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1.
采用自身对照法试验设计,将9只健康的卡拉库尔公羊分为3组,即对照组、试验组Ⅰ和试验组Ⅱ,研究在日粮中添加盐穗木对卡拉库尔羊瘤胃内环境的影响,结果显示:日粮中添加100 g盐穗木有降低卡拉库尔羊瘤胃液pH值和氨氮(NH3-N)含量的趋势,但盐穗木添加量为200 g时会提高瘤胃液pH值;添加100 g盐穗木可提高瘤胃中菌体蛋白含量,添加量为200 g时会降低菌体蛋白含量;日粮中添加盐穗木对卡拉库尔羊瘤胃液总挥发性脂肪酸(TVFA)含量无影响,有增大乙酸/丙酸比的趋势。  相似文献   
2.
A study was conducted to assess the combined effect of heat stress and nutritional restriction on growth and reproductive performances in Malpura rams. Twenty‐eight adult Malpura rams (average body weight (BW) 66.0 kg) were used in this study. The rams were divided into four groups: CON (n = 7; control), HES (n = 7; heat stress), NUS (n = 7; nutritional stress) and COS (n = 7; combined stress). The study was conducted for a period of 2 months. CON and HES rams had ad libitum access to their feed while NUS and COS rams were under restricted feed (30% intake of CON rams) to induce nutritional stress. The HES and COS rams were kept in climatic chamber at 42 °C and 55% relative humidity for 6 h a day between 10 : 00 h and 16 : 00 h to induce heat stress. Body weight increased significantly (p < 0.05) in CON as compared to NUS and COS. When compared within groups, scrotal width morning, scrotal width afternoon, scrotal circumference morning and scrotal circumference afternoon were significantly (p < 0.05) larger in CON while smaller in COS rams. The higher testicular length was recorded both during morning (p < 0.05) and afternoon (p < 0.01) in COS rams while the lowest in NUS rams. The highest plasma testosterone concentration was recorded in CON and lowest in COS rams. Semen volume and mass motility also differed significantly (p < 0.05) between the groups. The highest semen volume and mass motility was recorded in CON and NUS while lowest in both HES and COS rams. It can be concluded from this study that when two stressors occur simultaneously, they may have severe impact on reproductive performance of rams.  相似文献   
3.
指出了近年来随着城市的发展,人口和汽车数量不断增多,公共交通体系急需升级,轨道交通成为城市公交系统发展方向之一。以沈阳有轨电车项目为例进行了分析,根据典型路段预测了结果:在有轨电车最高运行时速情况下,距轨道中心线20m处,大部分路段均能满足2类功能区噪声标准要求,个别路段超标原因是本底噪声较大。有轨电车项目对噪声增加的贡献值较小,不会对噪声敏感点产生较大影响。  相似文献   
4.
GnRH主动免疫对绵羊血清睾酮含量的影响   总被引:4,自引:1,他引:4  
用碳二亚胺将GnRH与牛血清白蛋白联结,加入弗氏完全佐剂主动免疫8只3月龄雄性绵羊,结果表明免疫后至少在120天内会引起睾丸发育停滞,第二性征抑制,血清睾酮水平降低,其含量与手术去势组动物差异不显著,免疫组绵羊生长发育与手术组无明显差异,达到了去势的效果。  相似文献   
5.
贾靖霖  马明  李怀志  王帅 《中国饲料》2012,(3):16-18,30
试验将9只健康的卡拉库尔公羊分为3组,每组3只,分别为对照组、试验Ⅰ组和试验Ⅱ组,研究不同的小花棘豆添加量对卡拉库尔羊瘤胃内环境及微生物发酵参数的影响。结果表明,日粮中添加小花棘豆可降低卡拉库尔羊瘤胃液pH;随着小花棘豆添加量的增加,卡拉库尔羊瘤胃液氨氮含量升高,菌体蛋白含量下降;日粮中添加小花棘豆有促进瘤胃液总挥发性脂肪酸含量升高和乙酸/丙酸比降低的趋势。  相似文献   
6.
