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91.
The effects of subcutaneous administration of a commercially available estradiol 17 beta implant on hematologic values and the chemiluminescence response of neutrophils were evaluated in 14 steers. Chemiluminescence and hematologic values were measured in treated (n = 8) and nontreated (n = 6) steers on days -14, -7, and -1 prior to implantation. Estradiol 17B was implanted into the treated group of steers on day 0, and blood samples were obtained from all steers on days 1, 2, 3, 4, 8, 15, 22, 29, 36, 43, and 50. The concentration of estrogen in serum was significantly (P = 0.0120) higher following implantation. Chemiluminescence and hematologic indices were not significantly affected by either implant status or serum concentrations of estrogen. The results of this study suggested that the use of implants containing estradiol 17 beta for promotion of weight gain in steers will not result in alterations of hematologic values or the neutrophil respiratory burst.  相似文献   
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OBJECTIVE: To describe onset and duration of neuromuscular blockade induced by mivacurium chloride and its associated hemodynamic effects at 3 dosages in healthy dogs. ANIMALS: 7 Labrador Retrievers. PROCEDURE: Anesthesia was induced with thiopental and maintained with halothane in oxygen, and dogs were mechanically ventilated to end-tidal P(CO)2 between 35 and 40 mm Hg. Core temperature, end-tidal P(CO)2, and halothane concentration were kept constant throughout the experiment. Neuromuscular function was assessed by evaluation of the train-of-four response to a supramaximal electrical stimulus of 2 Hz applied to the ulnar nerve every 10 seconds. Blood for determination of plasma cholinesterase activity was obtained prior to administration of mivacurium, a bolus of which was administered IV, using a randomized Latin-square design for dosages of 0.01, 0.02, and 0.05 mg/kg of body weight. RESULTS: All dogs had typical plasma cholinesterase activity. After administration of mivacurium, differences were not evident between groups in heart rate, systolic, mean, or diastolic blood pressure, change at any time in heart rate, systolic, mean, or diastolic blood pressure, or pH. Interval from onset to 100% neuromuscular blockade was 3.92+/-1.70, 2.42+/-0.53, and 1.63+/-0.25 minutes at dosages of 0.01, 0.02, and 0.05 mg/kg, respectively. Duration of measurable neuromuscular blockade was 33.72+/-12.73, 65.38+/-12.82, and 151.0+/-38.50 minutes, respectively. Time of onset and duration of effect differed significantly among dosages. CONCLUSIONS AND CLINICAL RELEVANCE: Mivacurium provides good hemodynamic stability at the dosages tested. In dogs, this drug has a rapid onset and long duration of effect.  相似文献   
95.
The capacitation process of sperm cells involves complex changes in the composition and orientation of molecules at the surface of the sperm cell. Here we focus on the lipid architecture in the sperm plasma membrane and demonstrate that the sperm plasma membrane is not static but is an extremely dynamic structure. Advanced fluoroscopic techniques enabled continuous monitoring of lipid organization in living cells and extremely rapid lipid movements were observed. The orientation of lipids in the sperm plasma membrane changed under capacitative treatments, was found to be sensitive for temperature and also changed upon binding of sperm cells to the zona pellucida. The changes in membrane properties coincided with an activation of protein kinases resulting in tyrosine phosphorylation of specific plasma membrane proteins. The detected membrane changes relate to intrinsic membrane properties such as fluidity, permeability, adhesiveness and fusibility. We think that these results may provide a physiological basis for new assays, able to discriminate between functional and non-physiological sperm cells.  相似文献   
96.
By the radiographic examination of pet and wild birds, veterinary clinicians may relatively easily obtain additional information that can be used routinely in their everyday diagnostic and therapeutic work. The first part of the present review summarizes the basic technical conditions of radiological examinations, analyses the radiographic features of healthy birds, and describes the procedure and radiological indications of contrast radiography.  相似文献   
97.
1. The dietary inclusion of 15 and 25 g/kg mannose was associated with a reduction in the numbers of Salmonella enteritidis (PT4) in the caecal contents of chicks challenged by the food. The same benefit was not recorded for S. infantis, possibly because this strain, unlike S. enteritidis PT4, lacked mannose‐sensitive fimbriae.

2. The addition of 25 g/kg palm kernel meal (PKM), but not 20 g/kg desiccated coconut, to the food reduced the degree of salmonella colonisation in the intestinal tract of broiler chicks given diets contaminated with S. kedougou or S. enteritidis from the day of their arrival from the hatchery.

3. The beneficial effect of PKM was also demonstrated at an inclusion rate of 5 g/kg and was similar for preparations with a particle size of either < 150 μm or < 300 μm.

4. Day‐old birds challenged orally with S. enteritidis and given food supplemented with 25 g/kg PKM, became clear of infection by 3 weeks of age while birds given unsupplemented food remained infected.

5. These preliminary results suggest that the inclusion of PKM, which contains inter alia, oligosaccharides containing mannose, in the diet of chicks may reduce the extent to which the intestine is contaminated with salmonellas.  相似文献   

98.
Intratracheal inoculation of 2 Belgian H3N2-influenza viral strains, isolated from sick swine in the field, caused high fever, anorexia and dyspnoea in unvaccinated swine. The strains are related to the human A/Port Chalmers/1/73 (H3N2)-strain. In a limited study, 2 subunit vaccines, both derived from the human A/Philippines/2/82 (H3N2)-strain, were tested for efficacy in protecting swine against these Belgian field isolates. Vaccine A was a commercial vaccine, vaccine B an experimental vaccine. For evaluation of the efficacy of the vaccines, clinical as well as virological parameters were used. It was found that 2 spaced injections of the experimental vaccine (B) resulted in very high serum hemagglutination-inhibition (HI) titres against the Philippines-strain. Nevertheless, only partial protection was obtained, as indicated by the milder clinical signs and the decreased viral replication at challenge. One injection of the experimental vaccine (B) and 2 spaced injections of the commercial vaccine (A) did not result in any protection at challenge, even though moderate HI titres against the Philippines-strain were obtained. It was concluded that if an H3N2-strain is included in vaccines for use in swine, a strain should be selected which is identical or very closely related to the strain(s) prevalent in the swine population of the country in which the vaccine will be used.  相似文献   
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Ectopic teeth occur because of failure of the first branchial cleft to close during development and are found mostly in young horses. Such dentigerous cysts are often located at the base of the ear, forming a notable swelling with a fistula, as it was the case with the two year old Iceland mare ?Runa?. In order to confirm the diagnosis, x-ray images were taken, which is also necessary to locate the ectopic tooth correctly. While operating, the whole cystic membrane should be removed and it is important to prevent adjacent nerves and blood vessels from damage. Prognosis for complete healing after removing an ectopic tooth is excellent.  相似文献   
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