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951.
The effect of vitamin E and/or selenium deficiency on the kinetics of erythrocyte production and destruction has been investigated in swine. The plasma iron turnover rate, 59Fe incorporation into newly formed red cells as well as the 51Cr apparent red cell half-life, were not found to be significantly affected by either vitamin E deficiency, selenium deficiency or deficiency of both, as compared to replete animals. The results of this study suggest that vitamin E is not a limiting factor for normal erythropoiesis in young growing pigs. Erythropoiesis appeared, however, to be slightly decreased in selenium deficient pigs and will need to be further investigated.  相似文献   
952.
马立克氏病病毒致瘤基因meq功能研究的概述   总被引:4,自引:0,他引:4  
马立克氏病病毒 (Marek’sDiseaseVirus,MDV)之众多已得到鉴定的基因中 ,目前有 3个基因即 132 bpr、pp38、meq被认为可能与致瘤相关。其中 ,meq与 132 bpr两个基因是MDV 1所特有 ,已证实 132 bpr的拷贝数与毒株的致弱程度有关 ,pp38则被证实可抑制机体的免疫应答。meq基因由于具有与致瘤基因jun/ fos家族类似的分子结构 ,因此 ,我们有理由认为meq基因在MDV致病、致瘤中可能发挥重要的作用。本课题在国家自然科学基金和广西自然科学基金的资助下 ,历经 5年由三个单位共同攻关…  相似文献   
953.
Two previously identified single-nucleotide polymorphism markers located within the micromolar calcium-activated neutral protease gene (CAPN1) were evaluated for their association with variation in meat tenderness using one commercial sample of Simmental x Angus crossbred calves and one multibreed, crossbred research herd. The commercial sample included 362 animals sired by 23 registered Simmental bulls bred to unregistered Angus cows and represented current industry animals in which to test the predictive merit of the markers. The second sample was a research herd including 564 steers from the Germplasm Evaluation Cycle VII population at the U.S. Meat Animal Research Center, produced with semen from popular sires of the seven Bos taurus beef breeds with the most registrations in the United States (Angus, Charolais, Gelbvieh, Hereford, Limousin, Red Angus, and Simmental) on Angus, Hereford, and MARC III cows. These animals form a relatively outbred population that constituted a stringent test of the predictive merit of the genetic markers, although small groups were half-sibs. Warner-Bratzler shear force measurements were used to determine tenderness phenotypes for all animals. The populations were genotyped for two markers that predict variation at amino acid positions 316 and 530 of the mu-calpain polypeptide, produced by the CAPN1 gene. Minor allele frequencies for markers 316 and 530 in the commercial sample were 0.17 and 0.37, respectively, and in the Cycle VII animals, were 0.20 and 0.28, respectively. Both markers showed association with shear force in the commercial sample (P = 0.04) and the Cycle VII population (P = 0.02), supporting the hypothesis that they represent potential markers to aid selection for improved meat tenderness in commercial populations of beef cattle in the United States.  相似文献   
954.
The performance was compared of cows sired by Holstein, Jersey or Brown Swiss bulls out of Holstein-Friesian×Gir dams of 1/2 to 3/4 Holstein-Friesian content. The animals were kept in a single herd under the same management. The data were analysed by least-squares techniques under a model that included the fixed effects of breed of sire, Bos taurus fraction of the dam, parity, year and season of calving, and a random cow effect. Based on 480 observations, the milk yields per lactation for the Holstein, Jersey and Brown Swiss sired groups were 2821±163, 2320±61 and 2418±119 kg, respectively. The corresponding means for fat yield per lactation were 96.9±6.6, 86.8±2.5 and 92.8±4.8 kg; for protein yield per lactation were 85.3±5.1, 71.3±1.9 and 76.3±3.7 kg; for lactation length, 339±18, 283±7 and 313±14 days for fat percentage, 3.37±0.10, 3.73±0.04 and 3.77±0.07%; and for protein percentage, 3.02±0.05, 3.10±0.02 and 3.16±0.04%. The respective calving intervals were 487±24, 408±11 and 461±245 days. The yields of milk and protein per day of calving interval were similar in the Jersey and Holstein sired groups, while the former had higher yields of fat, implying that production economics might favour the smaller Jersey crosses in production systems in which the males were not reared. Crossing with Brown Swiss did not improve performance over the Holstein sired crosses.  相似文献   
955.
Two dogs were emaciated and hypoalbuminemic due to protein-losing enteropathy associated with a severe, focal, mucoid, cryptal ectasia of the duodenum and marked villus atrophy. In one case, diseased portions of the duodenum were obvious endoscopically and were limited to discrete, focal areas in the small intestine, with apparently more undiseased tissue than diseased tissue being present. The signs and lesions in one dog resolved after initiating combination dietary and pharmacological therapy.  相似文献   
956.
957.
958.
There are reports of horses with acute onset acquired cervical scoliosis and cutaneous analgesia. The underlying dorsal gray column myelitis that produces these neurologic signs has been only presumptively attributed to migration of Parelaphostrongylus tenuis within the spinal cord. Despite previous confirmation brain by polymerase chain reaction testing, of P. tenuis within the brain of horses by polymerase chain reaction testing, genetic testing has failed to definitively identify the presence of this parasite in cases of equine myelitis. This case report provides molecular confirmation via polymerase chain reaction of P. tenuis within the cervical spinal cord of a horse with scoliosis and cutaneous analgesia.  相似文献   
959.
Mycophenolate mofetil (MMF) is recommended as an alternative/complementary immunosuppressant. Pharmacokinetic and dynamic effects of MMF are unknown in young‐aged dogs. We investigated the pharmacokinetics and pharmacodynamics of single oral dose MMF metabolite, mycophenolic acid (MPA), in healthy juvenile dogs purpose‐bred for the tripeptidyl peptidase 1 gene (TPP1) mutation. The dogs were heterozygous for the mutation (nonaffected carriers). Six dogs received 13 mg/kg oral MMF and two placebo. Pharmacokinetic parameters derived from plasma MPA were evaluated. Whole‐blood mitogen‐stimulated T‐cell proliferation was determined using a flow cytometric assay. Plasma MPA Cmax (mean ± SD, 9.33 ± 7.04 μg/ml) occurred at <1 hr. The AUC0–∞ (mean ± SD, 12.84±6.62 hr*μg/ml), MRTinf (mean ± SD, 11.09 ± 9.63 min), T1/2 (harmonic mean ± PseudoSD 5.50 ± 3.80 min), and k/d (mean ± SD, 0.002 ± 0.001 1/min). Significant differences could not be detected between % inhibition of proliferating CD5+ T lymphocytes at any time point (= .380). No relationship was observed between MPA concentration and % inhibition of proliferating CD5+ T lymphocytes (= .148, = .324). Pharmacodynamics do not support the use of MMF in juvenile dogs at the administered dose based on existing therapeutic targets.  相似文献   
960.
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