漫谈养殖户选择饲料之误区

随着现代养殖业规模化发展,养殖户对科学养殖的认识也越来越深入,但由于地域性的差别及养殖户养殖习惯的不同,科学养殖的观念在具体实施上还存在很大的差距。另外,养殖户是一个比较大的且较分散的群体,这个群体与其他经营群体相比,存在着知识面窄,市场意识差等弱点,在饲料的选择上还存在着很大的误区。本文从以下9个方面概述了目前养殖户在选择饲料时存在的误区。     

养殖户选择饲料的八误区

1"低价格的饲料可以降低饲料成本"饲料成本约占养殖成本的70%～80%。因此,许多饲料厂利用多数养殖户非常计较饲料价格却忽视畜禽的采食量这一重要指标的心理,采取低价即选用低质量的饲料原料来代替高质量的饲料原料,靠增大采食量来保证畜禽的生产水平。     

养殖户选择饲料的误区

一般饲料成本约占养殖总成本的70％左右,由于认识水平或养殖水平不高,使得目前仍有许多养殖户在选择饲料的过程中或多或少存在一些误区,直接影响了养殖经济效益。 误区之一:喜欢选择价位低的饲料。结果是,虽然在短期内畜禽靠自我生理调节使生产水平得以维持(如有时可见蛋重略大),但鸡的采食量却大幅度增加。猪则表现为生长缓慢,使单     

奶牛养殖户养殖误区知多少

随着奶牛养殖业的降温，奶牛及牛奶的价格不断下降，奶牛养殖户中出现了1／3赚钱、1／3持平、1／3赔钱的局面。其实出现这种局面并不是说奶价下降或奶牛降价导致部分牛户不盈利，而是过去粗放的生产管理模式已经不适合在利润空间下降的情况下继续使用。下面将农户或饲养场中常见的一些养殖错误介绍如下。     

养殖户选购配合饮料有误区

随着畜禽养殖业的快速发展，大多数畜禽养殖户逐步认识到了配合饲料在畜禽生产中的作用，越来越多的使用配合饲料饲喂畜禽，但由于对配合饲料方面的知识了解不多，在选购配合饲料时存在一些误区，影响了养殖效益的提高。     

专业养殖户常见用药的误区及改进措施

近年来,养殖业由传统的散养模式向集约化、规模化、专业化养殖模式转变,畜禽疾病日益复杂化。因此,畜禽疾病防治中,用药就成了关键问题。     

养殖户饲料应用误区

1.自配方随便①配方照抄照搬,应用不灵活。很多人只是参照某些资料中提供的参考配方,而不结合自己的实际情况,结果配出的饲料既不能很好地满足营养需求,又不能做到价格合适。②对原料的营养标准缺乏基本常识。当前原料市场上产品众多,价格各异,质量差别较大,配制合格的饲料需要掌握各种营养标准。③均匀度差。自配料者大多采用人工搅拌或利用一些低档次的搅拌机,加工出的饲料在均匀度上没有保证,特别是一些小量成分的均匀度更难达到要求。因此,建议尽量减少自配料的使用。2.浓缩料蛋白质含量越高越好由于一些厂家的宣传和误导,使很多养殖者…     

养殖户在饲料选择上de八大误区

饲料成本占养殖成本的70％～80％，因此饲料成本的高低直接影响到养殖专业户的生产水平和经济效益。如何选择饲料原料及全价饲料是每一个养殖户都非常重视的问题，但是许多养殖户在饲料的选择上还存在一些误区，从而影响了养殖户的经济效益。     

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.     

Effect of selection for residual feed intake on feeding behavior and daily feed intake patterns in Yorkshire swine

