选择性采食方式对生长猪的日粮选择及其生产性能的影响

为研究当猪能够从3种不同成分的颗粒料中作出采食选择时其是否能采食其所需的最佳日粮,特利用单独圈养的生长猪进行了一次试验。试验选用40头杂交猪(20头阉公猪,20头小母猪),其初始体重为22.0±2.1kg,在4周试验期中分成对照日粮组(C组)和选择性采食日粮组(CF组)。C组试验猪饲喂单一的全价料颗粒料,CF组试验猪能自由地从高能量颗粒料(E)、高蛋白颗粒料(P)和预混料/其它成分颗粒料(P/R)3种不同成分的颗粒料中挑选其所需的日粮。CF组试验猪利用一个分成3个隔间可同时供应3种颗粒料(每个隔间供应一种颗粒料)的长形料槽供料。所有日粮均自由采食。在采取选择性采食的方式中,小母猪所选择的高蛋白颗粒料要多于去势公猪,两者分别为222和193g/kgDM。而C组试验猪(无论小母猪还是去势公猪)均饲喂粗蛋白含量相同的日粮(即204g/kgDM;性别间差异显著P<0.05)。本试验不存在其他处理与性别之间的相互作用。对照组猪的净能摄入量高于试验,分别为13.8和10.3Mj/d(P<0.001)。小母猪的净能摄入量往往低于去势公猪,分别为12.6Mj/d和11.4Mj/d。CF组试验猪预混料/其它成分颗粒料的摄入量非常少(15g/d;13g/kgDM)。CF组仔猪日增重明显低于C组(779g/d和541g/d;P<0.001)。结果显示,当3种颗粒化的日粮配料被分别加入长料槽3个隔间中的其中一个时,仔猪不能选择最适合其生长的一种日粮配料。至于试验仔猪不能选择一种最适合其需要的日粮配料是否是由于特殊的器官感觉(如口味、风味或颗粒的物理性状)所致还有待进一步研究。如果弄清了这一原因,人们就能利用此方法去研究日粮成分(如次级配合料)或不同饲料处理方法的重要性。     

自由选择在评估猪对饲料原料采食偏爱中的应用

快速启动采食饲料是养猪业维持仔猪肠道功能、促进个体生长发育的关键.学习和研究动物采食行为、积累动物采食调控经验,挑选使用仔猪先天偏爱的原料调制出动物喜爱的饲料,可以帮助仔猪在断奶后的采食启动,从而达到合理使用配方策略,改善动物生产性能、提高投入产出比效率.在畜禽采食调控的研究过程中,常采用“让动物自由选择采食”的方法评估饲料原料、添加剂、加工工艺等日粮措施对动物采食量的影响.     

猪采食行为研究进展

本文主要从猪采食行为及其发生机制、目前国内研究采食行为的仪器及工作原理、猪采食行为特点、影响猪采食行为的因素四个方面综述了近年来在猪采食行为研究方面的进展和成果。     

驼羊放牧采食选择性的研究

本文利用链烷烃技术对驼羊放牧采食选择性进行了研究。研究表明：驼羊喜食禾本科牧草，且在日粮中的采食比例最大，平均达70％以上，其次为鼠尾草科，平均达10％以上。另外，研究还表明驼羊对其它牧草的采食程度也不一样。     

驼羊放牧采食选择性的研究

本文利用链烷烃技术对驼羊放牧采食选择性进行了研究.研究表明驼羊喜食禾本科牧草,且在日粮中的采食比例最大,平均达70%以上,其次为鼠尾草科,平均达10%以上.另外,研究还表明驼羊对其它牧草的采食程度也不一样.     

大约克夏猪采食行为的观察与研究

对大约克夏仔猪的采食行为进行了观察和研究。研究结果,可供大约克夏猪的培育和饲养管理作为参考。     

大约克生长猪采食行为观测与研究

本文对大约克生长母猪的采食行为进行了观测和研究,总结了其采食规律,以期为养猪生产和猪的行为学研究提供参考数据。选用体重（28．0±1．2）kg的大约克母猪60头,采用美国Osbem奥斯本工业公司FIRE全自动种猪生产性能测定系统,对猪采食行为进行精确的测定,结果表明,30-60kg体重大约克生长母猪,其平均日采食次数为9．5次;平均日采食量为1．48kg;平均日增重为（1．68kg;白天的采食量占全天的68．9％;全天采食量的高峰时间段为15：00-18：00。     

