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1.
为明确漏缝地板发酵床对育肥羊养殖过程氨(NH3)和温室气体排放特征的影响机制,本研究设置地面和漏缝地板发酵床两个试验处理,测定分析了育肥羊养殖过程NH3、氧化亚氮(N2O)、二氧化碳(CO2)和甲烷(CH4)的排放特征,并采用宏基因组学解析了影响上述气体排放的微生物学机理。试验结果表明,与地面相比,漏缝地板发酵床能够显著降低育肥羊养殖过程的NH3排放(P<0.05),其NH3排放速率为21.64~58.92 mg·m-2·h-1,NH3累积排放量为86.36±1.06 g·m-2,减排率达58.60%。漏缝地板发酵床同样也能显著降低育肥羊养殖过程的CH4排放速率(P<0.05),其CH4累积排放量为26.66 g·m-2,减排率可达64.42%。然而,漏缝地板发酵床会使得...  相似文献   
2.
为进一步研究不同肉羊品种与湖羊杂交F1代羔羊育肥效果,本试验选择国外优良的肉羊品种杜泊羊、无角陶赛特羊和萨福克羊作父本,国内优良地方品种湖羊作母本开展杂交试验研究,所获得的杂交F1代羔羊在全舍饲条件下进行育肥。测定杂交F1代羔羊初生重、不同月龄体重和平均日增重等生长性能。结果表明:试验A组(杜泊公羊与湖羊母羊杂交F1羔羊)、试验B组(无角陶赛特公羊与湖羊母羊杂交F1羔羊)、试验C组(萨福克公羊与湖羊母羊杂交F1羔羊)6月龄平均重分别为44.76±3.62 g、 43.65±4.18 g、43.28±3.34 g,均极显著高于对照组D 6月龄平均重36.32±3.86 g,差异极显著(P<0.01)。试验A组、B组、C组与对照组D相比较,试验A组、B组、C组每只羊的利润较对照组分别多收入80.02元、69.74、42.74元,差异极显著(P<0.01),其中试验A组的生长性能和利润均优于试验B组和C组,差异显著(P<0.05)。  相似文献   
3.
为探究附红细胞体在内蒙古呼和浩特市托克托县地区的流行情况,接诊呼和浩特托县地区某东佛里生奶绵羊养殖场病例,该场近一周多圈舍出现产奶羊只体温升高、精神沉郁、瘫软、食欲减退或废绝等症状,有出现症状1 ~ 2 d迅速死亡病例,也有使用抗生素硫酸庆大霉素-青霉素联用结合补液治疗1周无好转或死亡病例,死亡总数超8只,仍有10余只相似症状正在接受治疗。经现场剖检、圈舍环境调查、样品实验室检测,结合临床诊疗,确诊此次疫情为奶绵羊附红细胞体病,且周边羊养殖场(户)羊只也存在附红细胞体感染。说明附红细胞体在托克托县呈地方性流行。  相似文献   
4.
Grazing modifies the aboveground soil and plants of rangeland ecosystems. This study was conducted to determine the effects of various grazing intensity levels on soil bulk density, soil pH, soil electrical conductivity (EC), soil total organic carbon (TOC), aboveground biomass production, plant community richness (N), and vegetation diversity (H) in Gian Rangeland, Hamedan Province, Iran. Soil and vegetation samplings were conducted based on the randomized systematic method. Soil and vegetation samplings were carried out along 100-m-long transects placed at 100, 200, 400, 800, and 1600 m running perpendicular to six sheep corrals. The effects of various grazing intensities on studied parameters were detected by analysis of variance (ANOVA) (at α = 0.05). Results of this study indicated the soil bulk density, EC, TOC, aboveground biomass production, plant community richness, and vegetation diversity values were altered significantly at different distances from the sheep corrals. However, soil pH was not significantly affected by various grazing intensities.  相似文献   
5.
Feeding trials were conducted with stall-fed sheep parasitized with Haemonchus contortus. For 10 days they were offered 250 g of a concentrate feed that had been top-dressed with desiccated chlamydospores of Duddingtonia flagrans at 1×105, 5×105, 1×106 or 2×106 chlamydospores/kg body weight. Pooled faeces from each group on day 7 of spore feeding were spread on different pasture plots. On day 28 after the start of spore feeding, further pooled faeces from each group were spread on the same plots. The larval burdens on the plots were monitored for 2 months and the larval harvest from in vitro faecal cultures were monitored regularly. The application of 1×106 or more spores/kg body weight virtually eliminated larvae from both the pasture and the faecal cultures. The application of as few as 1×105 spores/kg body weight had a profound impact on larval recovery. The effect persisted while the spores were being fed but not for more than 4 days following discontinuation of spore feeding. Top dressing supplementary feed with dried chlamydospores offers a potential way of using D. flagrans for biological control of the pre-parasitic stages of H. contortus.  相似文献   
6.
