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971.
This study was designed to evaluate the ontogeny of serum IGF-I (SI) concentrations and its relationship to animal performance in a 140-d postweaning feeding trial. Ninety-eight progeny representing six sires (three high and three low feed conversion) and two sexes (43 bulls and 55 heifers) with ad libitum access to feed were allocated by sire and sex to monitor individual weights and pen feed consumption. Blood serum samples were obtained at the beginning of test (average age of 230 d) and every 28 d thereafter until each animal reached a fat thickness (estimated by sonoray) of 8.9 mm. Individual serum samples were acid-ethanol extracted and measured for IGF-I peptide by heterologous RIA. Serum IGF-I concentrations differed (P less than .10) between high (H) and low (L) feed conversion progeny groups at the end of the first 28-d period (125.12 vs 89.52 ng/ml) and tended to differ at the conclusion of the second 28-d period (P less than .15). Weight gains of H and L groups tended to differ in the second and third 28-d periods (P = .11 and .10, respectively). Serum IGF-I concentrations differed (P less than .05) between bulls and heifers for the first through fourth 28-d periods (P less than .01, P less than .05, P less than .10 and P less than .01, respectively). Phenotypic correlations indicated that pens with higher mean SI concentrations at the beginning of the test consumed less feed and had lower cumulative feed:gain ratios.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
972.
Prevention of large colon displacements and volvulus   总被引:1,自引:0,他引:1  
Results of these studies have demonstrated that colopexy of the left large colon to the abdominal wall is a relatively simple and quick procedure that is permanent 1 year after surgery. The technique does not appear to be associated with long-term weight loss or abdominal pain after surgery. It has been used in pregnant mares, both experimentally and clinically, without apparent complications. In addition, horses used for pleasure-riding and show hunting have returned to performance and have not had complications. Large colon resection is a useful technique, especially for animals with strangulating large intestinal lesions. The surgeon must decide whether a technique to prevent recurrence should be performed at the first surgery or whether it should be performed only in horses with recurrence of these lesions. Until a large number of large colon resections or colopexies are performed on horses either at the initial surgery or after recurrence, it is impossible to predict the true efficacy of these techniques.  相似文献   
973.
The effect of colostrum on endocrine and metabolic factors affecting glucose homeostasis was evaluated in 60 neonatal pigs that were fasted, fed (nursed ad libitum) or limit-fed colostrum (25% ad libitum, 4-hr interval feeding). Plasma acquired at birth (t0), and after 10, 20 and 30 hr (t10, t20 and t30, respectively) was analyzed for glucose, non-esterified fatty acids (NEFA), and the glucoregulatory hormones--insulin, glucagon, cortisol, growth hormone and catecholamines. The concentration of glucose and NEFA was similar among treatment groups at birth and increased in proportion to the quantity of colostrum consumed. Pigs fed ad libitum achieved and maintained a higher (greater than or equal to 40%; P less than .01) glucose concentration when compared to fasted neonates. Limit-fed counterparts also achieved and maintained higher levels, with glucose concentration being approximately 20% higher throughout (P less than .05). Fed pigs maintained NEFA concentrations which were approximately 2.5-fold to 4-fold greater than that of fasted pigs (P less than .05). Likewise, limit-fed pigs tended (P = .19) to have elevated NEFA concentrations and a lower (P less than .05) insulin:glucagon molar ratio. An inverse relationship was observed between colostrum intake and plasma concentrations of cortisol and growth hormone. Concentrations of epinephrine and norepinephrine tended (P greater than .10) to be elevated in fed pigs, relative to those of fasted counterparts. Provision of even limited quantities of colostrum is therefore beneficial to the glucoregulatory response in newborn pigs.  相似文献   
974.
OBJECTIVE: To determine risk factors associated with development of postoperative ileus in horses undergoing surgery for colic. DESIGN: Case-control study. ANIMALS: 69 horses that developed ileus after surgery for colic and 307 horses that did not develop postoperative ileus. PROCEDURE: Signalment, history, clinicopathologic data, treatment, lesions, and outcome were obtained from medical records. RESULTS: Variables associated with increased risk of postoperative ileus included age > 10 years, Arabian breed, PCV > or = 45%, high serum concentrations of protein and albumin, anesthesia > 2.5 hours' duration, surgery > 2 hours' duration, resection and anastomosis, and lesions in the small intestine. Enterotomy reduced the risk of postoperative ileus. After multivariate logistic regression, the final model included the variables Arabian breed, PCV > or = 45%, lesion type, duration of surgery (> 2 hours vs < or = 2 hours), and pelvic flexure enterotomy. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that by evaluating certain factors, horses at increased risk of postoperative ileus may be recognized before the condition develops. Preventative treatment and early intervention may be instituted in these horses. Shortening surgery time and performing an enterotomy may decrease the probability of horses developing postoperative ileus.  相似文献   
975.
