共查询到20条相似文献,搜索用时 187 毫秒
1.
2.
动物采食量是限制动物生产性能及基因潜力发挥的最主要因素之一,提高动物采食量已逐渐成为动物营养生理研究的一大热点。文章主要对猪的采食量的重要性,采食量的调节机制、影响采食量的因素及调控采食量的因子进行综述。 相似文献
3.
4.
5.
采食量是影响动物生产性能的决定性因素,也是提高动物生产效率的关键。文章阐述了猪采食量的反馈调节、猪的采食能力、影响动物采食量的短期调控因素和长期调控因素,指导在实际生产中如何提高猪的采食量,减少粪便量,提高生产性能。 相似文献
6.
7.
《家畜生态学报》2021,42(6)
为了研究北方寒冷地区猪舍环境温湿度对育肥猪采食量的影响规律,试验选取内蒙古农业大学海流图科技园区生猪养殖场的30头育肥猪,按不同体重分3组连续测定96 d,分析环境温湿度对不同体重育肥猪采食量的影响。结果表明:舍内温度在10~31℃范围内,随着温度的升高不同体重猪的日均采食量先减小,后缓慢增大最后减小。猪舍温度对不同体重育肥猪采食量的影响极显著(P0.01)。当猪舍相对湿度在45%~90%范围内变化时,不同体重的育肥猪日均采食量随着湿度的增加先增大再减小。猪舍湿度对不同体重育肥猪采食量的影响极显著(P0.01)。在北方干旱寒冷地区实际生产中,育肥猪舍温度控制在17~24℃,湿度应控制在45%~75%为宜。 相似文献
8.
《畜牧兽医科技信息》2017,(11)
<正>1猪采食量的控制机制猪采食量的控制机制可被分解为3个水平。在代谢水平上,营养物质的浓度、代谢产物或激素的水平可以刺激神经系统,促进动物采食开始或停止;在消化系统水平上,消化道食糜的量决定动物是否摄取更多的食物;外部环境的影响,如温度的变化会影响食物的采食量。猪的采食行为是由位于大脑下面的下丘脑所控制的。第一个是采食中枢(位于下丘脑外侧),在没有第二个中枢作用的情况下,会使动物不停地 相似文献
9.
猪采食量变化的成因分析与对策 总被引:6,自引:0,他引:6
在不影响猪健康的前提下,尽可能多的摄食是猪快速生长的必要条件.作者在阐明猪采食量调控机制、分析采食量变化原因的基础上,结合生产实际,从日粮配方设计、饲养管理方面提出了应对采食量变化的措施,以期提高养猪经济效益. 相似文献
10.
11.
12.
13.
提高猪饲料效率的测定与选择 总被引:1,自引:0,他引:1
为提高猪饲料效率的选择,本试验测定一些与猪饲料效率相关的生产性状并进行遗传评估。方法:测定60头军牧1号白猪后备公猪的采食量、体增重、背膘厚等生产性状,用猪剩余采食量(RFI)和饲料转化率(FCR)作为评价饲料效率的两个指标,并对其遗传参数进行评估。结果:测定期内军牧1号公猪群体FCR均值为2.61,RFI的标准差为77.52。RFI与FCR的遗传力分别是0.35、0.33,RFI与ADFI(日采食量)、ADG(日增重)、BF(背膘厚)的遗传相关分别是0.89、0.12、-0.05,FCR与ADFI、ADG、BF的遗传相关分别是0.55、-0.65、-0.11。结论:军牧1号白猪品种内饲料效率存在较大的遗传差异,由于RFI与ADG遗传相关很低,因此用RFI作为选择性状可有效提高猪的饲料效率。 相似文献
14.
Application of feed processing methods and use of exogenous feed additives in an effort to improve nutrient digestibility of plant-based feed ingredients for swine has been studied for decades. The following review will discuss several of these topics, including: fiber characterization, impact of dietary fiber on gastrointestinal physiology, energy, and nutrient digestibility, mechanical processing of feed on fiber and energy digestibility, and the use of exogenous enzymes in diets fed to growing pigs. Taken together, the diversity and concentration of chemical characteristics that exists among plant-based feed ingredients, as well as interactions among constituents within feed ingredients and diets, suggests that improvements in nutrient digestibility and pig performance from mechanical processing or adding exogenous enzymes to diets fed to swine depends on a better understanding of these characteristics, but also relating enzyme activity to targeted substrates. It may be that an enzyme must not only match a target substrate(s), but there may also need to be a ′cocktail′ of enzymes to effectively breakdown the complex matrixes of fibrous carbohydrates, such that the negative impact of these compounds on nutrient digestibility or voluntary feed intake are alleviated. With the inverse relationship between fiber content and energy digestibility being well described for several feed ingredients, it is only logical that development of processing techniques or enzymes that degrade fiber, and thereby improve energy digestibility or voluntary feed intake, will be both metabolically and economically beneficial to pork production. 相似文献
15.
