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11.
The use of native and adapted forages is an alternative for sustainable production systems in northeast Brazil. The goal of this study was to evaluate the substitution of Tifton 85 by maniçoba hay on the performance and carcass traits of Morada Nova hair sheep. The 16 lambs that were used in this study initially weighed 19.36?±?1.48 kg, were housed in individual pens, and were slaughtered at 58 days of confinement. The dry matter intake (839.84 g/day and 3.81 % WB) was higher (P?<?0.05) in sheep fed maniçoba hay. The feed conversion was 7.39 for sheep fed maniçoba hay. The empty body weight (21.61 kg) and cold carcass weight (11.40 kg) did not differ (P?>?0.05) between sheep fed different hay types. The replacement of Tifton 85 by maniçoba hay did not influence the loin eye area (cm2) or carcass compactness index (kg/cm). The replacement of Tifton 85 by maniçoba hay in Morada Nova sheep diet did not affect the weight gain or carcass characteristics. The maniçoba hay can be considered a forage resource for feeding sheep in Brazilian semiarid tropics.  相似文献   
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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   
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Epitheliocystis in the leafy sea-dragon   总被引:2,自引:0,他引:2  
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Abstract— Most marine fish larviculture is dependent on the culture and nutritional manipulation of live prey, of which the rotifers Brachionus sp. are one of the most commonly used. The particular reproductive characteristics of gilthead seabream Spus aurata L. lead to an egg overproduction in commercial hatcheries, where the excess is normally wasted. This study was developed with the objective of testing seabream eggs as an enrichment product for Brachionus sp., using as control the commercial product Algamac 2000×. In view of the need to preserve and store the eggs produced in excess, freezedrying was examined as a possible technical solution for this purpose. The fatty acid profiles of the tested enrichment products (fresh seabream eggs, freeze-dried eggs and Algamac 2000×), as well as of the enriched rotifers at 0 h and after 3,6,12, 15, 18 and 24 h of enrichment, were analyzed. Freeze-dried eggs were stored for 14 and 58 wk prior to analysis, in order to examine a potential deterioration of the fatty acid nutritional quality. A potential use of seabream eggs as an enrichment product for Brachionus sp. was demonstrated. Rotifers enriched with eggs, fresh and freeze-dried, presented relatively high levels of polyunsaturated fatty acids (PUFA), highly unsaturated fatty acids (HUFA; × C20 and 2 double bonds), and fatty acid methyl esters (FAME), a docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) ratio of about 2 and a fairly high (n-3)/(n-6) ratio, especially during the first 3-6 h of enrichment. When freeze-dried eggs were stored in a dry atmosphere during 14 and 58 wk, only a slight and nonsignificant decrease was noted in the fatty acid content over this period of time. Therefore, freeze-drying may be an effective way of preserving the eggs in excess, at least up to 58 wk of storage.  相似文献   
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Histological examination was performed in 123 cats with primary nasal and paranasal sinus tumours; 117 had undergone surgical biopsy and six necropsy. Special stains and immunohistochemistry were performed on poorly differentiated cases. Ninety-two percent (113/123) of the tumours were malignant. There was an increased risk for old cats (mean age of 10.9 years), and a male predilection (59% males). Clinical signs and breeds varied with the histological type of tumour. Thirty-nine percent (48/123) of the cases presented with nasal discharge, 21% (26/123) with dyspnea, 20% (24/123) with facial swelling, and 15% (19/123) with epistaxis. Forty-three percent (53/123) of the tumours were of epithelial origin. Adenocarcinomas (18/53) and squamous cell carcinomas (17/53) were the most common epithelial tumours. Fifty percent (26/53) of the epithelial tumours originated from the pseudo-stratified respiratory epithelium of the nasal cavity, 28% (15/53) from the stratified squamous epithelium of the vestibule, 9% (5/53) from olfactory epithelium, 9% (5/53) from submucosal glands and 4% (2/53) from minor salivary glands. Malignant lymphoma (35/123) was the most common tumour. Seventy-one percent (25/35) of the malignant lymphomas were B-cell tumours and 29% (10/35) were T-cell tumours. Six cases of malignant lymphomas were proved to be epitheliotropic T-cell lymphomas. This is the first report of a primary nasal epitheliotropic T-cell lymphoma in cats.  相似文献   
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The identification of Leptospira clinical isolates through genotyping and serotyping, besides the recognition of its reservoirs, are important tools for understanding the epidemiology of leptospirosis, and they are also keys for identifying new species and serovars. Fourteen clinical isolates from animals were characterized by means of single enzyme amplified length polymorphism, variable number of tandem repeat analysis, pulsed field gel electrophoresis, and serotyping. All isolates were identified as Leptospira interrogans, serovar Canicola. Infections by this serovar occur in urban regions, where dogs represent the main maintenance hosts, whereas bovine and swine may act as reservoirs of serovar Canicola in rural areas. Both urban and rural aspects of leptospirosis, and the role of domestic animals as maintenance hosts, cannot be neglected in developing and developed countries.  相似文献   
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