976.
977.
978.
Two trials were conducted to determine the effects of breed type, backgrounding program, and backfat end point (USBFEP) as determined by ultrasound on the performance and carcass characteristics of feedlot steers. Trial 1 utilized 144 large-framed Charolais- (304.6 +/- 16.3 kg) and 144 medium-framed Hereford-cross steers (294.8 +/- 20.9 kg). Trial 2 utilized 88 medium-framed Angus (289.5 +/- 15.0 kg), 88 large-framed Charolais- (299.8 +/- 17.7 kg), and 88 medium-framed Hereford-cross (291.1 +/- 20.9 kg) steers. Within breed type, short- (70 d) or long-term (126 d) backgrounding programs (Trial 1) and 6- or 12-mm USBFEP (Trials 1 and 2) were assigned. In both trials, carcass size was greater (P < 0.05) for the large-framed Charolais-cross steers, longer backgrounding, and fatter USBFEP treatments. Lean meat yield was greater (P < 0.05) for Charolais- than Hereford-cross steers (Trial 1) and for the leaner USBFEP (Trials 1 and 2). Marbling was greater (P < 0.05) for Angus- (Trial 2) and Charolais- (Trials 1 and 2) than Hereford-cross steers (Trials 1 and 2) and for the fatter end point (Trials 1 and 2). It was concluded that breed type, backgrounding program, and USBFEP were effective in altering growth and could be used to target carcass traits of interest for value-based marketing programs.  相似文献   
979.
OBJECTIVE: To determine whether platelets obtained from cats expressed glycoprotein Ib (GPIb). SAMPLE POPULATION: Platelets obtained from 11 specific-pathogen-free cats. PROCEDURE: Platelets were analyzed by use of immunofluorescence microscopy, flow cytometry, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, western immunoblot analysis, and immunoprecipitation. RESULTS: Immunofluorescence microscopy and flow cytometry revealed the protein on the surface of feline platelets. Biochemical studies (western immunoblot analysis and immunoprecipitation) revealed a 140-kd membrane glycoprotein. Additional biochemical studies revealed that feline GPIb was sensitive to proteolysis, because platelet cytoskeletons prepared with low concentrations of a calpain inhibitor (ie, leupeptin; 100 microg/ml) had substantial proteolysis, and there was an association of protein fragments with the actin cytoskeleton. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of these results indicate that feline platelets express a 140-kd membrane protein that is recognized by monoclonal antibodies developed against GPIb. Application of standardized ELISA to quantitate glycocalicin, the water-soluble fragment of GPIb, may provide important information on the production of microvesicles, increased platelet turnover, and abnormal proteolysis.  相似文献   
980.
Typing of Salmonella enterica subsp. enterica serovar Mbandaka isolates   总被引:2,自引:0,他引:2  
Recently, Salmonella enterica subsp. enterica serovar Mbandaka (S. Mbandaka) has gained some importance in the epidemiology of salmonellosis in Poland. Since biotyping, resistance typing, and plasmid profiling were insufficient for strain differentiation, genome macrorestriction by means of pulse-field gel electrophoresis (PFGE) was applied and proved to be the method of choice in S. Mbandaka epidemiological studies. XbaI and BcuI macrorestriction produced 15 and 14 pulse-field profiles (PFP), respectively, but in the case of each enzyme one profile was prevalent. When macrorestriction profiles were combined, a total 24 patterns were found. Based on the similarity of the profiles, four clonal lineages were identified. One clonal lineage contained the majority of poultry, feed and human isolates. Poultry was concluded to be an important source of S. Mbandaka for humans in Poland. Complementary use of various typing techniques improved efficacy of epidemiological studies giving possibility to subdivide S. Mbandaka into 35 types and the index of discrimination reached 0.947.  相似文献   
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