本研究通过对返青期和盛草期牧场放牧的高山美利奴种公羊进行营养监测,旨在掌握高山美利奴种公羊放牧地牧草营养物质的季节变化规律以及高山美利奴种公羊营养的盈缺,为其科学饲养提供理论依据.选择6只成年、健康、体重[(104.94±5.15)kg]相近的高山美利奴种公羊作为试验动物,采用粪袋全收粪和盐酸不溶灰分(AIA)结合法测...  相似文献   
7.
我们对新疆地方病防治研究所近年来从患附睾炎的公绵羊精液中分离出15株拟似布氏菌,除按常规检定外,还采用了S群及R群噬菌体裂解试验、绵羊附睾种血清的试管凝集反应,并对有的菌株做了DNA G+Cmol%含量测定,最后判定:在这十五株菌中有7株为绵羊附睾种布氏菌。  相似文献   
8.
The aim of the present study was to investigate the effect of kisspeptin-10 (Kp10) injection on semen characteristics, testosterone (T) production and sperm rheotaxis using microfluidic devices in immature ram. Computer-assisted sperm analysis (CASA) with controlled flow velocity was used to explore the kinetic parameters of sperm and positive rheotaxis (PR %). PR % was defined as the number of PR sperms over the number of motile sperms. Healthy Ossimi rams were randomly divided into two groups; a saline-treated control group and Kp10-treated one (5 µg/kg body weight). Treatments were given by intramuscular injection once a week for 1 month. After 1 month, the semen was collected and evaluated weekly for 6 weeks, while the blood samples were collected every 2 weeks for the next 8 weeks. Semen properties were significantly affected by Kp10 injection (p < .01). The Kp10 increased the volume, sperm concentration and percentages of live sperm compared with those of control. Additionally, sperm trajectories and rheotaxis get improved by the injection of Kp10 with time. Furthermore, kisspeptin improved the secretion of testosterone levels throughout the period of study. In conclusion, injections of the Kp10 had a positive impact on semen characteristics as well as improved sperm rheotaxis of Ossimi rams in subtropics.  相似文献   
9.
This work aimed to describe the activity of paraoxonase 1 (PON1) in serum, follicular fluid and seminal plasma of sheep. Average serum PON1 activity was 286.8 ± 96.2 U/ml in females and 237.6 ± 18.9 U/ml in males. There was a positive correlation between PON1 activity in serum and follicular fluid in females, being twice higher in serum than in follicular fluid (148.8 ± 15.7 U/ml). PON1 activity in males’ serum was 10‐fold higher than in seminal plasma (21.18 ± 14.2 U/ml), and there was no correlation between PON1 activity in both compartments. Finally, this work suggests that PON1 activity of in sheep is higher compared to other mammalian species, and there is an association between PON1 in serum and follicular fluid only.  相似文献   
10.
This study tested the effect of melatonin treatment, initiated in late February on reproductive traits of young rams. A total of 14 young Barbarine rams were used. Seven animals were treated with three melatonin subcutaneous implants (Melatonin) on 28 February while the remaining rams remained untreated (Control). After 60 days of melatonin administration, scrotal circumference reached average values of 32.1 ± 1.54 and 29.5 ± 1.0 cm for Melatonin and Control animals, respectively (P < 0.05). Semen characteristics did not differ between groups; melatonin treatment tended (P = 0.091) to increase sperm concentration 60 days after implantation when means reached 5.87 ± 0.703 and 4.61 ± 0.654 × 109 spermatozoa/mL for Melatonin and Control rams, respectively. Melatonin treatment significantly affected total activity time, number of lateral approaches and mount attempts in comparison to controls. During a 6‐h sampling period, mean plasma testosterone concentrations increased as a result of melatonin treatment (P < 0.001) and testosterone pulse frequency averaged 3.45 ± 2.24 and 1.25 ± 1.0 (P = 0.086) for Melatonin and Control rams. Data clearly suggest that abrupt treatment of young rams with melatonin implants in winter is sufficient to improve reproductive traits.  相似文献   
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