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Tropical Animal Health and Production - We aimed to evaluate the chemical composition, production yield, and economic viability of Minas Frescal cheese produced with milk from buffaloes...  相似文献   
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Raw soybean flour contains high levels of both soybean trypsin inhibitor and unsaturated fat. The chronic ingestion of this flour enhances pancreatic carcinogenesis in rats that have been treated with pancreatic carcinogens. In these studies we have examined the separate and combined effects of trypsin inhibitor in purified soybean isolate (SBI) and a high level of unsaturated fat fed during the postinitiation phase of pancreatic carcinogenesis. Male Wistar rats were injected with the known pancreatic carcinogen azaserine (30 mg/kg, ip) 14 days after birth and were weaned to the test diets. No further exposure to carcinogen occurred. Dietary composition (% by weight) of fat (corn oil) was either 5%, or for the high fat group 20%. Dietary protein (20% in all diets) was supplied as either casein, or heated or raw SBI. All diets were fedad libitum for the postinitiation phase. The number and size of transections of azaserine-induced putative, preneoplastic foci and the volume of pancreas occupied by these foci were determined by light microscopy. High fat diet increased the number and transectional size of the azaserine-induced foci as compared to the control (5% corn oil) group. The volume of pancreas occupied by foci doubled. Heated SBI had no effect upon the foci. Raw SBI, however, significantly increased the number and size of foci. The combination of raw SBI plus the high fat diet elicited an increase in focal growth that was greater than that produced by either component alone. These observations indicated that both trypsin inhibitor and the high unsaturated fat content of raw soy flour contribute to the enhancement or promotion of pancreatic carcinogenesis.  相似文献   
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Extreme eosinophilia with disseminated eosinophilic granulomatous disease is described in a 4-year-old Arabian mare. Clinical signs included weight loss, coughing, jugular distention, and ventral edema. Cutaneous lesions were not observed. Eosinophilic inflammation was observed in cytologic specimens from the respiratory tract, body cavities, and lymph nodes. At necropsy, a 20-cm diameter intrathoracic mass was observed. Smaller nodules were present in the lymph nodes, liver, spleen, adrenal glands, pancreas, and skeletal muscle. Histologically, these masses and nodules were characterized by infiltrates of eosinophils, macrophages, and multinucleated giant cells, reactive fibroplasia; and multifocal eosinophilic coagula. Microscopically, mild eosinophilic infiltrates were observed in sections of stomach, small intestine, colon, and pleura; however, gross lesions were not observed in these tissues at necropsy. The etiology of the extreme eosinophilia and disseminated eosinophilic granulomatous disease in this horse was not determined.  相似文献   
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OBJECTIVE: To determine the percentage of broodmares and foals that shed Clostridium perfringens in their feces and classify the genotypes of those isolates. DESIGN: Prospective cross-sectional study. ANIMALS: 128 broodmares and their foals on 6 equine premises. PROCEDURES: Anaerobic and aerobic bacteriologic cultures were performed on feces collected 3 times from broodmares and foals. All isolates of C. perfringens were genotyped. RESULTS: Clostridium perfringens was isolated from the feces of 90% of 3-day-old foals and 64% of foals at 8 to 12 hours of age. A lower percentage of broodmares and 1- to 2-month-old foals shed C. perfringens in their feces, compared with neonatal foals. Among samples with positive results, C. perfringens type A was the most common genotype identified (85%); C. perfringens type A with the beta2 toxin gene was identified in 12% of samples, C. perfringens type A with the enterotoxin gene was identified in 2.1% of samples, and C. perfringens type C was identified in < 1% of samples. CONCLUSIONS AND CLINICAL RELEVANCE: Clostridium perfringens was identified from the feces of all but 6 foals by 3 days of age and is likely part of the normal microflora of neonatal foals. Most isolates from broodmares and foals are C. perfringens type A; thus, the clinical relevance of culture results alone is questionable. Clostridium perfringens type C, which has been associated with neonatal enterocolitis, is rarely found in the feces of horses.  相似文献   
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A novel pox virus, condorpox virus (CPV) isolated from the spleen of an Andean condor (Vultur gryphus) by inoculation of chorioallantoic membranes (CAM) of specific pathogen free (SPF) chicken embryos was compared biologically, antigenically and genetically with fowlpox virus (FPV), the type species of the genus Avipoxvirus. Susceptible chickens inoculated with CPV developed only mild localized lesions but were not protected against subsequent challenge with FPV. Based on Western blotting, in addition to the presence of cross-reacting antigens, distinct differences in antigenic profiles of CPV and FPV were observed. Sequence analysis of a 4.5 kb HindIII fragment of CPV genomic DNA revealed the presence of eight co-linear genes corresponding to FPV open reading frame (ORF)193-198, 201 and 203. Interestingly, reticuloendotheliosis virus (REV) sequences present in the genome of all FPV were absent in CPV. Although, the results of a phylogenic analysis suggested that CPV is a member of the genus Avipoxvirus, its unique antigenic, biologic and genetic characteristics distinguish it from FPV to be considered as a new member of this genus.  相似文献   
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Piscirickettsia salmonisis the causative bacterial pathogen of piscirickettsiosis, a salmonid disease that causes notable mortalities in the worldwide aquaculture industry. Published research describes the phenotypic traits, virulence factors, pathogenicity and antibiotic‐resistance potential for various P. salmonisstrains. However, evolutionary and genetic information is scarce for P. salmonis. The present study used multilocus sequence typing (MLST) to gain insight into the population structure and evolution of P. salmonis. Forty‐two Chilean P. salmonisisolates, as well as the type strain LF‐89T, were recovered from diseased Salmo salar, Oncorhynchus kisutchand Oncorhynchus mykissfrom two Chilean Regions. MLST assessed the loci sequences of dnaK, efp, fumC, glyA, murG, rpoD and trpB. Bioinformatics analyses established the genetic diversity among P. salmonis isolates (H = 0.5810). A total of 23 sequence types (ST) were identified, 53.48% of which were represented by ST1, ST5 and ST2. Population structure analysis through polymorphism patterns showed few polymorphic sites (218 nucleotides from 4,010 bp), while dN/dS ratio analysis indicated purifying selection for dnaK, epf, fumC, murG, and rpoD but neutral selection for the trpB loci. The standardized index of association indicated strong linkage disequilibrium, suggesting clonal population structure. However, recombination events were detected in a group of seven isolates. Findings included genogroups homologous to the LF‐89T and EM‐90 strains, as well as a seven‐isolate hybrid genogroup recovered from both assessed regions (three O. mykiss and four S. salar isolates). The presented MLST scheme has comparative potential, with promising applications in studying distinct P. salmonis isolates (e.g., from different hosts, farms, geographical areas) and in understanding the epidemiology of this pathogen.  相似文献   
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