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891.
The effect of ticlopidine on platelet function, platelet number, mean platelet volume, antithrombin III activity, and fibrinogen was evaluated in 10 laboratory beagles. Ticlopidine (62 mg/kg) significantly inhibited ADP- and collagen-induced platelet aggregation within 2 days of the beginning of oral administration. Collagen-induced platelet 14C-serotonin release was not inhibited by day 9 of medication but was inhibited by day 20 in two of three beagles given medication for 32 days. Significant increases in mean platelet number were observed on days 2 and 5. The trend toward increased platelet number continued until day 16, at which time platelet number began to decrease toward baseline in three of three dogs treated for 32 days. Mean platelet volume (MPV) was significantly decreased compared to baseline on days 5 and 9. In three dogs treated for 32 days, the lowest MPV was observed on day 9 in two dogs and on day 12 in one dog. Significant changes were not observed in antithrombin III activity or fibrinogen with ticlopidine treatment.  相似文献   
892.
Effects of 1 hour of colonic volvulus and 3 hours of reperfusion on concentrations of thromboxane (TXB2) and prostacyclin (6-keto-PGF1 alpha) in portal, pulmonary arterial, and jugular blood were determined by radioimmunoassay to assess the site of production and clearance of these eicosanoids from the circulation in 5 anesthetized ponies. Colonic volvulus had no significant effect on mean arterial pressure or TXB2 concentrations, but significantly (P less than 0.05) increased 6-keto-PGF1 alpha concentrations in all blood samples. Immediately after colonic reperfusion, all eicosanoid concentrations were significantly (P less than 0.05) increased. Then, TXB2 returned to baseline values, whereas 6-keto-PGF1 alpha concentrations remained significantly (P less than 0.05) high for the remainder of the study. Eicosanoid concentrations were significantly (P less than 0.05) greater in portal blood than in pulmonary arterial and jugular blood samples at all periods. This suggests that the splanchnic circulation is the primary site of eicosanoid production during and after colonic volvulus and the liver appears to provide most of the circulatory clearance of thromboxane and prostacyclin.  相似文献   
893.
894.
A Thoroughbred stallion with erectile dysfunction following paraphimosis was managed to allow consistent ejaculation. Ejaculation was elicited in this stallion by applying manual stimulation to the base of the penis. This technique allowed consistent ejaculation, and the stallion was able to return to natural service. Historically, stallions with this degree of penile dysfunction have been considered incapable of ejaculation and unable to continue as breeding animals.  相似文献   
895.
A large fibrotic mass originating from the cecal base was discovered upon surgical exploration of the abdomen in a Thoroughbred mare with a history of chronic colic and weight loss. The mass protruded intraluminally resulting in partial obstruction. Surgical excision was not feasible due to the location of the mass and the inability to exteriorize it adequately from the abdominal cavity. The mass was fibrous with a shiny, gelatinous material present throughout the neoplasm. Histologically, large confluent spaces filled with mucopolysaccharides were identified by staining with Alcian blue. The diagnosis of myxosarcoma was based upon finding of atypical fibroblastic cells, mucinous stroma, local invasiveness, and metastasis to the regional lymph nodes. Myxomatous tumors have not previously been documented to occur in the equine intestinal tract.  相似文献   
896.
Restriction endonuclease analysis of 16 Australian and 4 New Zealand isolates of Leptospira interrogans serovar pomona showed that they could be divided into 3 genetic groups. Most of the isolates closely resembled the serovar kennewicki reference strain, and they all differed from the reference strain of serovar pomona. Based on these findings, it is suggested that vaccine manufacturers re-evaluate their choice of serovar pomona vaccine strain.  相似文献   
897.
Lambs sucking non-immunised ewes or ewes immunised 4-5 weeks before lambing with live attenuated, aromatic-dependent (aroA) Salmonella typhimurium (strain CS 332) were challenged orally at either 2, 4 or 7 days of age with virulent S. typhimurium (strain CS 94) at doses ranging from 109 to 1013 colony forming units. No lambs displayed signs of clinical salmonellosis and all survived challenge but those sucking immunised ewes had organisms of the challenge strain in their faeces for much shorter periods of time than lambs of the control ewes. High titres of specific antibodies were measured in colostrum and milk of immunised ewes in comparison with very low titres measured in samples from control ewes; these differences were reflected by the titres of antibodies in the sera of corresponding lambs. At 2 days after lambing, the major antibody isotype in the colostrum of immunised ewes and sera of their lambs was IgM whereas at 7 days IgG1 was the predominant isotype. While it was clear that vaccination of pregnant ewes with the live attenuated vaccination conferred protection against experimentally-induced salmonellosis in their lambs, considerable protection was observed in control lambs in spite of there being very low titres of antibodies in the mammary secretion of their dams. The latter observation could be related to the presence of contain non-antibody potent bactericidal factors previously described in colostrum and milk.

