植物甾醇对生长猪生产性能影响的研究初探

日粮中分别添加0、15和30mg/kg的植物甾醇,进行饲养试验,研究植物甾醇对生长猪生产性能的影响。结果表明,与对照组相比较,添加15和30mg/kg植物甾醇使平均日增重分别提高12.16%和7.14%;饲料转化率分别提高2.56%和7.10%。经济效益分析表明,15和30mg/kg试验组的利润分别比对照组提高24.38%和25.97%。植物甾醇在15和30mg/kg的添加范围内均可有效改善生长猪的生产性能。     

干白酒糟对生长肥育猪生产性能的影响

试验选用97日龄体重相近、健康度良好的杜长大三元杂生长肥育猪200头,随机分为4个处理组,每组5个重复,每个重复10头猪(公母各半)。对照组饲喂玉米-豆粕型基础日粮,3个试验组分别为在对照组日粮基础上使用5%、10%、15%干白酒糟,并通过氨基酸和油脂等添加量的变化进行日粮营养成分平衡,以考察干白酒糟对生长肥育猪生产性能的影响。结果表明,与对照组相比,生长肥育猪日粮添加5%干白酒糟后,生长肥育猪生产性能与对照组相当。但干白酒糟添加量达到10%或以上时,生长肥育猪生产性能有下降的趋势,且呈现出明显的剂量效应。综上,生长肥育猪日粮中,干白酒糟的用量需控制在10%以内。     

复合酶制剂对生长猪的生产性能和养分消化性的影响

选择３５ｄ龄断奶体重约９ｋｇ的长大二元杂交仔猪２４头,随机分成２组,研究添加复合酶制剂以生长猪生产性能的影响。选择体重３５￣４０ｋｇ６头阉公猪采用全收粪法进行消化试验,研究复合酶制剂对日粮养分表现消化率的影响。结果表明,添加酶制剂能显著提高生长猪地生产性能和日粮养分的表现消化率,与对照组组相比,日增重提高８．２９（Ｐ〈０．０５）。饲料转化率提高８．８９％（Ｐ〈０．０５）,粗纤维表现消化率提高３６．     

益生素对生长猪生产性能和免疫功能的影响

研究在生长猪日粮中添加益生素替代抗生素的可行性以及最佳用量.在对照组基础日粮中添加抗生素,在试验Ⅰ组、Ⅱ组和Ⅲ组日粮中分别添加0.1％、0.2％和0.4％益生素替代抗生素.结果表明:(1)与对照组相比,试验Ⅰ组、Ⅱ组和Ⅲ组平均日增重分别提高-9.80％ (P＜0.05)、0.81％ (P＞0.05)和1.35％ (P＞...     

凹凸棒石黏土对生长育肥猪生产性能、金属含量及肉品质的影响

研究凹土原土及热改性凹土对生长育肥猪生产性能、金属含量和肉品质的影响。选用体重约47kg健康\"杜×长×大\"三元杂交的生长育肥猪60头,随机分为3组,每组4个重复。对照组饲喂基础日粮,试验组饲喂在基础日粮中添加2%凹土原土、2%热改性凹土的试验日粮。结果表明:1)凹土原土和热改性凹土对生长育肥猪生产性能无显著影响(P0.05);2)凹土原土和热改性凹土降低血液中As、Pb、Cr含量和腿肌中Cr的含量(P0.05),热改性凹土显著提高血液中Mg含量(P0.05);3)凹土原土降低眼肌MDA(P0.05),凹土原土和热改性凹土降低眼肌中T-AOC的活性(P0.05);4)凹土原土提高眼肌p H45 min、a*45 min(P0.05),降低L*45 min、b*24 h和压力损失(P0.05)。添加凹土原土和热改性凹土能降低重金属在动物机体中的沉积、提高抗氧化能力进而改善肉品质,热改性凹土效果优于原土。     

植酸酶对生长肥育猪生产性能及养分消化率影响的研究

选用120头体质健康的三元杂交(杜×长×大)生长猪,平均体重为(34.7±5.1)kg,随机分为5组,每组4个重复,每个重复6头。试验结果表明:①400U/kg的植酸酶替代50%的磷酸氢钙组(试验1组)对生产性能的改善效果最佳,可使日增重提高15.6%,料重比改善11.3%;其次为600U/kg的植酸酶替代75%的磷酸氢钙组(试验4组)。②植酸酶替代磷酸氢钙对猪粗蛋白质、能量及氨基酸消化率影响不大。③所有的植酸酶组均明显提高了磷的消化率。试验1组与对照组相比使干物质消化率提高了5.86%,粗灰分、钙及磷的消化率亦分别提高了13.9%、13.8%和20.1%。     

饲喂南方高油玉米对生长肥育猪生产性能的影响

通过饲养试验探讨南方高油玉米对生长肥育猪的生产性能的影响,进一步评价高油玉米用作猪饲料的效果及饲用价值。结果表明: ( 1 )生长期,A组和C组日增重显著高于B组和D组(P<0.05);日采食量和饲料利用率差异不显著(P>0. 05),但D组饲料利用率要优于其它各组。( 2 )肥育期和全期,日均增重、日均采食量和饲料利用率均无显著性差异(P>0. 05)。由此可见,高油玉米营养成分间比例不平衡,在没有提高饲料中优质蛋白饲料和氨基酸配比的条件下,饲喂高油玉米并不能改善生长肥育猪的生产性能。     

