Segurança clínica e atividade endoparasiticida de uma nova molécula (Aurixazol) em bovinos e ovinos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da atividade carrapaticida e anti-helmíntica do abacaxi (Ananas comosus L.) em ruminantes

Pós-graduação em Medicina Veterinária - FCAV

Efeito do genótipo e do teor protéico da dieta na resistência de cordeiros à hemoncose experimental

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Eficácia dos fungos nematófagos Duddingtonia flagrans e Arthrootrys robusta na profilaxa das infecções naturais por nematódeos gastrointestinais em ovinos

Pós-graduação em Medicina Veterinária - FMVZ

Epidemiologia das infecções por nematódeos gatrintestinais em ovinos criados em Botucatu

Pós-graduação em Medicina Veterinária - FMVZ

Sustainable worm control practices in South America

A high prevalence of nematodes, especially Haemonchus contortus and Trichostrongylus colubriformis, that exhibit multiple anthelmintics resistance has been reported in sheep in several South American countries. For this reason, the development of strategies that are less dependent on anthelmintic treatments is imperative for the prophylaxis of gastrointestinal nematode infections in small ruminants. Integrated grazing using cattle and sheep can be used for pasture decontamination with considerable reduction of H. contortus and T. colubnformis infective larvae after cattle grazing. Several breeds of sheep exhibit genetically related resistance against nematode infections, as is the case of crioulo, native or naturalised breeds of sheep. These breeds descend from livestock introduced by Portuguese and Spanish settlers and have been submitted to a long process of natural selection in various environmental conditions. In the South, the Crioula Lanada breed is more resistant to H. contortus than are Corriedale sheep. In tropical areas, where the minimum temperatures are usually higher than 20 degrees C, hair sheep flourish, especially the Santa Ines breed, which also display a higher level of resistance to nematode infections compared with certain breeds of European origin. However, Santa Ines sheep have inferior carcass quality compared with other commercial breeds. Recent studies showed that the crossbreeding of Santa Ines ewes with sires of breeds with high potential for growth and meat production, results in crossbred animals with high productivity and a satisfactory degree of resistance against nematode infections. Several studies have indicated that improvement in nutrition has a beneficial effect on the development of resistance in lambs that were naturally or artificially infected with nematodes. Therefore, supplementary feeding and breeding strategies to improve resistance to nematodes are feasible options in the effort to reduce dependence on anthelmintic drugs to control worm infections in sheep. (C) 2013 Elsevier B.V. All rights reserved.

Fauna helmintológica de ovinos provenientes da microrregião de Jaboticabal, estado de São Paulo, Brasil

This study evaluated the prevalence and counting parasitism of different species of helminths of sheep from the micro-region of Jaboticabal of Sao Paulo state. For this, 66 animals naturally infected, four to 36 months of age, raised in pasture, were selected. The results of necropsy revealed the presence of seven genera and 12 species with the following prevalence and mean count: Haemonchus contortus: 100.0% (2947.2); Trichostrongylus colubriformis: 90.9% (3048.8); Cooperia curticei: 56.0% (256.5); Oesophagostomum columbianum: 48.4% (36.0); Cooperia punctata: 30.3% (94.5); Trichostrongylus axei: 22.7% (26.5); Strongyloides papillosus: 19.6% (83.0), Haemonchus contortus (L4): 7.5% (17.2), Cooperia pectinata: 10.6% (12.9), Trichuris ovis: 10.6 % (0.6); Cooperia spatulata 4.5% (0.3); Capillaria bovis: 4.5% (0.1). The mean parasitism of helminthswas 6524.7 per animal. Haemonchus contortus (adults and L4) and Trichostrongylus colubriformis corresponded to 45.4% and 46.7% of the average worm burden totally, respectively. Based in the results obtained in this study, can be concluded that the two most abundant species of helminths and important, the micro-region of Jaboticabal are Trichostrongylus colubriformis and Haemonchus contortus, and these two species amounted to 92.1% of the distribution percentage of helminths collected from all animals. These results demonstrate the importance of conducting a counts of eggs per gram of feces (EPG) in the herds of this region when FAMACHA is used on a particular property, since this method control does not allow to diagnostic the damage/clinical signs in animals infected by T. colubriformis, because this specie does not have hematophagism habit on animals.

