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181.
Marconni Victor da Costa Lana Noemi Rovaris Gardinali Raquel Aparecida Sales da Cruz Letícya Lerner Lopes Gustavo Sousa Silva João Garcia Caramori Júnior Anderson Castro Soares de Oliveira Marcos de Almeida Souza Edson Moleta Colodel Amauri Alcindo Alfieri Caroline Argenta Pescador 《Tropical animal health and production》2014,46(2):399-404
The objectives of this study were to (1) investigate the occurrence of hepatitis E virus (HEV) in pigs from large-scale and family-scale farms, (2) genetically characterize the strains isolated, and (3) study the pathogenesis of swine HEV infection via immunohistochemistry. A total of 50 pigs from 10 farms in Mato Grosso State, Brazil were divided according to type of production system into either large-scale farms (n?=?5) or family-scale farms (n?=?5). Samples of liver, gallbladder, small and large intestines, bile, and feces from the pigs were analyzed by nested PCR with primers targeting the ORF2 region of HEV and by immunohistochemistry. Of the eight HEV-positive samples from pigs of family-scale farms, phylogenetic analysis revealed that seven of the swine HEV isolates clustered with subtype 3b of genotype 3 and one isolate was categorized with subtype 3 f. The HEV antigen was detected mainly in the small intestine samples from family-scale farms, suggesting an early stage HEV infection. HEV was not detected in the samples of pigs from large-scale farms, reinforcing the need for additional studies to evaluate the risk of transmission of HEV to humans from pigs from family-scale farms in Mato Grosso State. 相似文献
182.
Manoel Eduardo da Silva Fabio Ribeiro Braga Luana Alcântara Borges Jair Mendes de Oliveira Walter dos Santos Lima Marcos Pezzi Guimarães Jackson Victor de Araújo 《Veterinary research communications》2014,38(2):101-106
Brazil has a herd of 212 million cattle and 171 million hectares of pastures that produce approximately 96 % of Brazilian beef. The Brazilian production system enables animal infection by endoparasites, which are considered one of the main obstacles for the development of this industry and are responsible for considerable economic losses. The control of parasitic diseases is performed via the administration of antiparasitic drugs, but they leave residues of the products in the treated animal, affect non-target organisms and select resistant strains of the parasites. The species D. flagrans and M. thaumasium are promising and sustainable alternatives for controlling gastrointestinal helminths of ruminants and other herbivores. In this study, we evaluated the efficacy of isolates of these species, formulated in a sodium alginate matrix and administered twice a week, to reduce the number of environmental infective larvae of gastrointestinal nematodes that affect prepubescent zebu females. The treated animals presented fewer eggs and a lower number of infective larvae per gram of faeces (p?<?0.05). The pastures occupied by treated animals showed a statistically significant reduction (p?<?0.05) of the number of L3 and, furthermore, the genera Cooperia sp., Haemonchus sp., and Oesophagostomum sp. were the most prevalent. The average weight of the animals did not differ statistically (p?>?0.05) among the treated and control groups. The use of sodium alginate pellets as vehicle for delivery of the fungus mycelia D. flagrans (isolate AC001) and M. thaumasium (isolate NF34A) proved effective in controlling trichostrongylids in prepubescent cows bred in the semi-arid region, with an effective reduction in the number of infective larvae in the pastures. 相似文献
183.
Vanessa Diniz Vieira Thais Ferreira Feitosa Vinícius Longo Ribeiro Vilela Sérgio Santos Azevedo João Leite de Almeida Neto Dayana Firmino de Morais Ana Raquel Carneiro Ribeiro Ana Célia Rodrigues Athayde 《Tropical animal health and production》2014,46(2):355-361
Gastrointestinal helminthiasis represents an obstacle to goat raising, causing severe damage to herds such as growth retardation, weight loss, and even death. In this study, we aimed to determine the prevalence and risk factors associated to goat gastrointestinal helminthiasis in the Sertão region of Paraíba State, Brazil. A total of 256 goats from 54 farms were systematically sampled. Blood and fecal samples were collected from each animal for egg per gram (EPG), larval culture, and packed cell volume (PCV) analyses. We found that 79.3 % of the goats investigated were parasitized with gastrointestinal helminths. Significant correlation (p?=?0.004) was observed between the EPG and PCV of the animals studied, and it was observed that the EPG increases as the PCV decreases. In the larval culture, the most prevalent helminth was Haemonchus sp. (83.2 %). Age and sex were significant variables (p?≤?0.20) for the development of gastrointestinal helminths: 86.8 % of animals over 36 months of age and 81.7 % of females were infected. The variable type of animal exploitation was also significant, with 90.3 % (p?≤?0.20) of the animals presenting double suitability (milk and meat). The Sertão region of Paraíba State presents high prevalence of gastrointestinal helminthiasis in goats, and age and type of animal exploitation are the most relevant risk factors to the development of these parasites. 相似文献
184.
