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851.
The intensity and duration of passive immunity against swine leptospirosis were investigated by the microscopic agglutination test and in vitro leptospira growth inhibition. Twenty-one females at first parturition were divided into three groups: Group A (n=08): received two doses with 30 days interval of the commercial anti-leptospira bacterin A. Group B (n=06) received two doses with 30 days interval of the commercial anti-leptospira bacterin B and Group C (n=07) was the control. In all groups the colostrums were collected. Blood collection of piglets was performed in four different ages. Agglutinin antibodies were equally detected in sera and colostrums for serovars Canicola, Grippotyphosa, Copenhageni, Icterohaemorrhagiae and Pomona (Group A) and Canicola, Copenhageni, Icterohaemorrhagiae, Pomona and Hardjo (Group B). Mean neutralizing antibodies titers were low. Passive immunity was low duration.  相似文献   
852.
An automated method has been developed for the measurement of methaemoglobin (metHb) in blood using a biochemistry analyser. The method was validated using blood collected from red-legged partridges exposed in vitro to increasing concentrations of nitrite in order to obtain different percentages of metHb. Results obtained using the original manual method and those using the new automated technique were compared and no significant differences were found. Intra-day and inter-day variabilities (8.8% and 2.6%, respectively) were acceptable for samples containing high levels (63-81%) of metHb. Methaemoglobin measured in blood samples stored in liquid nitrogen was stable for 10 days, but increased significantly by day 20 in nitrite-treated samples.  相似文献   
853.
Rodents are important in the transmission of infectious diseases that affect the respiratory tract, including simple infections and those caused by specific pathogens. These animals are natural reservoirs of zoonoses that cause many public health diseases. Basic knowledge on the morphology of these animals is important as basic research is useful for applied studies, such as the development of clinical, therapeutic, surgical and clinical models. Morphological data of respiratory tract in Oligoryzomys nigripes are absent in the literature. Therefore, the aim of this study was to perform a morphological analysis of the respiratory tract of O. nigripes. Five adult females from the environmental reserve in São Joaquim da Barra, São Paulo were used, donated to the Museum of Veterinary Anatomy (FMVZ/USP). Several morphological features follow the same pattern seen in rodents; however, this species showed some differences such as the presence of three lobar bronchi, nonlobed left lung and the right lung constituted by two lobes. Respiratory epithelium lined the whole respiratory tract and was seen using scanning electron microscopy the oval shape of the parenchyma and alveoli.  相似文献   
854.
Previously accurate genomic predictions for Bacterial cold water disease (BCWD) resistance in rainbow trout were obtained using a medium‐density single nucleotide polymorphism (SNP) array. Here, the impact of lower‐density SNP panels on the accuracy of genomic predictions was investigated in a commercial rainbow trout breeding population. Using progeny performance data, the accuracy of genomic breeding values (GEBV) using 35K, 10K, 3K, 1K, 500, 300 and 200 SNP panels as well as a panel with 70 quantitative trait loci (QTL)‐flanking SNP was compared. The GEBVs were estimated using the Bayesian method BayesB, single‐step GBLUP (ssGBLUP) and weighted ssGBLUP (wssGBLUP). The accuracy of GEBVs remained high despite the sharp reductions in SNP density, and even with 500 SNP accuracy was higher than the pedigree‐based prediction (0.50–0.56 versus 0.36). Furthermore, the prediction accuracy with the 70 QTL‐flanking SNP (0.65–0.72) was similar to the panel with 35K SNP (0.65–0.71). Genomewide linkage disequilibrium (LD) analysis revealed strong LD (r2 ≥ 0.25) spanning on average over 1 Mb across the rainbow trout genome. This long‐range LD likely contributed to the accurate genomic predictions with the low‐density SNP panels. Population structure analysis supported the hypothesis that long‐range LD in this population may be caused by admixture. Results suggest that lower‐cost, low‐density SNP panels can be used for implementing genomic selection for BCWD resistance in rainbow trout breeding programs.  相似文献   
855.
Spinal spirocercosis due to aberrant Spirocerca lupi nematode migration is an emerging etiology for acute myelitis in dogs in Israel, causing severe, mostly nonsymmetrical hind limb paresis or paralysis, and sometimes tetraparesis or tetraparalysis. So far, incidental identification of parasites during spinal surgery or at necropsy provides the only definite diagnosis, while antemortem diagnosis of this condition has been uncertain. Specifically, antemortem diagnosis is based on the typical clinical presentation of acute, progressive, asymmetrical hind limb paresis or paralysis, with moderate to severe eosinophilic to mixed cerebrospinal fluid (CSF) pleocytosis and increased CSF protein concentration. Exclusion of other differential diagnoses also requires using spinal cord imaging. In this novel report, we document a case of an intradural spinal spirocercosis in a dog, diagnosed antemortem, by detecting S lupi eggs in the CSF, and subsequent treatment, resulting in the resolution of the clinical signs.  相似文献   
856.
