Vet World Vol.14 February-2021 Article-1
Research Article
Veterinary World, 14(2): 302-313
https://doi.org/10.14202/vetworld.2021.302-313
Anthelmintic resistance and prevalence of gastrointestinal nematodes infecting sheep in Limpopo Province, South Africa
2. Department of Life and Consumer Sciences, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1709, South Africa.
3. Department of Epidemiology, Parasites and Vectors Programme, ARC-Onderstepoort Veterinary Research, Onderstepoort, 0110, South Africa.
4. Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, 0110, South Africa.
Background and Aim: Previous studies recorded the prevalence of gastrointestinal nematodes (GIN) in Limpopo Province. However, the studies did not address the seasonal patterns of infection and did not cover all districts of Limpopo Province, namely; Capricorn, Sekhukhune, Waterberg, Mopani, and Vhembe. It is, therefore, important to provide up to date information on the prevalence and seasonal occurrence data of GIN in all districts of Limpopo province. The present study was conducted to determine the occurrence of anthelmintic resistance (AR) and document the prevalence of GIN infecting sheep in five districts of Limpopo Province, South Africa.
Materials and Methods: Forty animals in each district were used for fecal egg count reduction test (FECRT) to determine AR against ivermectin (0.2 mg/kg), levamisole (LEV) (5 mg/kg), and albendazole (7.5 mg/kg). Egg hatch test (EHT) was used to determine AR against thiabendazole (TBZ) and micro-agar larval development test (MALDT) was used for both TBZ and LEV. Naturally, infected sheep (n=780) were sampled for prevalence across five districts of Limpopo. FAMACHA© eye-color score estimations were also performed for each study animal.
Results: FECRT showed occurrence of AR in most of the districts and a few with suspected resistance. EHT results showed AR development against TBZ for all districts, while the MALDT showed no AR against LEV in all districts, but detected AR against TBZ in Sekhukhune, Capricorn, and Waterberg. Haemonchus contortus was the most resistant species. A high nematode prevalence (88-100%) and 1210-1861 eggs per gram (EPG) was observed in all districts during the hot wet season, decreasing to 75-80% (453-1202 EPG) during the cold dry season. The sheep revealed a FAMACHA© mean score of 3, indicating mild anemia during the hot wet season except for Vhembe district that revealed a FAMACHA© mean score of 4 during the hot wet season, indicating anemia.
Conclusion: AR recorded in Limpopo Province may be due to under-dosing caused by lack of weighing equipment and high treatment frequencies due to lack of proper training on anthelmintic use. The detection of AR in Limpopo is an important finding because it will help in outlining effective management systems against GIN. Keywords: anthelmintic resistance, fecal egg counts, FAMACHA, seasonal prevalence, sheep.
Keywords: anthelmintic resistance, fecal egg counts, FAMACHA, seasonal prevalence, sheep.
How to cite this article: Mphahlele M, Tsotetsi-Khambule AM, Moerane R, Komape DM, Thekisoe OMM (2021) Anthelmintic resistance and prevalence of gastrointestinal nematodes infecting sheep in Limpopo Province, South Africa, Veterinary World, 14(2): 302-313.
Received: 30-06-2020 Accepted: 16-12-2020 Published online: 02-02-2021
Corresponding author: Morutse Mphahlele E-mail: morutse.broilerchicks@gmail.com
DOI: 10.14202/vetworld.2021.302-313
Copyright: Mphahlele, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.