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1.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(4): 393-396, 2020 Jun 12.
Artigo em Chinês | MEDLINE | ID: mdl-32935515

RESUMO

OBJECTIVE: To investigate the prevalence and changing patterns of Schistosoma japonicum infections in goats in Dantu District of Zhenjiang City, so as to provide the scientific data for the management of in livestock. METHODS: The S. japonicum infections were detected using a miracidial hatching test (one test for one stool specimen) in goats grazed in settings with snail habitats in Dantu District of Zhenjiang City at spring and autumn of each year from 2004 to 2019, and the prevalence and intensity of S. japonicum infections were estimated. RESULTS: A total of 21 836 goat stool samples were detected from 2004 to 2019, and 86 were positive for S. japonicum (0.39% prevalence). The highest prevalence of S. japonicum infections in goats was seen in 2004 (1.25%) and no infections were detected in goats since 2013. S. japonicum-infected goats were identified in marshland-type endemic areas and plain regions with waterway networks, and there was a significant difference in the prevalence of S. japonicum infections in goats between these two types of endemic areas (0.50% vs. 0.15%; χ2 = 11.566, P < 0.05). The prevalence of S. japonicum infections was significantly greater in goats at ages of more than 10 months (0.51%) and over 10 months (0.44%) than in other goats (χ2 = 13.088, P < 0.05), and higher prevalence was found in autumn than in spring (0.54% vs. 0.27%; χ2 = 9.597, P < 0.05). In addition, there were 76.74% of S. japonicum-infected goats with intensity of"+++"and"++++". CONCLUSIONS: Although the high prevalence of S. japonicum infections has been effectively controlled in goats in Dantu District, goat remains to be an important source of S. japonicum infections that should be given a high priority for control to consolidate the schistosomiasis control achievements.


Assuntos
Doenças das Cabras , Schistosoma japonicum , Esquistossomose Japônica , Animais , China/epidemiologia , Cidades , Doenças das Cabras/epidemiologia , Doenças das Cabras/parasitologia , Cabras , Prevalência , Esquistossomose Japônica/epidemiologia , Esquistossomose Japônica/veterinária , Caramujos
2.
J S Afr Vet Assoc ; 91(0): e1-e11, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32787418

RESUMO

This study investigated the occurrence and phylogenetic relationship of protozoan parasites and Ehrlichia infecting domestic animals from three municipalities in uMkhanyakude district of KwaZulu-Natal province, South Africa. A total of 208 blood samples collected from clinically healthy cattle, sheep, goats and dogs from uMkhanyakude district were examined by polymerase chain reaction (PCR) assays, using either genus or species-specific primers to determine the occurrence and phylogenetic relationship of various protozoan parasites and Ehrlichia of veterinary importance. A total of 5/109 (4.6%) cattle were PCR-positive for the presence of Toxoplasma gondii, 33/109 (30.3%) for Babesia bovis, 24/109 (22.02%) for Babesia bigemina and 20/109 (18.3%) for Trypanosoma sp., while 3/10 (30%) of sheep were PCR-positive for Theileria ovis and none of the goats were positive for any of the detected pathogens. The co-infection of 4/109 (3.7%) B. bovis and B. bigemina was detected in cattle. Only Ehrlichia canis was detected in dogs with infection rate of 20/48 (41.7%). Sequences of PCR-positive isolates (B. bovis, B. bigemina, E. canis, T. ovis and T. gondii) showed that they were closely related to their relevant species from various countries. These findings have expanded our knowledge about the prevalence and phylogenetic similarity between protozoan parasites and Ehrlichia isolates of South African origin. To date, this is the first study in South Africa to detect T. gondii infections from cattle blood using PCR.


Assuntos
Babesiose/parasitologia , Coinfecção/veterinária , Ehrlichiose/veterinária , Theileriose/parasitologia , Toxoplasmose Animal/parasitologia , Tripanossomíase/veterinária , Animais , Babesia/classificação , Babesia/isolamento & purificação , Babesiose/microbiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Coinfecção/microbiologia , Coinfecção/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Ehrlichia canis/isolamento & purificação , Ehrlichiose/microbiologia , Ehrlichiose/parasitologia , Doenças das Cabras/epidemiologia , Doenças das Cabras/microbiologia , Doenças das Cabras/parasitologia , Cabras , Prevalência , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/parasitologia , África do Sul/epidemiologia , Theileria/isolamento & purificação , Theileriose/microbiologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/microbiologia , Trypanosoma/classificação , Trypanosoma/isolamento & purificação , Tripanossomíase/microbiologia , Tripanossomíase/parasitologia
3.
Parasitol Res ; 119(8): 2539-2548, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32562068

