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41.
Pellets of three types of roughage were fed to veal calves, to determine their effect on the frequency of lesions (erosions or ulcers) of the abomasal mucosa. The number was increased in the calves fed roughage. Pellets produced from corn silage caused a greater number of lesions than pellets produced from barley straw or lucerne hay. It is concluded that the nature of the roughage plays a role in the pathogenesis of abomasal lesions. 相似文献
42.
Instructions on how to debone and stuff a turkey are available, but what is the best way to close it up? A randomised trial involving 15 turkeys was performed in order to evaluate skin disruption scores and cosmetic outcomes following the use of different suture patterns. Turkeys were deboned, stuffed and cooked according to guidelines of the US Department of Agriculture Food Safety and Inspection Services. After stuffing, they were randomly assigned to one of five closure groups: simple continuous Lembert; simple continuous Cushing; simple continuous Utrecht; simple continuous; or staples. Turkeys were cooked at 180 °C for two hours ensuring core temperature reached 75 °C. Suture line integrity was evaluated after removal of the sutures and the cosmetic aspect was graded. Before cooking, the Utrecht pattern and skin staples offered the best cosmetic result. After removal of the sutures, the skin remained intact only in the stapled group. All other suture patterns disrupted the skin after removal of the sutures, rendering the turkey less cosmetically appealing for serving. Closure of a stuffed turkey was best performed using skin staples to achieve the best cosmetic results. Using this technique you will be able to impress family and friends at a Christmas dinner, and finally show them your surgical skills. 相似文献
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Tryfonidou MA Holl MS Oosterlaken-Dijksterhuis MA Vastenburg M van den Brom WE Hazewinkel HA 《Domestic animal endocrinology》2003,25(2):155-174
The aim of the study was to investigate the influence of growth hormone (GH) on Vitamin D3 metabolism and the subsequent effects on calcium (Ca) homeostasis and skeletal growth in growing dogs. A group of Miniature Poodles received supraphysiological doses of GH (GH group; n = 6; 0.5 IU GH per kg body per day) from 12 to 21 weeks of age and was compared with a control placebo-treated group (n = 8). Biologic activity of GH in the GH compared to the control group was indicated by (a) the 2.5- to 3.5-fold increase in the plasma concentrations of insulin-like growth factor I (IGF-I), (b) the increased production of 1,25-dihydroxycholecalciferol as indicated by the significantly increased plasma 1,25-dihydroxycholecalciferol concentrations and the 12.9-fold increase in renal 1alpha-hydroxylase gene expression, and (c) the inhibited production of 24,25-dihydroxycholecalciferol as indicated by the significantly lower plasma 24,25-dihydroxycholecalciferol concentrations and the similar levels of renal 24-hydroxylase gene expression. Despite the distinct effects on Vitamin D(3) metabolism in the GH group, there were only moderate effects on the intestine, i.e. at 20 weeks of age there was a significant increase of 14.4 and 5.6% in fractional absorption of Ca and phosphate (Pi), respectively, compared to the control group. GH administration resulted in significantly elevated glomerular filtration rate, with no differences in Pi urine excretion as a result of a concomitant increase in the tubular reabsorption of Pi. GH had only limited disturbing effects on endochondral ossification as indicated by the maintenance of the regularity of the growth plates. However, GH had specific anabolic effects on bone formation without concomitant effect on bone resorption that may result in disorders of skeletal remodeling and manifestation of enostosis. 相似文献
48.
Rebel JM van Dam JT Zekarias B Balk FR Post J Flores Miñambres A ter Huurne AA 《British poultry science》2004,45(2):201-209
1. A study was conducted to investigate the effects of several vitamins and trace elements chickens and in chickens experimentally infected with malabsorption syndrome (MAS). 2. Vitamins and trace minerals in feed were varied. Breeders received either a basal amount of vitamins and trace minerals (low mix) or an increased amount (high mix). Their progeny also received either a low mix or a high mix. Effects of different breeder and broiler mix combinations on broiler performance, heamatology, spleen weight and humoral response were examined in control chickens. The effects of the different feeds and breeder, broiler combinations at the severity and recovery of MAS infection were also studied. 3. In general, the immune system can be stimulated by addition of vitamins and trace minerals, without affecting the growth potential of the controls. The number of leukocytes increased on d 1 in the broilers descended from breeders receiving high mix. The response to Newcastle disease virus boost was affected by the different amount of vitamins. 4. When breeders received a high mix the number of infiltrating polymorphonuclear leukocytes in the intestine was higher compared with breeders receiving basal amounts of minerals and vitamins. Also the recovery rate of intestinal lesions, cystic crypts of Lieberkühn and villus atrophy, as observed by histopathology, was faster in the groups where the breeders received high mix. 相似文献
49.
van Hoeij MJ Haarhuis JC Wierstra RF van Beukelen P 《Journal of veterinary medical education》2004,31(3):261-267
The cognitive level of short essay questions taken from assessments of two veterinary courses at the Faculty of Veterinary Medicine of Utrecht University (FVMU) was evaluated using a simplified classification tool based on the taxonomy of Bloom. Classifications were made by teaching staff members (subject matter experts, or SME) and by faculty members not involved in teaching the course (non-subject matter experts, or NSME). To compare the cognitive level assigned by raters in the SME group to that assigned by the NSME group, each test item was assigned a modal taxonomic level. The results indicate that the agreement level between a pair of raters within a group (SME or NSME) differed (34% to 77% and linear weighted Cohen's kappa coefficient 0.12 to 0.60). The agreement level on the modal taxonomic level between the SME and NSME groups for the two courses was 65% and 73%, with a linear weighted Cohen's kappa coefficient of 0.43 and 0.63 respectively. The requirement of expertise of a subject for classification is discussed. The introduction of the classification tool had a positive effect on teaching staff members' awareness of the importance of the cognitive level of assessments. Improvements to the classification tool to obtain higher agreement levels are proposed. 相似文献
50.
林荣杰 《国外畜牧学(猪与禽)》2010,30(6):17-19
养鸡的历史已有很长的时间,但是数十年前链式和盘式饲喂器的引入促进了许多有趣的发展。ChoreTime公司,即后来的比利时Roxell公司已经证明是新型饲喂器设计标准的革新者。 相似文献