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991.
992.
Valentine BA de Lahunta A Divers TJ Ducharme NG Orcutt RS 《Journal of the American Veterinary Medical Association》1999,215(11):1661-5, 1621
Two Belgian geldings, 4 and 14 years old, respectively, with muscle atrophy, weakness, and abnormal gait characteristic of severe advanced shivers were examined clinically and on necropsy. Neurologic examination revealed no evidence of ataxia, and the clinical diagnosis was neuromuscular weakness and shivers. Necropsies of both horses, including examination of pituitary, brain, spinal cord, spinal roots and ganglia, and peripheral nerves, revealed no gross or histologic abnormalities. Examination of multiple skeletal muscle specimens revealed chronic myopathic changes and periodic acid-Schiff positive, amylase-resistant inclusions within muscle fibers, characteristic of equine polysaccharide storage myopathy. It is suggested that underlying metabolic myopathy may be the cause of muscle weakness and cramping in horses with shivers. 相似文献
993.
994.
Van Hoogmoed L Rodger LD Spier SJ Gardner IA Yarbrough TB Snyder JR 《Journal of the American Veterinary Medical Association》1999,214(7):1032-1036
OBJECTIVE: To determine whether peritoneal fluid pH, glucose concentration, and lactate dehydrogenase activity can be used to differentiate horses with septic peritonitis from those with nonseptic peritonitis. DESIGN: Prospective study. ANIMALS: 46 horses, including 10 healthy horses, 15 horses with septic peritonitis, and 21 horses with nonseptic peritonitis. PROCEDURE: Peritoneal fluid and blood samples were analyzed for pH, glucose concentration, and lactate dehydrogenase activity. Complete blood cell counts were performed, and peritoneal fluid samples were submitted for bacterial culture. RESULTS: Horses with septic peritonitis had significantly lower peritoneal fluid pH and glucose concentrations than horses with nonseptic peritonitis and healthy horses. Compared with other tests, serum-to-peritoneal fluid glucose concentration differences > 50 mg/dl had the highest diagnostic use for detection of septic peritonitis. Peritoneal fluid pH < 7.3, glucose concentration < 30 mg/dl, and fibrinogen concentration > 200 mg/dl were also highly indicative of septic peritonitis. CLINICAL IMPLICATIONS: Peritoneal fluid pH and glucose concentration can be used to assist in the identification of horses with septic peritonitis. These measurements can provide an early indication of sepsis, especially if cytologic evaluation of peritoneal fluid is unavailable or results are equivocal and peritoneal fluid bacterial culture results are pending. 相似文献
995.
996.
Heath TJ 《Australian veterinary journal》1999,77(9):584-587
OBJECTIVE: To estimate the costs to the student of veterinary education. METHOD: A questionnaire was completed by 180 fourth-year veterinary students from the four veterinary schools in Australia. Frequencies and median costs were estimated using the SAS System for Windows 95. RESULTS: The median direct living costs were about $5000 per academic year, but were higher in Sydney and for those with additional expenses including children, pets and cars. Other costs associated with the course including text books, equipment and travel to practical work were of the order of $1000, and income foregone while doing practical work placed additional burdens on some. More than half the students from Sydney and Murdoch needed to work to provide basic necessities. Most of this work involved interaction with animals or people. The percentage of Queensland and Melbourne students needing to work was lower, 47 and 24 respectively, and fewer of those worked directly with animals or people. The students expected to repay a median of $14,000 after they graduate, with 70% of this being due to the Australian government as part of the Higher Education Contribution Scheme. CONCLUSIONS: Although parents contributed an average of between one-third and one half of the costs of obtaining a veterinary degree, the extent of parental contributions was very uneven and almost one half of all students needed to work to provide basic necessities. The average total debt on graduation was about half the annual starting salary, but those starting the course from 1997 are subject to much higher charges, and their average debt is likely to exceed one year's salary. 相似文献
997.
OBJECTIVE: To quantify stripping in traditional dipping operations and to revise dipping methods, based on prediction of stripping so that a more stable concentration of pesticide in the dipwash is achieved. DESIGN AND METHODS: Plunge and shower dips were operated sequentially according to traditional and revised dipping instructions. Dips were operated by continuous and intermittent replenishment. Samples of mixed dipwash were collected periodically and assayed for pesticide (diazinon) concentration. RESULTS: Diagrammatic representations of pesticide concentration versus number of sheep dipped indicated traditional dipping leads to wide variations in the concentration of pesticide in dipwash during dipping. Intermittent replenishment led to a 'saw-tooth' pattern in the pesticide concentration. Traditional continuous replenishment (using the starting concentration of pesticide) indicated both the rate and extent of stripping was higher in shower dipping. If sufficient sheep were dipped, equilibrium was reached between the rate of pesticide replenishment and removal. An alternative method of dip operation by continuous replenishment, using a low starting concentration of pesticide and a replenishment concentration high enough to offset the pesticide loss through stripping resulted in a more stable concentration of pesticide in the dip. CONCLUSION: Revision of dipping instructions can lead to exposure of sheep to stable concentrations of stripping pesticide during dipping. 相似文献
998.
999.
1000.
Relationship between skeletal muscle-specific calpain and tenderness of conditioned porcine longissimus muscle 总被引:8,自引:0,他引:8
Parr T Sensky PL Scothern GP Bardsley RG Buttery PJ Wood JD Warkup C 《Journal of animal science》1999,77(3):661-668
Tenderization of skeletal muscle in meat animals has been closely linked to the postmortem activity of the calpain proteolytic enzyme system, which includes the specific inhibitor calpastatin. Increased understanding of the skeletal muscle-specific calpain isoform p94 has prompted suggestions as to whether it too could have a role in the tenderization process. In this study, two groups of pigs were identified in which shear force measurements after 8 d of conditioning indicated a large variation in the tenderness of longissimus muscle. The quantity of p94 in the muscle was monitored by immunoblotting, using a porcine-specific polyclonal antibody raised against a recombinant peptide fragment generated as a fusion protein. The antiserum recognized a 94-kDa protein associated with myofibrils in skeletal but not cardiac muscle, as expected for this calpain isoform, although it could not be tested with the native protein because of the extreme instability of p94. In the first experiment, the mean shear force for the tough group was 6.71 +/- .28 kg (n = 12, SEM) and that of the tender group was 3.87 +/- .12 kg (n = 12), but there was no difference in the normalized absorbance of the immunopositive 94 kDa band on Western blots from samples collected at approximately 40 min postmortem. In the second experiment, the stability of p94 in chilled carcasses was investigated over 24 h, using a further two groups of 10 tough and 10 tender pigs of mean shear force values 5.36 +/- .14 kg and 2.81 +/- .15 kg, respectively. In tough and tender animals, there was a decline (P < .05) in the 94-kDa immunostaining material of mean half-lives of 13.8 and 12.9 h, respectively, although there was considerable variability. Despite this variability in half lives and shear force values, no correlation was seen between these factors. Thus, in porcine longissimus muscle, the variability in tenderness after 8 d of conditioning cannot be attributed to an underlying variability in p94. 相似文献