty acid (PUFA) content of pork from MOLM fed pigs. The possible reason for this is that the feeding of MOLM was commenced when the pigs were at an advanced age and weight. The survey revealed that the majority of interviewed students consume fresh (39.7%) and processed (32.4%) pork two to three times a week, perceive pork to be generally healthy (70%) and the second most healthy meat type (39.5%). While the majority (55.4%) were aware of the health implications of FAs they did not know which FA classes pose more of a health risk (51.3%). In conclusion2.5% and 5% of MOLM in finisher pig feed did not negatively affect FCE, carcass characteristics or physico-chemical meat quality; significantly improved pork shelf life and reduced total IMF and SFA content of pork but 7.5% MOLM negatively affected FCE; and the majority of students perceive pork to be the second most healthy type of meat and are generally aware of the health implications of FAs.
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- Date Issued: 2013
Incidence of Staphylococcus species in bovine milk: their antimicrobial sensitivity in selected antibiotics and Usnea barbata lichen extracts
- Authors: Idamokoro, Emrobowansan Monday
- Date: 2013
- Subjects: Staphylococcus , Microbial sensitivity tests , Traditional medicine , Lichens -- Analysis , Mastitis , Antibiotics in agriculture
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11829 , http://hdl.handle.net/10353/d1016193 , Staphylococcus , Microbial sensitivity tests , Traditional medicine , Lichens -- Analysis , Mastitis , Antibiotics in agriculture
- Description: This study was done in order to assess the incidence of Staphylococcus species from milk of cows with subclinical mastitis and their antimicrobial sensitivity in some selected antibiotics and Usnea barbata lichen extracts. The study was conducted in two different commercial dairy farms. Staphylococcus species isolates were identified using several biochemical tests which included Gram’s staining test, catalase test and oxidase test. A commercial API® staph kit (bioMerieux, France) was used to confirm the bacterial organisms to their species level. The antimicrobial sensitivity of individual species was determined according to the Clinical Laboratory Standard Institute (CLSI) for the selected antibiotics. Agar well diffusion method and the broth micro-dilution technique were used to determine the sensitivity of Staphylococcus species in U. barbata extracts. A total of 467 milk samples were screened for bacterial identification from the two farms. Fifteen different Staphylococcus species isolates were identified from all milk samples that were examined. The most frequently isolated species included Staphylococcus xylosus (54.34%), Staphylococcus hominis (24.78%), Staphylococcus aureus (16.38%), Staphylococcus saprophyticus (16.12%) and Staphylococcus haemolyticus (11.63%). Most Staphylococcus species were resistant to Penicillin (75.35%), Nalidixic acid (72.55%) and Ampicillin (63%). Furthermore, the bacterial sensitivity evaluation of U. barbata lichen extracted with methanol and ethyl-acetate against selected Staphylococcus species isolates showed 92.31% and 53.85% susceptibility, respectively. The minimum inhibitory concentration (MIC) of the methanol and ethyl-acetate extracts ranged between 0.0390 to 10 mg/ml. There was a relatively high incidence of Staphylococcus species identified in milk of cows with subclinical mastitis from both farms. Conversely, Staphylococcus species isolates were resistant to antibiotics (mostly penicillin and ampicillin) commonly used in the farms. Furthermore, the study investigated the antimicrobial sensitivity of U. barbata extract in-vitro which may validate its use in traditional medicine for treatment of cows with mastitis.
