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61.
研究低聚木糖(XOS)对仔猪生长性能及对断奶仔猪肠道菌群的影响.选用杜×长×大三元杂交仔猪166头,随机分成3组,每组5个重复,于7日龄诱食后饲喂添加XOS和抗生素的饲料,以观察对仔猪生长性能和断奶仔猪肠道菌群的影响.结果表明:饲喂XOS能显著提高哺乳仔猪的生长性能,且在29~40日龄显著高于抗生素组(P<0.05);断奶前后XOS组乳酸菌的含量显著高于抗生素组和对照组,大肠杆菌数量差异不显著.  相似文献   
62.
Piglets with a high voluntary feed intake were compared with piglets fed restrictedly. Weaning induced changes in gut morphology and permeability. The intake level of dry pelleted feed affected intestinal villous architecture but did not affect permeability to small or large molecules from d0 to d7 post-weaning. A restricted feed intake level negatively affected gut morphology at d4 post-weaning. This effect could be alleviated but not completely prevented by a high voluntary intake of dry pelleted feed directly after weaning.  相似文献   
63.
A prospective longitudinal study was carried out on 39 outdoor breeding pig farms in England in 2003 and 2004 to investigate the risks associated with mortality in liveborn preweaning piglets. Researchers visited each farm and completed a questionnaire with the farmer and made observations of the paddocks, huts and pigs. The farmer recorded the number of piglets born alive and stillborn, fostered on and off and the number of piglets that died before weaning for 20 litters born after the visit. Data were analysed from a cohort of 9424 liveborn piglets from 855 litters. Overall 1274 liveborn piglets (13.5%) died before weaning. A mixed effect binomial model was used to investigate the associations between preweaning mortality and farm and litter level factors, controlling for litter size and number of piglets stillborn and fostered. Increased risk of mortality was associated with fostering piglets over 24 h of age, organic certification or membership of an assurance scheme with higher welfare standards, farmer's perception that there was a problem with pest birds, use of medication to treat coccidiosis and presence of lame sows on the farm. Reduced mortality was associated with insulated farrowing huts and door flaps, women working on the farm and the farmer reporting a problem with foxes.  相似文献   
64.
本试验采用1、2、4头份免疫剂量对重庆市荣昌县不同地区的仔猪进行PRRS免疫,然后在免疫后28 d和60 d分别采取血清用ELISA检测免疫抗体水平。结果显示:免疫4头份的抗体阳性率最高,为100%;其次为2头份免疫,抗体阳性率为91.67%;而1头份免疫的抗体阳性率仅为50%。进一步测定抗体滴度,发现2头份、4头份剂量在28 d和60 d的抗体效果差异性不显著。综合考虑,注射2头份高致病性猪蓝耳病活疫苗的免疫效果最佳。  相似文献   
65.
The effects of fibre in diets for periparturient sows are poorly documented. Three weeks before farrowing, 41 sows (LACT) were fed a diet containing 3.8% crude fibre. Other 40 sows (FIBRE) received a diet containing 7% crude fibre. We estimated the intestinal activity of the sows with a daily qualitative evaluation of their faeces. The FIBRE group had a qualitative faeces score value of 2.1 ± 1.3 and the LACT group had a value of 1.2 ± 1.1 (P < 0.001). Individual daily water consumption was higher in the FIBRE group than in the LACT group (P < 0.001). Piglet weight gain at day 5 was higher in the FIBRE group (P < 0.05). The energy balance related parameters did not differ between the treatments.Concluding, diets containing more fibre can be successfully used around farrowing reducing prolonged constipation of sows with no negative effect on their energy balance related parameters.  相似文献   
66.
