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.

Tyrimo metu buvo nustatinėjama dviejų dehelmintizavimo programų efektyvumas šunų virškinimo trakto helmintų kontrolei tam panaudojant kombinuotą antihelmintiką (Milbemicino oksimas/prazikvantelis). Tyrimas buvo atleikamas kaimo vietovėse, kurios nuo Kauno nutolusios per 50 – 100 km. Pasiruošimo metu iš viso buvo surinkta 455 šunų. Tyrimo metu (5 mėnesių laikotarpis) kiekvieną mėnesį buvo renkami šunų išmatų mėginiai. Visi mėginiai buvo tiriami Lietuvos sveikatos mokslų universitete, Veterinarijos akademijoje, Užkrėčiamų ligų katedros laboratorijose remiantis flotacijos/sedimentacijos metodu pagal Ciūricho universiteto parazitologijos instituto metodiką. Gautų rezultatų duomenimis, nustatytas 74,1 – 100 proc dehelmintizavimo programų efektyvumas. Tirti šunys buvo užsikrėtę Taeniidae cestodais (2,0 proc.) Toxocara canis (3,3 proc.), Toxascaris leonina (0,7 proc.), Uncinaria stenocephala (22,6 proc.), Capillaria putorii (0,7 proc.) ir Trichuris vulpis (0,9 proc.) helmintais. Gausiausiai šunys buvo užsikrėtę U. Stenocephala nematodais - 103 iš 455, kas sudaro 22,6 proc. visų tirtų šunų ir 66 proc. visų bendrai apsikrėtusių šunų. I – osios programos efektyvumas (2 dehelmintizacijos), panaudojus kombinuota antihelmintiką (milbemicino oksimas/prazikvantelis) buvo nuo 73,1 iki 100 proc. Tuo tarpu II – osios programos efektyvumas (1 dehelmintizacija) buvo 74,2 – 100 proc. Magistiniame baigiamajame darbe pateikta 12 lentelių, 1 žamėlapis ir 1 diagrama. / In this study the effectiveness of two helmintic programs for the gastrointestinal helminthes control in dogs by using an combied anthelmintic (milbemycin oxime/praziquantel) was studied. The examination was conducted in rural areas, which were located 50 – 100 km around Kaunas. During the preparation period, there were 455 dogs collected. Throughout a five month investigation period, dog feces were collected monthly intervals. Fecal samples were examinated using flotation/sedimentation technique modified in Institute of Parasitology, University of Ziurich. Considering the given results, 74,1 – 100 % efficiency of anthelmintics programs was established. The dogs were infected with Taeniidae tapeworms (2,0%), Toxocara canis (3,3%), Toxascaris leonine (0,7%), Uncinaria stenocephala (22,6%), Capillaria putorii (0,7%) and Trichuris vulpis (0,9%). Most of the dogs were infected by U. Stenocephala tapeworms – 103 dogs out of 455, which is 22,6 % of all examined dogs and 66 % of dogs, which were generally infected. The treatment with combination of anthelmintics (milbemycin oxime/praziquantel) at dosing rate of double treatment (I program) was effective reducing infection with 73,1 – 100 percent. Meanwhile single treatment control program (II program) was effective reducing infection with 74,2 – 100 percent. This Masters thesis contains twelve charts, one map and one diagram.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2004. / Härtill 4 uppsatser.

