Studies were conducted to determine some of the characteristics of the spring rise in faecal shedding of nematode ova by parasitized ewes in the Montreal area. [...]

Thesis (MSc (Veterinary Tropical Diseases.))--University of Pretoria, 2008. / Includes bibliographical references. Also available in print format.

Thesis (MSc. (Veterinary Tropical Diseases, Veterinary Science))--University of Pretoria, 2000. / Also available in print format.

No description available.

Made available in DSpace on 2016-03-07T19:21:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-04. Added 1 bitstream(s) on 2016-03-07T19:25:24Z : No. of bitstreams: 1 000859463.pdf: 763561 bytes, checksum: 71b45b72b48b91462234eb648d259abd (MD5) / O objetivo foi identificar diferentes categorias de animais dentro de um rebanho de novilhas da raça nelore de acordo com seu grau de infecção por helmintos, correlacionando dados de exames coproparasitológicos, hematológicos, sorológicos e desempenho produtivo, de modo a avaliar a diferença entre as categorias de infecção destes animais. Foram avaliadas 100 fêmeas da raça Nelore, com média de oito meses de idade. Foram avaliadas: análise coproparasitológica, análise sanguínea para alterações hematológica, análise sorológica para níveis de IgG, mensurações da espessura de gordura subcutânea e desempenho. Os animais foram identificados em três grupos de acordo com seu grau de infecção por helmintos: resistentes, resilientes ou susceptíveis. Os dados foram analisados com o auxilio do Software BioStat, versão 5. Os animais resistentes desmamaram mais pesados. Quando analisado o período sazonal existe menor ganho de peso dos animais susceptíveis na época das águas. O grupo susceptível se mostrou menor para volume globular. Conclui-se que os animais susceptíveis se mostraram mais acometidos pelo gênero Haemonchus spp. e Oesophagostomum spp., tendo uma redução do volume globular. Todas as categorias apresentaram um desempenho produtivo semelhante ao longo do experimento, porém em função da sazonalidade apenas os animais susceptíveis foram influenciados. Levando em consideração que os indivíduos susceptíveis abrigam um maior número de nematódeos gastrintestinais, a seleção desses animais seria boa alternativa para reduzir o uso de anti-helmínticos / The objective was to identify different categories of animals inside a Nellore heifers herd according to their degree of helminth infection, correlating data from fecal examinations, hematological, serological and productive performance in order to evaluate the difference between the categories of infection of these animals. 100 Nellore females were evaluated, averaging eight months old. Were evaluated: coproparasitological analysis, blood test for hematologic changes, serological analysis for IgG levels, measurements of fat thickness and performance. The animals were identified in three groups according to their degree of helminth infection: resistant, resilient or susceptible. Data were analyzed with the help of BioEstat Software, version 5. The animals resistant weaned heavier. When analyzed the seasonal period there is less weight gain of susceptible animals during the rainy season. The group proved less likely to packed cell volume. We conclude that the animals which were more affected by gender Haemonchus spp. and Oesophagostomum spp., with a decrease in cell volume. All categories showed a similar growth performance during the experiment, but due to the seasonality only animals susceptible were influenced. Taking into account that the susceptible individuals harbor a larger number of gastrointestinal nematodes, the selection of these animals would be a good alternative to reduce the use of anti-helminthic

Orientador: Ricardo Velludo Gomes de Soutello / Banca: Ricardo da Fonseca / Banca: Alessandro Francisco Talamini do Amarante. / Resumo: O objetivo foi identificar diferentes categorias de animais dentro de um rebanho de novilhas da raça nelore de acordo com seu grau de infecção por helmintos, correlacionando dados de exames coproparasitológicos, hematológicos, sorológicos e desempenho produtivo, de modo a avaliar a diferença entre as categorias de infecção destes animais. Foram avaliadas 100 fêmeas da raça Nelore, com média de oito meses de idade. Foram avaliadas: análise coproparasitológica, análise sanguínea para alterações hematológica, análise sorológica para níveis de IgG, mensurações da espessura de gordura subcutânea e desempenho. Os animais foram identificados em três grupos de acordo com seu grau de infecção por helmintos: resistentes, resilientes ou susceptíveis. Os dados foram analisados com o auxilio do Software BioStat, versão 5. Os animais resistentes desmamaram mais pesados. Quando analisado o período sazonal existe menor ganho de peso dos animais susceptíveis na época das águas. O grupo susceptível se mostrou menor para volume globular. Conclui-se que os animais susceptíveis se mostraram mais acometidos pelo gênero Haemonchus spp. e Oesophagostomum spp., tendo uma redução do volume globular. Todas as categorias apresentaram um desempenho produtivo semelhante ao longo do experimento, porém em função da sazonalidade apenas os animais susceptíveis foram influenciados. Levando em consideração que os indivíduos susceptíveis abrigam um maior número de nematódeos gastrintestinais, a seleção desses animais seria boa alternativa para reduzir o uso de anti-helmínticos / Abstract: The objective was to identify different categories of animals inside a Nellore heifers herd according to their degree of helminth infection, correlating data from fecal examinations, hematological, serological and productive performance in order to evaluate the difference between the categories of infection of these animals. 100 Nellore females were evaluated, averaging eight months old. Were evaluated: coproparasitological analysis, blood test for hematologic changes, serological analysis for IgG levels, measurements of fat thickness and performance. The animals were identified in three groups according to their degree of helminth infection: resistant, resilient or susceptible. Data were analyzed with the help of BioEstat Software, version 5. The animals resistant weaned heavier. When analyzed the seasonal period there is less weight gain of susceptible animals during the rainy season. The group proved less likely to packed cell volume. We conclude that the animals which were more affected by gender Haemonchus spp. and Oesophagostomum spp., with a decrease in cell volume. All categories showed a similar growth performance during the experiment, but due to the seasonality only animals susceptible were influenced. Taking into account that the susceptible individuals harbor a larger number of gastrointestinal nematodes, the selection of these animals would be a good alternative to reduce the use of anti-helminthic / Mestre