RESUMO

Strongylida are gastrointestinal nematodes (GIN) of greatest importance in small ruminants throughout the world. Differences in resistance and resilience to GIN among goat breeds were reported. This study aims to investigate the mechanism underlying the breed-associated differences using a cosmopolitan (Alpine, AB) and an autochthonous (Nera di Verzasca, NV) goat breed. At first, fifteen goats from the same herd (NV = 7, AB = 8) at day 0 were infected with infective larvae (L3) of mixed GIN. From the 15th day post-infection (DPI), individual parasite egg excretion (faecal egg counts, FEC) was performed on all goats, once per week, until the 63rd DPI. Afterwards, in goats under field conditions (30 AB and 30 NV reared on the same farm), individual faecal and blood samples were collected; FEC-specific antibody and PCV levels were explored. In goats with experimental GIN infection, mean eggs per gram of faeces (EPG) values were consistently lower in NV goats. In goats with natural GIN infection, EPG and prevalence values showed high variability in both breeds; among individual variables, breed had a significant influence on EPG. Further, PCV and anti-T. circumcincta IgA levels were influenced by the breed. Lower PCV values were also associated with higher strongyle EPG in AB goats, and anti-T. circumcincta IgA levels were influenced by both strongyle EPG and breed, with IgA levels being higher in AB vs. NV goats and positively associated with EPG. Neither EPG nor breed had any influence on IgE levels. Both studies on experimental and natural infection confirmed that goats of NV are more resistant to infection with gastrointestinal nematodes.


Assuntos
Gastroenteropatias/veterinária , Doenças das Cabras/parasitologia , Infecções por Strongylida/veterinária , Animais , Formação de Anticorpos , Fezes/parasitologia , Feminino , Gastroenteropatias/sangue , Gastroenteropatias/parasitologia , Doenças das Cabras/sangue , Cabras/classificação , Cabras/imunologia , Cabras/parasitologia , Masculino , Contagem de Ovos de Parasitas/veterinária , Especificidade da Espécie , Infecções por Strongylida/sangue , Infecções por Strongylida/parasitologia
4.
Parasitol Res ; 119(9): 2813-2819, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32583163

RESUMO

Cryptosporidium is an opportunistic protozoan parasite that can inhabit in the gastrointestinal tract of various hosts. Cryptosporidium infection in black-boned goats and black-boned sheep may pose a threat to the survival and productivity, causing considerable economic losses to the livestock industry. However, it is yet to know whether black-boned goats and black-boned sheep in China are infected with Cryptosporidium. Thus, the objective of the present study was to investigate the prevalence and associated risk factors of Cryptosporidium infection in black-boned goats and black-boned sheep in Yunnan province, China. A total of 590 fecal samples were obtained from black-boned goats and black-boned sheep from five counties in Yunnan province, and the prevalence and species distribution of Cryptosporidium were determined by amplification of the 18S rDNA fragment using the nested PCR. The overall Cryptosporidium prevalence was 13.2% (78/590), with 18.0% (55/305) in black-boned goats and 8.1% (23/285) in black-boned sheep. The age and sampling site were identified as main factors that result in significant differences in Cryptosporidium prevalence. Three species, namely C. muris, C. xiaoi, and C. ubiquitum, were identified in black-boned goats and black-boned sheep in the present study, with C. muris (46/78) as the predominant species. This is the first report of Cryptosporidium infection in black-boned goats and black-boned sheep in China, and the findings will facilitate better understanding, prevention, and control of Cryptosporidium infection in black-boned goats and black-boned sheep in China.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium/isolamento & purificação , Doenças das Cabras/parasitologia , Reação em Cadeia da Polimerase/veterinária , Doenças dos Ovinos/parasitologia , Animais , China/epidemiologia , Cryptosporidium/classificação , Cryptosporidium/genética , Fezes/parasitologia , Trato Gastrointestinal/parasitologia , Cabras/parasitologia , Prevalência , RNA Ribossômico 18S/genética , Fatores de Risco , Ovinos/parasitologia
5.
Parasitol Res ; 119(7): 2067-2073, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32468188

