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41.
42.
Brownlie J Nuttall PA Stott EJ Taylor G Thomas LH 《Veterinary immunology and immunopathology》1980,1(4):371-378
Certain immunological responses of 4-6 month old calves experimentally inoculated with either cytopathic or non-cytopathic bovine virus diarrhoea virus (BVDV) were compared with those of uninfected control calves. The tests used to demonstrate the immunological responses were the transformation of lymphocytes by PHA mitogen, the percentage of lymphocytes with surface immunoglobulin, and the antibody titres induced by an intravenous inoculation of killed Brucella abortus. There were no significant differences between the two groups of calves and therefore, the mild experimental disease produced by BVDV did not appear to affect adversely the immunological response. 相似文献
43.
Taylor PM 《Veterinary surgery : VS》1999,28(1):77-82
OBJECTIVE: To investigate whether hypertonic saline infusion would prevent hypotension and pituitary-adrenocortical axis activation during halothane anesthesia after acepromazine premedication and thiopental induction in sheep. STUDY DESIGN: Randomized crossover study. ANIMALS: Six Welsh Mountain ewes weighing 40+/-2 kg and aged 2 to 3 years. METHODS: The sheep were studied on two occasions with 2 weeks between anesthetics. After acepromazine premedication, anesthesia was induced with thiopental and maintained for 120 minutes with halothane. During the first 15 minutes of anesthesia, 7.5% saline (4 mL/kg) was infused intravenously (HS group), but no infusion was given in the control (CONT) group. Sequential blood samples were taken for blood gas, cortisol, adenocorticotropic hormone (ACTH), glucose, and lactate assay. RESULTS: Hypotension developed in both treatments; blood pressure decreased to a nadir of 58+/-5 mm Hg in the HS group and to 63+/-4 mm Hg in the CONT group (P>.05). Plasma cortisol increased significantly in both groups, reaching a peak of 420+/-130 nmol/L in HS and 483+/-157 nmol/L in CONT (P>.05). ACTH increased similarly in both groups, reaching 128+/-64 pmol/L in HS and 134+/-55 pmol/L in CONT (P>.05). pH was slightly higher in CONT, but no other differences were detected between the two groups. CONCLUSIONS: Hypertonic saline did not ameliorate the adrenocortical response during anesthesia; this may be a result of its failure to prevent the hypotension. 相似文献
44.
Waldron DF Taylor CA Walker JW Campbell ES Lupton CJ Willingham TD Landau SY 《Journal of animal science》2009,87(2):491-495
Data from goats (n = 505), collected over a 4-yr period, were used to estimate the heritability of juniper consumption. Juniper consumption was determined by near-infrared spectroscopy on fecal samples (n = 1,080) collected from female Boer-cross goats grazing pastures with a variety of plants, including juniper. The animals with records were progeny of 72 sires. Individual goats had from 1 to 4 observations over a 4-yr period. Predicted juniper consumption for individual observations ranged from -5 to +62% of the diet. Data were analyzed with a mixed model that included management group as a fixed effect, BW as a covariate, and permanent environment, animal, and residual as random effects. Management group was a significant source of variation. Least squares means of juniper consumption, as a percentage of the total intake, for management groups varied from 19 to 47%. Heritability of juniper consumption was 13%. Repeatability of juniper consumption was 31%. These results suggest that progress to selection for goats that will consume greater amounts of juniper is obtainable, but is expected to be slow. 相似文献
45.
46.
Meyer AM Reed JJ Neville TL Taylor JB Reynolds LP Redmer DA Vonnahme KA Caton JS 《Journal of animal science》2012,90(8):2733-2749
Objectives were to investigate effects of nutritional plane and Se supply during gestation on visceral organ mass and intestinal growth and vascularization in ewes at parturition and during early lactation. Primiparous Rambouillet ewes (n = 84) were allocated to 2 × 3 × 2 factorial arrangement of treatments. Factors included dietary Se [adequate Se (ASe, 11.5 μg/kg BW) or high Se (HSe, 77.0 μg/kg BW)], nutritional plane [60% (restricted; RES), 100% (control; CON), or 140% (high; HIH)], and physiological stage at necropsy (parturition or d 20 of lactation). At parturition, lambs were removed and 42 ewes (7 per treatment) were necropsied. Remaining ewes were transitioned to a common diet which met lactation requirements and mechanically milked for 20 d. In the absence of interactions (P > 0.10), main effects are reported. At parturition, stomach complex and liver masses were greatest for HIH, intermediate for CON, and least for RES (P < 0.02). Small intestinal mass was greater (P ≤ 0.002) for HIH than RES and CON, and greater (P < 0.01) for ASe than HSe. During early lactation, RES and CON gastrointestinal masses increased disproportionally to BW (P < 0.05). At parturition, jejunal mucosal density was less (P ≤ 0.01) for RES than CON and HIH, whereas CON had greater (P < 0.003) jejunal mucosal RNA concentration and RNA:DNA than RES and HIH. Although there were no differences (P > 0.17) at parturition, jejunal cell percent proliferation was greatest in RES, intermediate in CON, and least in HIH (P ≤ 0.09) at d 20 lactation. At both stages, RES had less (P = 0.01) jejunal capillary area density than HIH and less (P ≤ 0.03) capillary surface density than CON and HIH. During lactation, jejunal capillary size was greater (P = 0.04) for ewes previously fed HSe compared with ASe. At parturition, ASe-HIH had greater (P < 0.02) jejunal mucosal endothelial nitric oxide synthase 3 mRNA than all other treatments and greater (P = 0.10) vascular endothelial growth factor (VEGF) than all treatments, except ASe-RES. In addition, CON had less (P ≤ 0.08) jejunal VEGF receptor-1 (FLT1) mRNA compared with RES and HIH, and ASe had greater (P = 0.003) FLT1 than HSe at parturition. Ewes fed HIH had greater (P = 0.04) jejunal VEGF receptor-2 mRNA compared with RES. Results indicate that maternal intestinal growth and vascularization are responsive to nutritional plane and dietary Se during gestation and undergo changes postpartum when under similar lactational management. 相似文献
47.
