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11.
PA Accorsi N Govoni R Gaiani C Pezzi E Seren C Tamanini 《Reproduction in domestic animals》2005,40(3):217-223
Leptin may play a role in the endocrine-metabolic processes that guarantee the physiological course of lactation in dairy cattle. This study was aimed at determining the changes in plasma concentrations of leptin and some of the main hormones and metabolites involved in the lactogenetic process in high-yielding dairy cows throughout lactation; we also wanted to assess whether leptin secretion is subjected to seasonal influences. Blood samples were collected from 23 Italian Friesian dairy cows from the end of a lactation to the ninth month of the subsequent one; in addition, blood was sampled from 47 dairy cows in different phases of lactation during February and July. Plasma concentrations of leptin, growth hormone (GH), insulin, prolactin (PRL), glucose, non-esterified fatty acids (NEFA) and urea were quantified by either validated radioimmunoassay (RIA) or enzymatic colorimetric methods. At the beginning of lactation, GH concentrations significantly increased, while a significant reduction occurred in leptin and insulin. This endocrine condition, such as the significant increase in NEFA plasma concentrations, is indicative of a marked lipid mobilization. In the more advanced stages of lactation, when both energy and protein balances become positive, leptin plasma concentrations increased, whereas GH and NEFA concentrations declined. During the summer months, a significant increase in leptin plasma concentrations, irrespective of the phase of lactation, was observed. Collectively, our findings suggest that, in dairy cows, leptin may represent a 'metabolic signal' of animal's status of fattening and nutritional level; in addition, leptin seems to be influenced by photoperiod and environmental temperature. 相似文献
12.
Effects of interferents on the kinetic Jaffé reaction and an enzymatic colorimetric test for serum creatinine concentration determination in cats, cows, dogs and horses.
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R M Jacobs J H Lumsden J A Taylor E Grift 《Canadian journal of veterinary research》1991,55(2):150-154
The effects of acetoacetic acid, acetone, bilirubin, beta-carotene, three cephalospoprin antibiotics, glucose, hemoglobin and lipid on the kinetic Jaffé reaction and an enzymatic reaction for the determination of creatinine concentration were studied in bovine, canine, feline and equine serum. There were no obvious species' differences. The kinetic Jaffé reaction was unaffected by the addition of beta-carotene and hemoglobin. Acetone, cefazolin, cefoxitin, ceftiofur and glucose caused a positive bias while acetoacetic acid, bilirubin, and lipid caused a negative bias when added to the kinetic Jaffé reaction. The enzymatic reaction was unaffected by the addition of acetoacetic acid, acetone, beta-carotene, cefazolin, cefoxitin, glucose and hemoglobin while added lipid, bilirubin and ceftiofur caused a negative bias in the test results. Over all species and interferents, there was no difference in the precision of the two assay methods. In a series of sera from hospitalized patients, the two methods were highly correlated in a linear fashion. The enzymatic creatinine assay deals effectively with most interferents but has a greater cost and shorter shelf-life compared with the kinetic Jaffé reaction. 相似文献
13.
14.
Spherocytes were detected on blood smears of 2 Angus cows. The RBC from both cows had increased fragility in hypotonic saline solution, supporting the presence of spherocytes. Other laboratory tests revealed a macrocytic, regenerative anemia with anisocytosis, polychromasia, basophilic stippling, Howell-Jolly bodies, nucleated RBC, and Anaplasma marginale organisms. A complement-fixation test was positive for anaplasmosis in cow 1 and a direct Coombs' test was positive for immunoglobulin G in both cows. 相似文献
15.
16.
Jacobs G Calvert C Kraus M 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(1):96-99
Amiodarone is a class III antiarrhythmic drug used in dogs with dilated cardiomyopathy and ventricular tachyarrhythmias. Hepatopathy is one of the more commonly reported adverse effects of amiodarone use in people. We describe 4 dogs that developed hepatopathy associated with amiodarone administration; 2 dogs also developed neutropenia. Three dogs had clinical signs of anorexia and lethargy; 1 did not show signs until impaired liver function had developed. Clinical signs or biochemical abnormalities developed 1.5-8 months after amiodarone treatment was started. Clinical signs resolved within 2 weeks of discontinuing amiodarone, but biochemical abnormalities did not resolve for 6-8 weeks. The delay between onset of liver disease and overt clinical signs suggests that serial evaluation of liver enzyme activities following amiodarone use in does is important. 相似文献
17.