香猪采食前后胃液酸度的动态变化

试验研究了香猪胃液酸度的变化规律。结果表明，进食后胃液酸度逐渐增加，大约持续５ｈ。胃液中游离酸的含量较结合酸高。     

采食水平对东北民猪代谢热量的影响

以哈白猪为对照，研究２０℃条件下，低（Ｌ，７５０ｇ／ｄ），中（Ｍ１０５０ｇ／ｄ）高（Ｈ，１３００ｇ／ｄ）三种采食水平（饲料ＭＥ含量为１２．３７ＫＪ／ｋｇＣＰ：１６％）对体重２０～２５ｋｇ的民猪产热量的影响，研究结果表明，随采食水平提高，产热量有逐渐增加的趋势，但产不显著（Ｐ〉０．０５），三种采食水平下，民猪和哈白猪的产热量分别为３３．５，３４．５，３５．９和３１．９，３３．８，３４．９ＫＪ／ｋｇ＾     

芽孢杆菌的作用机理及其在断奶仔猪日粮中的应用研究

<正>随着生物技术的发展,益生素在生活和生产中的作用越来越重要。从应用范围讲,在药品、食品、饲料、饮料、肥料、生物、纺织以及环境处理等方面无处不用,而且都具有良好的经济效益。1999年,我国农业部公布了可以直接饲喂动物的12种饲料级微生物添加剂菌种:干酪乳杆菌、植物乳杆菌、嗜酸性乳杆菌、     

苜蓿草产品在养猪生产中的应用

目前影响我国养猪生产的主要因素是饲料蛋白质资源缺乏,产品药物残留严重。发达国家及一些发展中国家采取发展种草养畜解决这一问题,取得了成功经验。通过种草可以为养猪生产提供富含蛋白质、维生素、矿物质的青饲料,增加饲料的多样性,减少添加剂和药物使用,从而生产出安全的动物产品。苜蓿被誉为“牧草之王”,具有产量高、品质好、营养丰富、适口性好、含未知生长因子、抗旱抗寒、耐刈耐牧耐瘠耐盐碱等特点。在美国,苜蓿是仅次于小麦、玉米和水稻的第四大农作物。目前我国各地也已开始大面积种植,现将苜蓿草产品在养猪生产中的应用概述如下…     

Genetic variation and covariation in voluntary feed intake in pig selection programmes

Literature on the genetic variation in Voluntary Feed Intake (VFI) and traits related to VFI under ad lib. and restricted feeding has been reviewed. Also differences between breeds and selection lines are reviewed and discussed.Heritability estimates of VFI show average values of 0.12–0.59, with larger variation on real ad lib. feeding compared to “to appetite” feeding twice a day. It is also concluded that the genetic correlation between feed intake and gain is higher under ad lib. feeding than under restricted feeding, and that genetic correlation between daily gain and feed/gain decreases from about ?0.9 under restricted feeding to about ?0.6 under ad lib. feeding.Results from a Norwegian selection experiment indicate that there is no correlated response in daily feed intake (feeding “to appetite”) when selecting on backfat and daily gain, while other selection experiments, where feed conversion ratio has been the major component of the selection index, show reduced appetite.The present paper discusses the danger of reduced appetite in selection programmes that maximize short-term economic gain, and the importance of selection objectives and feeding regime on the genetic correlations between VFI and other production traits. A comparison is also made between population parameters of Norwegian and Danish Landrace pigs.     

The relationship between residual feed intake and feed intake behavior in group-housed Duroc barrows

Because feed is the major input in pork production, conversion of feed into lean tissue at minimum costs has been a focus for improvement. Several researchers have proposed using residual feed intake (RFI) rather than feed conversion ratio (FCR) for genetic improvement of feed efficiency. Little is known about the variation in RFI in pigs. As several studies suggest a greater RFI is related to greater animal activity levels, the current study investigated the phenotypic relationship between RFI and feed intake (FI) behavior of 104 group-housed growing Duroc barrows allowed ad libitum access to feed. Feed intake, BW gain, feeding time (TIME), feeding frequency (VISITS), RFI, and FCR were calculated for 5 periods of 14, 23, 28, 21, or 23 d in length (periods 1 through 5, respectively) on animals that were between 73 to 95 d of age at the start of the testing period. Barrows that grew faster consumed more feed (P < 0.001), and barrows that consumed more feed were fatter (P < 0.01). There were no correlations between VISITS and TIME, between VISITS and FI, or between VISITS and RFI. Barrows that spent more time at the feeder, however, consumed more feed (P < 0.05) and had greater RFI in periods 1, 3, and 5 (P < 0.05). As expected, FI and FCR were highly correlated with RFI (P < 0.001). These results suggest that a greater FI rather than greater feed intake activity resulted in greater RFI values.     

