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11.
在日粮中添加 1 g· kg- 1 全蚕粉对鹌鹑的试验结果表明 :1饲喂 1 0、1 5、2 1 d后 ,体重分别增加 5 .0 0 %、6.67%和 1 1 .1 2 % ;2饲喂 2 1 d后 ,试验组料重比低于对照组 ;3血清总蛋白、白蛋白含量分别降低 1 2 .76%和 2 0 .84% ,血清葡萄糖、总胆固醇含量及白蛋白 /总蛋白比值差异不显著 ,但血清α-氨基氮含量试验组提高 1 8.84% ;4小肠粘膜麦芽糖酶和蔗糖酶活力分别下降 2 8.5 0 %和 3 8.67% ;5 T淋巴细胞转化率试验组比对照组高 2 0 .87% ;6血清胰岛素样生长因子含量提高 1 2 .1 4% ,生长激素和甲状腺素 T4水平分别提高 3 0 .0 8%和 2 0 .81 % ,T3差异不显著  相似文献   
12.
激素对蝴蝶兰快速繁殖的影响   总被引:9,自引:0,他引:9  
将蝴蝶兰原球茎在培养期间置于MS附加 6 BA ,NAA ,IBA ,2 .4 D等激素的培养基 ,诱导分化、增殖。结果表明 ,无菌母株在MS附加高浓度 6 BA(5 .0mg·L-1)和NAA(2 .5mg·L-1)条件下培养 2 5~ 30d后 ,转接到单独使用 6 BA(2 .0mg·L-1)的培养基中 ,并继代 2~ 3次 ,可连续不断地分化、增殖原球茎 ;若 6 BA浓度继续下调并与适当浓度NAA相配合 ,则有利于原球茎生长 ;低浓度 6 BA与IBA配合使用有利于分化苗生根。  相似文献   
13.
将225羽130日龄罗曼蛋鸡,随机均分5组,组5为对照。用4种中药方剂分别添加饲喂各组鸡群,直至对照鸡群产蛋率达90%左右。分别观察备组鸡群50%产蛋日龄、50%产蛋日龄前和用药期各组平均产蛋率、平均日蛋重、平均枚蛋重、料蛋比等生产性能指标。同时,在试验开始和结束当天(158日龄),各组随机采血12羽,测定血清雌二醇(E2)、胰高血糖素(Glu)、甲状腺素(T4)和三碘甲腺原氨酸(T3)及超氧化物歧化酶(SOD)、内二醛(MDA)含量和血清抗IBDV抗体水平。结果表明:以调整气血为主的中药方剂鸡群50%产蛋日龄比对照组5鸡群提前,且用药期有相对更高的平均产蛋率、平均日蛋重和更低的料蛋比、破蛋率,以及更高的血清E2、T3水平和SOD活性,更低的血清T4、MDA含量。对于产蛋初期蛋鸡,以调整气血为主要原则组方,对机体的免疫一内分泌系统和抗氧化功能有一定的促进作用,从而提高蛋鸡生产性能。  相似文献   
14.
分娩母猪母性行为的好坏直接影响到仔猪的成活率,尤其是一些母性行为失常的母猪直接咬死、踩死、压死仔猪,给养猪业造成巨大的经济损失。母猪分娩是受多种因素如神经、内分泌和胎儿等多方面影响和调控的一个复杂过程。近几年,虽然许多专家对分娩的机理进行研究,但到目前为止对造成母猪母性行为失常原因及机理的了解还不是很清楚。就分娩环境、机体内分泌、母猪遗传背景及产仔经验等影响分娩母猪母性行为的4个主要因素进行综述和讨论。  相似文献   
15.
作者观察分析了人工接种弓形虫强毒株后仔猪内分泌器官的动态病理组织学变化。各器官病变的主要发展过程为由充血、淋巴循环障碍到血栓形成,组织内嗜酸性粒细胞、嗜中性粒细胞和淋巴细胞浸润,最后组织发生严重水肿和坏死。垂体还可见小胶质细胞结节和坏死灶。胰腺和睾丸等内分泌部的损伤与恢复迟于外分泌部。  相似文献   
16.
The surgical success of laparoscopic castration without orchidectomy results from avascular necrosis of the testes. However, failures and subsequent production of testosterone and stallion‐like behaviour have been previously identified. Laparoscopic castration without removal of the testes was performed in 32 horses with 2 normal descended scrotal testes between July 2006 and October 2012. The objectives of our study were to evaluate the success rate of laparoscopic castration without orchidectomy on descended testes in our population and assess complications and recovery time. Endocrine tests were performed after surgery and owners also asked to report on their horse's behaviour and ability to resume exercise. Castration was deemed successful if endocrine test results were in accordance with gelding values. Failed horses were castrated using a conventional technique and histology performed when possible. Basal testosterone levels decreased below 3 nmol/l after surgery in 30/32 cases. However, in 2 horses, stallion behaviour persisted and histological evaluation after inguinal castration showed residual viable tissue. Two horses maintained high testosterone levels after surgery associated with stallion‐like behaviour. Based on these results, 12.5% of horses (4/32 horses) failed to be considered a gelding based on either endocrine tests and/or histology. All horses, with one exception, were able to resume exercise less than a week after the procedure. Laparoscopic castration without orchidectomy appears to be a safe procedure. When assessing the success of laparoscopic castration, our total failure rate was 12.5% (4/32 horses) which is significantly higher than previously reported.  相似文献   
17.
