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981.
982.
983.
Cytogenetic and histological studies were carried out on an intersex horse which was diagnosed clinically as a cryptorchid. Surgery confirmed the horse to be a bilateral abdominal cryptorchid and histological examination revealed ovarian tissue associated with the left epididymis. Chromosome analysis of cultured cells from testicular tissue, ovarian tissue and skin revealed 64-XX and 64-XY make-up, the left gonad containing a greater preponderance of XX cells over XY cells. The external characteristics and behaviour of the horse were indistinguishable from that of a "routine" cryptorchid. Other cases of equine intersexes are reviewed and theories for the discrepancies between genetic, gonadal and phenotypic sex are discussed.  相似文献   
984.
Digestibility trials were performed with laying hens receiving 3 types of rations containing equal proportions of the same dietary components. The percentage of high-protein wheat in these rations was 74%. Ration I was supplemented with 0.12% lysine while 0.06% lysine was added to ration II; ration III remained unsupplemented. The crude protein content of rations 1 to 3 was 16.1%, 16.5% and 16.6%, respectively. The corresponding lysine percentages were 0.66, 0.62 and 0.56. Studies were made to investigate the influence of different lysine levels on the rate of N excretion and various amino acid data. These studies were carried out during two successive laying periods. Only random differences between the data for urinary N excretion and N balances per kg liveweight were obtained in the two laying periods and for the different lysine levels. The true lysine digestibility was significantly lower in the poor-lysine ration as compared with the ration with 0.66% lysine. Moreover, the absorptive capacity for thio-amino acids is influenced by the lysine level of the ration. The proportion of lysine contained in faecal crude protein increased with the decreasing lysine content of the ration. Similarly, the total number of amino acids present in faecal crude protein increased with the declining supply of lysine. These findings suggest that relatively more NPN compounds are excreted in the faeces if adequate amounts of amino acids are supplied rather than when one amino acid is deficient.  相似文献   
985.
Passive electrical values of 76 probes of pig M. long. dors. with different quality are derterminated. It appears, that a factor (P = value), exactly ascertained from electrical parameters, is fit to characterize the quality of pork. The P-value is theoretical established and has relations to the stability of the membrane structures.  相似文献   
986.
987.
988.
A preliminary field experiment was undertaken to evaluate the efficacy of alum precipitated toxoids of Sphaerophorus necrophorus prepared from sonicated whole cells and cell fractions to reduce the incidence of bovine abscesses. A total of 108 calves were divided into five groups and treated as follows: I. uninoculated control, II. adjuvant inoculated control, III. 15.5 mg protein of sonicated (fragmented cells) toxoid, IV. 10.5 mg protein of cytoplasmic toxoid. V. 15.5 mg protein of cytoplasmic toxoid. All animals were maintained under similar conditions to those prevailing in feedlots in Alberta. Livers were examined at slaughter. The most promising result was achieved with the injection of 15.5 mg protein of cytoplasmic toxoid. In this treatment group, no scars (healed lesions) were found in the liver and the incidence of liver abscesses was reduced to 10% from the average 35% liver abscesses and scars found in the uninoculated and adjuvant inoculated groups. The toxoid from sonicated whole cells did not reduce liver abscess incidence. These data suggest that the incidence of liver abscesses in cattle fattened in feedlots may be reduced by immunization.  相似文献   
989.
Torsion of a lung lobe in the dog   总被引:1,自引:0,他引:1  
A 3-year-old Whippet in severe respiratory distress was found to have an extensive pleural effusion associated with a 180o torsion of the cardiac lobe of the right lung. The possible cause of torsion and diagnostic indications of this lesion are discussed.  相似文献   
990.
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