高铜改善猪生产性能和促生长机理的研究进展

概述了高铜对改善猪生产性能的效果,促生长的作用机理。在饲料中添加铜６２．５￣２５０ｍｇ／ｋｇ,可显著促进仔猪生产,降低单位增重饲料消耗,但随着仔猪日龄的增大铜促生长作用减弱。铜对猪的促生长作用很可能是系统性的,而不只限于胃肠道抗微生物作用;提示养猪生产中要研制、开发和应用高效的新型有机铜源,以最大地发挥铜对猪的促生长效应,同时减少铜排出对环境的污染。     

无抗日粮中添加灭活乳酸菌对黄羽肉鸡生长和屠宰性能的影响

研究无抗日粮中添加灭活乳酸菌对黄羽肉鸡生长和屠宰性能的影响.将1800只1日龄黄羽肉鸡随机分为4个组(正对照、负对照、负对照+300 g/t灭活乳酸菌、负对照+500 g/t灭活乳酸菌),每组6个重复,每个重复75只鸡,进行为期63 d的试验.结果表明,在无抗日粮基础上添加300～500 g/t灭活乳酸菌能显著(P<0...     

发酵饲料对生长肥育猪脂肪品质的影响

采用玉米-豆粕型基础日粮,研究日粮添加无抗生素微生物发酵饲料、抗生素对猪肉肌内和皮下脂肪组织品质的影响。对照组饲喂基础日粮,抗生素组在基础日粮基础上添加15%金霉素,发酵料组在基础日粮基础上添加15%～20%的发酵饲料;试验在25～60kg和60～100kg两个阶段进行。结果表明:日粮添加发酵饲料可显著提高肌内脂肪的含量,降低亚油酸、总多不饱和脂肪酸的含量和n-6/n-3的值,增加α-亚麻酸和总单不饱和脂肪酸的含量,降低硫代巴比妥酸反应物值。     

乳酸菌发酵面包工艺研究

以面包专用粉为主要原料,添加乳酸菌、酵母、面包改良剂、白糖等辅料,采用二次发酵工艺生产面包。以感官评价为指标,通过单因素及正交试验,确定最佳的工艺条件和参数为:白砂糖15%、酵母2%、乳酸菌2%、发酵时间4 h。该工艺下制作的面包内部组织柔软细腻,纹理结构好,发酵香味浓郁,且有柔和的乳酸味,其品质优于普通面包。     

发酵牛肉香肠菌种的筛选及工艺优化

试验先对几种乳酸菌进行筛选试验,找到适合牛肉发酵香肠的菌种,然后对利用这些菌种制作发酵牛肉香肠的工艺进行优化。结果表明,经过筛选发现清酒乳杆菌、发酵乳杆菌和藤黄微球菌适合生产牛肉发酵香肠,最佳工艺条件为发酵剂的添加量为104cfu/100g、作用温度为30℃、作用时间为60h。     

发酵肉制品中益生性乳酸菌的快速筛选

利用一种快速的分离筛选法,即利用pH 2.5和1% 胆盐的MRS液体培养基,对自然发酵肉制品中耐高酸耐胆盐的乳杆菌进行富集,从中分离纯化得到77株乳杆菌.通过对分离菌株进行耐高酸(pH值2.5)、0.3%胆盐的生长的进一步测定,筛选出了21株耐酸及胆汁酸盐菌株,最后运用API 50CHL对筛选菌株进行了鉴定.这些菌株可活体摄入人体肠道,发挥其益生性,为益生性发酵剂开发奠定了基础.     

Body composition and feed intake of young pigs postweaning

Thirty-five female Large White pigs were weaned at 14 days of age, penned individually, given a single diet and slaughtered serially at 25, 40, 55 and 70 days of age. A control group was fed to appetite throughout while three groups were subjected to feed restriction at various ages postweaning. For the periods 25 to 40, 40 to 55, 55 to 70 days of age pigs fed to appetite gained 321 (±19.9), 532 (±35.4) and 601 (±35.5) g liveweight day^?1. Pigs restricted between 25 and 55 days, followed by refeeding from 55 to 70 days, gained 192 (±14.0), 169 (±44.8) and 508 (±81.0) g liveweight day^?1; pigs restricted between 40 and 55 days, followed by refeeding from 55 to 70 days, gained 425 (±42.8), 409 (±49.6) and 480 (±70.1) g liveweight day^?1. A group given 200 g feed day^?1 gained 42 (±4.2) g liveweight daily between 25 and 70 days. Refed groups did not differ significantly from controls in their feed intakes for the period 55 to 70 days, either in absolute intakes or in feed intake kg^?1 mean liveweight. Refed pigs grew no faster, and made no greater protein gains than controls of equivalent weight; however, lipid gains were elevated.     

