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91.
The current study was conducted to investigate the effect of stocking density (SD) on oxidative stress status and mammary gland permeability in early lactating dairy cows. Thirty‐two dairy cows were allocated into 16 blocks, basing on parity, previous milk yield, and body weight, and were then randomly assigned into one of the two treatments as follows: 75% (75SD) and 100% (100SD) SD. The cows were fed with same diet throughout the 8‐week experimental period. The milk yield and milk sample were collected on two consecutive days during the 8‐week experimental period weekly. Plasma samples were collected on fourth and eighth experimental weeks. Raw, energy‐corrected, and 4% fat‐corrected milk yield were significantly higher in 75SD‐cows than that of 100SD‐animals, respectively. The milk somatic cell count was lower in 75SD‐cows than that of 100SD‐animals. The levels of Na+, Na+/K+, bovine serum albumin and plasmin were lower in 75SD‐cows than those of 100SD‐cattle, respectively. The 75SD‐cows had reduced insulin and insulin/glucagon levels but higher prolactin and growth hormone concentrations, compared with those of 100SD‐animals, respectively. In conclusion, compared with low SD‐animals, early lactating cows with higher SD had higher oxidative stress status, which further led to a greater mammary gland permeability.  相似文献   
92.
Ethiopia has a large and diverse population of small ruminants, which contribute substantially to the livelihood and income of the rural poor and the country at large. However, the sector faces a number of challenges. Productivity per animal and flock offtake are both very low. Reasons attributed for the apparent low productivity are as follows: absence of appropriate breeding programmes, lack of technical capacity, inadequate and poor‐quality feeds, diseases leading to high lamb mortality, and underdeveloped markets in terms of infrastructure and information. Historically, sheep and goats have received little policy or investment attention. Genetic improvement of small ruminants could contribute to bridging the productivity gap. In the past, the government of Ethiopia has placed much emphasis on importing exotic genetics and cross‐breeding with local stock as a strategy for genetic improvement. However, this has not led to a significant productivity improvement and the programmes have generally been unsustainable. Currently, there is a change in approach and a recognition of the need to focus genetic improvement efforts on the local genetic resources that are well adapted to the diverse agro‐ecologies and production environments in the country. Community‐based breeding programmes (CBBPs), which focus on indigenous stock and consider farmers’ needs, views, decisions and active participation, from inception through to implementation, have been identified as programmes of choice. The Ethiopian government and the private sector need to invest in strategic areas around CBBPs to make the programme work for the poor and be sustainable in low‐input systems.  相似文献   
93.
为了促进广西隆林山羊杂交改良技术的应用,提高隆林山羊的生产效益,本研究以努比亚山羊、隆林山羊及努隆杂交F1代(努比亚山羊♂×隆林山羊♀)为研究对象,所有山羊都在相同水平下进行饲养管理,选取3个群体共205只山羊,分别对1、3、6月龄山羊的生产性能及体尺指标进行测定,选取6只6月龄的父母代及杂交F1代进行屠宰,取其背最长肌进行肉品质分析。结果表明,努隆杂交F1代经产母羊的产羔率、羔羊成活率与父母代差异不显著(P>0.05),初生重、不同月龄体尺指标与父母代差异极显著(P<0.01),努隆杂交F1代宰前活重、胴体重、净肉重、屠宰率、净肉率较隆林山羊都有显著提高(P<0.05),肌肉粗蛋白质含量、肌内脂肪含量、必需氨基酸、风味氨基酸、游离脂肪酸与父母代均有不同程度的提高。因此,努比亚山羊在改善隆林山羊体型、生长速度和肉品质上综合表现良好。  相似文献   
94.
高原山羊血气分析   总被引:1,自引:1,他引:1  
有血气分析仪对21只高原山羊进行血气分析,结果:pH7.35±0.05,PCO24.74±0.42kPa,PO23.79±1.05kPa,HCO-320.08±3.03mmol/L,TCO221.9±3.07mmol/L,BE-4.98±2.31mmol/L,SBC 20.25±2.65mmol/L,SBE-6.19±2.86mmol/L,O2S%49.47±14.8。表明血气值在不同性别、不同年龄间无显著差异(P>0.05)。  相似文献   
95.
Previous attempts to transfer embryos non-surgically to heifers have been rather discouraging. The present experiment describes a simple non-surgical technique where the 6½–7½ -day old embryo is placed in a 0.25 ml ministraw, fitted into a common insemination gun and transferred cervically to synchronized lactating dairy cows. Thirty-two viable embryos were transferred to the middle part of the uterine horn ipsilateral to the ovary containing the corpus luteum. It was easy to pass the cervix, and most embryos could be deposited in the horn within 1 or 2 min. Eighteen animals were diagnosed pregnant (56% ). It is conceivable that the easy atraumatic transfers and good management (feeding, oestrus control) of the recipients contributed to the high pregnancy rate.  相似文献   
96.