RESUMO

Fleas are ectoparasites of mammals and birds. In livestock such as sheep and goat, flea bites cause many clinical signs. Several types of insecticides including pyrethroids are used to struggle against fleas. The widespread use of these insecticides causes an increase in the number of resistant individuals in flea populations. T929V and L1014F mutations corresponding to pyrethroid resistance have been found in the para gene of cat fleas. We aimed to investigate T929V and L1014F mutations in flea samples (n:162) collected from goats in seven different farms where cypermethrin, a synthetic pyrethroid, had been used intensively. To achieve this aim, collected flea samples were morphologically identified under a stereo microscope and DNA isolation was conducted by HotSHOT method. Later, a bi-PASA targeting the para gene was applied to identify both mutations in corresponding samples. According to the results obtained, all fleas were Ctenocephalides felis. Frequencies of T929V and L1014F mutations in fleas were 92.6% (150/162) and 95.7% (155/162), respectively. In conclusion, the frequency of mutations related to pyrethroid resistance was very high in the fleas collected from all the farms and it was thought that the high frequency of these mutations can be attributed to intensive use of pyrethroids.


Assuntos
Ctenocephalides/genética , Infestações por Pulgas/veterinária , Genes de Insetos/genética , Doenças das Cabras/parasitologia , Resistência a Inseticidas/genética , Piretrinas , Animais , Infestações por Pulgas/parasitologia , Cabras , Inseticidas , Mutação
6.
Trop Anim Health Prod ; 52(5): 2213-2219, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388661

RESUMO

Endoparasitic nematode infection could have negative impacts on performances of sheep and goats. However, supplementary protein and minerals can also affect nematodes. This paper reviews present information on the importance of protein and minerals supplementation as means to control nematode infection in small ruminants. Protein supplementation seems to improve host resilience by diverting metabolizable protein (MP) towards dealing with detrimental effects of the infection and thus improve production and reproductive performances of animal. A large body of evidence shows that supplementation of copper, iron, and zinc can also enhance host resistance against nematode infection as shown by decreased fecal egg count (FEC) and worm burdens. As such, protein and mineral supplementations can play a major role in sustainable control of parasitic nematode infection and thus reduce reliance on chemotherapic drugs.


Assuntos
Proteínas na Dieta/metabolismo , Doenças das Cabras/tratamento farmacológico , Minerais/metabolismo , Infecções por Nematoides/veterinária , Substâncias Protetoras/farmacologia , Doenças dos Ovinos/tratamento farmacológico , Ração Animal/análise , Animais , Dieta/veterinária , Proteínas na Dieta/administração & dosagem , Suplementos Nutricionais/análise , Doenças das Cabras/parasitologia , Cabras , Minerais/administração & dosagem , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
7.
J Parasitol ; 106(2): 316-322, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32330281

RESUMO

Fascioliasis is a zoonotic infection of humans and, more commonly, ruminants. It is caused by 2 liver fluke species, Fasciola hepatica and Fasciola gigantica, which differ in size. The traditional morphological methods used to distinguish the 2 species can be unreliable, particularly in the presence of hybrids between the 2 species. The development of advanced molecular methods has allowed for more definitive identification of Fasciola species, including their hybrids. Hybrids are of concern, as it is thought that they could acquire advantageous traits such as increased pathogenicity and host range. In 2013, we collected flukes from Fasciola-positive cattle, sheep, and goats slaughtered in 4 Chadian abattoirs. DNA from 27 flukes was extracted, amplified, and analyzed to identify species using the ITS1+2 locus. Twenty-six of the 27 flukes were identified as F. gigantica, while the remaining fluke showed heterozygosity at all variable sites that distinguish F. hepatica and F. gigantica. Cloning and sequencing of both alleles confirmed the presence of 1 F. hepatica and 1 F. gigantica allele. To our knowledge, this is the first unambiguous, molecular demonstration of the presence of such a hybrid in a bovine in sub-Saharan Africa.


