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991.
Q. A. McKellar T. Pearson E. A. Galbraith J. Boyle G. Bell† 《The Journal of small animal practice》1991,32(2):53-58
The kinetics and efficacy of a cinchophen prednisolone combination preparation (PLT) were assessed in the dog. Cinchophen administered at a dose rate of 12-5 mg/kg intravenously had a volume of distribution (Vd area) of 0–13 litres/kg, a clearance rate (Cl) of 0–15 litres/h and a half-life (t 1/2β of 7–92 hours. Following oral administration the bioavailability was 87-21 per cent. Prednisolone administered at a dose rate of 0–15 mg/kg intravenously had a Vd area of 2–7 litres/kg, a CI of 0–116 litres/h and a t1/2β of 1–11 hours. PLT given to dogs with osteoarthritis at a dosage range of between 25 and 44 mg/kg per day cinchophen and between 0–125 and 0–220 mg/kg per day prednisolone for a maximum of 14 days significantly improved lameness (P<0–001), weight bearing (P<0–005), joint mobility (P<0–01) and stiffness (P<0–001) scores and was similar in clinical efficacy to phenylbutazone. 相似文献
992.
Congenital aortic stenosis was diagnosed in six cats. Clinical findings included dyspnoea, systolic murmurs with maximal intensity at the left apex or right sternal border, and cardiomegaly with congestive heart failure. Some clinical features of feline aortic stenosis were similar to those observed in cats with hypertrophic cardiomyopathy. Definitive diagnosis was obtained by angiographic imaging of a discrete, consistent subvalvular obstruction, Doppler-echocardio-graphy, or by necropsy. Although, two of the cats were diagnosed at ages older than usually reported, the overall prognosis for cats with aortic stenosis was poor. Four of the six cats died or were euthanased within one year of the onset of clinical signs. 相似文献
993.
The purpose of this study was to investigate the interaction between Escherichia coli and primary mammary epithelial cell cultures derived from cows with persistent intramammary infection (IMI). Two strains of E. coli, isolated from the milk of two different cows suffering from persistent E. coli IMI were tested for adhesion to and invasion of three primary mammary epithelial cell cultures derived from mammary biopsies of the two infected cows. Intracellular E. coli were detected during five days post infection in vitro. Both strains of E. coli adhered to and invaded monolayers of all three primary mammary epithelial cell cultures. One strain adhered less but invaded more than the other. Comparison with other mammary pathogens indicated that E. coli invaded the cells less efficiently than Staphylococcus aureus, about as efficiently as Streptococcus dysgalactiae and more efficiently than Streptococcus uberis. The mechanism of E. coli invasion was studied using the cytoskeleton disrupting agents colchicine and cytochalasin D. These compounds inhibited the invasion of E. coli. Invasion of E. coli could also be inhibited by the phosphokinase inhibitors genistein and staurosporin in a dose-dependent fashion. Phorbol-myristyl-acetate (PMA) had no effect on the invasion of E. coli. Histology of mammary tissue revealed chronic inflammatory changes in quarters that were persistently infected by E. coli. Intracellular bacteria were not detected in mammary tissue sections. Polymerase chain reaction (PCR) analysis suggested that the two strains of E. coli lacked genes encoding for bundle-forming pili (bfpA), intimin (eae) and translocated intimin receptor (tir), which are characteristic for enteropathogenic E. coli (EPEC). 相似文献
994.
995.
Kamphues J Zentek J Oberthür RC Flachowsky G Coenen M 《DTW. Deutsche tier?rztliche Wochenschrift》2001,108(7):283-290
The occurrence of BSE cases in Germany after the ban of meat and bone meal for ruminant feed in 1994 requires a detailed investigation of animal derived feedstuffs regarding their specific risks as vectors for the disease. Accepting the theory that BSE is a prion transmitted disease, the theoretical infectious potential was calculated for animal derived feedstuffs. This calculation was based on the assumption, that risk material (brain, spinal cord) of one clinically diseased cattle was rendered in the process as established in Germany (133 degrees C, 3 bar, 20 min) or, alternatively, that one diseased animal was slaughtered resulting in normal processing of the by-products for human food production. From this risk assessment it became obvious that meat and bone meal was one, but probably not the most important source for the spreading of BSE. Taking into account the high sensitivity of calves it can be speculated that certain products, e.g. from bone processing (bone meal) and fat melting (mixed animal fats), commonly used for the formulation of milk replacers, might have been more important as pathways. As it can't be excluded retrospectively that infected meat and bone meal was imported from the UK, this non-calculable influence may have been related to the significance of the other products. The calculation model underlines that efficient removal of specified risk material (brain, spinal cord) and adequate processing (133 degrees C, 3 bar, 20 min) or alternatively other equivalent treatments of fats are prerequisites for minimising the risk of feed borne transmission of BSE by animal derived feedstuffs. The epidemiological consequences are part of a subsequent paper. 相似文献
996.
Intensive longitudinal investigations of breeding and growing pig populations in two multiple-site swine production systems were conducted in NC, USA. Five cohorts of sows and individually identified growing pigs from their litters were serially sampled in order to determine the prevalence and serotypes of Salmonella enterica in each stage of production based on fecal culture. In addition to fecal samples, feed and environmental samples were obtained. Fifteen different serotypes were isolated from the two systems, the most frequently isolated serotypes were S. typhimurium var Mbandaka and S. typhimurium var Copenhagen. Pig prevalence estimates ranged from 0 to 48.1%. Environmental contamination was frequently encountered despite cleaning and disinfection. Feed was rarely (2/800, 0.25%) identified as S. enterica positive. We observed highly variable patterns of S. enterica prevalence and serotype profiles within cohorts over time and among cohorts within systems. These observations indicate that point estimates of S. enterica prevalence and serotypes cannot be considered as reliable indicators of the S. enterica status of farms, and that uncontrolled studies of interventions to control S. enterica may yield misleading results. These findings are critical to the design of epidemiological studies of S. enterica on swine farms and may suggest that cohort level, as opposed to farm or company level events or management practices, may be important as potential risk factors for S. enterica fecal shedding in market age pigs. 相似文献
997.