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

Orientador: Silmara Marques Allegretti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T03:25:23Z (GMT). No. of bitstreams: 1 Medeiros_PaulaBernaSilva_M.pdf: 8441306 bytes, checksum: c8227b5d6161dcf60e495b4bb986d125 (MD5) Previous issue date: 2014 / Resumo: A estrongiloidíase é uma parasitose negligenciada de difícil controle, principalmente pela sua capacidade de autoinfecção, por responder de forma irregular à terapêutica e pelo risco de hiperinfecção. O tratamento envolve fármacos como benzimidazois e ivermectina. Contudo, estes não apresentam uma resposta homogênea no combate à doença. Nesse contexto, surge a necessidade de novas opções para o tratamento desta parasitose, sendo uma alternativa viável o uso de plantas medicinais. A espécie Spondias lutea, árvore frutífera comumente chamada por "cajazeiro", foi avaliada neste estudo a fim de identificar possível propriedade terapêutica no tratamento desta parasitose. Neste estudo foram testados o extrato etanólico e frações de S. lutea in vitro sobre fêmeas parasitas de Strongyloides venezuelensis, nas concentrações de 0,4 mg/mL, 0,2 mg/mL, 0,1 mg/mL e 0,05 mg/ mL. Todas as amostras foram solubilizadas em PBS e em seguida as análises foram repetidas para posterior comparação de resultados com a inclusão de polivinilpirrolidona (PVP) junto às amostras como um agente facilitador da solubilização. As observações foram realizadas em intervalos crescentes entre 2 - 72 horas após incubação em estufa de atmosfera de CO2- 5% a uma temperatura de 37°C, utilizando placas de cultura de 24 poços, em meio RPMI acrescido penicilina (10.000 UI/L) e estreptomicina (0,05 g/L). Foram observados os parâmetros motilidade e mortalidade dos parasitas. O estudo constatou que a fração 4 apresentou o melhor resultado atingindo 67% de mortalidade na maior concentração avaliada após 2 horas de incubação e atingindo 100% após 4 horas de incubação na mesma concentração. Observou-se ainda 100% de mortalidade nas concentrações 0,2 mg/mL e 0,1 mg/mL após 12 horas de incubação e 100% de mortalidade com 24 horas de incubação em todas as concentrações avaliadas. A ivermectina não ocasionou a morte dos vermes em nenhuma das concentrações testadas, observando-se discreta redução de motilidade dentro do período estudado / Abstract: Strongyloidiasis is a neglected parasitosis whose control is very difficult, especially because of its ability to auto-infect, by the irregular response to therapeutic and for the risk of hyperinfection. Treatment involves drugs such as benzimidazoles and ivermectin. However, these drugs do not present a homogeneous response against the disease. In this context it is important to look for new alternatives in the treatment of this disease and one is the use of medicinal plants. Spondias lutea, commonly called as cajazeiro fruit tree species was evaluated in this study in order to identify possible therapeutic properties in the treatment of this disease. In this study, the ethanol extract and fractions of S. lutea were tested in vitro against parasitic females of Strongyloides venezuelensis at concentrations of 0.4 mg/mL, 0.2 mg/mL, 0.1 mg/mL and 0.05 mg/ml. All samples were solubilized in PBS and then analyses were repeated for comparison of results with the inclusion of the samples with polyvinylpyrrolidone (PVP) as a solubilization facilitator. The observations were made at increasing time intervals between 2-72 h after incubation in CO2 greenhouse at 5% and 37°C. Motility parameters and mortality of parasites were observed. The study found that the sample F4 showed the best result, reaching 67% mortality at the highest concentration evaluated after 2 hours of incubation, reaching 100% after 4 hours of incubation in the same concentration. There was 100% of mortality at the concentrations 0.2 mg/ml and 0.1 mg/ml after 12 hours incubation and 100% mortality after 24 hours of incubation at all concentrations evaluated. Ivermectin did not cause the death of the worms in any of the tested concentrations. There was only slight decrease of motility within the study period. OBSERVAÇÃOPalavras em itálico: in vitro, Strongyloides venezuelensis e Spondias lutea / Mestrado / Relações Antrópicas, Meio Ambiente e Parasitologia / Mestra em Biologia Animal

<p align="justify">Dans les pays en voie de développement et plus particulièrement en Afrique, la médecine traditionnelle est parfois la seule source de soins abordable et accessible,surtout pour les patients les plus pauvres.</p><p><p align="justify">Le présent travail a été réalisé dans le but de rechercher les preuves scientifiques de l’activité anthelminthique des extraits d’amandes de Balanites aegyptiaca utilisés en médecine traditionnelle africaine et d’évaluer une activité potentiellement anti-tumorale du ou des principe(s) actif(s) responsable(s) de l’activité anthelminthique.</p><p><p align="justify">Pour caractériser l’activité nématocide des extraits des amandes de Balanites aegyptiaca,nous avons tout d’abord mis au point un test d’évaluation de l’activité toxique en tenant compte des limitations des tests existants. La validation pharmacologique (mesurant la sélectivité, la linéarité, l’exactitude et la précision) a consisté en la détermination de l’activité nématocide d’anthelminthiques couramment utilisés. Pour la caractérisation de l’activité nématocide des amandes de Balanites aegyptiaca, puis le fractionnement, l’isolement et la purification de(s) agent(s) nématocide(s) nous avons adopté la stratégie du fractionnement bio-guidé. Les résultats obtenus montrent que le produit isolé (déterminé comme étant la balanitine-7 ou Bal-7) induit une activité toxique plus élevée sur les vers adultes que sur les stades larvaires.