Assuntos
Doenças dos Bovinos/parasitologia , Quimera/genética , Fasciola hepatica/genética , Fasciolíase/veterinária , Matadouros , Animais , Bovinos , Chade , Quimera/classificação , Sequência Consenso , Fasciola/classificação , Fasciola/genética , Fasciola/isolamento & purificação , Fasciola hepatica/classificação , Fasciola hepatica/isolamento & purificação , Fasciolíase/parasitologia , Feminino , Inspeção de Alimentos , Doenças das Cabras/parasitologia , Cabras , Polimorfismo de Nucleotídeo Único/genética , Ovinos , Doenças dos Ovinos/parasitologia
8.
J Parasitol ; 106(3): 360-368, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32227225

RESUMO

Anaplasmosis is caused by a Gram-negative obligate intracellular bacterium of the genus Anaplasma with the pathogen having a zoonotic impact. The study aimed to estimate the prevalence of anaplasmosis in Pakistan, to unravel the association of potential risk factors, and to investigate the effect on hematological parameters in affected small ruminants. A total of 150 (n = 75 sheep; n = 75 goats) blood samples were initially screened microscopically and then subjected to PCR targeting the amplification of the 16S rRNA gene fragment of Anaplasma. The PCR-based positive samples were then processed for sequencing. Statistical analysis regarding risk factors was performed using R software. The study revealed an overall 29.33% (44/150) prevalence of anaplasmosis in small ruminants. Sheep had higher (P > 0.05) prevalence (32%) as compared to goats (25.30%). The final statistical model resulting from backward elimination showed only tick infestation as a significant predictor of infection status. The phylogenetic analysis of 16S rRNA gene of Anaplasma spp. revealed 9 study isolates clustered together and showed a close resemblance (99%) with Anaplasma ovis isolate (DQ837600) from Hungary. One of the isolates showed (99%) similarity with the isolate of Anaplasma marginale (MH155594) from Iraq. Furthermore, the hematological parameters pack cell volume, red blood cells, hemoglobin, white blood cells, granulocytes, monocytes, lymphocytes, and platelet count were decreased in Anaplasma-positive animals. This is the first study at the molecular level to characterize Anaplasma spp. in small ruminants of Pakistan, and it will be useful in developing control strategies for anaplasmosis.


Assuntos
Anaplasma/genética , Anaplasmose/parasitologia , Doenças das Cabras/parasitologia , Doenças dos Ovinos/parasitologia , Zoonoses/parasitologia , Anaplasma/classificação , Anaplasma/fisiologia , Anaplasmose/sangue , Anaplasmose/epidemiologia , Animais , Sequência de Bases , DNA Bacteriano/sangue , DNA Bacteriano/isolamento & purificação , Feminino , Doenças das Cabras/sangue , Doenças das Cabras/epidemiologia , Cabras , Incidência , Masculino , Análise Multivariada , Paquistão/epidemiologia , Filogenia , Prevalência , RNA Ribossômico 16S/genética , Análise de Regressão , Fatores de Risco , Alinhamento de Sequência , Fatores Sexuais , Ovinos , Doenças dos Ovinos/sangue , Doenças dos Ovinos/epidemiologia , Zoonoses/sangue , Zoonoses/epidemiologia
9.
Ann Parasitol ; 66(1): 3-12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32198990

RESUMO

Parasites are transferred between domestic and wild animals, when host animals come in contact with each other, particularly while grazing the same pastures, or when using same water bodies for drinking. Chances of parasite transmission and adaptation are high when hosts are genetically related. Afghan urial (Ovis vignei blanfordi), Suleiman markhor (Capra falconeri jerdoni) and Chiltan wild goat (C. aegagrus chialtanensis) are wild kin of domestic sheep and goats, sharing numerous parasitic diseases with each other. The present study was conducted in 2014­2015, to determine parasitic infections of Suleiman markhor and Afghan urial of Torghar Game Reserve, and the endemic wild goat of Chiltan National Park. For comparison, parasites of domestic small ruminants of these areas were also studied. A total of 11 species of helminth and 20 species of protozoa were recorded. Highly prevalent helminth among wild ruminants were Trichuris spp., Nematodirus spp., Protostrongylus rufescens and Moniezia benedeni, while highly prevalent Eimeria were E. arloingi and E. ninakohlyakimovae in caprines and E. ovinoidalis in urial. Chiltan wild goats were also found infected with Entamoeba spp. A short tabulated review of the helminth and protozoan parasites of wild sheep and goats of Pakistan, India, Iran and Turkey has been presented.