- Full Text:
- Date Issued: 2013
Some performance characteristics of wooled sheep in the sweet and sourveld communal rangelands of Eastern Cape Province, South Africa
- Authors: Mvinjelwa, Sivuyile Alex
- Date: 2013
- Subjects: Wool industry -- South Africa -- Eastern Cape , Sheep -- South Africa -- Eastern Cape , Wool -- South Africa -- Eastern Cape , Veld -- South Africa -- Eastern Cape , Communal rangelands -- South Africa , Grazing -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11825 , http://hdl.handle.net/10353/d1015592 , Wool industry -- South Africa -- Eastern Cape , Sheep -- South Africa -- Eastern Cape , Wool -- South Africa -- Eastern Cape , Veld -- South Africa -- Eastern Cape , Communal rangelands -- South Africa , Grazing -- South Africa -- Eastern Cape
- Description: The objective of the study was to determine sheep growth performance, fleece weights and wool quality characteristics in the sweet and sourveld communal rangelands of the Eastern Cape Province of South Africa. Data were obtained in 80 ewes aged two to three years, selected in four ecologically different communities. Two communities (Roxeni and Tyabane) were in a sweetveld area and the other two communities (Luzi I and Luzi II) were in a sourveld area. The ewes from Tyabane were nondescript, whereas ewes from Roxeni, Luzi I and Luzi II were crossbred between Merinos and non-descript sheep. Selected ewes were monitored for live weight, body condition scoring and fleece weight during shearing. Wool samples were collected from each ewe and were analysed for fibre diameter, comfort factor, clean yield, wool crimps, staple length, staple strength and the Position of break. Sheep from Roxeni were heavier (P <0.05) (39.9 ± 1.1kg) than sheep from Tyabane (29.8 ± 1.1kg). Sheep from Tyabane had the lightest (P <0.05) fleece weight (1.0 ± 1.1kg) and sheep from Roxeni had the heaviest (3.1 ± 1.1kg). There were no significant differences (P ≥0.05) between body condition scores of sheep in Roxeni and the Luzi communities. The live weights of the two-year old ewes were similar (P ≥0.05) to the three-year old ewes’ live weight. However, the three year old ewes had higher (P <0.05) body condition scores than the two year old ewes. Two year old ewes also had lower (P <0.05) fleece weight than the three years old ewes. Wool from Roxeni, Luzi I and Luzi II had lower fibre diameter (P <0.05) than wool from Tyabane. Roxeni sheep had the highest clean yield (P <0.05) of wool, followed by Luzi I and Luzi II; Tyabane had lowest clean yield percentage of wool. Wool from sheep grazing on sweetveld had a higher (P <0.05) clean yield percentage (74.3 ± 0.7%) than those grazing on sourveld (71.7 ± 0.7%). There were higher staple mid-breaks (69.5 ± 5.2) and lower base-breaks (30.5 ± 5.2) in sweetveld (P <0.05) than in sourveld, 7.5 ± 5.2 and 92.5 ± 5.2 for mid-breaks and lower base-breaks, respectively. It was concluded that sheep raised in the sweetveld and bred with purebred Merino rams had higher performance than the ones reared in the sourveld. The young upgraded ewes had a higher wool quality than the older ewes raised on communal rangelands.
- Full Text:
- Date Issued: 2013
Time budgets, blood urea content, total protein and body condition scores as adaptive responses to seasonal dynamics by breeding Nguni cows and heifers reared on a sweetveld
- Authors: Mapfumo, Lizwell
- Date: 2013
- Subjects: Nguni cattle -- South Africa , Cattle -- Feed utilization efficiency -- South Africa , Beef -- Quality -- South Africa , Slaughtering and slaughter-houses -- South Africa , Cattle -- Breeding -- South Africa
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11826 , http://hdl.handle.net/10353/d1015738 , Nguni cattle -- South Africa , Cattle -- Feed utilization efficiency -- South Africa , Beef -- Quality -- South Africa , Slaughtering and slaughter-houses -- South Africa , Cattle -- Breeding -- South Africa
- Description: The objective of this study was to determine time budgets, blood urea content, total protein and body condition score as adaptive responses to seasonal dynamics by breeding Nguni cows and heifers reared on a sweetveld. Twenty four clinically healthy Nguni cows and heifers were selected for the study. The animals were grouped according to their parities namely: Parity 1 (n=5), Parity 2 (n=5), Parity 3-6 (old cows) (n=9) and in-calf heifers (n=5). Two separate experiments were conducted and running concurrently. In the first experiment time budgets (time spent walking, grazing, lying down, drinking water and browsing) of the cows and heifers were monitored for two consecutive days once a month, while in the second experiment blood samples were collected from the coccygeal vein once a month during weighing. Body condition scores were also determined during weighing times. Heifers maintained significantly (p0.05) of both blood urea nitrogen (BUN) (7.5±0.39 mmol/l) and TP (80.7±1.19 g/l) in November. All the animals had the least BUN levels in January (1.93±0.18 mmol/l) while the highest total protein (TP) (82.1±1.08 g/l) was recorded in February. All the animals showed distinct (p0.05) in most behavioural attributes in the cool-wet season. Heifers spent significantly (p0.05) body condition scores, amount of time spent browsing and drinking water. On the other hand, heifers (14.7±1.50%) and first parity cows (13.9±1.50%) traded-off most (p<0,05) of their time walking during the cool-dry season. Similarly heifers spent more time browsing (6.4±0.62%) forage plants (p<0.05) than all the cows during the cool-wet season. Grazing (r = 0.17) and standing (r = -0.18) were correlated (p<0.05) with all the behavioural attributes measured in this environment. It was concluded that seasonal dynamics in trade-off behaviour through time budgeting, maintenance of BUN and TP were necessary for the Nguni cows and heifers to maintain their body condition scores within a narrow range throughout the four seasons.