酸化剂、益生素和寡糖在断奶仔猪饲料中的应用研究进展

1酸化剂、益生素和寡糖在断奶仔猪饲料中的应用1.1酸化剂在断奶仔猪饲料中的应用目前,养猪生产中普遍存在的一个难题就是仔猪断奶后消化机能紊乱,导致生长受阻甚至死亡,原因之一是仔猪不能分泌足够的胃酸,胃中的pH值多在4.2以上;加上一些饲料原料的强缓冲能力(Bolduan,等,1988)     

氨基乙酰丙酸的生理作用及其在猪饲料中的应用

<正>氨基乙酰丙酸(Aminolevulinic Acid),又名δ-氨基乙酰丙酸、δ-氨基戊酮酸,简称ALA。熔点149～151℃,分子量131.2,化学式C5H9O3N。氨基乙酰丙酸是一种含氧和氮的碳氢化合物,是高等细胞的线粒体中柠檬酸循环(TCA)回路运转的时候产生的天然化合物,是一种广泛存在于细菌、真菌、动物及植物等生物机体活细胞     

The regulation of feed intake in ruminants

As in monogastric species, food intake in ruminants is regulated from meal to meal. The prandial stimulation of taste receptors and gastrointestinal chemo- and mechanoreceptors as well as hepatic chemoreceptors contributes to satiety. All these receptors are apparently connected with the brain by vagal afferents. A physiological satiety function of prandially released gastrointestinal and pancreatic hormones in ruminants is uncertain. Food stimuli affect feeding also through autonomic reflexes which regulate reticulo-rumen motility. All informations from the periphery are finally integrated in the hypothalamus. The exact role of the various neurotransmitters and neuropeptides involved in the control of feeding is as yet largely unknown.     

Correlated responses in sow appetite, residual feed intake, body composition, and reproduction after divergent selection for residual feed intake in the growing pig

Residual feed intake (RFI) has been explored as an alternative selection criterion to feed conversion ratio to capture the fraction of feed intake not explained by expected production and maintenance requirements. Selection experiments have found that low RFI in the growing pig is genetically correlated with reduced fatness and feed intake. Selection for feed conversion ratio also reduces sow appetite and fatness, which, together with increased prolificacy, has been seen as a hindrance for sow lifetime performance. The aims of our study were to derive equations for sow RFI during lactation (SRFI) and to evaluate the effect of selection for RFI during growth on sow traits during lactation. Data were obtained on 2 divergent lines selected for 7 generations for low and high RFI during growth in purebred Large Whites. The RFI was measured on candidates for selection (1,065 pigs), and sow performance data were available for 480 sows having from 1 to 3 parities (1,071 parities). Traits measured were sow daily feed intake (SDFI); sow BW and body composition before farrowing and at weaning (28.4 ± 1.7d); number of piglets born total, born alive, and surviving at weaning; and litter weight, average piglet BW, and within-litter SD of piglet BW at birth, 21 d of age (when creep feeding was available), and weaning. Sow RFI was defined as the difference between observed SDFI and SDFI predicted for sow maintenance and production. Daily production requirements were quantified by litter size and daily litter BW gain as well as daily changes in sow body reserves. The SRFI represented 24% of the phenotypic variability of SDFI. Heritability estimates for RFI and SRFI were both 0.14. The genetic correlation between RFI and SRFI was 0.29 ± 0.23. Genetic correlations of RFI with sow traits were low to moderate, consistent with responses to selection; selection for low RFI during growth reduced SDFI and increased number of piglets and litter growth, but also increased mobilization of body reserves. No effect on rebreeding performance was found. Metabolic changes previously observed during growth in response to selection might explain part of the better efficiency of the low-RFI sows, decreasing basal metabolism and favoring rapid allocation of resources to lactation. We propose to consider SRFI as an alternative to SDFI to select for efficient sows with reduced input demands during lactation.     

饲用抗生素替代物在养猪生产中的应用研究进展

养猪生产中抗生素的使用带来了巨大的危害和经济损失,在即将到来的无抗养殖背景下,寻求养猪生产中的抗生素替代物成为研究热点之一。文章结合近年相关研究,总结了植物提取物、寡糖和多糖、微生态制剂、中草药提取物、抗菌肽、酸化剂以及酶制剂等潜在的饲用抗生素可替代物在养猪生产中的应用效果,以期为养猪生产中配制无抗日粮提供策略和参考依据,促进养猪生产实现无抗养殖。