Assuntos
Doenças das Cabras , Cabras/parasitologia , Helmintíase Animal , Parasitos , Infecções Protozoárias em Animais , Animais , Eucariotos/classificação , Eucariotos/isolamento & purificação , Doenças das Cabras/parasitologia , Helmintíase Animal/parasitologia , Helmintos/classificação , Helmintos/isolamento & purificação , Índia , Irã (Geográfico) , Paquistão , Parasitos/classificação , Parasitos/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia
10.
Exp Parasitol ; 212: 107872, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32165145

RESUMO

Theileriosis is a widespread and economically important disease of small ruminants in Pakistan. Ruminants are the intermediate hosts in the lifecycle of Theileria spp., with ticks of the family Ixodidae being the definitive hosts. To better understand the distribution and prevalence of theileriosis in Pakistan, a molecular survey was performed in small ruminants from the Lower Dir district of the Khyber Pakhtunkhwa province. A total of 200 healthy sheep and goats were screened from Maidan, Samar Bagh and Munda districts of district Dir Lower, Pakistan during December (2017) to April (2018). DNA samples were screened through nested PCR using universal primers. The amplified 492-498 bp amplicon was subjected to RLB analysis which was based on the hypervariable of the 18S rRNA gene to test for the presence of genotypes of Theileria in blood samples. A phylogeny was constructed to determine the species of Theileria genotypes. Nested PCR results indicated 53.5% prevalence of one or more Theileria genotypes in the blood of the host animal. From RLB assay, 27 animals (13.5%) showed infection with only a single species of Theileria while 80 animals (40%) showed coinfection by multiple Theileria spp. Based on the 18S rRNA phylogeny, the unknown genotype is of the species Theileria luwenshuni and is closely related to Chinese isolates. The present finding is the first report on molecular diagnosis of Theileria luwenshuni in small ruminants in Pakistan.


Assuntos
Doenças das Cabras/parasitologia , Doenças dos Ovinos/parasitologia , Theileria/isolamento & purificação , Theileriose/parasitologia , Distribuição por Idade , Análise de Variância , Animais , Coinfecção/epidemiologia , Coinfecção/parasitologia , DNA de Protozoário/química , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Ribossômico/isolamento & purificação , Feminino , Genótipo , Doenças das Cabras/epidemiologia , Cabras , Hibridização Genética , Funções Verossimilhança , Modelos Lineares , Masculino , Análise Multivariada , Sondas de Oligonucleotídeos , Paquistão/epidemiologia , Filogenia , Reação em Cadeia da Polimerase , Prevalência , RNA Ribossômico 18S/genética , Fatores de Risco , Análise de Sequência de DNA , Distribuição por Sexo , Ovinos , Doenças dos Ovinos/epidemiologia , Theileria/classificação , Theileria/genética , Theileriose/epidemiologia
11.
Parasite Immunol ; 42(6): e12707, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118305

RESUMO

AIMS: Most breeds of goat are more susceptible to nematode infection than sheep, and this appears to be a consequence of less effective immune responses. Several papers have considered the effectiveness of eosinophils and immunoglobulin A (IgA) in goats but differences in the induction of responses have not been studied in the same detail. The aim of this study was to look at the induction of eosinophil and IgA responses in Boer goats reared indoors under intensive conditions. METHODS AND RESULTS: The goats were experimentally infected with a low dose of 2400 Haemonchus contortus, Trichostrongylus spp. and Oesophagostomum spp. at a 6:1:1 ratio. Faecal egg counts (FEC), packed cell volume (PCV), IgA activity against third-stage larvae and peripheral eosinophilia were measured twice a week for eight weeks. The infection generated an IgA response but did not significantly increase peripheral eosinophilia in the 25 infected kids compared with the 4 control animals. FEC was not associated with IgA activity or eosinophilia. CONCLUSION: A detailed analysis of IgA and eosinophil responses to deliberate nematode infection in Boer goats showed that there was an increase in nematode-specific IgA activity but no detectable eosinophil response. In addition, there was no association between increased IgA activity or eosinophilia with egg counts and worm burdens. These suggest that IgA and eosinophils do not act to control nematode infection in goats.