Fletcher DJ Snyder JM Messinger JS Chiu AG Vite CH 《Journal of the American Veterinary Medical Association》2006,229(2):240-245
CASE DESCRIPTION: A 4-year-old sexually intact female French Bulldog was evaluated because of lethargy, anorexia, and chronic rhinitis-sinusitis. The dog had nasal discharge of 18 months' duration; dorsal rhinotomies were performed 3 months and 2 weeks prior to referral. CLINICAL FINDINGS: On initial evaluation, intraventricular pneumocephalus and sinusitis were diagnosed; CSF analysis revealed high total protein concentration and mononuclear pleocytosis. The dog's condition improved with treatment. Two weeks after discharge, it was treated by a local veterinarian because of upper airway obstruction; 3 days later, the dog was referred because of seizures. Computed tomography revealed a large fluid-filled, left lateral ventricle and a soft tissue mass protruding through a cribriform plate defect. The mass was histologically consistent with brain tissue. Findings of clinicopathologic analyses were unremarkable. Results of cytologic examination of a CSF sample were indicative of septic, suppurative inflammation, and bacteriologic culture of CSF yielded Escherichia coli. TREATMENT AND OUTCOME: Amputation of the herniated olfactory bulb and antimicrobial treatment resolved the septic meningoencephalitis, but neurologic deficits recurred 6 weeks later. Definitive correction of the cribriform plate defect with bone and fascial grafts was attempted. Postoperative rotation of the bone graft resulted in cerebral laceration and hemorrhage, and the dog was euthanized. CLINICAL RELEVANCE: Findings suggest that following dorsal rhinotomy and nasal polypectomy surgery, the dog developed herniation of the left olfactory bulb, intra-ventricular pneumocephalus, and septic meningo-encephalitis because of a cribriform plate defect. Care must be taken to prevent rotation of bone grafts used in cribriform defect repair. 相似文献
48.
49.
Oral prophylactic medication with either procaine penicillin G or a mixture of chlortetracycline, sulphadimidine and procaine penicillin G reduced the incidence of streptococcal meningitis in a herd of pigs with a high recorded prevalence of the disease, but to a significant extent (P less than 0.01) only in those pigs receiving procaine penicillin G. Subsequent studies showed that after oral administration of procaine penicillin G, benzylpenicillin was detectable in plasma only at very low concentration and similar results were obtained using the potassium salt of penicillin G. However, phenoxymethyl penicillin administered orally provided high plasma concentrations of this drug. A further investigation demonstrated that despite the low plasma concentrations of penicillin after oral administration of the procaine salt, gastrointestinal and urinary concentrations of the drug were relatively high for up to five hours. 相似文献
50.
Laurie L. Head Gregory B. Daniel Timothy J. Becker David A. Lidbetter 《Veterinary radiology & ultrasound》2005,46(3):263-266
The normal feline pancreas has been evaluated using radiolabeled leukocytes (99mTc-HMPAO) and computed tomography. The purpose of this report is to describe a clinical case where both modalities were utilized to assess the inflamed feline pancreas. A nine year old female cat presented with anorexia, depression and some vomiting. Blood values were unremarkable. Radiographs and ultrasound were suggestive of pancreatitis. The cat's leukocytes were separated and labeled according to an established protocol. Whole body images were acquired immediately, at 5 and 30 min, and at 1, 2, 4, and 17 hours post injection. Approximately 48 h later, the animal was anesthetized and computed tomography of the abdomen was preformed both pre and post contrast. Surgical biopsies were taken. The distribution of the WBCs was similar to that documented in normal animals, however, at 2 h there was faint uptake seen in the region of the pancreas. This uptake became more intense at 4 h and persisted at 17 h. Computed tomography showed irregular margination of the pancreas, it was larger than normal and inhomogeneous. Contrast enhancement was inhomogeneous and its peak enhancement was not reached until 10 min post injection; normal feline pancreas enhances homogeneously and peaks immediately. Histopathology confirmed pancreatitis with lymphocytic, plasmacytic, neutrophilic and eosinophilic inflammation and fibrosis. Radiolabeled leukocytes can be used to document pancreatic inflammation and this is best seen 4 h after injection. Computed tomography allows superior visualization of the pancreas. Both the appearance and contrast enhancement pattern of the inflamed pancreas differ from normal. 相似文献