Liliana R. Leite-Martins Maria I.M. Mahú Ana L. Costa Ângelo Mendes Elisabete Lopes Denisa M.V. Mendonça João J.R. Niza-Ribeiro Augusto J.F. de Matos Paulo Martins da Costa 《Preventive veterinary medicine》2014
Antimicrobial resistance (AMR) is a growing global public health problem, which is caused by the use of antimicrobials in both human and animal medical practice. The objectives of the present cross-sectional study were as follows: (1) to determine the prevalence of resistance in Escherichia coli isolated from the feces of pets from the Porto region of Portugal against 19 antimicrobial agents and (2) to assess the individual, clinical and environmental characteristics associated with each pet as risk markers for the AMR of the E. coli isolates. 相似文献
185.
Jessica Maria Leite dos Santos Jomar Patrício Monteiro Wesley Lyeverton Correia Ribeiro Iara Tersia Freitas Macedo Ana Lourdes Fernandes Camurça-Vasconcelos Luiz da Silva Vieira Claudia Maria Leal Bevilaqua 《Veterinary parasitology》2014,199(3-4):160-164
Haemonchus contortus is the most prevalent nematode in Brazil. The objective of this study was to select 6 populations of H. contortus of known or suspected benzimidazole resistance status and characterize these using quantitative real-time polymerase chain reaction (qPCR) for single nucleotide polymorphisms (SNPs) F200Y, F167Y and E198A in the β-tubulin isotype 1 gene. qPCR was performed using DNA from a pool of 10 adult male H. contortus from a single animal per farm. Faecal egg count reduction test (FECRT) and egg hatch test (EHT) were used to determine the resistance status. Samples were obtained from 6 farms located in 5 counties in the Ceará State: Tauá, Boa Viagem, Quixadá, Santa Quitéria and Solonópole. The inbred-susceptible-Edinburgh (ISE) isolate was used as reference for comparative purposes in the qPCR. Benzimidazole resistance was detected by FECRT on all farms with efficacy values ranging from 0 to 51%. EC50 values as determined by EHT were all above 1.49 μg/ml. High frequencies of the resistant SNPs F200Y and F167Y alleles were detected but no resistance was detected at SNP E198A. Our results suggest that the SNPs F167Y and F200Y are both important for benzimidazole resistance in the studied populations. 相似文献
186.
R. A. Silva Siqueira A. C. L. Luna T. A. Cavalcanti R. E. G. Rici M. A. Miglino R. R. Guerra 《Anatomia, histologia, embryologia》2014,43(1):1-5
The saffron finch (Sicalis flaveola brasiliensis) is a Passeriforme of the Brazilian wildlife. There are scarcely any morphological studies on it, although it is frequently trafficked for its birdsong abilities. Its peculiarities, such as territorialism and developed syrinx that provides outstanding song, draw attention towards its domestication. Thus, this study aimed to morphologically describe the tongue and digestive tube organs of this species to furnish subsidies for nutritional, clinical and conservation studies. Forty‐one birds from the Wild Animal Screening Center (CETAS)/Brazilian Institute of Environment (IBAMA)/city of Cabedelo, state of Paraíba (PB) were used. Samples were collected, identified and sent to standard light microscopy; samples of proventriculus and gizzard were sent to Scanning Electron Microscopy (SEM). The samples showed stratification similar to that of other domestic and wild birds, confirmed in the scanning electron microscopy; however, they differed in the absence of dermal papillae in the tongue, lack of ingluvial glands and lack of muscular mucosa and sub‐mucosa in the large intestine. 相似文献
187.
AM Batista WA Gomes CCD Carvalho PLJ Monteiro Jr FLM Silva FC Almeida PC Soares GF Carneiro MMP Guerra 《Reproduction in domestic animals》2014,49(3):476-480
The aim of this study was to evaluate the effect of leptin administration during superovulation on in vivo goat embryo production. Ten mature does were superovulated with 133 mg follicle‐stimulating hormone (FSH) i.m. in six descending doses at 12‐h intervals. The goats received 4.8 μg/kg human recombinant leptin s.c. (leptin group, n = 5) or phosphate‐buffered saline (PBS) (control group, n = 5) with the first and second FSH doses. The does were mated and subjected to embryo collection by transcervical technique 6 days later. The total number of cells per embryo and the number of cells with fragmented DNA were assessed in selected blastocysts by combining Hoechst 33342 and terminal dUTP nick‐end labelling (TUNEL) staining. Plasma concentrations of oestradiol (E2) and progesterone (P4) were determined by electrochemiluminescence from the day of FSH treatment, on the day of superovulatory oestrus and on the day before embryo collection. Compared with the control group, the does that received leptin had a higher number of transferable embryos (p < 0.005), fewer embryos classified as degenerated (p < 0.001) and fewer TUNEL‐positive cells/blastocyst (p < 0.001). The number of transferable embryos was positively correlated with E2 concentrations on day of oestrus (r = 0.562; p < 0.01) and P4 concentrations on the day of embryo collection (r = 0.912; p < 0.001). We concluded that in vivo leptin administration during FSH treatment improved embryo quality and affected ovarian steroidogenesis in superovulated goats. 相似文献
188.
