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991.
The number of spermatozoa required to obtain conception by intratubal insemination in dogs was examined. Three groups consisting of 5, 8 and 8 dogs received 0.5 x 10 (6), 2.0 x 10(6) and 4.0 x 10(6) spermatozoa, respectively, into each uterine tube. No conception occurred in the 5 animals inseminated with 0.5 x 10(6) spermatozoa, but conception occurred in 6/8 (75.0%) and 3/8 (37.5%) dogs inseminated with 2.0 x 10(6) and 4.0 x 10 (6) spermatozoa, respectively. Among the pregnant animals, three aborted (33.3%) and the mean number of newborns was small, 2.5 +/- 0.5 (SE). One acardiacus anceps was observed with normal fetus in one animal with a Caesarean delivery.  相似文献   
992.
Immune system is organized by the influence of both neural and endocrine systems. NK activity plays an important role in the innate immunity. In this study, we observed the effects of restraint stress on chicken peripheral blood NK activity. Viability of FITC-labeled RP9 was measured with PI after treatment with the effector cells. Chicken peripheral blood CD8alpha+ cells expressed strong cytotoxic activity, in contrast to thrombocytes, while peripheral blood CD3+ CD8alpha+ cells and CD4+ cells had little cytotoxic activity. Con A supernatant enhanced the cytotoxic activity of CD8alpha+ cells. Therefore, it is considered that these cytotoxic activities measured by flow cytometry (FCM) analysis are NK activity. When chickens were exposed to restraint stress, the levels of serum corticosterone increased transiently over a short period of time while the NK activity decreased. The decreased NK activity, however, did not recover to the intact levels for a long time, even once the serum corticosterone levels had recovered. These data indicate that chicken NK activity is able to be measured by flow cytometric analysis and that restraint stress causes severe damage to the chicken NK activity.  相似文献   
993.
Skulls of the red-cheeked squirrel (Dremomys rufigenis) from various geographical locations: Malaysia (peninsular area), Vietnam (south district)-Laos, and Thailand (north district) were osteometrically examined. The skull size of the squirrels in the southern (Malaysia) population was fundamentally larger than that in the northern (Vietnam, Laos and Thailand) populations. The proportion indices indicated that the splanchnocranium was relatively longer in the Malaysia population, and that the interorbital space was narrower in Vietnam-Laos, and Thailand populations. We suggest that the long nose and laterally-oriented orbits in the skull may be better adapted for terrestrial-insectivorous life in the Malaysia population and the binocular sense facilitated by rostrally-oriented eyes contributes to the arboreal-fruit eating behavior in the two northern populations. The Malaysia population was clearly distinguished from the other populations by the principal component analysis. We suggest that the geographical barrier of the Isthmus of Kra influences the morphological variation of the skull among the squirrel populations.  相似文献   
994.
A 6-month-old male golden retriever was presented with fever, bloody-watery diarrhea and mild cough. Parvovirus and Isospora canis infection was confirmed and successfully treated. Two weeks later, the dog had severe cough and mucopurulent nasal discharge. Aspergillus niger was cultured from endotracheal washings on blood agar at 37 degrees C. Treatment with itraconazole for about 10 weeks resolved the clinical signs.  相似文献   
995.
The platelet function analyser PFA-100 aspirates blood in vitro from a sample reservoir in disposable test cartridges through a microscopic aperture cut into a biologically active membrane at the end of a capillary. In different cartridges the membrane is coated with collagen and adenosine diphosphate (ADP) or collagen and epinephrine (adrenaline) inducing a platelet plug and closure of the aperture. The closure time and total volume of blood flow through the capillary until closure of its aperture were measured. The correlation between platelet count in samples of thrombocytopenic dogs and results of the collagen/ADP cartridge (closure time: r(S)=-0.579; total volume: r(S)=-0.549) was closer than between platelet count and capillary bleeding time. No significant correlation was observed between platelet count and the results obtained with the collagen/epinephrine cartridge. In addition, a higher sensitivity was obtained for the collagen/ADP cartridge. Injection of acetylsalicylic acid into healthy dogs significantly increased closure time and total volume of both types of cartridges (P<0.01). Two dogs with von Willebrand's disease had abnormal values. In contrast, coagulopathies did not significantly influence the results of the platelet function analyser (P>0.05). Despite adequate sensitivity of measurements using the collagen/ADP cartridge to assess quantitative and qualitative platelet disorders in dogs, the influence of haematocrit (P<0.0001) will limit the clinical application of the analyser.  相似文献   
996.
Three single oral doses (8.5, 10, and 14 mg/kg) of a racemic formulation of albendazole sulphoxide (ABZSO) were administered to pregnant rats on day 10 of gestation. Mother plasma and embryo concentrations of ABZSO enantiomers and albendazole sulphone (ABZSO(2)) were determined 9 h after administration. The (-)-ABZSO enantiomer showed higher peak concentrations in both maternal plasma and embryo than the (+) enantiomer. An increase in embryo concentrations of ABZSO enantiomers and ABZSO(2) was only observed when dose rose to 14 mg/kg. There was an increase in resorption when the dose increased, but significant differences were only found in the higher dose group when compared with the other groups. The incidence of external and skeletal malformations (mostly of the tail, vertebrae and ribs) rose significantly in the 10 mg/kg group, producing almost 20% and 90% of malformed fetuses, respectively, and gross external and skeletal abnormalities in the thoracic region and limbs were also found.  相似文献   
997.