To determine the efficacy and safety of subarachnoid butorphanol combined with lidocaine, six calves were studied. Each calf underwent two treatments, at least one week apart, via subarachnoid injection: (1) butorphanol (0.03 mg/kg) plus 2% lidocaine (4 mg/kg) and (2) 2% lidocaine (4 mg/kg) alone. Subarachnoid injections were performed at the lumbosacral space. Analgesia, motor block, sedation, heart rate, arterial blood pressure, respiratory rate, arterial oxygen saturation as measured by pulse oximetry, and rectal temperature were compared before and after subarachnoid administration of drugs. Subarachnoid administration of the butorphanol-lidocaine combination induced bilateral prolonged analgesia extending from the coccygeal to the T11-T13 dermatomes in the calves, with minimal sedation and severe ataxia. Cardiovascular effects were significant in both treatments: heart rate was increased, and there was a minimal decrease in arterial pressure. It was concluded that adding a small dose of butorphanol to subarachnoid lidocaine in calves is effective and safe.  相似文献   
857.
Ultrasonographic (US), magnetic resonance (MR) and computed tomographic (CT) images of normal canine stifle joints were obtained and compared with plastinated cross-sectional slices of cadaver specimens from the same dogs. The bony and articular structures were identified and correlated with the three diagnostic imaging modalities. These results provide an atlas of normal cross-sectional US, MR and CT anatomy of the canine stifle, which can be used for the interpretation of stifle images from any of these imaging modalities.  相似文献   
858.
In addition to Aelurostrongylus abstrusus (Strongylida: Angiostrongylidae), referred to as the feline lungworm, Troglostrongylus brevior (Strongylida: Crenosomatidae) has recently been identified as an agent of bronco-pulmonary infestations in cats. These two parasites have a similar biology, share ecological niches, potentially co-infesting cats, but are difficult to be differentiated due to the morphological similarities of their first-stage larvae (L1). This paper describes a molecular tool, based on single-step duplex polymerase chain reaction (duplex-PCR) on the ribosomal internal transcribed spacer 2 region (ITS-2) for the simultaneous detection and differentiation of T. brevior and A. abstrusus. L1 of both species were collected from faecal samples, morphologically identified, and single larval specimens isolated. An aliquot of faeces was used as a test sample for a case of mixed natural infestation. The duplex-PCR was performed using species-specific forward primer sets for the ITS-2 region (i.e., A. abstrusus: 220 bp; T. brevior: 370 bp). The detection limit of the molecular assay was also assessed by serial dilutions of DNA from single larvae of both species (from ~4.0 to 4.0 × 10?5 μg/μl). The duplex-PCR carried out on individual DNA samples was able to detect as low as 5.2 × 10?3 μg/μl of DNA for A. abstrusus, 4.9 × 10?3 μg/μl for T. brevior, and as low as 4.0 × 10?3 μg/μl for samples containing both species. Species-specific bands of the expected sizes and two bands were simultaneously amplified from the faecal sample containing both species. The phylogenetic analyses of the ITS-2 sequences here examined and those available for other metastrongyloids were concordant in clustering them with those of other Troglostrongylus brevior and A. abstrusus sequences available in GenBank database. This molecular approach proved to be effective and highly sensitive for the simultaneous detection of the two lungworms species and it might be used for molecular epidemiological studies and for monitoring therapeutic protocols.  相似文献   
859.
This investigation reported for the first time the occurrence of intramammary infections caused by Staphylococcus in primiparous replacement goats before parturition and the persistence of clinical Staphylococcus aureus infection during the lactation period. Subclinical infections, mainly caused by coagulase negative staphylococci (CoNS), did not persist during lactation. Genotyping analysis indicated that environment seems to play a moderate role as source of intramammary infections to goats before parturition, but causative agents of mastitis in lactating animals are not genotypically related to environmental staphylococci. The occurrence and persistence of intramammary infections in replacement goats demonstrate the need to consider those animals as potential sources of infections in dairy goat herds.  相似文献   
860.
ObjectiveTo evaluate the possible renal and hepatic toxicity of tepoxalin in dogs exposed to hypotension during isoflurane anesthesia.Study designProspective, randomized experimental study.AnimalsTwenty adult mixed-breed dogs, weighing 18.8 ± 2.8 kg.MethodsThe animals received 10 mg kg?1 tepoxalin orally 2 hours before the anesthetic procedure (PRE; n = 6), or 30 minutes after anesthesia (POST; n = 6), along with a control group (CON; n = 8), which were only anesthetized. The PRE and POST groups also received the same dose of tepoxalin for 5 days post-procedure. All dogs were anesthetized with propofol and maintained with isoflurane and the end-tidal isoflurane (Fe’Iso) was increased until mean arterial pressure decreased to 50–60 mmHg. These pressures were maintained for 60 minutes. Heart rate, arterial pressures and Fe’Iso were recorded at 0, 10 and every 10 minutes up to 60 minutes of hypotension. Blood gases, pH, electrolytes and bleeding time were analyzed before and at 30 and 60 minutes of hypotension. Renal and hepatic changes were quantified by serum and urinary biochemistry and creatinine clearance.ResultsSerum concentrations of alanine amino transferase (ALT), alkaline phosphatase (ALP) and σ-glutamyl transferase (GGT), blood urea nitrogen (BUN) and creatinine (Cr), and urinary output, urinary Cr, Cr clearance, and GGT:Cr ratio remained stable throughout the evaluations. During the anesthetic procedure there were no important variations in the physiological parameters. No side effects were observed in any of the groups.Conclusions and clinical relevanceTepoxalin did not cause significant effects on renal function or cause hepatic injury in healthy dogs exposed to hypotension with isoflurane, when administered pre- or postanesthetic and continued for five consecutive days.  相似文献   
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