- Full Text:
- Date Issued: 2013
Avoidance-related behaviour, bleeding times and the quality of meat from sheep slaughtered at a commercial and a municipal abattoir
- Authors: Njisane, Yonela Zifikile
- Date: 2012
- Subjects: Mutton -- Quality , Sheep -- Quality , Slaughtering and slaughter-houses -- South Africa , Animal behavior , Dorper sheep , Meat -- Quality , Sheep -- Carcasses -- Handling
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11818 , http://hdl.handle.net/10353/d1004195 , Mutton -- Quality , Sheep -- Quality , Slaughtering and slaughter-houses -- South Africa , Animal behavior , Dorper sheep , Meat -- Quality , Sheep -- Carcasses -- Handling
- Description: The objective of the study was to determine the avoidance-related behaviour, bleeding times and the quality of meat from sheep of different gender, breed (Dorper, Merino, and their crosses) and age groups, slaughtered at a commercial and municipal abattoir. Castrates and ewes of different age groups (1= <10months, 2= 11-12months, and 3= >12months) and breeds were used. From the commercial abattoir, 90 castrates and 110 ewes were used, while 66 castrates and 19 ewes were obtained from the municipal abattoir. Meat samples were obtained to determine meat colour, ultimate pH, temperature, cooking loss and tenderness. Correlations between bleeding times and meat quality variables were also determined. The two abattoirs differed in terms of technology and the procedures used, and this brought about different response behaviours in sheep at slaughter, bleeding times at exsanguination and the quality of meat produced. Animal-related factors (breed, gender and age classes) had no effect on the avoidance-related behaviour of sheep slaughtered at the commercial abattoir, while these factors affected those sheep slaughtered at the municipal abattoir. These factors also had an effect on the quality of meat produced at both abattoirs. Gender and weight of the animals had effects on the bleeding times at exsanguination at both abattoirs. Bleeding times did no correlate with any of the meat quality variables, but correlations among meat quality variables were observed. Avoidance-related behaviour, bleeding times, and the quality of mutton from sheep slaughtered at a commercial and a municipal abattoir was affected by breed, age, and gender.
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- Date Issued: 2012
Bruising in slaughter cattle: its relationship with creatine kinase (CK) levels and meat quality
- Authors: Mpakama, Thandiswa
- Date: 2012
- Subjects: Beef quality , Creatine kinase , Cattle -- Transportation
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11821 , http://hdl.handle.net/10353/d1006850 , Beef quality , Creatine kinase , Cattle -- Transportation
- Description: The objective of the study was to determine the effects of pre-slaughter conditions and anima-l related factors on bruising, creatine kinase (CK) and beef quality. Three hundred and twenty one cattle from three breeds (108 Bonsmara, 130 Beefmaster and 83 Brahman) were used in this study. The animals were grouped according to age categories as follows; Group 1(16months), Group 2 (18months) and Group 3 (24 months). Blood samples for CK determination were collected at exsanguisation using disposable vacutainer tubes. The Muscularis longisimus thoracis et lumborum (LTL) muscle was used to determine beef colour (L,* a* and b*) and ultimate pH. Significant P (<0.05) breed effects were observed on bruising score and CK levels with Bonsmara breed having the highest percentage (80 percent) of bruising score and higher CK (705.3±80.57) values. The higher CK levels were also in winter season. The effect of breed, sex and age at slaughter on meat quality (pHu, L*, a*, b*) was also observed. There were positive correlations between distance travelled and meat quality, while there was no relationship observed between CK and distance travelled. Therefore, it was concluded that animal related factors had an effect on meat quality and CK levels.
