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101.
为探索波尔山羊超排个体排卵数差异与个体遗传特性的相关性,对波尔山羊的FSHR基因(950 bp),分成四段分别设计引物进行PCR-SSCP多态性分析,结果发现一个SNP位点,导致5-’1出现两种基因型。序列分析显示该突变位点位于转录起始点上游-739bp处,属于远端转录启动调控区。统计分析表明AA型个体的平均排卵数与AB型个体的平均排卵数差异极显著(P<0.01),平均胚胎可利用率差异显著(P<0.05),这说明个体的超排潜力可能与其本身的FSHR基因的遗传特性有关。  相似文献   
102.
选用5只舍饲成年波尔山羊连续进行3昼夜行为习性观测,结果表明:试验羊昼夜采食222.4±34.2 min,反刍456.2±40.3 min,卧息480.9±25.0 min,自由活动220.5±38.8min,其它行为60.0±6.4min,反刍与采食时间比为2.1:1.0。反刍、卧息多发生在夜间(P<0.01),采食多发生在白天(P<0.01),白天与黑夜排粪、排尿时间差异不显著(P>0.05)。  相似文献   
103.
内蒙古荒漠草原优势牧草营养价值评价   总被引:3,自引:0,他引:3  
通过测定内蒙古荒漠草原26种优势牧草的常规养分含量、纤维组成、两极离体消化率,分析了不同牧草对放牧内蒙古白绒山羊的营养价值,同时应用随意采食量、静能估测模型计算了荒漠草原优势牧草的分级指数(GI值),对牧草进行了综合评价。结果表明:(1)用营养成分和消化率指标评定,紫花苜蓿和五星蒿的营养价值最高,其次为中间锦鸡儿、圆头藜,最次为驼绒藜;(2)紫花苜蓿、五星蒿、中间锦鸡儿、圆头藜、碱蓬、全叶马兰、蒺藜草、沙打旺、阿尔泰狗娃花9种牧草GI值较高,牛枝子、甘草、猪毛蒿、松叶猪毛菜、软毛虫实、小针茅居中,灰绿藜、冷蒿、中亚狼尾草、针茅、无芒隐子草、西藏锦鸡儿、驼绒藜、黑沙蒿、刺叶柄棘豆、芨芨草、差巴嘎蒿11种牧草的GI值较低。  相似文献   
104.
山羊痘病毒的分离鉴定及生物学特性的研究   总被引:6,自引:0,他引:6  
本研究对2003年广西部分地区山羊群发生的疑似山羊痘进行了病毒分离鉴定及生物特性的研究。取疑似山羊痘病羊的皮肤丘疹、水泡或脓泡组织的病毒悬液,接种初生羔羊睾丸细胞观察到明显的细胞病变,免疫荧光试验结果显示,病毒能与山羊痘标准阳性血清反应,在感染的细胞浆内发出特异性的黄绿色荧光。病毒悬液接种乳鼠、小鼠、豚鼠、兔子都未发病,而接种3月龄山羊则出现典型的山羊痘症状和病理变化,接种9~10日龄鸡胚绒毛尿囊膜,未见出现痘斑,连传3代,均无异常变化。通过病理组织学观察可以看到在细胞浆内有大小不一圆形或椭圆形的包涵体,在电子显微镜下可以观察到150nm~300nm大小,卵圆形、砖形,有囊膜的病毒颗粒。利用一对山羊痘病毒P32基因引物进行了PCR扩增,将所得序列与GenBank收录的5株山羊痘病毒P32基因的核苷酸及氨基酸序列比较分析。结果与疫苗株的同源性分别为99.8%和99.4%。与国外其它毒株的同源性为99.6%和98、8%~99.4%。研究结果表明,所分离的病毒为山羊痘病毒,在生物学特性上与资料记载存在一定的差异,P32基因与疫苗毒和国外毒株之间同源性非常高。将该毒株命名为山羊痘病毒LiuJiang/2003株。  相似文献   
105.
影响山羊胚胎冷冻效果因素的研究   总被引:4,自引:0,他引:4  
分别用浓度为1.5 mol/L的乙二醇(EG),1.5 mol/L 1,2-丙二醇(PROH)和1.5 mol/L甘油为冷冻保护液对山羊胚胎进行常规冷冻保存,结果三者对山羊胚胎的冷冻保护效果无显著差异,其中以1.5 mol/L EG的冷冻保护效果为佳。以EFS40为玻璃化液对山羊胚胎进行细管法和OPS法玻璃化冷冻,其结果与常规冷冻间差异不显著,表明常规冷冻法、玻璃化细管法和OPS法均可用于山羊胚胎的冷冻保存。采用25℃和37℃水浴对常规冷冻和玻璃化冷冻后的山羊胚胎进行解冻,从解冻后的发育效果看,二者间无显著差异,但37℃水浴解冻后的胚胎发育效果略好于25℃。还比较了玻璃化液EFS40中添加FCS和BSA后与不添加其他成分的EFS40对胚胎冷冻保护效果的影响,结果表明添加BSA的EFS40的冷冻保护效果显著地高于不添加其他成分的EFS40,但与添加FCS的EFS40间不存在统计学上的差异。  相似文献   
106.