Assuntos
Eosinofilia/imunologia , Doenças das Cabras/parasitologia , Cabras/imunologia , Hemoncose/veterinária , Haemonchus/imunologia , Imunoglobulina A/imunologia , Animais , Anticorpos Antiprotozoários/imunologia , Eosinofilia/parasitologia , Eosinófilos/imunologia , Fezes/parasitologia , Feminino , Doenças das Cabras/imunologia , Cabras/parasitologia , Hemoncose/imunologia , Hemoncose/parasitologia , Hematócrito/veterinária , Contagem de Leucócitos , Masculino , Oesophagostomum/imunologia , Contagem de Ovos de Parasitas/veterinária , Trichostrongylus/imunologia
12.
Vet Microbiol ; 242: 108607, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32122611

RESUMO

Parasitic infections are associated with profound changes in the structure and function of the gut microbiome in various host-parasite systems. Here we examined the microbial composition and function in the abomasum, proximal colon and feces of Haemonchus contortus-infected goats after a partial anthelmintic drug clearance. A single-dose treatment of H. contortus-infected goats with Cydectin (moxidectin) resulted in an 83.9 % and 61.8 % reduction in fecal egg counts (EPG) and worm burden, respectively (P < 0.01), and restored abomasal pH to a normal baseline level. The treatment significantly increased the abundance of Proteobacteria, particularly that of Campylobacter, in the proximal colon. It also significantly affected several basic pathways, including bacterial secretion, butyrate metabolism, and LPS biosynthesis, and seemingly reduced the cellulolytic capacity in the colon. Several network modules displayed a strong correlation with EPG and worm burden. The Mantel test indicated a strong correlation between treatment related network topologies of the operational taxonomic units (OTU) belonging to Actinobacteria and Rikenellaceae and EPG and worm burden levels, respectively. Furthermore, microbial signatures that may better predict anthelmintic efficacy were identified. A signature or balance represented by the log ratio of the abundance of Verrucomicrobiaceae and Camplyobacteraceae had a strong correlation with EPG (r = 0.80). These novel insights into the interactions between H. contortus and gut microbiome in the caprine host and the consequence of a partial anthelmintic clearance on animal health and well-being may facilitate the design of more effective next-generation anthelmintics.


Assuntos
Anti-Helmínticos/uso terapêutico , Bactérias/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Doenças das Cabras/tratamento farmacológico , Hemoncose/veterinária , Macrolídeos/uso terapêutico , Animais , Bactérias/classificação , Colo/efeitos dos fármacos , Colo/microbiologia , Fezes/parasitologia , Doenças das Cabras/parasitologia , Cabras/parasitologia , Hemoncose/tratamento farmacológico , Haemonchus , Masculino , Redes e Vias Metabólicas/efeitos dos fármacos , Contagem de Ovos de Parasitas/veterinária , Carga Parasitária/veterinária , RNA Ribossômico 16S/genética , Resultado do Tratamento
13.
Vet Parasitol ; 280: 109087, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32220696

RESUMO

Mixed grazing of breeding goats and cattle (goats to cattle ratio: about 50 %, based on metabolic weight) was monitored for 2 years on a rotational pasture with the two species grazing together, then for 5 years with cattle grazing immediately after goats. For both modalities, the level of goat parasite infection was not significantly different from that of the control groups. Nevertheless, the association allowed a slight improvement in kid growth and goat productivity, probably in relation to a better food quality. The response of adult goats to mixed grazing is therefore very different from that previously obtained with kids post-weaning. The question of the relationship between heterogeneity of pastures, knowledge of their environment, grazing behaviour of adult goats and risk of infection with gastrointestinal nematodes requires further investigation.


Assuntos
Criação de Animais Domésticos , Comportamento Alimentar , Doenças das Cabras/epidemiologia , Nematoides/fisiologia , Infecções por Nematoides/veterinária , Animais , Bovinos/fisiologia , Doenças das Cabras/parasitologia , Cabras/fisiologia , Pradaria , Guadalupe/epidemiologia , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia
14.
Parasit Vectors ; 13(1): 114, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32122383