- Full Text:
- Date Issued: 2012
Effect of full and semi-scavenging rearing systems on crop contents and the quality of meat from village chickens during spring season of Eastern Cape, South Africa
- Authors: Hanyani, Charles Tawanda
- Date: 2012
- Subjects: Chickens -- Feeding and feeds -- South Africa -- Eastern Cape , Chicken breeds -- South Africa -- Eastern Cape , Meat -- Quality -- South Africa -- Eastern Cape , Forage plants -- South Africa -- Eastern Cape , Crops -- Nutrition -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11807 , http://hdl.handle.net/10353/440 , Chickens -- Feeding and feeds -- South Africa -- Eastern Cape , Chicken breeds -- South Africa -- Eastern Cape , Meat -- Quality -- South Africa -- Eastern Cape , Forage plants -- South Africa -- Eastern Cape , Crops -- Nutrition -- South Africa -- Eastern Cape
- Description: The objective of this study was to compare the nutrient status of full scavenging and semi-scavenging village chicken production systems. The semi-scavenging chickens were given broiler finisher mash between 14-24 weeks of age, whilst the full scavenging relied on natural foraging. The study also sought to compare the quality of meat from chickens from the two systems. After slaughtering the chickens, the crop contents were physically separated and analysed for chemical composition. Meat pH and colour were measured on the breast muscle of individual carcasses and a consumer sensory evaluation was also done on the breast muscle. The mean crop content weights per day were significantly higher in full scavenging chickens (±16.7g/day biomass) than in semi-scavenging chickens (±9.14g/day). Dry matter, calcium, and phosphorus levels were higher in the crop contents of the full than in the semi-scavenging chickens but crude protein, crude fibre and metabolisable energy were higher in the latter system. Semi-scavenging (1.3 ± 0.05kg) carcasses were heavier (P<0.05) than full scavenging ones (1.0 ± 0.06kg). The ultimate pH (24h) (pHu) of meat from full scavenging chickens (6.0 ± 0.03) was higher (P<0.05) than that of meat from the semi-scavenging chickens (5.7 ± 0.04). Meat from the full scavenging chickens had higher L* values (60 ± 1.2) than meat from the semi-scavenging chickens (47 ± 0.8). The a* value of meat of full scavenging chickens was significantly (P<0.05) less (4 ± 0.4) than that of meat from semi-scavenging chickens (15 ± 1.3). There was a significant positive (0.60) correlation between pHu and L* of meat from village chickens across rearing systems. The semi-scavenging system meat had better sensory attributes than the meat from the full scavenging system. Female consumers scored the typical flavour of village chicken meat across rearing systems higher (P< 0.05) than male consumers. The Shona consumers scored the meat higher (P< 0.05) than the Xhosa, Zulu, Ndebele and other tribes for initial juiciness, first bite impression and muscle fibre and tenderness of the chicken across rearing systems. Consumers scored of the meat from the semi-scavenging system higher (P<0.05) on initial juiciness (4.3 ± 0.20), first bite impression (4.2 ± 0.197), muscle fibre tenderness (4.5 ± 0.217) than meat from the full scavenging chickens. There were positive correlations (0.46) between aroma intensity and overall flavour intensity across both rearing systems. The semi-scavenging system produced better carcass characteristics, lighter (L*) meat and more consumer acceptable meat than full scavenging chickens. Therefore the full scavenging rearing system had better nutrient composition in its scavenging feed resource base, although the semi-scavenging systems produced chickens with better carcass, meat pH, colour and sensory characteristics than the full scavenging chickens.