李雪华  刘俊伟  郭延峰  崔金忠 《安徽农业科学》2010,38(17):9016-9017,9038
[目的]研究蓝耳康A对仔猪疫苗免疫效果和生长性能的影响,为今后绿色免疫增强药物的开发奠定基础。[方法]选择健康长大二元仔猪50头,随机分为2组,即对照组(Ⅰ组),试验组(Ⅱ组),25头/组。在25日龄时肌肉注射猪繁殖与呼吸综合征(PRRS)蜂胶灭活疫苗(2 ml/头)。用蓝耳康A拌料(10 ml/kg),饲喂试验组仔猪,7 d后,采用间接酶联免疫吸附试验测定猪繁殖与呼吸综合征抗体效价,E-玫瑰花环试验测定细胞免疫水平,并计算增重效果。[结果]蓝耳康A能提高猪繁殖与呼吸综合征抗体效价4个滴度,E-玫瑰花环形成率平均提高7%,平均日增重提高了15.68%。[结论]仔猪饲料中添加蓝耳康A能明显提高动物机体的免疫功能,增加仔猪的日增重,以及提高其生产性能。  相似文献   
67.
早期断奶仔猪一方面消化系统发育不成熟,吸收养分能力差,消化酶和胃酸分泌不足,正常的肠道微生物系统尚未建立;另一方面断绝了从母体获得被动免疫的来源,而自身的主动免疫发育尚未成熟。所以断奶应激造成早期断奶仔猪出现消化不良、生长迟滞、抗病力弱等"仔猪早期断奶综合症"。仔猪肠道对日粮抗原过敏从而导致肠道损伤是断奶后腹泻的根本原因。早期补饲、逐步断奶、去母留仔、合理饲喂可预防早期断奶仔猪腹泻。  相似文献   
68.
华南虎哺乳期母幼行为的初步研究   总被引:2,自引:0,他引:2  
对梅花山华南虎繁育研究所内 4号母虎及其所产幼虎的母幼行为进行了初步研究 ,着重描述了华南虎母幼的各种行为 ,并对其中的一些行为作了初步探讨。母幼间接触的部位主要是头部等感官较敏感区域 ,通过各种接触是建立母幼友好、亲昵关系的主要途径。母虎主要通过哺乳、舔、嗅等行为与幼虎接触 ,其次是拱、衔、护幼行为等 ;而幼虎主要是通过吮乳、舔、嗅闻与母虎接触 ,其次是叫等方式  相似文献   
69.
畜牧业是新农村建设的萤要组成部分,加快农区畜牧业发展对于调整农业产业结构,发展农村经济,增加农民收入,加快新农村建设步伐,实现小康社会具有十分重要的意义。当前,随着社会主义市场经济的深入发展和西部大开发战略的有效实施,互助县畜牧业进入了一个新的发展时期,我们既面临着良好的发展条件和机遇,也面临着新的挑战和问题。为抓住机遇,实现畜牧业发展的新突破,推动新农村建设.提出以下建议和思路,以供参考。  相似文献   
70.
Crating sows in farrowing systems greatly restricts their normal behaviour (e.g. movement, nest-building, leaving the nest site for defecation), which is usually justified by the assumption that piglet mortality is higher with loose-housed sows. Based on experiments showing that this is not the case, farrowing crates were banned in Switzerland in 1997, with a 10-year transitional period. Since then, many farms have introduced loose farrowing systems, enabling an analysis of risk factors for piglet mortality in crateless farrowing systems based on a large sample size. Data from a Swiss sow recording scheme (UFA2000) were analysed using generalised linear mixed-effects models with an underlying Poisson distribution. Average total piglet mortality for the years 2002 and 2003 on 99 farms (N = 12457 litters) with loose farrowing systems amounted to 1.36 liveborn piglets per litter. The number of crushed piglets was 0.64 piglets per litter, whereas the number of piglets that died for other reasons was 0.72 piglets per litter.Herd size, pen size, possibility of confinement of the sow, presence of piglet protection bars and year of data collection did not significantly influence total piglet losses, losses due to crushing and losses due to reasons other than crushing. With greater litter size at birth, significantly more losses occurred due to all reasons (total, crushed, others). Total piglet mortality and losses for reasons other than crushing were significantly higher in older sows. Losses were therefore mainly attributable to sow-related characteristics rather than to the design of the farrowing pen.  相似文献   
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