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81.
Bilateral nephrolithiasis with intermittent ureterolithiasis was diagnosed in a 7-year old Holstein cow. Two episodes of ureterolithiasis resulted in severe azotemia which resolved after spontaneous movement of the stone. A third episode of obstruction one year after the initial episode resulted in rupture of one kidney, necessitating euthanasia. The histopathological examination of the kidney was diagnostic for chronic pyelonephritis. Corynebacterium sp. was cultured from a nephrolith. In this case it is believed that the chronic pyelonephritis predisposed to the calculi formation.  相似文献   
82.
The efficacy of a new pelleting process in eliminating naturally occurring Escherichia coli and salmonella from poultry mash was assessed by comparing the microbial load in raw and processed mash. Instead of using steam produced in a boiler, the new process conditioned mash in an Original Vertical Conditioner with steam and other hot gases generated by direct combustion in a Vaporator. E. coli was isolated from 72-100% of samples of raw mash in all trials, and the mean number of colony-forming units of E. coli/g of samples was 6.8 +/- 4.0 X 10(4). Salmonellae (S. senftenberg, S. bredeney, and S. mbandaka) were isolated from 5-10% of samples of raw mash utilized in three of the seven trials. Within limitations of the sampling and analytical tests utilized, the new pelleting process eliminated salmonella from all mash in which the organism was known to be present but eliminated E. coli in only three trials. The process appeared to be 100% effective against both organisms when mash entering the pellet mill from the conditioner had a temperature of 85.7 C and a moisture content of 14.5% and had been retained and treated with steam and hot gases for 4.1 minutes.  相似文献   
83.
Pharmacologic effects of alpha-methylfentanyl and 3-methylfentanyl, analogs of fentanyl, were investigated in mares. The ability of an 125I-labeled fentanyl radioimmunoassay (125I-RIA) to detect these methylated fentanyl analogs in individual and pooled urine samples from horses was evaluated. Also, the ability of 7 fentanyl antibodies to react with fentanyl and fentanyl derivatives (sufentanil, alfentanil, and carfentanil) was investigated. Mares were studied in a locomotor test to determine the amount of stimulation methylated fentanyl analogs might induce. Two mares each were given alpha-methylfentanyl at 1, 2, 4, 8, or 13 micrograms/kg of body weight, IV, or 3-methylfentanyl at 0.4, 0.7, or 1 microgram/kg IV. The cross-reactivity of sufentanil, alfentanil, carfentanil, alpha-methylfentanyl, and 3-methylfentanyl with 7 fentanyl antibodies was studied, using the 125I-RIA. All fentanyl analogs, with the exception of alfentanil, cross-reacted well with a C1 antibody raised to fentanyl. Less satisfactory cross-reactivity was determined with 6 other antibodies raised to fentanyl derivatives. When the C1 antibody was combined with an iodinated analog to fentanyl, good detectability of alpha-methylfentanyl and 3-methylfentanyl, in terms of fentanyl equivalents, was obtained from urine samples of dosed mares. The ability of the 125I-RIA to detect methylated fentanyl analogs in forensic urine samples pooled in groups of up to 20 samples was evaluated. When these methylated analogs were administered to mares in doses that induced measurable locomotor stimulation, the analog's presence was readily detected in individual or pooled samples.  相似文献   
84.
Although there are notable infectious conditions that are capable of producing clinical disease in the NWC, overall, these species are quite healthy. Of the bacterial diseases, enterotoxemia caused by Clostridium perfringens types C and D would be deemed the most significant in North America, while type A also would be regarded as important in South America. Other important bacterial infections of potential concern are tuberculosis, Johne's disease, anthrax, malignant edema, actinomycosis, tetanus, and the South American condition referred to as alpaca fever, which, to date, has not been observed in North America. Fungal infections include classical ringworm, principally caused by Trichophyton spp., and the cases of coccidioidomycosis that are associated with the arid desert lands of the southwestern United States. Most notable of naturally occurring viral infections in the NWC would be rabies, ecthyma, and a recently described blindness neuropathy that has been associated with the equine herpesvirus I. NWC can be infected experimentally with agents causing hoof-and-mouth disease and vesicular stomatitis, but naturally occurring cases do not seem to occur. Serological evidence of exposure to many viral agents, including blue tongue, parainfluenza 3, bovine respiratory syncytial virus, bovine herpesvirus I, bovine viral diarrhea, influenza A, and rotavirus, has been demonstrated; however, no clinical disease associated with these agents, as yet, is apparent.  相似文献   
85.
Infectious diseases remain one of the most important limitations to the successful propagation of aquatic animals. Most of the losses caused by pathogens in aquaculture could be prevented by health inspection, adequate environment and sound management practices. Effective control measures, mainly based upon 1) avoidance of pathogens 2) modification of the environment 3) improvement of host resistance 4) vaccination and 5) chemoprophylaxis are described.  相似文献   
86.
An ELISA was developed to detect circulating antigens of Toxoplasma gondii in the serum of cats. For the experiment, toxoplasmosis was induced in a group of cats by oral administration of bradyzoites. An ELISA that detects anti-Toxoplasma IgG, an ELISA to detect circulating antigens, and fecal examinations were performed on samples from each cat for 1 year after inoculation. When coupled with IgG-class antibody measurement, antigen detection can aid in the diagnosis of some cases of subclinical feline toxoplasmosis.  相似文献   
87.
Dairy practice often requires substantial time commitments. Those veterinarians with families may find that if they do not actively budget some time for spouse and children, the family unit may suffer. A successful practice and meaningful family life are both possible if the doctor or doctors involved are willing to work for their achievement.  相似文献   
88.
The kidney's microvascularization of the Pudu pudu is mostly similar to that of domestic animals. The renal parenchymatous arteries do not give off capsular branches. The majority of the Pudu pudu's glomerula shows spherical shape. Glomerula next to the medulla have a diameter which is an average of 25 microns larger than the diameter of those situated more peripherally. Their volume is comparable to that of the angora rabbit. The capillaries form anastomosis in the inner and outer part of the glomerulus.  相似文献   
89.
90.
A total of 739 cattle from nine breeds maintained at the Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, Nebraska were tested for 42 class I antigens of the bovine major histocompatibility system (BoLA). Each antigen appears to be the product of a distinct co-dominant allele of the BoLA-A locus. The number of antigens present in each breed ranged from a minimum of 10 in Hereford to a maximum of 21 in Charolais cattle. There were large differences among breeds in the frequencies of antigens. The effect of each antigen on birth weight, preweaning weight gain and postweaning weight gain was estimated in a gene substitution model. Each breed was analyzed separately. There were significant effects of some BoLA antigens on birth weight, preweaning weight gain and postweaning weight gain, which is consistent with previous reports showing associations between the major histocompatibility system and growth parameters in mice, rats and pigs. However, further research is necessary to confirm these findings and to determine the biological mechanisms underlying these associations.  相似文献   
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