- Full Text:
- Date Issued: 2012
Effect of stage of lactation on milk yield, somatic cell counts, mineral and fatty acid profiles in pasture-based Friesian, Jersey and Friesian × Jersey cows
- Authors: Nantapo, Carlos Wyson Tawanda
- Date: 2012
- Subjects: Trace elements in animal nutrition , Genotype-environment interaction , Milk yield -- Testing , Lactation , Holstein-Friesian cattle , Jersey cattle
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11819 , http://hdl.handle.net/10353/d1006810 , Trace elements in animal nutrition , Genotype-environment interaction , Milk yield -- Testing , Lactation , Holstein-Friesian cattle , Jersey cattle
- Description: The effect of stage of lactation on milk yield, somatic cell counts, mineral and fatty acid profiles in pasture-based Friesian, Jersey and Friesian × Jersey cows was investigated. Twenty Friesian, twenty Jersey and twenty Friesian × Jersey cows were randomly selected from a dairy herd. A total of 202 milk samples were collected and analysed in three stages of lactation. Genotypic differences were observed in milk yield and fat content. Friesian cows produced the highest yield and lowest fat content whereas the opposite was true for Jersey cows (P<0.01). No significant differences were observed in SCC in the different genotypes, but SCC levels were higher in mid and late lactation (P<0.001). There was no effect (P<0.005) of genotype and stage of lactation interaction on Ca, P, Mg, Na, Mn and Bo concentration. Jersey cows had the least concentration of Fe and Cu in all stages of lactation. Strong positive correlations were observed among Ca and P, Mg and Zn. Aluminium had a strong positive relationship with Bo, Fe, Mn and Zn (P<0.001). Generally, SCC had a weak positive relationship with macro elements but a significant negative relationship with microelements. Yield levels were negatively correlated with Mg, Na, Al, Mn and SCC. Pasture ALA, SFA, n-3, n-6/n-3 and PUFA/MUFA concentration did not differ across the study period. Linoleic acid was highest in the second phase which coincides with mid lactation in cows (P<0.001). Highest moisture content coincided with the least fat free dry matter content in early lactation (P<0.001). Significantly high fat content was observed in late lactation than in early lactation. Highest butyric, caproic, linoleic, n-6 and PUFA were observed for Friesian cows. All other fatty acids ratios were not significantly different among different genotypes. Highest CLA, ALA, LA, SFA, PUFA, n-6, and n-3 and atherogenicity index were observed in early lactation whereas desaturase activity indices were highest in late lactation. Strong positive correlations were observed among milk vaccenic, ALA, LA and CLA concentrations. Inverse relationships were observed between SFA and long chain fatty acids. It can be concluded, it may be of advantage to consume milk from early stage of lactation poses a lower risk to coronary diseases and are much safer to consume.
- Full Text:
- Date Issued: 2012
Effects of feeding Moringa Oleifera leaf meal as an additive on growth performance of chicken, physico-chemical shelf-life indicators, fatty acid profiles and lipid oxidation of broiler meat
- Authors: Wapi, Cwayita
- Date: 2012
- Subjects: Moringa , Broilers (Chickens) , Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11822 , http://hdl.handle.net/10353/d1007546 , Moringa , Broilers (Chickens) , Meat -- Quality
- Description: Effects of feeding Moringa oleifera leaf meal as an additive on growth performance of chicken, physico- chemical shelf-life indicators, fatty acids profiles and lipid oxidation of broiler meat The main objective of the study was to determine the effect of M.oleifera leaf meal (MOLM) as an additive on growth performance, carcass characteristics, physico-chemical shelf-life indicators (colour, ultimate pH, driploss), fatty acids profiles and lipid oxidation of meat from broilers. A total of 432 1day old unsexed broiler chicks (Aviane 48) were randomly allocated to four dietary treatments (TRTS) in 72 cages. There were 18 cages per treatment and each cage allocated 6 chicks. Water and feed was provided at ad libitum. The feeding phases were, prestarter (0-7 Days), starter (8-18 Days), grower (19-28 Days), finisher (29-35 Days). The four TRTS contained graded levels of MOLM at 1000g/ton, 750g/ton, 500g/ton, and 0g/ton (control), respectively. The birds were slaughtered at 35 days of age. Breast muscles were sampled for meat, ultimate pH (pHu ), colour, drip loss over a 7 days shelf-life test. After each day’s test sub-samples were dipped in liquid nitrogen and kept at -180 C for thiobarbituric acid reactive substances