</p><p><p align="justify">Bal-7 s’est avéré moins toxique que le levamisole, le mébendazole et le thiabendazole, mais plus toxique que le pyrantel, le niclosamide et la pipérazine. La présente étude a donc permis de montrer que les amandes de Balanites aegyptiaca, utilisée en médecine traditionnelle au Burkina Faso, pourraient être efficaces dans le traitement des parasitoses intestinales.</p><p><p align="justify">Certains anthelminthiques comme les benzimidazoles, du fait de leur activité d’inhibition de la polymérisation des tubulines, présentent une activité anti-tumorale. Aussi, faisant suite à la mise en évidence de l’activité nématocide de Bal-7 nous avons entrepris de caractériser l’activité anti-tumorale de balanitines. La méthode d’extraction que nous avons utilisé pour évaluer l’effet anti-tumoral de la Bal-7 est distincte de celle que nous avions utilisée pour évaluer l’effet anthelminthique de cette balanitine. Ainsi, alors que la méthode d’extraction que nous avons utilisée pour obtenir de la Bal-7 pour nos tests liés à l’activité anthelminthique semble avoir conduit à l’isolement de la balanitine-7 pure, la méthode d’extraction que nous avons utilisée pour observer les effets anti-tumoraux potentiels de cette balanitine-7 nous ont conduit à isoler un mélange de balanitine-6 et de balanitine-7 dans des proportions de 28/72%. Nous avons dénommé ce mélange Bal-6/7. L’activité anti-tumorale a été évaluée sur deux lignées cancéreuses humaines (A549, cancer du poumon non-à-petites cellules et U373, glioblastome). Dans ce travail, nous avons montré que Bal-6/7 induit la mort des cellules tumorales par une déplétion marquée de l’[ATP]i et une désorganisation majeure du cytosquelette d’actine. In vivo, Bal-6/7 a montré une activité anti-tumorale modeste, mais néanmoins statistiquement significative. A ce jour, il n’existe pas sur le marché, d’anti-cancéreux dirigé contre les filaments d’actine. Etant donné le rôle de ces filaments d’actine dans la prolifération et la migration des cellules tumorales, le développement de médicaments ayant cette protéine pour cible constituerait une avancée majeure dans la recherche de nouvelles thérapies anti-tumorales. Le mélange Bal-6/7, isolé pour la caractérisation de l’activité anti-tumorale des balanitines, du fait de son potentiel anti-tumoral, présente donc un intérêt certain en thérapeutique anti-cancéreuse. Il serait donc envisageable de développer par synthèse ou hémisynthèse des dérivés de balanitines présentant un meilleur index thérapeutique que le mélange Bal-6/7.</p> / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished

Orientador: Rosangela da Silva Laurentiz / Resumo: O estudo sobre o uso de plantas e metabolitos secundários tem sido uma das alternativas mais estudadas nos últimos anos como forma de controlar a parasitose em ovinos provocada principalmente pelo nematoide Haemonchus contortus. A Piper cubeba é uma pimenta asiática que apresenta uma série de propriedades biológicas, incluindo atividade antiparasitária, sendo essa atividade, muitas vezes atribuida às lignanas cubebina, hinoquinina e diidrocubebina, que estão presentes na planta em maior concentração. Estudos in vitro com o extrato da Piper cubeba e com as lignanas cubebina, dihidrocubebina e hinoquinina demonstraram que esses compostos apresentam importante ação contra os vários estágios do desenvolvimento de vida do nematoide Haemonchus contortus, sendo a hinoquinina a mais eficaz (CE50 = 68 μg / mL contra ovos, CE50 < 35 μg / mL contra o estágio L1 e CE50 = 0.34 μg / mL contra o estágio L3). Devido à relevância desses resultados foram então realizados estudos de docking molecular com essas lignanas com o objetivo de avaliar a ação desses compostos com as proteínas fosfoetanolamina metil transferase (FMT) e a proteína tubulina do H. contortus usando o albendazol como fármaco de referência. O estudo de docking consensual utilizou os softwares Maestro 10.1, GOLD 5.3 e Autodock 4.2. Os resultados in sílico quando comparados aos resultados in vitro, demonstraram que o mecanismo de ação da hinoquinina, que se mostrou mais ativa, pode estar relacionado à inibição, tanto da β-tubul... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The study on the use of plants and special metabolites has been one of the most studied alternatives in recent years as a way to control parasitosis in sheep caused mainly by the nematode Haemonchus contortus. Piper cubeba is an Asian pepper that has a series of biological properties, including antiparasitic activity, and this activity is often attributed to cubebin, hinokinin and dihydrocubebin lignans, which are present in the plant in greater concentration. In vitro studies with the Piper cubeba extract and with the lignans cubebin, dihydrocubebina and hinokinin demonstrated that these compounds present important action against the several stages of the development of life of the Haemonchus contortus, being the hinokinin the most effective (EC50 = 68 μg / mL against eggs, EC50 <35 μg / mL against stage L1 and EC50 = 0.34 μg / mL against stage L3). Due to the relevance of these results, molecular docking studies were then carried out with these lignans in order to evaluate the action of these compounds with the phosphoethanolamine methyl transferase (FMT) proteins and the H. contortus tubulin protein using albendazole as a reference drug. The consensual docking study used the Maestro 10.1, GOLD 5.3 and Autodock 4.2 softwares. The in silico results when compared to the in vitro, demonstrated that the mechanism of action of hinokinin, which was more active, may be related to the inhibition of both β-tubulin and FMT-2. Although more research is needed, the results indicate tha... (Complete abstract click electronic access below) / Doutor

No description available.