Please read the abstract in the section 00front of this document / Dissertation (MSc (Veterinary Science))--University of Pretoria, 2000. / Veterinary Tropical Diseases / unrestricted

Nematode parasites have become the biggest problem for small ruminant production in South Africa due to their resistance to the commercial anthelmintics. Notable, wattle tannin has been used as an alternative strategy for control. However, the concentration and the frequencies can likely influence its effect on the parasites control. The objective of this study was to determine the degree of pasture infestation and nematode infection in sheep and goats, as well as investigate nematode resistance to the anthelmintics, and the potential of wattle tannin in nematode control. The first study dealt with the epidemiology of internal parasites. Eight Merino ewes and eight Nguni does averaged 7-18 months of age were observed for 1 year during the months of February 2008 to January 2009 at the University of KwaZulu-Natal Research Farm (Ukulinga). Egg count per gram (EPG) and coccidian oocysts per gram (OPG) were counted according to Mc Master Technique (Hansen & Perry, 1994) by magnifying parasitic eggs from monthly rectal faecal samples dissolved in saturated sodium chloride. Faecal samples also were cultured for 15 days to identify infective nematode larvae (L3) using Baermann technique. Herbage samples were collected monthly from four paddocks as well to count L3 on the pasture. Sheep live weight was also recorded monthly. Seasonal effects was significant (P<0.05) on the EPG, OPG, faecal culture L3 and pasture L3. A higher level of infection was observed in summer (wet) than in winter (dry season). Trichostrongylus spp larvae were the most prevalent larvae (26.5%) while Strongyloides, Haemonchus contortus, Nematodirus and Cooperia spp occurred in the faecal culture by percentage of 20.9%, 16%, 16% and 14.5%, respectively. For parasite resistance, Ivermectin 1% (IVM), Closantel 5% (CST) and a combination of Abamectin 0.08% and Praziquantel 1.5% (CPA) were evaluated. Twenty four sheep (12 females and 12 males) aged between 7-18 months were used for 21 days. Animals were naturally infested by gastro-intestinal parasites. EPG and faecal culture L3 were counted on day 0, 7, 14 and 21. Closantel was the most effective. Haemonchus spp. were least affected whilst Trichostrongylus spp. were the most affected by all drugs. In the third study, wattle tannins were evaluated as an alternative nematode control drug. Three experiments (Exp.) were conducted to determine the effect of tannin concentration (Exp.1 and 2) and frequency (Exp.3) on nematode parasites. In Exp.1, 0, 0.8, 1.6 and 2.4 g tannin/kg BW were drenched for three consecutive days per sheep (16 females and 8 males, aged 8-9 months) for 21 day. In Exp.2, 30 sheep (14 males and 16 females, aged 9-18 months) were randomly allocated into three tannin treatments (0, 0.8 and 1.6 g tannin/kg BW) and drenched for a day. In Exp.3, 26 sheep (11 males and 15 females aged 9-18 months) were divided into three groups of 9, 9, and 8 sheep each. These groups were drenched with 1.6 g tannins/kg BW/day; once, twice or thrice for the 3 groups respectively. For the three experiments, EPG and L3 larvae were counted in individual feacal samples. For all tannin treatments, EPG decreased (P<0.05) over time. Though the differences among tannin levels and frequencies varied (P<0.05) over time, EPG consistently decreased with increasing tannin level and frequency. Thus 1.6 and 2.4 g tannin /kg BW for 3 consecutive days had nearly similar effects on the EPG. The results of this study are rather inconclusive that weather conditions such as rainfall had a direct effect on internal parasites development. Nematode parasites at Ukulinga Research Farm were resistant to the commercial anthelmintics used. Drenching with 1.6g wattle tannin/kg BW over three successive days is enough to reduce EPG and reduce the degree of pasture contamination. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

No abstract available

Thesis (M.Sc.) - University of KwaZulu-Natal, Pietermaritzburg, 2010. / Full text also available online. Scroll down for electronic link.