determination. On Day1 and Day 7 extra sub-samples were also kept at -180 C for fatty acids analysis.The TRTS had no effect on average feed intake (AFI), feed conversion efficiency (FCE), and on average daily gain (ADG). Slaughter weight (SW), carcass weight (CW), dressing percentage and gizzard weight (GW) values were similar in all TRTS. Liver weight (LW), heart weight (HW), and gastro-intestinal fat (GIF) differed in all the TRTS, with treatment 2 having the highest value of HW (28.3±2.55), and LW (44.2±1.60) was the highest on treatment 4 . The pH values in all TRTS were constant from Day1 to Day5, reached peak on Day6, and then declined on Day7. Meat from broilers given treatment 1 with MOLM (1000g/ton) had the highest lightness (L*) values. The redness (a*) values were the highest in meat from treatment 2 (750g/ton MOLM). Treatments had no effect on yellowness (b*) values and on drip loss of the breasts. During storage L* values were high from Day1 to Day5 and decreased from Day6 to Day7. Drip loss increased with storage time as expected. Treatment 4 (control) had the highest proportions of poly-unsaturated fatty acids (PUFA) (30.3±1.87). Treatment 1 (1000g/ton) had the highest proportion of saturated fatty acids (SFA) (60.9±1.87). Treatment 1 (1000g/ton) had the highest proportion of SFA (60.9±4.30). Treatment 2 (750g/ton) had the highest n-6/n-3 ratio than other TRTS. Days had no effect (P>0.05) on PUFA, SFA, and n-6/n-3 ratio. Treatment 1 had a highest amount of malondialdehyde (MDA), treatment 4 had no effect (P>0.05) on MDA . Storage time had an effect (P<0.05) on MDA levels, except for on Day1 and Day7. Day2 had the highest amount of MDA (0.7±0.08). The use of MOLM as an additive in broiler diets reduced lipid oxidation in meat, and maintained the quality of the broiler meat during storage. It also did not have any adverse effects on the growth performance of broilers. Therefore, it has the potential to be used as an additive in broiler diets.
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- Date Issued: 2012
Effects of pre-slaughter sheep handling and animal-related factors on creatine kinase levels and physico-chemical attributes of mutton
- Authors: Chulayo, Amanda Yucca
- Date: 2012
- Subjects: Sheep -- South Africa , Mutton , Slaughtering and slaughter-houses -- South Africa , Creatine -- Physiological effect
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11810 , http://hdl.handle.net/10353/433 , Sheep -- South Africa , Mutton , Slaughtering and slaughter-houses -- South Africa , Creatine -- Physiological effect
- Description: Effects of pre-slaughter sheep handling and animal-related factors on Creatine Kinase levels and physico-chemical attributes of mutton By Chulayo Amanda Yucca The objective of the study was to determine the effects of pre-slaughter sheep handling and animal-related factors on Creatine kinase (CK) levels and physico-chemical characteristics of mutton from South African sheep breeds. One hundred and seventy-three castrated male sheep from four breeds (15 Dormer, 46 South African Mutton Merino, 77 Dorper and 35 Blackhead Persian) were used. The animals were grouped according to age categories. The grouping was as follows: Group 1 (6 ≤ 8 months), Group 2 (9 ≤ 12 months) and Group 3 (13 ≤ 16 months). Blood samples for CK determination were collected at exanguination using disposable vacutainer tubes. Representative samples of the Muscularis longissimuss thoracis et. lumborum (LTL) muscle were taken for the determination of ultimate pH (pHu), colour (L*-lightness, b*- redness and a*- yellowness), thawing and cooking losses and meat tenderness. Significant (P<0.01) breed effects were observed on CK levels with Dormer having the highest CK values. Significant linear relationships were observed between pre-slaughter condition and CK levels. There were positive correlations between colour coordinates L* and b* (r =+0.22) and between a* and b* (r =+0.63). Cooking loss and Warner Braztler Shear Force (WBSF) values were positively correlated (r =+0.29). The Principal Component Analysis (PCA) showed a significant variance for CK and between physico-chemical characteristics of mutton. There were no relationships between CK levels and physico-chemical characteristics of mutton. Significant breed and age effects on pHu, L, a*, b*, thaw %, CL and WBSF of mutton were observed. iv It was concluded that, pre-slaughter conditions affect CK levels and physico-chemical characteristics of mutton. However, there were no relationships between CK levels and physico-chemical characteristics of mutton.
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- Date Issued: 2012