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71.
W M Kuzon Jr J D Rosenblatt B R Pynn P J Marchetti M J Plyley N H McKee 《Canadian journal of veterinary research》1989,53(2):125-132
The purpose of this study was to determine whether there were differences in skeletal muscle properties in the hindlimb muscles of different types of dogs. Muscle samples were obtained from the gracilis, sartorius cranial head, sartorius caudal head and tibialis anterior muscles of mixed-breed and hound-type dogs and Beagles. Fiber type, fiber size and capillary morphometry determinations of each muscle from each dog were made from sections stained for myofibrillar ATPase activity. Individual animals were bilaterally symmetric for all measured variables. Fiber type, fiber size and capillary geometry varied between dogs of a given type and muscles within a given dog. There were no differences between dog types for fiber type or fiber size; significant variation in log(muscle)/log(body) mass ratios between dog types was observed for all muscles. The results indicate that for a given muscle, significant variation can occur in skeletal muscle characteristics between different types of dogs and that these differences can be independent of differences in exercise history. 相似文献
72.
Oxidized copper wire, commonly referred to as copper oxide needles (CuON), was evaluated using purebred Hereford cows and their calves. Thirty-seven cows were allocated to Cu treatments of 0, 25 or 50 g CuON (79.9% Cu in CuON) with 12, 12 and 13 cows per treatment, respectively; calves within cow treatments were allocated to treatment of 0 and 20 g CuON. Single oral doses of CuON were given at the start of a grazing trial that lasted 92 d. Cows and calves were weighed and blood samples were taken on d 0, 28, 63 and 92; liver biopsies were taken on d 0, 28 and 92 of the grazing trial. Cattle were consuming grass forage with mean concentrations on d 0, 28, 63 and 92 of the grazing trial ranging from 1.6 to 5.5 mg/kg DM for Cu, 2.5 to 5.5 mg/kg DM for Mo and 1.3 to 1.5 g/kg DM for total S. The water consumed by cattle contained 947 mg sulfate per liter (SE = 13.2, n = 4). Body weight of cows and calves was not influenced (P greater than .05) by CuON. Liver Cu was higher (P less than .01) in treated cows and calves but was not different (P greater than .05) between cows dosed with 25 or 50 g CuON. Treatment of cows and calves with CuON had no influence (P greater than .05) on the concentration of Fe or Mo in liver or plasma, the concentration of Cu and ceruloplasmin activity in plasma, or the concentration of Zn in liver. Plasma Zn did not differ (P greater than .05) in cows, but it was higher (P less than .05) in the calves suckling cows treated with CuON. It was concluded that dosing cows and calves with CuON resulted in a higher Cu content of liver but did not adversely influence the metabolism of Fe or Zn or modify the concentration of Mo in the plasma or liver of cows or calves. 相似文献
73.
Fatal poxvirus infection in association with FIV infection 总被引:1,自引:0,他引:1
74.
Residual ovine nematode pasture infections were assessed by grazing groups of ewes and their lambs on permanent sheep and cattle pastures and by the use of tracer lambs. Ostertagia spp., Cooperia oncophora, Nematodirus spp., Chabertia ovina and Trichuris spp. eggs and/or larvae survived on pastures overwinter. Second generation Ostertagia larvae were present in greatest numbers on pasture during the latter part of August and early September. The failure of a significant build-up of Cooperia oncophora was attributed to negligible worm egg output of this species in sheep. A build-up of Nematodirus spp. on pasture was not detected in this study. 相似文献
75.
A total of 739 cattle from nine breeds maintained at the Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, Nebraska were tested for 42 class I antigens of the bovine major histocompatibility system (BoLA). Each antigen appears to be the product of a distinct co-dominant allele of the BoLA-A locus. The number of antigens present in each breed ranged from a minimum of 10 in Hereford to a maximum of 21 in Charolais cattle. There were large differences among breeds in the frequencies of antigens. The effect of each antigen on birth weight, preweaning weight gain and postweaning weight gain was estimated in a gene substitution model. Each breed was analyzed separately. There were significant effects of some BoLA antigens on birth weight, preweaning weight gain and postweaning weight gain, which is consistent with previous reports showing associations between the major histocompatibility system and growth parameters in mice, rats and pigs. However, further research is necessary to confirm these findings and to determine the biological mechanisms underlying these associations. 相似文献
76.
M.L. Castor BS R.E. Wooley DVM PhD E.B. Shotts PhD J. Brown DVM PhD J.B. Payeur DVM PhD 《Journal of Equine Veterinary Science》1989,9(5)
During an outbreak of equine salmonellosis in a veterinary teaching hospital 20 Salmonella isolates were cultured from sick horses (13 isolates) or from the hospital environment (7 isolates). Three serotypes were isolated from the environment including: S. give, S. newportand S. agona. The serotypes isolated from horses included: S. give, S. newport and S. anatum. Examination of antibiotic profiles, presence of plasmids, production of bacteriocins and hemagglutination of erythrocytes implied a common origin for the equine and environmental isolates. 相似文献
77.