Residual feed intake (RFI) is a measure of feed efficiency defined as the difference between observed and predicted feed intake based on average requirements for growth and maintenance. The objective of this study was to evaluate the effect of selection for decreased RFI on feeding behavior traits and to estimate their relationships with RFI. Three data sets from the 4th and 5th generations of a selection experiment with a line selected for reduced RFI (LRFI) and a randomly selected control line (CTRL) were analyzed. Lines were mixed in pens of 16 and evaluated for feeding behavior traits obtained from a single-space electronic feeder over a growing period of ~3 mo before ~115 kg. The following traits were evaluated as averages over the entire test period and over the first and second half of the test period: number of visits per day and hour; occupation time per day, visit, and hour; feed intake (FI) per day, visit, and hour; and FI rate per visit. Models used included fixed effects of line and feeder, covariates of on-test age and FI per day, and random effects of pen, on-test group, sire, and litter. Repeated measures models were used to analyze feeding patterns during the day. The LRFI pigs had significantly less FI per day than CTRL pigs for all 3 data sets. With adjustment for FI per day, line differences of all traits were in the same direction for all 3 data sets but differed in significance and size. Feed intake per visit and hour and visits per day and hour did not differ between lines, but the trend was for LRFI pigs to have fewer visits, in particular during peak eating times. The LRFI pigs had a greater feeding rate and less occupation time per day, visit, and hour than CTRL pigs, but this was not significant for all data sets. Correlations of RFI with FI per day and visit and visits per day were positive. Average daily gain was positively correlated with FI per day and visit and occupation time per visit but negatively correlated with visits per day. Feed intake per day was positively correlated with backfat. In conclusion, feed efficiency may be affected by FI behavior because selection for decreased RFI has resulted in pigs that spend less time eating and eat faster.     

Bayesian analysis of the effect of selection for residual feed intake on growth and feed intake curves in Yorkshire swine

Gompertz growth functions were fitted to longitudinal measurements of daily feed intake (DFI) and BW of 586 boars and 495 gilts from a selection experiment in Yorkshire pigs for residual feed intake (RFI). The selection experiment consists of a line selected for low residual feed intake (LRFI) for 5 generations and a randomly selected control line (CTRL). The objectives of this study were to use Bayesian methods to estimate genetic parameters of the Gompertz curve parameters for DFI and BW, to evaluate the effect of selection for reduced RFI on the Gompertz parameters and shape of curves for DFI and BW, and to develop methodology for quantifying genetic variation at the level of the original phenotypes for DFI and BW based on the Bayesian analysis of the nonlinear model. Separate analyses were done for boars and gilts and for BW and DFI. A hierarchical model was specified in 2 levels: in the first level, the Gompertz function was modeled for each pig, and at the second level, a 3-trait linear mixed model was fitted to the 3 Gompertz parameters (asymptotic value, inflection point, and decay parameter), with fixed effects of line by generation and random effects of additive genetic and environmental effects. Bayesian methods were used to combine the 2 levels of modeling. A total of 30,000 random samples of the posterior distributions after convergence of Markov chains were used for inference. Posterior means of heritability within the first level of the model for the asymptotic value, inflection point, and decay parameter for DFI were 0.74, 0.66, and 0.82 for boars and 0.79, 0.70, and 0.57 for gilts; corresponding estimates for BW were 0.64, 0.58, and 0.60 for boars and 0.46, 0.35, and 0.33 for gilts. For DFI, LRFI boars had a reduced mature DFI (2.91 vs. 3.20 kg/d) and an earlier inflection point (85 vs. 95 d) compared with CTRL boars. For BW, LRFI boars had a lighter mature BW (279 vs. 317 kg), an earlier inflection point (184 vs. 198 d), and a decreased decay parameter (127 vs. 134 d) compared with CTRL boars. In contrast, LRFI gilts had a later inflection point (225 vs. 200 d) and a greater decay parameter (172 vs. 143 d) than CTRL gilts for BW. The other Gompertz curve parameters for DFI and BW for boars and gilts were considered not different between lines, with posterior probabilities of the line differences being greater than zero ranging from 0.1 to 0.9.     

基于猪剩余采食量的分化选择与遗传进展

猪剩余采食量(Residual Feed Intake,RFI)是一个有效评价生猪饲料效率的新性状,用剩余采食量来提高生猪饲料效率是当前养猪界的重要研究方向。本试验测定了2个世代198头军牧1号公猪的周采食量、日增重(ADG)和背膘(BF)等性状,和母猪453头母猪日增重(ADG)和背膘(BF)等性状,然后建立了饲料效率育种值估计模型,以剩余采食量(RFI)为主选性状,ADG和BF为辅助约束性状,通过遗传评估按育种值高低分为高RFI和低RFI 2个群体。在这2个分化群体内进行同质选配2个世代后计算其遗传进展。结果显示,RFI、ADG、BF的遗传力分别为0.15、0.22、0.28。G0代选择群体高、低RFI之间,RFI、ADG、BF性状的育种值差异分别是1.48、0.40、0.56个标准差;G1代高、低RFI测定群体之间3个性状的育种值差异分别是1.52、0.56、0.18个标准差。原始群体与G1代测定群体相比,高RFI群体的RFI、ADG、BF的遗传进展分别是0.732、-0.274、0.101个标准差,低RFI群体的RFI、ADG、BF的遗传进展是-0.788、0.283、-0.079个标准差。此外,肉质检测结果显示2群体间无显著差异。结果表明,用RFI作为主选性状可有效改变猪的饲料效率,建立饲料效率分化品系,遗传进展良好。     