2010年春季以来,在辽西部分养羊户中的断奶羔羊及育成羊群中出现不明原因的死亡现象,经抗生素等药物进行常规治疗无效,死亡率达12%.临床症状为可视黏膜及皮肤重度黄染并排血红蛋白尿,最后因肝肾功能衰竭死亡;病理剖检变化为肝、肾变性坏死及实质性器官出血性变化为主.通过流行病学调查,并对病死羊进行病理剖检及对饲料真菌毒素的检...  相似文献   
7.
Liveweight gain was evaluated in tropical Dorper X Pelibuey lambs under intensive continuous grazing of native grasslands dominated by Paspalum notatum (PN) or Axonopus compressus (AC) in the subtropics of Central Mexico. Two trials were undertaken. Trial 1 lasted 12 weeks with 10 lambs (initial weight 18 +/- 2.57 kg, 3 months old) per treatment in 2002, and Trial 2 for 13 weeks with 8 lambs (initial weight 24.0 +/- 2.0 kg, 4 months old) per treatment. Lambs were weighed once per week, and liveweight change was estimated by linear regression over day of the experiment, using individual regression coefficients as unbiased estimates of daily liveweight change; analysed in a random block design. Lambs on Trial 1 gained 0.061 kg/lamb/day on PN and 0.047 kg/lamb/day on AC (P > 0.05) at an overall mean stocking rate of 25 lambs/ha. In Trial 2, liveweight gain was significantly larger in PN (0.060 kg/lamb/day) than on AC (0.043 kg/lamb/day) (P < 0.05), at a mean stocking rate of 21.5 lambs/ha. It is concluded that intensive continuous grazing of native grasslands in the subtropics of the highlands of Central Mexico enables moderate liveweight gains for weaned lambs during the rainy season; with better results in grasslands dominated by Paspalum notatum.  相似文献   
8.
探索能扎根农牧区的利用肉羊杂种优势的综合配套技术新途径,通过杂交、育肥、羊群结构等多方面的比较试验,结果:三洛来公羊与当地母羊杂交一次(人工授精,东部农业区宜于8-9月,环湖牧区11月)羔羊生后随母羊放牧、放牧十补饲和全舍饲育肥160-215天,6-7.5月龄时活重27.46-32.17kg,胴体重11.67-15.97kg,比放牧饲养的同龄羔羊胴体重增加2.75-7.17kg,经济效益提高30.83%-81.48%,杂种羔羊9月份体重最高,适宜的屠宰时间是9月底或10月初和每年的2-3月份;肉羊生产的优化羊群结构:成年母羊占存栏羊60%以上,公羊占3%-4%,每年补充小母羊20%以上。试验结果证明:以夏洛来羊杂交组合为主的肉羊生产综合配套技术,在我省东部农业区和环湖牧区是可行的,为提高羊肉产量和质量,增加农牧民收入开辟了新途径,经济、社会和生态效益显著。  相似文献   
9.
根据高原地区"春乏"期间,牛、羊因胃肠道线虫病引起死亡严重的突出情况,自列项目,在全州范围划为三大区域,以项目区为中心,在牛、羊发病率和死亡率相对高的乡(镇)、村设点,将93330头(只)牛、羊分为三个组,作为高原地区牛、羊胃肠道线虫病防治技术模块,结果3个试验组用药前胃肠道寄生虫感染率均为100%,早晨在放牧前投喂赛爱吉夏结、克虫特和丙硫苯咪唑等药物后,7 d粪检EPG,虫卵转阴率和虫卵减少数均为100%。间隔7 d重复驱虫1次,防治效果显著。有计划的用驱虫药丙硫咪唑,克虫特、伊维菌素。在每年春季2~3月,秋季8~9月份进行两次驱虫。可提高牛、羊有机体的免疫力,降低牛、羊胃肠道线虫病的发病率和死亡率,减轻对养殖业的危害。  相似文献   
10.
The literature mostly indicates that docking fat-tailed lambs initially reduces growth but that post-weaning growth and feed conversion efficiency then increase. The amount of fat deposited, the total separable lean meat to fat ratio and the meat quality all increase, while the percentage of bone in the carcase either decreases or does not change in the carcases of the docked lambs. Wool growth and characteristics are, in general, not affected and reproductive traits in ewes and lambs are improved by docking. The rectal temperature, respiration rate and pulse rate are decreased following docking. The concentrations of immunoreactive beta-endorphin and cortisol in the plasma and the incidence of foot stamping and restlessness, as indicators of stress, increase after docking. Other constituents of the blood are not significantly altered following docking or by the methods of docking. Docking of fat-tailed sheep using rubber rings at one day of age can be recommended. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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