N E Forsberg M A Ilian A Ali-Bar P R Cheeke N B Wehr 《Journal of animal science》1989,67(12):3313-3321
The objectives of this study were to examine effects of a beta-adrenergic agonist (cimaterol) on growth and muscle development in rabbits and to examine cimaterol's effects on myofibrillar protein degradation (MPD) and on activities of several proteolytic enzymes including the calcium-dependent proteinases (CDP). Twelve New Zealand White rabbits were assigned to either control diets or to diets containing cimaterol for 35 d, after which they were killed and effects on performance and tissue weight gains were determined. Urine was collected from d 21 through 28 from each rabbit for assessment of N tau-methylhistidine (NMH) excretion. Cimaterol increased rates of gain, efficiency of gain and skeletal muscle weights. Enhancement in muscle weight was associated with an increase in total DNA and with a reduction in NMH. Cimaterol did not affect activities of cathepsin B, cathepsin D or neutral serine proteinase, but it reduced activities of the millimolar and micromolar forms of the CDP by 58 and 57%, respectively, and it reduced activity of the inhibitor of the CDP (calpastatin) by 52%. Cimaterol-dependent myofibrillar protein accretion was likely mediated, at least in part, by a reduction in MPD. The change in MPD was associated with a reduction in muscle CDP activities. Cimaterol-dependent muscle hypertrophy therefore may involve changes in calcium-dependent proteolysis of myofibrillar proteins. The significance of the effects of cimaterol on calpastatin activity is not known. 相似文献
78.
The spontaneous EEG and somatosensory evoked potentials (SEPs) were examined in chickens before and after electrical stunning using a waterbath stunner. Fifty-four per cent of the birds became epileptic and lost their SEPs, and 17% were non-epileptic and appeared to retain their SEPs. It was concluded that there was a reasonably close association between the presence of epileptiform activity in the EEG and the absence of SEPs following electrical stunning, but that the absence of SEPs could be preferred as an indicator of an effective stun on conceptual grounds. 相似文献
79.
Effect of endocytic and metabolic inhibitors on the internalization and intracellular growth of Brucella abortus in Vero cells. 总被引:3,自引:0,他引:3
Uptake, transfer to rough endoplasmic reticulum, and intracellular growth of Brucella abortus were studied in Vero cells treated with endocytic and metabolic inhibitors. Infection of Vero cells was suppressed when inhibitors of energy metabolism (iodoacetate, dinitrophenol), receptor-mediated endocytosis (monodansylcadaverine, amantadine, methylamine), or endosomal acidification (chloroquine, ammonium chloride, monensin) were added to the inoculum. Inhibition was not observed when these drugs were added after the inoculation period. Infection of Vero cells by B abortus was inhibited by dibutyryl-cyclic adenosine monophosphate and Vibrio cholerae enterotoxin, but was stimulated by dibutyryl-cyclic guanosine monophosphate and escherichia coli heat-stable enterotoxin a. Uptake of B abortus by Vero cells was not prevented by colchicine, but was abolished by cytochalasin B. Uptake of heat-killed B abortus and noninvasive E coli was similar to that of viable brucellae. Intracellular growth of B abortus was not affected by cycloheximide. Results indicate that: B abortus may be internalized by a receptor-mediated phagocytic process; transfer of B abortus from phagosomes to rough endoplasmic reticulum may require endosomal acidification; and replication of B abortus within the rough endoplasmic reticulum may not depend on protein synthesis by the host cell. 相似文献
80.
A Comparison of Injectable Anesthetic Combinations in Horses 总被引:4,自引:0,他引:4
N. S. MATTHEWS DVM Diplomate ACVA S. M. HARTSFIELD DVM MS Diplomate ACVA J. L. CORNICK DVM MS J. D. WILLIAMS PhD A. BEASLEY AHT 《Veterinary surgery : VS》1991,20(4):268-273
Six combinations of injectable anesthetic agents were administered to six adult horses in a Latin square design. The drug combinations were xylazine-ketamine, xylazine-butorphanol-ketamine, xylazine-tiletamine-zolazepam, xylazine-butorphanol-tiletamine-zolazepam, detomidine-ketamine, and detomidine-butorphanol-ketamine. Measured variables were heart rate, respiratory rate, systolic blood pressure, arterial pH (pHa), PaCO2, PaO2, recumbency time, and number of attempts necessary to stand. Quality of induction and recovery, muscle relaxation, and response to stimulus were evaluated subjectively. The horses required significantly more attempts to stand after administration of xylazine-tiletamine-zolazepam, xylazine-butorphanol-tiletamine-zolazepam, and detomidine-ketamine than after xylazine-ketamine, xylazine-butorphanol-ketamine, or detomidine-butorphanol-ketamine. Mean recumbency times varied from 23.0 minutes with xylazine-ketamine to 41.3 minutes with xylazine-butorphanol-tiletamine-zolazepam. There were significant differences in mean heart rates at minute 15, mean respiratory rates at minutes 5, 10 and 15, and mean systolic blood pressures at minute 10 of anesthesia. There were no significant differences in pHa, PaCO2 or PaO2. 相似文献