饲粮色氨酸水平对蛋鸡生产性能及蛋品质的影响

为探讨饲粮色氨酸水平对蛋鸡生产性能和蛋品质的影响,本试验将720羽300日龄罗曼蛋鸡随机分成5组,每组3个重复,每个重复48羽.对照组饲粮为色氨酸含量为0.16%的玉米-豆粕型基础饲粮,4个试验组饲粮为通过在基础饲粮中添加色氨酸使色氨酸水平分别达到0.20%、0.24%、0.28%和0.32%的饲粮,试验期为49 d.结果表明:0.20%水平组产蛋率最高,较其他试验组及对照组分别提高了2.18%(P<0.05)、3.08%(P<0.05)、3.23%(P<0.05)、3.42%(P<0.05);各组间平均蛋重、平均日采食量和料蛋比均无显著差异(P>0.05);0.20%水平组鸡蛋蛋白高度和哈氏单位分别提高了6.69%(P<0.05)、2.20%(P<0.05);试验组血清尿素氮(SUN)含量显著减少(P<0.05),0.20%水平组血清总蛋白与白蛋白含量显著高于其他各组(P<0.05);0.20%、0.24%水平组血清中促卵泡素(FSH)含量分别比对照组提高了14.69%(P<0.05)、11.88%(P<0.05),雌二醇(E2)水平提高了20.74%(P<0.05)、15.56%(P<0.05).结果提示:色氨酸主要通过促性腺激素释放和提高饲料蛋白质利用率等途径提高蛋鸡的生产性能,蛋鸡玉米-豆粕型饲粮色氨酸适宜水平为0.20%.     

日粮色氨酸水平对蛋鸡生产性能及蛋白质代谢的影响

试验旨在研究色氨酸对罗曼蛋鸡产蛋高峰后期生产性能和蛋白质代谢的影响。选用576羽300日龄、体重相近的罗曼蛋鸡随机分成4组,每组3个重复。对照组饲喂基础日粮,试验Ⅰ~Ⅲ组分别饲喂添加400、800、1 200 g/t色氨酸的试验日粮。结果表明:试验Ⅰ组产蛋率显著高于对照组和其他处理组(P<0.05),各组间平均蛋重和料蛋比差异不显著(P>0.05);与其他组相比,试验组Ⅰ血清尿素氮显著降低(P<0.05),血清总蛋白和白蛋白含量显著提高(P<0.05);随日粮中色氨酸摄入量的增加,蛋黄中色氨酸等氨基酸沉积量增加(P>0.05)。结果提示,在蛋鸡日粮中添加适宜的色氨酸水平,有助于促进机体的蛋白质代谢,进而提高其产蛋性能。     

中草药添加剂对蛋鸡抗氧化作用及生产性能的影响

将１２０只５２周龄的海兰白蛋鸡,随机分成４组,每组３０只,Ⅰ～Ⅲ组为试验组,第Ⅳ组为对照组。Ⅰ～Ⅲ组饲喂在基础日粮中分别添加质量分数１％Ⅰ～Ⅲ号中药方剂的饲料,Ⅳ组只喂基础日粮,饲喂６周后,观察Ⅰ～Ⅲ号中药方剂对蛋鸡抗氧化作用及生产性能的影响。结果与对照组相比,试验Ⅰ、Ⅱ组鸡血清超氧化物歧化酶（ＳＯＤ）活力升高２６．２４％和１４．６３％（Ｐ〈０．０１）;全血谷胱甘肽过氧化物酶（ＧＳＨ－Ｐｘ）活力升     

饲粮色氨酸水平对黄羽肉种鸡生产性能、抗氧化功能及血清生化指标的影响

本试验旨在研究饲粮色氨酸水平对黄羽肉种鸡生产性能、抗氧化功能及血清生化指标的影响,以期探明肉种鸡饲粮的适宜色氨酸水平.试验采用单因素4水平试验设计,将360只28周龄黄羽肉种鸡随机分成4组,每组3个重复,每个重复30只.对照组饲喂基础饲粮,基础饲粮色氨酸水平为0.16％,3个试验组分别在基础饲粮中添加0.02％、0.0...     