Objective To evaluate seasonal effects on the presence or absence of fungal and aerobic bacterial flora of the conjunctival fornix of normal Florida Thoroughbred horses. Sample population Both eyes of 100 horses. Procedure Horses with normal anterior segment ophthalmic examinations from three farms in north central Florida were included. Each animal had the ventral conjunctival fornix of each eye swabbed with sterile culturettes. Samples were taken in October, January, April, and July (1999–2000). Aerobic and fungal cultures were plated. Bacterial cultures were reviewed at 24 and 48 h. Fungal cultures were reviewed weekly for 4 weeks. Logistic regression analysis with season as a factor and age of the horse as a covariate was performed. Statistical significance was set at P < 0.01. Results Horses ranged from 3 to 24 years of age, with a median age of 9 years. Twenty‐four genera of bacteria and 35 genera of fungi were recovered. Corynebacterium sp., Staphylococcus sp., Bacillus sp. and Moraxella sp. were the bacteria most frequently isolated. Mold species, dematiaceous mold species, Chrysosporium sp., Cladosporium sp., and Aspergillus sp. were the most frequently recovered fungi. Season did not have a significant effect on the presence of microorganisms isolated for individual horses adjusted for age. Younger horses had an increased incidence of gram‐negative rods and fungal isolates. The number of bacteria and fungi isolated are not uniform across seasons. Conclusion There were no significant differences between the number or type of organisms cultured during the sampling seasons in normal Florida horses. A large range of normal bacterial and fungal flora were isolated from these horses. The number of bacteria and fungi isolated are not uniform across seasons. The likelihood of detecting an organism depends on the horses’ age.  相似文献   
998.
This article reports an outbreak of 24 cases of an unusually virulent feline calicivirus (FCV) infection in a small animal hospital. The circumstances and disease signs were very similar to those recently described in an outbreak of FCV hemorrhagic disease in Northern California (Vet. Microbiol. 73 (2000) 281). The virus entered the facility through shelter cats showing upper respiratory signs. Affected cats manifested high fever, anorexia, labored respirations, oral ulceration, facial and limb edema, icterus, and pancreatitis. The infection spread rapidly among the patients by contaminated animal caretakers and hospital equipment. One case of fomite transmission from an employee to a housecat was documented. Prior vaccination, even with multiple doses of FCV-F9-based live calicivirus vaccine, was not protective. Affected cats often required extensive supportive care for 7-10 days, and the overall mortality from death and euthanasia was 32%. The strain of FCV responsible for this outbreak was genetically and serologically distinct from the FCV strain responsible for a similar epizootic and the FCV-F9 strain contained in most vaccines. Outbreaks of this type are being reported with increasing frequency, and are often associated with the practice of treating sick shelter cats in private practices. Similar to the present epizootic, outbreaks of FCV hemorrhagic disease have been self-limiting, but require prompt application of strict quarantine, isolation, personnel sanitation, and disinfection procedures.  相似文献   
999.
Propofol is an injectable anaesthetic that is currently used both in veterinary and human medicine for the induction and maintenance of anaesthesia. Although little is known about the pharmacokinetics of propofol in fetuses, it is widely used in obstetric procedures, particularly in caesarean section. This study determines the pharmacokinetics of propofol in pregnant ewes in the last third of pregnancy, and placental transfer and pharmacokinetics in fetuses after the administration of a 6 mg/kg intravenous (i.v.) bolus (phase 1) or a 6 mg/kg i.v. bolus followed by continued infusion of 0.4 mg/kg/min. In ewes, the area under the blood concentration-time curve (AUC) and C(max) (8.6 mgh/mL and 9.5mg/mL, respectively) was higher than those of the fetus (1.6 mgh/mL and 1.19 mg/mL, respectively). The mean half-life was 0.5h in the dam and 1.1h in the fetus.  相似文献   
1000.
Many factors including drugs can influence thyroid function in humans, rats and dogs. Studies in humans report significant effects of non-steroidal anti-inflammatory agents (NSAIDs) on thyroid function tests, which can lead to misinterpretation of the results and inappropriate therapeutic decisions. As NSAIDs are used more and more frequently in dogs, it is important to know to what extent they can influence results. Eighteen spayed female beagle dogs were randomly assigned to three treatment sequences in a 3 x 3 crossover study design with treatments consisting of acetylsalicylic acid (ASA) (25 mg/kg BW q 12 h), ketoprofen (Keto) (1 mg/kg BW q 24 h) or placebo administered for a 1-week period with a 3-week washout period between treatment periods. Blood samples for determination of total thyroxine (TT4), free thyroxine (FT4), total triiodothyronine (TT3), thyrotropin (TSH), reverse triiodothyronine (rT3), Keto and ASA concentrations were taken during each treatment period on days 0, 1, 3 and 7. During the washout period samples were taken weekly. A significant decrease in TT4 was observed as soon as 24 h after ASA administration, whereas the decrease in TT3 was less pronounced and differed significantly from the placebo only after 1 week of administration. No significant effects were found for free T4 and TSH with ASA administration. No significant effects on thyroid results were found following Keto administration. The results indicate that TT4 can be markedly decreased by ASA therapy and until the results of further studies are available, thyroid function test results should be interpreted cautiously in dogs on NSAIDs therapy.  相似文献   
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