电子商务助推饲料企业升级的模式选择与实践路径

互联网的普及以及消费者消费观念的转变,使得电子商务对我国各行各业发展都产生了重要影响.作为经营与发展模式都较为传统的饲料行业,在当下转型升级的过程中,必须顺应这一趋势,借助电子商务改造商业模式.基于这一背景,本文首先论述了饲料行业发展电子商务的必要性;其次,分析了在饲料企业转型发展模式选择中电子商务的应用;最后,介绍了...     

基于饲料质量选择分析养殖户经济现状

本文通过选取河北省、辽宁省两地,以生猪养殖户为例对饲料质量的选择情况展开调研,通过养殖户对饲料质量的总体需求情况、不同养殖规模两视角,对养殖户的经济现状进行分析。调研结果表明:两地区的养殖户饲料粮使用占比较高,工业饲料占比较少,农副产品使用情况存在较大差异,主要受养殖规模、饲料价格及经济情况影响。因此,饲料质量选择在一定程度上受养殖户经济状况影响,而选择优质放心的饲料是每个养殖户提高经济收益的关键。     

饲料用药、饲料添加剂与饲料安全

近年来,由饲料安全问题引发动物食品安全问题的事件时有发生,且有愈来愈严重的趋势。1999年,比利时发生的“二恶英”饲料污染事件,直接经济损失达25亿欧元,并导致比利时政府集体辞职。2000年英国的“疯牛病”再次爆发,席卷欧洲。据报道,在韩国一位30岁男子被怀疑染上“疯牛病”,如果属实,这是迄今为止在欧洲以外的国家首次发现人的“疯牛病”病例。“二恶英”与“疯牛病”均与饲用油脂和动物肉骨粉被污染有关。我国至今虽未发现有“二恶英”、“疯牛病”的污染,但违禁药品的“暗地”使用已致多起使人中毒事件。1998年5月,香港居民因食用内地供港猪内脏(含盐酸克伦特罗),造     

The regulation of feed intake and selection with special reference to poultry]

Feed intake is regulated in a dialogue between the animal and the feed, which is influenced by numerous factors. The hypothalamus has a central integrative function. Furthermore, caudal brain areas (medulla oblongata, pons) are of importance because these areas are relays of peripheral signals and gustatory afferents. All peripheral informations are integrated by various neurotransmitters and neurohormones. The function of this neuronal system is not exactly known yet. Sensorial informations, mechano-, chemo- and osmoreceptors of the gastrointestinal tract and gastrointestinal hormones are discussed as influences of the periphery. The physiological satiety function of cholecystokinin is questionable in poultry. Hepatic chemoreceptors, which are activated by various metabolites, influence the amount of feed ingested. The feed choice appears to be regulated by the same mechanisms. Our knowledge about the translation of peripheral signals into choice behaviour by changes of neurotransmitter systems is limited.     

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.     

Effect of selection for growth on normal and reduced protein diets on weight gain, feed intake, feed efficiency and body composition in mice

Mice selected for weight gain from 3 to 9 weeks of age on a normal (N) protein diet containing 19.3% protein and a reduced (R) protein diet with 5.1% protein were reared on both diets in generations 7 and 9. The lines NH, NC, NL, RH, RC and RL (H, high; C, control; L, low) were tested for weight gain on diet N and R and for feed intake and feed efficiency on diet N in generation 7. In generation 9, the lines were tested for body composition traits (fat, protein and water percentage) at 3, 6, 9 and 12 weeks of age on both diets. A significant (p < 0.0001) genotype × environment interaction for growth rate was observed in generation 7. Weight gain at both the protein levels was best improved by selection at the protein level itself. Furthermore, the ranking of the lines on diet N was similar for weight gain, feed intake and feed efficiency. In generation 9 at 9 weeks of age, the ranking of the lines for fat percentage was equal to the ranking for weight gain in generation 7 on both test‐diets. The association between weight gain and protein or water percentage was less pronounced, particularly on diet R. These results suggest that the largest genetic improvement in growth rate is obtained when the protein content of the feed is the same in selection and production. However, when selection is carried out in one environment while the animals have to perform under conditions with varying nutrient protein contents, selection in an inferior environment may be advantageous.