激素对波尔山羊超排效果影响的研究   总被引:5,自引:0,他引:5  
以波尔山羊为研究对象,研究激素对供体超排效果的影响。结果表明,FSH剂量对供体超排效果有显著影响,随FSH剂量的增加,育成羊的黄体数极显著增多,经产羊的可用胚数显著增加;国产和进口激素对超排效果影响不显著(P>0.05),国产激素完全可以代替进口激素用于波尔山羊的超排;供体发情配种时用LHRH-A3促排的效果比LH、hCG好。  相似文献   
107.
The conjugated linoleic acid (CLA) content of grazing sheep and goat milk fat, throughout their lactation period, was examined. Six sheep and six goat representative farms were selected at random and milk samples were taken at monthly intervals for fatty acids profile determination. Sheep and goat nutrition was based on natural grazing and on supplementary feeding during the winter months. From April onwards, grazing native pastures was the only source of feed for sheep and goats. The University farm whose sheep are kept indoors all year round without any grazing, was also used as reference. Fifteen individual milk samples were also taken in April from a sheep and goat farm respectively, in order to see the variability of CLA inside the farm. The results showed that: a. the CLA content of grazing sheep and goat milk fat increased significantly in April–May (early growth stage of grass) and then declined while that of indoors kept sheep was more or less constant during the same period, b. the isomers cis-9, trans-11 and trans-10, cis-12 of CLA were found in grazing sheep milk fat, while in indoors kept sheep and goats' milk fat only the cis-9, trans-11 isomer was found, c. the CLA content of sheep milk fat was much higher than that of goats, d. a negative correlation between sheep milk fat and CLA content was found and e. there was considerable variation in milk fat CLA content between sheep and goat farms and inside the farms.  相似文献   
108.
In this study, we investigated the effect of ascorbic acid (AA) administration on goat excitability due to transportation. Ten goats administered AA (p.o.) at 100 mg/kg of body weight before transportation served as the experimental group, and seven goats administered only 10ml/kg of sterile water (p.o.) served as controls. Excitability scores were recorded for each goat; when weighed, before, immediately after, and 3 h after 8 h of transportation. A score of one to four was allocated to each goat; higher scores represent greater excitability. Immediately after transportation, excitability scores decreased significantly, especially those of control goats (p < 0.001). At 3 h post-transportation, the excitability scores of animals in the experimental group were not significantly (p>0.05) different from their pre-transportation normal values, whereas those of control goats were significantly lower (p < 0.01). The correlation i.e. the relationship between excitability score values and percent excitability (percentage of goat with particular excitability score) for different excitability score group 3 h post-transportation was positive and highly significant (p < 0.001), in both experimental and control goats. Our results indicate that road transportation induces considerable stress (depression) in goats as evidenced by a lower excitability score post-transportation. Moreover, the administration of AA pre-transportation facilitated the transition from a state of depression to excitation. In conclusion, AA administration to animals prior to transportation may ameliorate the depression often encountered after road transportation.  相似文献   
109.
In a previous study, it was found that there are sex differences in goats with respect to the levels of cortisol secretion induced by transportation stress. We also found that treatment of castrated male goats with dihydrotestosterone (DHT) suppressed the increase in plasma cortisol concentration following transportation, but did not suppress the secretion of adrenocorticotropic hormone (ACTH). This suggests that androgen might block ACTH ‐ induced cortisol secretion. In order to examine this hypothesis, the effects of androgen on ACTH‐induced cortisol secretion in goats were investigated. First, castrated male goats were treated with testosterone (T), DHT or cholesterol (cho) for 21–25 days. Cho was used as a control for T and DHT treatment. Then, plasma cortisol concentrations were compared among the hormonal treatments after ACTH injection. Subsequently, the distribution of androgen receptors in the caprine adrenal gland was investigated. There were no differences in the basal cortisol concentrations among the hormonal treatments. However, plasma cortisol concentrations after ACTH injection were significantly lower in T ‐ and DHT ‐ treated goats than in cho ‐ treated goats. Androgen receptors were present in 60% of the cells in the zonae fasciculata and reticularis of the adrenal cortex, the regions that secrete glucocorticoids. These results suggest that androgen may act directly on the adrenal cortex to suppress cortisol secretion induced by ACTH.  相似文献   
110.
比较了不同冷冻方法和冷冻保护液对山羊卵母细胞冷冻-解冻后体外受精和激活后的发育效果.结果表明,开放式拉长塑料细管(OPS)法的效果好于玻璃化细管法和常规冷冻法;在OPS法中,20%EG 20%DMSO对卵母细胞的冷冻保护效果好于EDFS40,而在玻璃化细管法冷冻中,则是EDFS40好于20%EG 20%DMSO.对于常规冷冻法而言,则是1.5mol/L EG的冷冻效果好于1.5mol/L PROH.  相似文献   
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