发酵牛乳酒的研制

用乳酸菌、酵母菌酵生产牛乳酒。由对比实验得出乳酸菌和酵母菌单独发酵优于混合发酵。通过正交实验确定牛乳酒的最佳发酵工艺条件为：原料乳加糖8%（质量分类），酵母菌（质量分数为8%）在30℃发酵22h，然后再添加乳酸菌（质量分数5%）在40℃下培养2h。成品指标：酒精度0.60%,乳酸度1.05%，口感细腻、滑润，酸度适中，无脂肪及上清液析出，凝乳状态良好，无渣状，乳白色不透明，有较浓厚的醇香味。     

清真发酵牛肉香肠生产工艺的研究

以干酪乳杆菌和肉糖葡萄球菌为发酵剂生产牛肉发酵香肠,并对该工艺进行了研究.结果表明,最佳工艺为:接种量为1.5·107,葡萄糖酸-δ-内酯(GDL)的添加量为0.6%,葡萄糖(GLC)的添加量为0.25%.     

酵母菌乳酸菌联合发酵荔枝果汁开发低醇饮品的研究

采用单因素试验和正交试验研究了酵母菌和乳酸菌联合发酵荔枝果汁开发低醇荔枝保健饮品的工艺条件。最优发酵工艺条件为:发酵时间为20h,乳酸菌接种量为1.5%,发酵温度为32℃,pH值为4.0,酵母菌接种量为1%。最优工艺条件下进行10L中试发酵,所得产品各项检测指标均较好。     

乳酸菌发酵香肠中风味物质变化的研究

研究了乳酸菌发酵香肠中风味物质的变化,结果表明:发酵香肠中的主要风味物质乳酸、游离氨基酸和游离脂肪酸含量在发酵过程中都有明显增加。添加纯菌种发酵24 h后,乳酸、游离氨基酸和游离脂肪酸含量分别达到0.94%、4.38%(干基)和1.40%(干基),鲜味氨基酸谷氨酸和天冬氨酸分别是发酵前的15.3倍和11.3倍。在成熟期,各种风味物质仍保持平缓增势。     

Effect of expander conditioning and/or pelleting of a diet on the ileal digestibility of nutrients and on feed intake after choice feeding of pigs

A pig diet, processed in three different ways, was evaluated in an ileal digestibility trial. The complete diet contained mainly pea, tapioca and soybean meal and was processed by steam-pelleting (SP), high-shear conditioning (expander treatment; E) and expander-pelleting (EP), respectively. Expander-pelleting clearly improved the physical quality of pellets in terms of hardness and durability as compared to steam-pelleting. The apparent ileal digestibility of dietary nitrogen, dry matter, organic matter and crude fat determined with piglets in the weight range of 20–25 kg was not affected by the technological treatments under investigation. Only the crude fibre digestibility was significantly improved by single expander conditioning (P<0·05); the absolute level of 7·6% however was of low significance. Under the conditions of the present study, high shear conditioning (expander treatment) prior to pelleting showed no favourable effects on the apparent ileal digestibility of nutrients. Feed intake of the diets, offered in a choice feeding design to piglets of about 27 kg liveweight showed a large variation between piglets but in favour of the SP and E diet. Since diet hardness is related directly to the animal feed intake, maximisation of diet durability of expanded or pelleted diets should be achieved in relation to an optimisation of diet hardness and nutrient utilisation in piglets. © 1998 SCI.     

The effect of expander processing and pelleting on the nutritive value of feed for growing and finishing pigs

Two experiments were conducted to determine the effect of pelleting and/or expander processing on the nutritive value of feed when fed to growing and finishing pigs. Experiment 1 determined the effects of pelleting and/or expander processing on the apparent nutrient digestibility of the diets. In experiment 2, productive performance and carcass characteristics were determined in group‐fed pigs (n = 312) offered identical diets in raw pellet form (T1), expander‐processed pellet form (T2), raw meal form (T3) and expander‐processed meal form (T4). The expanded diets were expander processed at 105 °C for 5 s at 35 bar pressure. The pellet diets were steam pelleted at 85 °C into 3.0 mm pellets. Pelleting of the diets increased organic matter (P < 0.05), protein (P < 0.01), energy (P < 0.01) and ash (P < 0.01) digestibility as well as the digestible energy (DE) content of the diets (P < 0.01). Expander processing had no effect on the organic matter, protein and energy digestibility of the diets. There was a significant interaction (P < 0.05) between pelleting of the diet and expander processing in DE content of the diets. Expansion had no effect on the DE content of the pelleted diets; however, expansion increased the DE content of the meal diets (P < 0.05). In experiment 2 there was a significant interaction between the physical form of the diet and expansion in feed intake during the grower and finisher period (P < 0.01). Expander processing had no effect on feed intake in the pelleted diets; however, expansion decreased feed intake of the meal diets (P < 0.001). Both pelleting and expansion of the diets decreased growth rate during the grower and finisher period (P < 0.05). Pelleting of the diets improved feed conversion ratio (FCR) during the grower and finisher period (P < 0.05), while expander processing had no effect on FCR. © 2000 Society of Chemical Industry