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91.

The aim of the present study was to describe the strategies of the control of an outbreak of leptospiral infection in dairy cattle in Maranhão State, Northeastern Brazil. In the period from January to July 2015, 18 (17%) out of 106 cows presented abortion, six (5.7%) stillbirth, and 12 (11.3%) repeated estrus, totaling 24 animals with reproductive problems. The diagnosis of leptospirosis was based on serology (microscopic agglutination test—MAT), bacteriological culture, and polymerase chain reaction (PCR). Antibiotic therapy, vaccination protocols, and changes in management practices were suggested as control measures. Of all animals on the farm (n?=?280), 136 (48.6%) were seropositive for at least one serovar of Leptospira sp. No pure leptospiral culture was obtained. Eight of the animals with reproductive problems yielded positive PCR results (vaginal fluid of seven animals and urine and vaginal fluid of one animal). Genetic sequencing of a vaginal fluid/urine PCR-positive sample revealed Leptospira borgpetersenii. One year after the adoption of control measures, no reproductive problems were observed. Thus, leptospirosis probably caused the reproductive failures in the herd, and the control and prevention measures implemented were efficient in controlling the disease.

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Tropical Animal Health and Production - The objective of this study was to evaluate the effect of the replacement of corn by cassava dregs (0, 33, 66, and 100%) in the diet of lamb on...  相似文献   
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Tropical Animal Health and Production - The objective of this study was to evaluate the ruminal parameters (pH, N-NH3, and microbial protein) and morphometry of the rumen and intestine of sheep fed...  相似文献   
96.
Osteosarcoma is the most commonly reported bone tumor in dogs, typically affecting the axial and appendicular skeleton. Involvement of the paranasal sinuses and the nasal cavity is extremely rare. This report describes a 6-year-old, female, cross-breed dog presented with signs of 90 days duration and diagnosed with a mass located in the right nasal cavity. Radiography, rhinoscopy, and computed tomography findings suggested the presence of an intranasal tumor. Osteosarcoma in the nasal cavity was diagnosed based on histopathological examination and clinical and imaging findings. Survival time was 12 months from diagnosis.  相似文献   
97.
Salmonella Dublin is strongly adapted to cattle causing enteritis and/or systemic disease with high rates of mortality. However, it can be sporadically isolated from humans, usually causing serious disease, especially in patients with underlying chronic diseases. The aim of this study was to molecularly type S. Dublin strains isolated from humans and animals in Brazil to verify the diversity of these strains as well as to ascertain possible differences between strains isolated from humans and animals. Moreover, the presence of the capsular antigen Vi and the plasmid profile was characterized in addition to the anti‐microbial resistance against 15 drugs. For this reason, 113 S. Dublin strains isolated between 1983 and 2016 from humans (83) and animals (30) in Brazil were typed by PFGE and MLVA. The presence of the capsular antigen Vi was verified by PCR, and the phenotypic expression of the capsular antigen was determined serologically. Also, a plasmid analysis for each strain was carried out. The strains studied were divided into 35 different PFGE types and 89 MLVA‐types with a similarity of ≥80% and ≥17.5%, respectively. The plasmid sizes found ranged from 2 to >150 kb and none of the strains studied presented the capsular antigen Vi. Resistance or intermediate resistance was found in 23 strains (20.3%) that were resistant to ampicillin, ciprofloxacin, chloramphenicol, imipenem, nalidixic acid, piperacillin, streptomycin and/or tetracycline. The majority of the S. Dublin strains studied and isolated over a 33‐year period may descend from a common subtype that has been contaminating humans and animals in Brazil and able to cause invasive disease even in the absence of the capsular antigen. The higher diversity of resistance phenotypes in human isolates, as compared with animal strains, may be a reflection of the different anti‐microbial treatments used to control S. Dublin infections in humans in Brazil.  相似文献   
98.
A differential pulse polarographic method has been developed for the indirect determination of diacetyl and other vicinal diketones in foodstuffs, based on the quantitative derivatization of the diketones with o-phenylenediamine to give quinoxalines. The method allows the identification of diacetyl and methylglyoxal in brandy, vinegar, wine, and butter samples. The polarographic reduction peaks of the quinoxalines formed are sufficiently separate, in some cases, to allow the simultaneous determination of these two compounds. The polarographic method is not affected by the presence of sulfite ion, probably because the o-phenylenediamine is capable of dislodging the alpha-diketones from their sulfite complexes.  相似文献   
99.
The objective of this experiment was to test the probiotic Efinol®L during transportation of cardinal tetra, Paracheirodon axelrodi (Schultz). For the transportation, fish were distributed in 18 plastic tanks, of which nine contained the Efinol®L (10 mg L−1; probiotic treatment) and the remaining had no probiotic (control treatment). Transport lasted 24 h and three different boxes of each treatment were sampled at 3, 12 and 24 h. Up to the 12-h sampling period, no significant difference in the survival was observed; on the other hand, survival was higher at the end of the transport (24 h) in the probiotic treatment. No significant difference was found in dissolved oxygen and temperature between treatments. Conductivity, pH and alkalinity increased along the transport, but without a difference between treatments. Ammonia increased in all treatments, although it was significantly lower in the probiotic group at 24 h. Cortisol levels were significantly higher in all transported fish when compared with the basal values. At 24 h, cortisol levels in control fish were significantly higher than those in the probiotic treatment. With the observed results, we are able to conclude that the probiotic Efinol®L is efficient during cardinal transport, lowering the mortality and helping maintain water quality possibly by lowering metabolic wastes.  相似文献   
100.
This study evaluated the impact of pond management on tambaqui, Colossoma macropomum (Cuvier), rearing during the growout phase. Juvenile tambaqui were stocked in ponds with three different management regimes: (1) natural ponds (Nat); (2) limed ponds (Lim); and (3) limed and bimonthly fertilized ponds (LimFer). The experiment lasted 210 days and the growth parameters were evaluated monthly. Water quality and effluent measurements were performed every 15 days and at the end of the experiment yield parameters were obtained. There was no difference in weight and length among treatments. Stomach contents and zooplankton availability were not influenced by pond management, but the rearing period had an influence on them. Food conversion rate (FCR) was better in fish from the Lim treatment than in fish from the Nat treatment. The pH, hardness and alkalinity values were significantly higher in the Lim and LimFer ponds, where the liming procedure was performed. The effluent analysis showed a more potentially impacting effluent in the LimFer treatment, where phosphorus and orthophosphate concentrations showed values significantly higher than those in Lim and Nat ponds. The results show that the Lim treatment is the best approach, as in this treatment fish achieve market size, better FCR, yield and have a reduced environmental impact.  相似文献   
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