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991.
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The hemorrhagic tendencies of 23 Doberman Pinscher pups were observed during cosmetic otoplasty and were ranked by a +1 to +4 grading system (+1 = least hemorrhage, and +4 = most hemorrhage). A second estimate of the hemostatic competencies of these dogs was made by counting the gauze sponges used in the otoplasties. Factor VIII-related antigen concentrations and coagglutinin cofactor concentrations were measured in plasma samples from blood drawn not more than 30 hours before the surgical procedures were done. The factor VIII-related antigen concentrations were between 9% and 147% of the concentration in a normal plasma pool, and the coagglutinin cofactor concentrations were between 1% and 165%, indicating that some of these dogs had von Willebrand's disease. The hemorrhagic tendencies of 12 pups were graded +1. This group had a mean antigen concentration of 75% (min-max, 38% to 147%) and a mean coagglutinin cofactor concentration of 89% (min-max, 42% to 165%). These were significantly greater than the antigen and cofactor concentrations of the grades +2 (n = 5), +3 (n = 3), or +4 (n = 3) dogs. Significant differences were not found when antigen concentrations of the grade +2 dogs (mean, 16%; min-max, 11% to 22%), grade +3 dogs (mean, 13%; 12% to 16%), and grade +4 dogs (mean, 11%; 9% to 12%) were compared with each other, nor were significant differences seen among the coagglutinin cofactor concentrations of the grade +2 dogs (mean, 7%; min-max, 1% to 11%), grade +3 dogs (mean, 6%, 4% to 8%), and grade +4 dogs (mean, 5%; 2% to 9%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
995.
After a 45-hour infusion of 15N-lysine and 15N-glycine resp. with pigs of 25 kg live weight, the infusion of the tracer was disrupted and a 3-day reduction phase was made part of the experiment. The N-metabolism parameters such as protein synthesis and decomposition quotas were calculated on the basis of the temporal development of 15N-amounts excreted in urine. The labelling and reduction phases were evaluated simultaneously. By means of including the total N-amount of the animal body the balance calculation becomes more stable. The possible influence of the tracer amino acid in connection with the 3-pool-model is discussed on the basis of the ascertained parameters.  相似文献   
996.
Sixteen 10-wk-old, phosphorus (P)-depleted Holstein bull calves were fed for 6 wk a control diet containing .08% P or P-supplemented diets containing .14, .20 or .32% P with supplemental P from two sources (CDP and Dynafos). The diets contained .45, .56, .66 and .87% Ca. After 5 wk of the experiment, the calves were dosed orally with 65Zn, and daily total fecal collections were initiated. At the end of the experimental period, the calves were killed and tissue samples were taken for total Zn and 65Zn analyses. Growth, feed intake and feed efficiency improved with increasing dietary P levels. Level of dietary P and Ca had little or no effect (P greater than .05) on total Zn content of rib, tibia, liver, heart, kidney, muscle or blood. Likewise, 65Zn absorption and content in most tissues were not affected (P greater than .05). The results do not preclude the possibility of some minor effects of P levels on Zn metabolism. However, it is apparent that when adequate Zn is fed, any effects are likely to be of little or no practical importance.  相似文献   
997.
998.
Shaky-leg lameness is a poorly defined, mild to very severe, painful lameness occurring mainly in 10-to-18-week-old fast-growing male turkeys. Since there are no significant gross or microscopic lesions in early or uncomplicated cases, the cause of the lameness is likely soft-tissue (muscle or tendon) pain. A case history of a flock problem of shaky-leg lameness is described, and it is suggested that stiffness and inactivity secondary to footpad dermatitis in these turkeys was responsible for the severe shaky-leg lameness in the flock. The cartilage lesion described is an avascular lesion and appeared to be the result of inactivity rather than the cause of lameness in these turkeys.  相似文献   
999.
The pathogenesis of canine parvovirus-2 was studied in orally inoculated conventional dogs using histopathological and peroxidase anti-peroxidase staining techniques. Lymphoid necrosis and depletion of lymphocytes from lymphoid tissues were most notable on days 5 and 6 after exposure. Lymphocyte hyperplasia occurred following day 7. Epithelial cell changes in segments of the small intestine were more severe on days 6 to 9 after exposure in areas associated with Peyer's patches and in the upper segments of the small intestine. The lymphocyte was the primary infected cell. Virus infected cryptal epithelial cells were not detected until 24 hours after the identification of infected cells in lymphoid tissues on day 4 after exposure. The majority of virus infected epithelial cells were found in crypts intimately associated with or adjacent to Peyer's patches in the upper segments of the small intestine.  相似文献   
1000.
A young African grey parrot was presented for necropsy following a 3-to-4-day illness consisting of lethargy, anorexia, and diarrhea. A disseminated necrotizing hepatopathy was evident upon histologic examination of the liver. Aggregates of approximately 70-nm-diameter viral particles having morphology consistent with the family Reoviridae were demonstrated by thin-section and negative-staining electron microscopy.  相似文献   
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