Résumé

Des agneaux qui tètent des brebis non immunisées, ou bien immunisées, 4 à 5 semaines avant la mise bas avec un vaccin atténué constitué d'une souche de Salmonelle typhimurium dépendente pour sa croissance de la presence de composés aromatiques (souche aro A CS 332) ont reçu, à l'âge de 2, 4 ou 7 jours, par voie orale, des doses allant de 109 à 1013 Salmonella (souche virulente CS 94). Aucun agneau n'a présenté de signes cliniques et tous ont survécu à cette administration, mais les agneaux des brebis immunisées ont excrété la souche d'épreuve dans leur fécès pendent moins longtemps que les agneaux des brebis non vaccinées. Des titres plus élevés d'anticorps sont détectés dans le colostrum et le lait des brebis vaccinées et comparés aux brebis témoins. Cette différence est également notée pour les titres d'anticorps présents dans le sérum des agneaux issus de brebis vaccinées ou non. Deux jours après la mise bas, la classe des anticorps majoritaires, tant au niveau du colostrum des brebis vaccinées que du sérum de leurs agneaux, est la classe des IgM, alors qu'après 7 jours, les IgG1 prédominent. Bien qu'il soit clair que des brebis pleines vaccinées à l'aide d'un vaccin vivant atténué, apportent à leurs agneaux une protection vis à vis d'une Salmonella expérimentale, une réelle protection est également observée chez les agneaux témoins, malgré les titres faibles d'anticorps présente dans les sécrétions mammaires de leur mères. Cette dernière observation peut être mise en rapport avec la présence d'agents bactériodes ne contenant pas d'anticorps, déjà décrits dans le colostrum et le lait.  相似文献   

898.
A presumed genetic syndrome is described in a family of St. Bernards. Four identically affected littermates presented the association of palate agenesis, anotia, incomplete bifid tongue, preaxial hind paw polydactyly, and an extra thoracic vertebra and rib. Pedigree analysis is compatible with an autosomal recessive gene.  相似文献   
899.
We compared the field efficacy of a new antibiotic, florfenicol, with tilmicosin in the treatment of naturally occurring undifferentiated bovine respiratory disease. Beef calves with rectal temperatures greater than 40.5 degrees C and signs compatible with undifferentiated bovine respiratory disease were entered into the trial. Calves were randomly assigned to receive either florfenicol (20 mg/kg bodyweight intramuscularly; 2 injections 48 h apart) or tilmicosin (10 mg/kg bodyweight subcutaneously; 1 injection). Clinical measures of efficacy included mortality, rectal temperature, illness index score, assessment of treatment success or failure, and the number of relapses or reinfections. Performance was assessed based on weight gains from day 0 to day 90. Two hundred and twenty calves entered the trial; 112 received florfenicol and 108 received tilmicosin. Seventeen deaths occurred between day 0 and day 90, but only 10 during the 28-day trial period. Seven calves receiving tilmicosin died, compared with 3 receiving florfenicol (P = 0.20). Of the 220 initial treatments, 45 (20%) were categorized as treatment failures; 27 in the tilmicosin group and 18 in the florfenicol group (P = 0.10). The number of calves experiencing a 2nd relapse was significantly different, with 17 of 30 (57%) calves on tilmicosin compared with 7 of 26 (27%) calves on florfenicol relapsing at least twice (P = 0.02). Average daily gains over 90 days were 1.55 kg/day for florfenicol-treated calves and 1.51 kg/day for tilmicosin-treated calves. No significant adverse reactions were noticed with either drug. Results indicate that florfenicol and tilmicosin are comparable in the treatment of undifferentiated bovine respiratory disease in western Canada.  相似文献   
900.
Glycosylated albumin and glycosylated protein in serum were measured in 4 well-controlled diabetic dogs, 4 poorly controlled diabetic dogs, and 21 nondiabetic dogs. Concentrations of both glycosylated components in the well-controlled dogs were similar to those in nondiabetic dogs. Serum concentrations of glycosylated albumin and protein in the poorly controlled diabetic dogs were higher (P less than 0.001) than those of the nondiabetic and well-controlled diabetic dogs. Because of the essentially irreversible nature of the glycosylation reaction and the relatively short turnover time of albumin and other serum proteins, measurements of glycosylated serum components may provide an index of glycemia during the preceding days or weeks.  相似文献   
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