Japanese yellowtail Seriola quinqueradiata has been commercially farmed in Japan since the 1940s. In comparison, sea-cage farming of yellowtail kingfish Seriola lalandi in Australia is still developing, with commercial production commencing in 1998. In Australia, S. lalandi is parasitised by Zeuxapta seriolae and Benedenia seriolae. In Japan, S. quinqueradiata is parasitised by Heteraxine heterocerca and B. seriolae. These monogeneans affect industries in both countries and management of these parasites is required to prevent impacts on fish health and commercial losses. I investigated efficacy (% reduction of mean parasite abundance) for orally administered praziquantel, fenbendzole and oxfendazole against Z. seriolae and B. seriolae on S. lalandi and the efficacy of orally administered praziquantel and febantel against H. heterocerca and B. seriolae on S. quinqueradiata. Medications were administered to fish by surface coating feed pellets or via direct intubation of the stomach. Seriola lalandi administered fenbendazole and oxfendazole by surface coating of feed had lower abundance of the gill parasite Z. seriolae. Seriola quinqueradiata intubated with febantel had lower abundance of the gill parasite H. heterocerca. Neither fenbendazole nor oxfendazole administered to S. lalandi in Australia, nor febantel administered to S. quinqueradiata in Japan resulted in a lower abundance of the skin parasite B. seriolae. Praziquantel was first administered to S. lalandi by surface coating of feed. Fish rejected medicated feed, suggesting praziquantel affected its palatability. Fish treated with feed medicated with praziquantel had fewer Z. seriolae and B. seriolae than untreated fish. Praziquantel administered to S. lalandi by intubation allowed a more accurate dose to be tested without differential feeding or reduced palatability obstructing results, and resulted in fewer Z. seriolae (99.5-100 % reduction) and B. seriolae (91 – 97.7 % reduction). Intubated praziquantel also led to fewer recruitment life stages of Z. seriolae and B. seriolae, even at low doses, but did not completely eliminate them from S. lalandi. Praziquantel administered to S. lalandi alone and combined with cimetidine had high efficacy (>99%) against Z. seriolae. In comparison, praziquantel administered alone resulted in fewer B. seriolae (68.3 – 69.7 % reduction) than the same doses of praziquantel combined with cimetidine (36.9 – 40.9 % reduction). A 90.4 -100% reduction in H. heterocerca was achieved when praziquantel was administered by intubation to S. quinqueradiata in Japan but there was only a 22-77.8 % reduction in B. seriolae. The dose of PZQ (150 mg kg⁻¹ body weight day⁻¹ for 3 days) on the label of a commercially available product used to treat B. seriolae in Japanese aquaculture resulted in a 50.9% reduction against B. seriolae, but completely eliminated H. heterocerca. In trials against Z. seriolae and B. seriolae on S. lalandi in South Australia, I also screened 27 other anthelmintics and antiparasitics from the chemical groups: amprolium derivatives, benzimidazoles, benzyl ureas, diphosphate salts, imidazothiazoles, macrocyclic lactones, nitromidazoles, organophosphates, piperazines, salicylanilides, substituted phenols and tetrahydropyrimidines. Of these, only the benzimidazole, albendazole, was effective against Z. seriolae and none appeared to have an effect against B. seriolae. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1459172 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2010

Infection of small ruminants by gastrointestinal nematodes (GIN) is a major health concern because they cause substantial economic losses, especially in the tropics and sub-tropics. For many years, control of GIN has been based upon use of anthelmintics. However, there is now a global challange because mutant GIN individuals can tolerate most of the widely used anthelmintics. Therefore, alternative control measures are needed. The objective of the study was to screen a number of plant species for their anthelmintic effects, and to evaluate selected strains of Bacillus thuringiensis (Berliner) and Clonostachys rosea (Schroers) for activity against sheep GIN. Subsequently, the combined treatments would test a dual control strategy for nematodes by using a combination of plant extracts with