16.
17.
Mycotoxins and reproduction in domestic livestock. 总被引:10,自引:0,他引:10
Molds are parasitic plants that are ubiquitous in livestock feedstuffs. Even though molds themselves reduce the quality of grains, their synthesis of chemical substances termed mycotoxins causes the greatest monetary loss to the animal industry. Five major mycotoxins that impair growth and reproductive efficiency in North America are aflatoxins, zearalenone, deoxynivalenol, ochratoxin, and ergot. Aflatoxins are produced by Aspergillus flavus and Aspergillus parasiticus. Consumption of grains containing aflatoxins by swine affects reproduction indirectly by reducing feed intake and growth. In swine, aflatoxins impair liver and kidney function, delay blood clotting, increase susceptibility to bruising, and interfere with cellular humoral immune systems. Ruminants are comparatively resistant to aflatoxicosis, but presence of aflatoxins in milk of dairy cows is closely monitored for human safety. Depending on environmental conditions, Fusarium roseum can produce either zearalenone or deoxynivalenol. Days 7 to 10 postmating seem to be a critical period of gestation for zearalenone to exert its detrimental actions on early embryonic development. Presence of deoxynivalenol in swine feedstuffs decreases feed intake, causes feed refusal, and induces occasional vomiting. Several species of Penicillium and Aspergillus produce ochratoxin, a mycotoxin that causes necrosis of kidney tissue. Ergot alkaloids produced by Claviceps purpurea on wheat can cause reproductive problems and are associated with lactational failure in swine. Various methods have been developed to remove mycotoxins from infected feedstuffs. Chemical analyses in laboratories as well as diagnostic kits suitable for use at the elevator or farm can be used successfully to identify which mycotoxins are present in suspect feedstuffs. 相似文献
18.
3970 feed samples were analysed for the fusariumtoxins deoxynivalenol and zearalenone. 979 (24.6%) of the submitted feed samples from farms with case history (swine herds: decreased feed intake and daily weight gain, vomiting, cannibalism, impaired fertility, small litter size, weakness of newborn piglets, prolonged oestrus of sows; cattle: persistence of follicular ovarian cysts, enteritis, decreased slaughter weight, feed refusal). 74% of the samples contained cereal and corn ingredients respectively or were complete diet samples from swine herds. Based on economic losses the fusariumtoxin deoxynivalenol is most important in Austrian husbandry and particularly found in maize, cornsilage, wheat and oat. 相似文献
19.
研究流食与颗粒料不同方式对断奶仔猪增重和采食量,选择杜长大三元杂种28日龄仔猪,随机区组设计,共六个区组,每窝一个区组,每个区组四头猪,分为处理组2头和对照组2头。28日龄体重:试验组7.19±0.027 Kg,对照组7.19±0.031 Kg。处理组和对照组均自由采食,自由饮水,35日龄晨称个体重,结果给予流食比使用颗粒料提高仔猪采食量33g/d(P<0.05)和日增重17.6g/d(P<0.05)。仔猪早期断乳是提高母猪生产力和规模化养猪业中的关键技术之一,现代规模养猪业已把乳猪断奶日龄提至21~28 d。 相似文献
20.
Phung LT Inoue H Nou V Lee HG Vega RA Matsunaga N Hidaka S Kuwayama H Hidari H 《Domestic animal endocrinology》2000,18(3):279-291
The effects of GHRP-2 (also named KP102), a new growth hormone-releasing peptide, on the release of growth hormone (GH) and growth performance were examined in swine. The single intravenous (i. v.) injection of GHRP-2 at doses of 2, 10, 30 and 100 microg/kg body weight (BW) to cross-bred castrated male swine stimulated GH release in a dose-dependent manner, with a return to the baseline by 120 min. The peak GH concentrations and GH areas under the response curves (GH AUCs) for 180 min after the injections of GHRP-2 were higher (P < 0.05) than those after the injection of saline. The GH responses to repeated i.v. injections of GHRP-2 (30 microg/kg BW) at 2-h intervals for 6 h were decreased after each injection. The chronic subcutaneous (s.c.) administration of GHRP-2 (30 microg/kg BW) once daily for 30 days consistently stimulated GH release. The GH AUCs for 300 min after the injections on d 1, 10 and 30 of treatment in GHRP-2-treated swine were higher than those in saline-treated swine. However, chronic administration of GHRP-2 caused a partial attenuation of GH response between d 1 and 10 of treatment. The chronic s.c. administration of GHRP-2 also increased average daily gain for the entire treatment period by 22.35% (P < 0.05) and feed efficiency (feed/gain) by 20.64% (P < 0.01) over the saline control values, but did not significantly affect daily feed intake. These results indicate that GHRP-2 stimulates GH release and enhancing growth performance in swine. 相似文献