RESUMO

BACKGROUND: Benzimidazole (BZ) resistance in gastrointestinal nematodes is a worldwide problem for livestock production, particularly in small ruminants. Assignment of the emergence of resistance using sensitive and reliable methods is required to adopt the correct strategies for control. In Sudan, BZ resistant Haemonchus contortus populations were recently reported in goats in South Darfur. This study aimed to provide additional data regarding albendazole efficacy and to describe the prevailing molecular BZ resistance mechanisms. METHODS: Faecal egg count reduction and egg hatch tests (EHT) were used to evaluate albendazole efficacy in three different areas of South Darfur using naturally (Rehed Al-Birdi and Tulus) and experimentally infected (Tulus and Um Dafuq) goats. Using samples from Central, East and South Darfur, pyro- and Sanger sequencing were used to detect the polymorphisms F167Y, E198A and F200Y in H. contortus isotype 1 ß-tubulin in DNA extracted from pooled third-stage larval (L3) samples (n = 36) on days 0 and 10 during trials, and from pooled adult male H. contortus (treated goats, n = 14; abattoirs, n = 83) including samples from populations previously found to be resistant in South Darfur. RESULTS: Albendazole efficacies at 5, 7.5 and 10 mg/kg doses were 73.5-90.2% on day 14 in natural and experimental infections while 12.5 mg/kg showed > 96.6% efficacy. EC50 in the EHT were 0.8 and 0.11 µg/ml thiabendazole in natural and experimental infection trials, respectively. PCRs detected Haemonchus, Trichostrongylus and Cooperia in L3 samples from albendazole-treated goats. Haemonchus contortus allele frequencies in codons 167 and 200 using pyrosequencing assays were ≤ 7.4% while codon 198 assays failed. Sanger sequencing revealed five novel polymorphisms at codon 198. Noteworthy, an E198L substitution was present in 82% of the samples (L3 and adults) including all post-treatment samples. Moreover, E198V, E198K and potentially E198I, and E198Stop were identified in a few samples. CONCLUSIONS: To our knowledge, this is the first report of E198L in BZ resistant H. contortus and the second where this is the predominant genotype associated with resistance in any strongyle species. Since this variant cannot be quantified using pyrosequencing, the results highlight important limitations in the general applicability of pyrosequencing to quantify BZ resistance genotypes.


Assuntos
Benzimidazóis/farmacologia , Códon , Resistência a Medicamentos/genética , Doenças das Cabras/parasitologia , Haemonchus/genética , Polimorfismo de Nucleotídeo Único , Tubulina (Proteína)/genética , Albendazol/farmacologia , Animais , DNA de Helmintos/isolamento & purificação , Fezes/parasitologia , Feminino , Frequência do Gene , Genótipo , Doenças das Cabras/tratamento farmacológico , Cabras , Haemonchus/efeitos dos fármacos , Masculino , Análise de Sequência de DNA , Sudão , Trichostrongyloidea/genética , Trichostrongylus/genética
15.
Vet Clin North Am Food Anim Pract ; 36(1): 159-171, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029181

RESUMO

This article summarizes the state of the art in vaccine research against parasitic helminths in sheep and cattle. Optimization of antigen production (eg, recombinant expression) and antigen delivery, followed by extensive field testing, is still required for further development of vaccines. Helminth vaccines should sufficiently reduce parasite transmission to protect vaccinated animals against parasite-induced disorders and production loss. Vaccine efficacy requirements depend on the parasite's epidemiology and farm management, both of which vary in different geographic regions and are influenced by climate. Vaccination is likely to be part of integrated worm control, together with other worm control measures.


Assuntos
Doenças dos Bovinos/prevenção & controle , Doenças das Cabras/prevenção & controle , Helmintos/imunologia , Doenças dos Ovinos/prevenção & controle , Vacinas/administração & dosagem , Animais , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/parasitologia , Doenças das Cabras/imunologia , Doenças das Cabras/parasitologia , Cabras , Ovinos , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/parasitologia , Vacinação/veterinária , Vacinas/imunologia
16.
Vet Clin North Am Food Anim Pract ; 36(1): 17-30, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029182

RESUMO

Control of gastrointestinal nematodes has been based on anthelmintics. However, this strategy is unsustainable owing to anthelmintic resistance. Parasitic nematodes have biologic and genetic features that favor the development of drug resistance, making the emergence of resistant nematodes inevitable. The rate of resistance development is affected controllable factors. There is a need to change the paradigm of how gastrointestinal nematodes are controlled to decrease the rate at which resistance develops. This article reviews the biology and prevalence of anthelmintic resistance, and provides recommendations for diagnosing resistance and for strategies that should be implemented to reduce the development of resistance.