Nel LH Bingham J Jacobs JA Jaftha JB 《The Onderstepoort journal of veterinary research》1998,65(4):297-303
Antigenic and nucleotide sequence analyses have shown that two distinct biotypes of rabies virus are circulating in South Africa. One of these typically infects members of the family Canidae, while the other comprises a heterogeneous group of apparently indigenous viruses, infecting members of the Viverridae family. In recent times, it has become evident that a considerable amount of cross-infection may occur and the manifestation of viverrid rabies in non-viverrid animals in particular appears to have become more commonplace. Consequently, the need to rapidly distinguish between rabies virus biotypes has become increasingly important in efforts to monitor the epidemiology of rabies in the southern African region. In this study, a nested polymerase chain reaction (PCR) assay was developed to distinguish between these two groups of rabies viruses. Consensus oligonucleotides were used to amplify the cytoplasmic domain of the rabies virus glycoprotein and the adjacent intergenic region. The resultant amplicon was subsequently used as template in second round heminested PCR in the presence of type-specific primers, thereby successfully generating amplicons of characteristic size for each biotype. 相似文献
18.
Serum pancreatic polypeptide and amylase concentrations in dogs with experimentally induced acute pancreatitis 总被引:1,自引:0,他引:1
R J Murtaugh R M Jacobs R G Sherding T M O'Dorisio 《American journal of veterinary research》1985,46(3):654-656
Serum concentrations of immunoreactive pancreatic polypeptide (IPP) were measured serially for 7 days after experimental induction of acute hemorrhagic pancreatitis in dogs by infusion of oleic acid into the pancreatic duct. The mean serum IPP concentrations in dogs with pancreatitis were increased significantly (P = 0.013) for 96 hours after induction of pancreatitis. Providing food at 108 hours resulted in significant increases (P = 0.032) in mean serum IPP concentrations in sham-operated control dogs compared with dogs with induced pancreatitis. This was attributed to cephalic-phase release of IPP due to a conditioned response that resulted from feeding immediately after each blood sampling. Mean serum IPP concentrations returned to base line more quickly than did mean serum amylase concentrations in dogs with pancreatitis. 相似文献
19.
D. E. Jacobs M. A. Fisher J. G. Pilkington R. L. Jones V. C. Cracknell 《The Journal of small animal practice》1990,31(2):59-63
Trials were conducted to evaluate the anthelmintic effect of a combination of epsiprantel at a dose rate of 5-5 mg/kg bodyweight and pyrantel pamoate at 5 mg pyrantel base/kg against Toxocara canis in prenatally infected unweaned greyhound pups, Toxascaris leonina, Uncinaria stenocephala, Trichuris vulpis and Dipylidium caninum in naturally infected adolescent greyhounds and Ancylostoma caninum, U stenocephala. Taenia hydatigena and Taenia pisiformis in artificially infected laboratory beagles. The product was well accepted and produced no obvious side effects. Percentage efficacy values based on post mortem worm counts were: T hydatigena 100; T pisiformis 100; D caninum 100; adult T canis 84-0; adult T leonina 96-5; immature T leonina 99-8; U stenocephala 99-0 and 87-7; A caninum 92-7; and T vulpis 43-3. 相似文献
20.
In 7 horses, 4 anastomoses were done in the small intestine in each, using the combinations of synthetic absorbable monofilament and multifilament suture materials with continuous- and interrupted-suture patterns in the serosubmucosal layer of a 2-layer inverting-suture technique. Horses were evaluated 30 days after the operation for adhesion formation, lumen diameter, evidence of chronic obstruction, and suture tract inflammation at the anastomosis. Postoperative obstruction occurred in 5 of the 7 horses, and 6 horses survived. One horse was euthanatized on postoperative day 6 after 48 hours of ileus and obstruction; necropsy revealed a partial intussusception involving the anastomosis done with continuous multifilament-suture material. Two other horses that became obstructed between postoperative days 3 and 5 had protracted ileus and gastric reflux up to 48 hours' duration, but survived. Horses that had obstruction after the 6th postoperative day recovered within 4 hours of onset. The continuous inverting-suture pattern in the serosubmucosal layer resulted in significantly (P less than 0.05) fewer adhesions than did the interrupted pattern, and suture material had no effect on adhesion formation. There was no significant difference in the percentage of reduction of lumen diameter between the variations of the 2-layer technique, and there was no evidence of chronic obstruction related to any of the anastomoses. Suture tract inflammation was moderate in the anastomoses, using continuous-multifilament suture, with neutrophils being the predominant cell type. The anastomoses with continuous-monofilament suture had mild inflammation with focal accumulations of neutrophils. Minimal inflammation was associated with both types of suture in the interrupted pattern. 相似文献