biocontrol agents. Ethanol extracts of 25 plant species were screened for their anthelmintic effects against Haemonchus contortus (Rudolphi 1803). Extracts of each plant were used in vitro at various concentrations (10, 20 and 30%) to treat 10 day faecal cultures. Five plants with high efficacies (Ananas comosus L. Merr., Aloe ferox Mill., Allium sativum Linn., Lespedeza cuneata Dum. Cours. and Warburgia salutaris Bertol.f. Chiov) were selected for further investigation, using ethanol, dichloromethane and water extracts at four concentrations (2.5, 5, 10 and 20%). Ethanol was the most effective solvent. Larval counts decreased as a result of increasing extract concentrations. An ethanolic extract of Lespedeza cuneata caused more than 70% mortality at all concentrations. In an in vivo study, the five plants A. comosus, A. ferox, A. sativum, L. cuneata and W. salutaris extracts were compared to a positive Control (Equimax®, a modern anthelmintic based on abamectin and praziquantel). Gender, eggs count (EPG₀) and initial body weights were used in assigning sheep (24 females and 24 males) to six groups. Each group was randomly assigned a treatment. Plant extracts were applied as an oral dose (100 mg kg⁻¹ BW), one dose per week per animal for 42 days (Phase 1). Subsequently, the same sheep were dosed for three consecutive days with the same treatments, keeping them in the same groups (Phase 2). Rectal faecal samples were taken for counting of eggs per gram of faeces (EPG) and L₃ larvae per gram (LPG) in faecal cultures. With application of plant extracts, the EPG count decreased with time (P<0.001), and the impact of the plant extracts increased (P<0.001) with time. Two extracts, from A. comosus and L. cuneata, were the most effective in Phase 1 (58% and 61% reduction of EPG, respectively,), and in Phase 2 (77% and 81% reduction of EPG, respectively). In a study on potential biocontrol agents, two strains of Bacillus thuringiensis (Bt) and one of Clonostachys rosea f. rosea (C. rosea), and compared with a diatomaceous earth (DE) product for their anthelmintic activity in sheep. Bacillus thuringiensis and C. rosea were fed to sheep at a rate of 1g kg⁻¹ BW, and DE was fed at 2% of sheep diet. The biocontrol treatments had no effect on EPG (P>0.05), but reduced GIN larvae per gram (LPG) (P<0.001) in faecal culture. Efficacy varied with time (P<0.001). By Day 7 Bt, C. rosea and DE had caused mortalities of GIN of 75.7, 86.9 and 60.6%, respectively. In addition, the efficacy of feeding 1g kg⁻¹ BW of C. rosea chlamydospores to sheep every day, every second day and every third day was tested. Daily feeding of fungal chlamydospores reduced LPG (a count of 12±1.67 GIN larvae) (P<0.001) more than feeding them the biocontrol agent every second day (39±0.77) or third day (58±1.77). By Day 12, feeding the biocontrol agent to sheep every day, every second day, or every third day caused mortality of GIN larvae of 90, 63 and 49%, respectively. Four dietary levels (treatments) of C. rosea (0.25g (F1), 0.5g (F2), 1g (F3) and control (C) of C. rosea product kg-1 BW) were tested. Treatments were each mixed with a complete diet and fed to sheep once daily for 10 weeks, according to body weights. Increased doses of the biocontrol agent reduced LPG (P<0.001), larval development (LD) (P<0.001), and increased efficacy (P<0.001). On Day 70, F1, F2, F3 and the Control controlled LD by 33.3, 72.3, 89.4 and 2.6%, respectively. Clonostachys rosea was effective in reducing third stage larvae (L₃) on pastures significantly (P<0.001) by Day 63 and Day 70. Ethanolic extracts of A. comosus, A. ferox, A. sativum, L. cuneata and W. salutaris all reduced egg production by GIN parasites of sheep. Feeding sheep cultured chlamydospores of a biocontrol fungus, Clonostachys rosea, reduced counts of nematode larvae in sheep; and 1g C. rosea chlamydospores kg⁻¹ BW daily was enough to reduce nematode infective larvae, therefore reducing the degree of pasture contamination. An initial trial showed that the combination of the two treatments of an A. comosus extract and C. rosea chlamydospores was more effective than either treatment on its own in controlling gastrointestinal nematodes in sheep. A long-term trial is being undertaken currently to confirm this finding. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.