Assuntos
Anti-Helmínticos/farmacologia , Doenças dos Bovinos/tratamento farmacológico , Doenças das Cabras/tratamento farmacológico , Gado/parasitologia , Infecções por Nematoides/veterinária , Doenças dos Ovinos/tratamento farmacológico , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Resistência a Medicamentos , Doenças das Cabras/epidemiologia , Doenças das Cabras/parasitologia , Cabras , Nematoides/isolamento & purificação , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/epidemiologia , Prevalência , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia
17.
Vet Clin North Am Food Anim Pract ; 36(1): 187-203, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029184

RESUMO

Ruminant coccidiosis, caused by Eimeria species, is a significant and widespread enteric disease in young livestock worldwide. High morbidities and significant mortalities may be observed. For disease diagnosis, fecal samples from clinically ill animals should be analyzed for both, identity (ie, pathogenicity) of Eimeria species and excreted oocyst amount. To prevent coccidiosis-related economic losses, management measures to reduce infection pressure and improve general animal health are crucial. Anticoccidial drugs are widely used to control clinical and subclinical disease. Treatment is most efficient when applied prophylactically or metaphylactically. To avoid development of parasite drug resistance, drugs should be used sustainably.


Assuntos
Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Doenças das Cabras/parasitologia , Doenças dos Ovinos/parasitologia , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Coccidiose/prevenção & controle , Fezes/parasitologia , Doenças das Cabras/prevenção & controle , Cabras , Gado/parasitologia , Ruminantes/parasitologia , Ovinos , Doenças dos Ovinos/prevenção & controle
18.
Vet Clin North Am Food Anim Pract ; 36(1): 205-222, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029185

RESUMO

Neospora caninum, Toxoplasma gondii, and Sarcocystis spp. are related Apicomplexan parasites that have 2 hosts in their life cycles. The definitive hosts excrete unsporulated (Neospora caninum, T gondii) or sporulated (Sarcocystis spp.) oocysts in their feces after ingesting tissue cysts from the tissues of ruminant intermediate hosts. These coccidians can cause abortion and neonatal mortality in ruminants. T gondii and Sarcocystis hominis (from cattle) are zoonotic. This article reviews information on the etiology, life cycle, diagnosis, control and prevention of these parasites and the diseases they cause in ruminants.


Assuntos
Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Doenças das Cabras/parasitologia , Sarcocistose/veterinária , Doenças dos Ovinos/parasitologia , Animais , Bovinos , Cabras , Neospora/isolamento & purificação , Ruminantes/parasitologia , Ovinos , Toxoplasma/isolamento & purificação , Toxoplasmose Animal
19.
Vet Clin North Am Food Anim Pract ; 36(1): 73-87, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029190

RESUMO

Strongylid gastrointestinal nematodes are an important cause of disease and economic loss in small ruminants. These parasites are important in most of the United States, with the bloodsucking parasite Haemonchus contortus being the predominant species of concern. Sheep and goats are infected while grazing, and the biology of infective larvae on pastures is important in the design of parasite management programs. Widespread resistance to anthelmintics requires strategies designed to preserve remaining drug activity; these include combination treatments with multiple classes of anthelmintics and targeted treatments.


Assuntos
Doenças das Cabras/epidemiologia , Doenças das Cabras/prevenção & controle , Infecções por Nematoides/veterinária , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/prevenção & controle , Animais , Anti-Helmínticos/administração & dosagem , Trato Gastrointestinal/parasitologia , Doenças das Cabras/tratamento farmacológico , Doenças das Cabras/parasitologia , Cabras , Nematoides/isolamento & purificação , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/prevenção & controle , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia
20.
Vet Clin North Am Food Anim Pract ; 36(1): 89-107, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029191

RESUMO

It is increasingly difficult to manage and control gastrointestinal nematode parasites in pasture-based ruminant livestock operations because of the high prevalence of anthelmintic resistance. Anthelmintics should be combined with alternative forms of control. Sustainable tools include copper oxide wire particles and condensed tannin-rich plants, which target primarily Haemonchus contortus in small ruminants. Nematophagous fungi reduce larvae on pasture and target nematode larvae in feces of most livestock species. In addition, and perhaps most importantly, genetic selection focuses on parasite resistance. Producers should use as many tools as possible to minimize the need for pharmaceutical interventions and optimize animal production.


Assuntos
Hemoncose/veterinária , Animais , Anti-Helmínticos/administração & dosagem , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Cobre/administração & dosagem , Doenças das Cabras/tratamento farmacológico , Doenças das Cabras/parasitologia , Cabras , Hemoncose/tratamento farmacológico , Haemonchus/isolamento & purificação , Gado/parasitologia , Proantocianidinas/administração & dosagem , Ruminantes/parasitologia , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia
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