The presence of intestinal helminths in the alimentary canal of brown trout, Salmo trutta L., can alter the number of cells that synthesize modulatory peptides. A total of 167 brown trout were collected from tributaries of the River Brenta (northern Italy), of which 119 (71.3%) specimens were infected with enteric helminths, 28 with the acanthocephalan Pomphorhynchus laevis Müller, 1776 with intensity of infection ranging from 1 to 162 (18.57 +/- 30.79) worms per host and 67 fish with the cestode Cyathocephalus truncatus Pallas, 1781. Intensity of infection with C. truncatus ranged from 1 to 85 (6.87 +/- 12.59) per fish. In 24 fish there were concurrent infections of both species of helminths. The caecal and middle regions of the intestine were the most heavily parasitized. Immunohistochemical tests showed a decrease in endocrine cells (ECs) of the diffuse endocrine system (DES) positive to gastrin, cholecystokinin-8, bombesin and secretin antisera in the intestine of the infected trout. The number of ECs immunoreactive to anti-glucagon serum did not show differences in the digestive tract of uninfected brown trout and in conspecifics parasitized with P. laevis. The density of cells containing glucagon-like material was low in the fish parasitized with C. truncatus. The results suggest that endoparasitic helminths induce alterations in the DES of infected S. trutta.  相似文献   
18.
The annual reproductive cycle of walleye (Stizostedion vitreum) was characterized by documenting changes in gonadal development and serum levels of estradiol-17β (E2), testosterone (T), 17α,20β-dihydroxy-4-pregnen-3-one (17,20-P), and 11-ketotestosterone (11-KT) in wild fish captured from upper midwestern lakes and rivers throughout the year. Fish from the populations used in this study spawn annually in early- to mid-April. Walleye showed group synchronous ovarian development with exogenous vitellogenesis beginning in autumn. Oocyte diameters increased rapidly from ∼ 200 μm in October to ∼ 1,000 μm in November, and reached a maximum of 1,500 μm just prior to spawning. Changes in gonadosomatic indices (GSIs) paralleled changes in oocyte diameters. Serum E2 levels in females increased rapidly from low values in October (< 0.1 ng ml−1) to peak levels of 3.7 ng ml−1 in November, coinciding with the period of the most rapid ovarian growth. Subsequently, E2 levels decreased from December through spawning. Serum T levels exhibited a bimodal pattern, increasing to 1.6 ng ml−1 in November, and peaking again at 3.3 ng ml−1 just prior to spawning. We detected 11-KT in the serum of some females at concentrations up to 5.6 ng ml−1, but no seasonal pattern was apparent. In this study (unlike our results in a related study) 17,20-P was not detected. In males, differentiation of spermatogonia began in late August, and by January the testes were filled (> 95% of germ cells) with spermatozoa. Mature spermatozoa could be expressed from males from January through April. GSIs ranged from 0.2% (post-spawn) to 3.2% (pre-spawn). Serum T levels rose from undetectable levels in post-spawn males to 1.6 ng ml−1 by November, remained elevated throughout the winter, and peaked at 2.8 ng ml−1 I prior to spawning. Levels of 11-KT in males remained low (< 10 ng ml−1, from post-spawning through January, then increased significantly by March and peaked just prior to spawning at 39.7 ng ml−1. Our results indicate that vitellogenesis and spermatogenesis are complete or nearly so, in walleye by early winter, and suggest that it may be possible to induce spawning in this species several months prior to the normal spawning season by subjecting fish to relatively simple environmental and hormonal treatments.  相似文献   
19.
越来越多的环境内分泌干扰物( EDCs)不断释放到环境,并通过大气沉降、地表径流、土壤淋溶和直接排放等方式进入水体,从而使水体成为 EDCs 存在的主要场所之一。为引起社会对水体 EDCs 污染的广泛关注,并积极采取EDCs 危害防治措施,保护鱼类资源和水生态系统,本文介绍了 EDCs 的分类,详述了自然水体、饮用水源水以及自来水中EDCs 污染情况,阐明了 EDCs 对鱼类的生殖危害。资料分析显示,EDCs 能够扰乱生物体内分泌功能,导致生殖器官、生殖机能和生殖行为异常,引起生育力下降,甚至生物繁殖机能损害,并最终导致种群数量下降,以至物种灭绝。虽然国内外已经开展了一些关于 EDCs 对生物危害等方面的研究,但大都处于起步阶段,存在着基础研究薄弱、识别和鉴定困难或代价太大等问题,有关工作亟需全面、深入开展。  相似文献   
20.
比格犬神经垂体存在内分泌样细胞   总被引:1,自引:0,他引:1  
透射电镜观察表明,比格犬(Beagle)神经垂体内除含大量的无髓神经纤维、神经纤维膨体(赫令小体)、神经胶质细胞和血窦外,还可分辨出少量的肥大细胞和内分泌样细胞。内分泌样细胞的主要特征是:胞质内含有大量高电子密度的小分泌颗粒,颗粒呈圆形,表面有膜包裹,直径约109—213nm,主要分布于一侧胞质内。  相似文献   
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