Sheehy JG Hellyer PW Sammonds GE Mama KR Powers BE Hendrickson DA Magnusson KR 《American journal of veterinary research》2001,62(9):1408-1412
OBJECTIVE: To evaluate mu-opioid receptors in synovial membranes of horses and determine whether these receptors are up-regulated in nerve endings during inflammation. SAMPLE POPULATION: Synovial tissue obtained from 39 client-owned horses during arthroscopy and 14 research horses during necropsy; brain and synovial tissues were obtained during necropsy from 1 horse, and control tissues were obtained from a mouse. PROCEDURE: Horses were classified into 7 groups on the basis of histologically determined degree of inflammation. Binding of primary rabbit antibody developed against mu-opioid receptors in equine synovial tissue was studied, using western blot analysis. Synovial membranes were tested for mu-opioid receptors by immunohistochemical staining, using a diaminobenzidine-cobalt chloride chromogen. Homogenates of synovial membranes were evaluated by use of radioligand binding. RESULTS: Examination of western blots of equine thalamus revealed that rabbit antibody developed against mu-opioid receptors yielded a band (molecular weight, 55 kd) that corresponded with that of other opioid receptors. Use of immunohistochemical staining of synovial tissue revealed considerable staining in the proliferative lining layer and in regions surrounding vascular structures. Specific radioligand binding of tissue homogenates was found in all groups. We did not detect significant differences in binding between horses with inflammation and horses without inflammation. CONCLUSIONS AND CLINICAL RELEVANCE: Results of immunohistochemical analysis and radioligand binding of tissue homogenates suggest that there are opioid receptors in synovial membranes of horses. Our results support the practice of intra-articular administration of opioids to relieve pain after arthroscopic surgery in horses. 相似文献
998.
J R Jenkins 《Veterinary Clinics of North America: Exotic Animal Practice》2001,4(3):651-667
Feather-picking and self-mutilation behaviors are common in psittacine birds. These behaviors are best defined as stereotypic behaviors or obsessive compulsive disorders. There is likely a genetic predisposition for these behaviors as reflected in the overrepresentation of a number of species of psittacines. Stereotypies most often result from a high level of arousal and the inability to respond with the appropriate natural behaviors. More specifically, conflict may be induced by the absence of releasing stimuli or target objects. On a chemical level, stereotypic behavior appears to be related to an increased dopaminergic activity and an increased dopamine turnover. Feather-picking and self-mutilation patients are challenging to treat and are most likely to respond to treatment at an early stage of development. The best results are obtained by identifying and removing the cause of conflict, enhancing the environment, using appropriate drugs when indicated, and employing counter-conditioning. 相似文献
999.
OBJECTIVE: To examine the effects of an aerosolized beta2-adrenoreceptor agonist, albuterol, on performance during a standardized incremental exercise test in clinically normal horses. ANIMALS: 8 Standardbred pacing mares. PROCEDURE: Clinically normal horses, as judged by use of physical examination, hematologic findings, serum biochemical analysis, and airway endoscopy, were randomly assigned to 2 groups and were given 900 microg of albuterol via a metered-dose inhaler 30 minutes before beginning a standardized incremental exercise test in a crossover design with a 7-day minimum washout. Further examination included measurement of baseline lung mechanics, response to histamine bronchoprovocation, and bronchoalveolar lavage. RESULTS: No significant differences (albuterol vs placebo) were seen for any incremental exercise test variables (ie, maximum oxygen consumption, maximum carbon dioxide consumption, respiratory quotient, treadmill speed at heart rate of 200 beats/min, or number of steps completed during an incremental exercise protocol). Mast cell percentage was significantly (r = -0.84) associated with the concentration of aerosolized histamine that evoked a 100% increase in total respiratory system resistance. No other direct correlations between bronchoalveolar lavage fluid cell types and any indices of exercise capacity or airway reactivity were found. CONCLUSIONS AND CLINICAL RELEVANCE: Although no horse had exercise intolerance, 4 horses had airway hyperreactivity with bronchoalveolar lavage fluid mastocytosis; these horses may have been subclinically affected with inflammatory airway disease. In our study, albuterol did not enhance performance in 8 clinically normal racing-fit Standardbreds. 相似文献
1000.
The aim of the study was to evaluate the occurrence of mycotic and protohecal mastitis in herds in south-eastern part of Poland. A total of 3091 milk samples from udder quarters with clinical and subclinical mastitis from 29 dairy herds was investigated in this survey. Milk samples were plated as soon as possible on blood agar (BA), Mac Conkey agar, aesculin-tallium acetate-crystal violet agar, and Sabouraud agar. A hundred and thirty one yeast (4.23%) and eleven Protoheca zopfii (0.35%) strains were isolated from cows with clinical and subclinical mastitis. All the isolated fungi were the yeast classified into 4 genera (Candida, Trichosporon, Saccharomyces and Rhodotorula). The most frequently isolated yeasts were Candida sp., C. kefyr, C. humicola, C. rugosa and C. inconspicua. Both fungi and algae were isolated first of all during a confinement-housing season. 相似文献