KC Silva‐Santos LS Siloto GMG Santos F Morotti TN Marcantonio MM Seneda 《Reproduction in domestic animals》2014,49(1):48-51
The objective was to compare populations of antral and pre‐antral ovarian follicles in Bos indicus and Bos indicus‐taurus cows with high and low antral follicle counts. Nelore (Bos indicus, n = 20) and Nelore X Angus (1/2 Bos indicus‐taurus, n = 20) cows were subjected to follicular aspiration without regard to the stage of their oestrous cycle (day of aspiration = D0) to remove all follicles ≥3 mm and induce growth of a new follicular wave. Ovaries were examined by ultrasonography on D4, D19, D34, D49 and D64, and antral follicles ≥3 mm were counted. Thereafter, cows were assigned to one of two groups: high or low antral follicular count (AFC, ≥30 and ≤15 antral follicles, respectively). After D64, ovaries were collected after slaughter and processed for histological evaluation. There was high repeatability in the numbers of antral follicles for all groups (range 0.77–0.96). The mean (±SD) numbers of antral follicles were 35 ± 9 (Bos indicus) and 38 ± 6 (Bos indicus‐taurus) for the high AFC group and 10 ± 3 (Bos indicus) and 12 ± 2 (Bos indicus‐taurus) follicles for the low AFC. The mean number of preantral follicles in the ovaries of Bos indicus‐taurus cows with high AFC (116 226 ± 83 156 follicles) was greater (p < 0.05) than that of Bos indicus cows (63 032 ± 58 705 follicles) with high AFC. However, there was no significant correlation between numbers of antral and preantral follicles. 相似文献
189.
C. Eyng A. E. Murakami C. R. A. Duarte T. C. Santos 《Journal of animal physiology and animal nutrition》2014,98(2):393-401
The present study aimed to evaluate the effect of different levels of an ethanolic extract of propolis (EEP) on broiler performance, carcass characteristics, weight of gastrointestinal organs, intestinal morphometry and digestive enzyme activity. 1020 male broiler chicks were assigned in a completely randomised experimental design to six treatments (EEP supplement levels of 0, 1000, 2000, 3000, 4000 and 5000 ppm) and five replications, and 34 birds per experimental unit. The experimental diets were administered from 1 to 21 days of age, and the birds were subsequently provided a ration based on corn and soybean meal. EEP supplementation from 1 to 7 days negatively affected (p < 0.05) the weight gain and feed intake. The proventriculus weight at 7 days exhibited a quadratic response (p < 0.05), which predicted a lower weight at a dose of 2865 ppm of the EEP. For the duodenum at 21 days of age, the response pattern (p < 0.05) predicted that birds that were fed 2943 and 3047 ppm of the EEP would exhibit an improved crypt depth and villus‐to‐crypt ratio respectively. The villus height, crypt depth and villus‐to‐crypt ratio in the jejunum and the ileum were not affected (p > 0.05). With increased EEP doses, the duodenal sucrase activity linearly decreased at 7 days of age and linearly increased in the jejunum at 21 days of age (p < 0.05), while pancreatic enzyme activity was unaffected (p > 0.05). Although the carcass and cut yields did not improve, the percentage of abdominal fat decreased (p < 0.05). The supplementation of the broiler pre‐starter diet with 1000–5000 ppm of the EEP impaired performance at this stage, most likely due to the decreased sucrase activity. However, the EEP supplementation from 3000 ppm improved intestinal morphophysiology at 21 days of age and did not affect the performance or carcass yield at 42 days of age. 相似文献
190.
T Guimarães C Miranda M Pinto E Silva L Damásio AL Costa MJ Correia JC Duarte C Cosinha G Lopes G Thompson A Rocha 《Reproduction in domestic animals》2014,49(6):926-933
A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro‐organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non‐breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro‐organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro‐organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro‐organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro‐organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli. 相似文献