灌注葡萄糖对奶山羊乳腺营养摄取的影响   总被引:1,自引:0,他引:1  
本试验研究了阴外动脉灌注葡萄糖对乳腺营养物质吸收和乳成分的影响。选用体重和产奶量相近的4只泌乳中期关中奶山羊,做阴外动脉和腹部皮下静脉手术安装血插管,采用4×4拉丁方设计,每天分别灌注葡萄糖0、12、24g和36g。结果表明:乳脂率随葡萄糖灌注量的增加而显著降低(P0.01)。灌注36g/d处理组乳脂产量显著低于其他处理组(P0.01);葡萄糖灌注提高了奶山羊的产奶量,24g/d处理组的产奶量显著高于对照组(P0.01);36g/d处理组乳腺对葡萄糖的摄取量和乳糖的产量都显著高于对照组(P0.01)。甘油三酯和非脂固形物的含量各组间差异不显著(P0.05),但葡萄糖灌注提高了乳蛋白产量,其中24g/d处理组乳蛋白产量最高,并显著高于对照组(P0.05)。葡萄糖的灌注显著降低了奶山羊干物质的采食量(P0.01)。葡萄糖的灌注对乳腺氨基酸的摄取影响不显著。葡萄糖的灌注使氨基酸合成乳蛋白的产出率提高1%~9%,葡萄糖合成乳糖的产出率提高0%~5%,有效改善了乳成分。  相似文献   
97.
The influence of transgenic event CBH 351 (Starlink)-derived hybrid corn (SL) on the health condition, physiological function and lactational performance of dairy cows as well as the transfer of the cry9C gene and Cry9C protein present in SL to milk, blood, liver and muscles was examined, and compared with a diet containing non-transgenic (isogenic) control corn (non-SL). After adapting to a diet containing non-SL for 2 weeks, four Holstein cows were assigned to each of the non-SL and SL groups and were fed diets containing non-SL or SL, respectively, for 5 weeks. There were no significant influences on the physiological condition, milk yield or serum biochemical and hematological values after feeding with SL. There was also no influence on pH value, cell density of protozoa, or volatile fatty acid concentration and composition of rumen fluids. In addition, no significant differences were observed on histopathological examination of the major organs and tissues between the SL and non-SL groups. Moreover, the cry9C gene and Cry9C protein were not detected by the polymerase chain reaction method and ELISA in the milk, blood, liver and muscles of the cows at the end of the experiment.  相似文献   
98.
对王不留行的命名、植物形态、区域分布、药材鉴定、生物学特性、化学成分及其主要功能、临床应用进行了详细的论述,以期为王不留行的进一步研究提供理论依据,并有利于王不留行的深入探讨和研究,从而为壮大祖国中药医学事业的发展奠定基础。  相似文献   
99.
本研究通过饲养试验与屠宰试验来探讨限饲对绒山羊生产性能和屠宰性能的影响。将20只育成羊随机分成4组,即分别为自由采食组(AL)及自由采食组采食量的90%(IR90%)、80%(IR80%)和70%(IR70%)。正式试验期为90 d。结果表明:AL的日增重比IR90%组I、R80%组显著高出91.21%和194.92%(P<0.05),但IR90%和IR80%之间无显著差异(P>0.05),另外IR70%组的日增重为-6.3 g/d。宰前活体重、空体重、胴体重和屠宰率随着营养水平的降低有所减少(P<0.05)。随着营养水平的降低,肾周脂肪、系网膜脂肪占空体重的比例显著减少(P<0.05)。随着限饲强度的增加,日增重逐渐下降,体内脂肪沉积也随之减少。综合分析显示,绒山羊的限饲的阈值为IR80%。  相似文献   
100.
试验旨在研究哺乳母猪日粮中添加不同脂肪源对母猪繁殖性能和饲粮养分消化率的影响。选取第3胎次PIC母猪30头,随机分配到3个处理,即对照组、2%大豆油组和2%脂肪粉组,每个处理10个重复。试验从母猪分娩开始,到仔猪21日龄断奶时结束。结果表明:与对照组相比,脂肪粉组第3周平均日增重(ADG)和第3周窝增重分别提高了26.29%(P<0.05)和23.93%(P>0.05),大豆油组分别提高了19.72%(P>0.05)和17.85%(P>0.05)。且脂肪粉组的提高幅度最大。由此可知,饲粮中添加不同脂肪源可提高饲粮养分消化率,改善哺乳仔猪的生产性能,且脂肪粉优于大豆油。  相似文献   
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