Prevalência de nematódeos em ovinos (Ovis aries) pertencentes a diferentes microrregiões do estado de São Paulo, Brasil

Pós-graduação em Medicina Veterinária - FCAV

Gastrointestinal nematode infections in sheep raised in Botucatu, state of Sao Paulo, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Correlações entre padrões hematológicos, parasitológicos e desempenho animal de ovelhas suplementadas com gordura protegida

The development of populations of gastrointestinal parasites resistant to antihelmintics has led to seeks new alternatives its control. Stimulation of natural immunity by means of animal nutrition has shown promising results in controlling nematodes in sheep. The addition of protected fat sources, containing essential fatty acids, may be an alternative due to many effects, among them, regulation of immunity expression and regulation of the inflammatory response by immune effectors. The aim of this study was to estimate correlations between haematological and parasitological patterns, animal performance through weight and body condition, under the influence of protected fat in ewes. Fifty Santa Ines sheep, in the final third of pregnancy or postpartum, in paddocks of Panicum maximum, received, individually, 200 g per day of concentrate, isonitrogenous and isocaloric diets, with or without the addition of protected fat. In general, except for total leukocytes and eosinophils, almost all of Pearson correlation coefficients of other variables were significant. However, the protected fat, in the amount offered, had no antihelmintic effect.

Estudo de resistência anti-helmíntica ao monepantel em propriedades de ovinos de uma microrregião em torno de Jaboticabal-SP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Parasitism by Oestrus ovis: Influence of sheep breed and nematode infections

Previous studies showed that Santa Ines (SI) hair sheep were more resistant to gastrointestinal nematode infections (GIN) than Ile de France (IF) sheep. The present experiment aimed to evaluate if that reported resistance difference against GIN also occurred against Oestrus ovis infestation and also to evaluate the influence of O. ovis infestation on the gastrointestinal nematodes (GIN) infections. SI (n = 12) and IF (n = 12) young male lambs were weaned at 2 months of age and moved to a paddock (0.3 ha) with Brachiaria decumbens grass, where they also received concentrate ration. The animals were kept together during the experimental period (September to early December 2009). Fecal and blood samples were taken from all animals every 2 weeks and body weight and nasal discharge score (oestrosis clinic signs) were recorded on the same occasion. In early December 2009, all lambs were sacrificed and O. ovis larvae and GIN were recovered, counted and identified according to the larval stage. All animals were infested by different larval instars of O. ovis without any statistical difference between breeds (P > 0.05). The SI lambs had an average of 24.8 larvae, and the intensity of infection ranged between 14 and 39 larvae, while the IF lambs showed an average of 23.5 larvae with the minimum and maximum from 11 to 36 larvae, respectively. SI lambs presented the lowest nematode fecal egg counts (FECs) and the lowest mean numbers of Haemonchus contort us, Trichostrongylus colubriformis and Strongyloides papillosus, however, there was no significant differences between group means (P > 0.05). Inverse relationship between numbers of O. ovis larvae and gastrointestinal nematodes was observed in both breeds. SI sheep showed a significant increase in blood eosinophils and total IgE serum levels and these variables were negatively correlated with nematode FEC. A negative correlation was observed between total IgE serum level and H. contortus burden in both breeds. In conclusion, there was no breed difference regarding O. ovis infestation and in each breed, animals with more nasal bot fly larvae tended to display smaller worm burden. (C) 2011 Elsevier B.V. All rights reserved.

Laser microdissection microscopy in parasitology: microscopes meet thermocyclers

The new methods of laser microdissection microscopy have received wide acceptance in biology and have been applied in a small number of parasitology investigations. Here, the techniques and applications of laser microdissection microscopy are reviewed with suggestions of how the systems might be used to explore applied questions in parasite molecular biology and host-parasite interactions.

An in vitro larval motility assay to determine anthelmintic sensitivity for human hookworm and Strongyloides species

With the implementation of programs to control lymphatic filariasis and soil-transmitted helminths using broad spectrum anthelmintics, including albendazole and ivermectin, there is a need to develop an in vitro assay for detection of drug resistance. This report describes an in vitro assay for measuring the effects of ivermectin and benzimidazoles on the motility of larvae of the hookworm species Ancylostoma ceylanicum, A. caninum, and Necator americanus, and Strongyloides species including Strongyloides stercoralis, and S. ratti. A dose-response relationship was demonstrated with each of the parasite species, with distinct differences observed between the various species. In pilot field testing of the assay with N. americanus larvae recovered from human fecal samples, a dose-response relationship was observed with ivermectin. While the assay has demonstrated the ability to determine drug responsiveness, its usefulness in resistance detection will require correlation with the clinical outcome among individuals infected with parasite strains showing different drug sensitivities.

Avaliação in vivo da atividade anti-helmíntica do extrato de Senecio brasiliensis e de Acacia mearnsii em ovinos experimentalmente infectados.

As helmintoses gastrintestinais estão entre as principais causas de perdas econômicas e produtivas na cadeia de produção ovina, sendo o Haemonchus contortus um dos parasitos que mais impactam a produção de pequenos ruminantes, devido sua patogenicidade e alta prevalência nos rebanhos nacionais.