Determination of acaricide resistance profiles, and geographic range of boophilid Rhipicephalus tick spp. (Acari: Ixodidae), and sero-status of tick-borne pathogens on communal cattle in the north-eastern regions of the Eastern Cape Province, South Africa
- Authors: Yawa, Mandla https://orcid.org/0000-0002-2402-298X
- Date: 2021-09
- Subjects: Cattle -- Diseases , Ticks as carriers of disease , Ticks
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/21590 , vital:49356
- Description: Cattle industry improves livelihoods for many developing farmers in South Africa, however, ticks and tick-borne diseases (TBDs) pose a detriment impact on cattle success; this is due to their resistance to acaricide application. Thus, this study was conducted to determine the extent of acaricide resistance, serostatus of tick-borne pathogens, and geographic range of boophilid ticks in communal grazing cattle in the north-eastern regions of the Eastern Cape Province (ECP), South Africa. A total of 160 structured questionnaires were prepared and randomly administered to cattle farmers to investigate their knowledge, attitudes, and practice on ticks and TBDs affecting cattle, tick control methods used, and their knowledge of acaricide resistance. Engorged visible cattle ticks were collected seasonally from 10 randomly selected cattle from the community cattle herds during dipping days between October 2018 and September 2019, and stored into the labelled test tubes containing 70 percent ethanol. For TBDs determination, a total of 240 cattle from Elundini and Senqu Municipalities were seasonally used to investigate the prevalence of ticks and TBDs, packed cell volume (PCV), and body condition scores (BCS). Shaw Larval Immersion Test (SLIT) method was used to determine the resistance of Rhipicephalus decoloratus larvae to various acaricides such as amidines, organophosphate, and synthetic pyrethroids. This study indicates that approximately 59 percent of the interviewed cattle farmers had no knowledge of the effect of TBDs affecting cattle production, and 78 percent of respondents considered ticks are the major challenge to the success of their cattle farming. Pour-on (61 percent) was the most commonly used acaricidal treatment system with fortnightly (40 percent and 31percent) treatment frequencies during the summer and winter seasons respectively. Synthetic pyrethroids (73 percent) were the most used acaricide compounds to control ticks. Moreover, approximately 85 percent of respondents perceived that they do not practice acaricide rotation, and 88 percent of the respondents had no knowledge of acaricide resistance. Interestingly, the current study record Rhipicephalus microplus for the first time at Elundini, Senqu, and Walter Sisulu. Based on the morphological traits, a total of 6176 ticks belonging to two boophilid tick species of Rhipicephalus were identified: R. decoloratus (98 percent) and R. microplus (2 percent). Rhipicephalus decoloratus was significantly higher (P<0.05) in Elundini during the hot-dry (3.37±0.121) and hot-wet (3.35±0.121) seasons compared to other localit ies. In Senqu, R. microplus had high counts (P<0.05) during the post-rainy season (1.06±0.027) compared to other localities. From this present study, it was observed that Ehrlichia ruminantium was the most prevalent at Elundini (16 percent) and (14 percent) during post-rainy and hot-dry seasons respectively and 15 percent at Senqu during the post-rainy season. Babesia bigemina was more frequent at Elundini (18 percent) and Senqu (16 percent) during the post-rainy season and hot-wet season, respectively. Cattle BCS were significantly negatively correlated with E. ruminantium (P<0.01; r = -0.203), B. bovis (P<0.01; r = -0.125), and A. marginale (P < 0.01; r = -0.122). On the other hand, PCV was significantly negatively correlated with B. bigemina (P<0.01; r =-0.138). E. ruminantium was strongly positively correlated with Amblyomma hebraeum (P<0.05; r = 0.112), while B. bovis (P<0.05; r = 0.134) and B. bigemina (P<0.05; r = 0.188) were strong positively correlated with Rhipicephalus microplus infestation and B. bigemina (P<0.05; r = 0.077) with Rhipicephalus decoloratus. During acaricide resistance testing, Shaw Larvae Immersion Testing (SLIT) was only performed on R. decoloratus larvae as engorged R. microplus ticks could not meet the required sample size for resistance testing. The current study found that the majority of the tick were susceptible at exposure to differe nt acaricide field concentrations of amidines (49 percent at 250ppm), organophosphates (33 percent and 47 percent at 300ppm and 500ppm, respectively), and synthetic pyrethroids (44 percent and 23 percent at 150ppm and 300ppm, respectively). In conclusion, less knowledge of cattle farmers on the threat pose by ticks on their cattle production results in the spatio-temporal spread of boophilid tick from region to region and from season to season thus increases incidence and risk for tick resistance. , Thesis (PhD) -- Faculty of Science and Agriculture, 2021
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- Date Issued: 2021-09
An investigation of Borrelia burgdorferi in South Africa
- Authors: Nurton, Jane Patricia
- Date: 1993
- Subjects: Ticks , Ticks as carriers of disease , Borrelia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5722 , http://hdl.handle.net/10962/d1005408 , Ticks , Ticks as carriers of disease , Borrelia
- Description: Four commonly occurring genera of ticks in South Africa were tested for their capacity to acquire and transmit Borrelia burgdoiferi, the causative agent of Lyme disease. Attempts were made to infect rabbits with a culture of B. burgdoiferi, and tick transmission experiments were carried out using the rabbits as the host of infection. Only one rabbit was successfully infected. Histological changes associated with a B. burgdoiferi infection were noted in this rabbit, but no spirochaetes were isolated. All other host animals failed to become infected with the B. burgdoiferi. As a consequence transmission experiments with the local ticks failed. Serological surveys conducted on rodents, horses and cattle using immunofluorescent and haemagglutination tests indicated that there is evidence that Borrelia species occur widely and that there is a possibility of B. burgdoiferi occurring in South Africa. Studies conducted on ticks from suspected endemic areas revealed the presence, in Ixodes bakeri only, of a spirochaete-like organism that reacted with monoclonal antibody H5332. Shortcomings of the study are highlighted and proposals are presented to address the problem of identifying specific B. burgdoiferi infections.
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- Date Issued: 1993