饲粮锌添加水平对蛋鸡生产性能及组织锌含量的影响

试验选用66只18周龄商品代伊莎褐育成母鸡。随机分为3组,每组22只,对照组饲喂基础饲粮,试验1、2组在基础饲粮中分别添加60、180mg/kg的锌。研究不同锌添加水平对蛋鸡生产性能和组织器官重量及锌含量的影响。结果表明,在蛋鸡饲粮中添加锌对产蛋量、耗料量和料蛋比无显著影响(P>0.05),但破蛋率略下降,蛋重显著降低(P<0.05);除输卵管重有显著升高外(P<0.05),蛋鸡体重及其它组织器官重均无显著变化(P>0.05);肝脏中锌含量极显著提高(P<0.01);胫骨和蛋中含量显著提高(P<0.05),血清和羽毛锌有升高趋势。     

饲料铅污染对蛋鸡生产性能、蛋品质以及抗氧化性能的影响

本试验旨在研究不同剂量铅对蛋鸡生产性能、蛋品质以及血清、肝脏和肾脏中与抗氧化性能相关指标的影响。选用 ４０周龄生产性能相近的海兰褐蛋鸡 ５７６羽,随机分为 ４组：对照组、试验 １组（Ｔ１组）、试验 ２组（Ｔ２组）、试验 ３组（Ｔ３组）,每组 ４个重复,每个重复 ３６羽。对照组饲喂基础饲粮,Ｔ１、Ｔ２、Ｔ３组分别饲喂在基础饲粮中添加 １５、３０、６０ｍｇ／ｋｇ铅的试验饲粮。试验期 ８周。结果表明：１）各组间产蛋率和料蛋比均无显著差异（Ｐ＞０．０５）,１～８周 Ｔ３组平均蛋重显著低于对照组（Ｐ＜０．０５）,１～８周 Ｔ１、Ｔ２、Ｔ３组平均日采食量分别较对照组降低了３．７２％（Ｐ＜０．０５）、１．９３％（Ｐ＞０．０５）、３．６３％（Ｐ＜０．０５）。２）与对照组相比,试验组蛋白高度和哈夫单位均有降低趋势,除 Ｔ３组蛋白高度（Ｐ＜０．０５）外均差异不显著（Ｐ＞０．０５）;Ｔ３组蛋壳强度和蛋壳厚度最低,第 ４周和第 ８周时 Ｔ３组蛋壳强度分别比对照组降低了 ２１．８９％、１６．８４％（Ｐ＜０．０５）;蛋壳厚度的变化趋势与蛋壳强度一致,均随着铅添加量的增加而降低,呈现一定的剂量 －效应关系。３）与对照组相比,各试验组血清、肝脏和肾脏中谷胱甘肽过氧化物酶活性均显著降低（Ｐ＜０．０５）;丙二醛（ＭＤＡ）含量均在一定程度上升高,Ｔ３组血清和肝脏中 ＭＤＡ含量均较对照组显著上升（Ｐ＜０．０５）,各试验组肾脏中 ＭＤＡ含量均显著高于对照组（Ｐ＜０．０５）;血清、肝脏和肾脏中还原型谷胱甘肽含量和总抗氧化能力以及总超氧化物歧化酶活性均呈现降低趋势。综上所述,饲料中铅污染可以导致蛋品质降低,诱导脂质过氧化作用,降低蛋鸡抗氧化能力。     

日粮铜水平对蛋鸡生产性能的影响

选择体重及产蛋率相近的海兰褐32周龄蛋鸡160只,随机分成5个处理组,每组4个重复,每组重复8只,以玉米-豆粨-棉籽粨型日粮为基础日粮,铜的添加水平分别为0mg/kg,4mg/kg,8mg/kg,15mg/kg,60mg/kg,研究日粮中不同铜水平对蛋鸡生产性能的影响。实验结果表明：所有添加铜的产蛋率均高于对照组,料蛋比低于对照组;添加4mg/kg,8mg/kg铜组产蛋率与对照组差异显著（P〈0.05）;添加4mg/kg铜组产蛋率最高;添加8mg/kg组料蛋比最小,耗料最少;平均蛋重各处理组与对照组无明显差异（P〉0.05）。     

饲粮添加虾青素对69～74周龄蛋鸡生产性能、蛋品质、抗氧化能力、生殖激素和卵泡数量的影响

本试验旨在研究饲粮添加不同水平虾青素对69～74周龄蛋鸡生产性能、蛋品质、抗氧化能力、生殖激素和卵泡数量的影响。采用单因素试验设计,选取450只体重[(2.02±0.18) kg]相近、体质健康的68周龄海兰褐产蛋鸡,按产蛋率无显著差异(P>0.05)原则分为5个组,每组6个重复,每个重复15只鸡。对照组饲喂基础饲粮,试验组饲喂在基础饲粮中分别添加15、30、45和60 mg/kg虾青素的饲粮。试验预试期1周,正试期6周。结果表明：1)与对照组相比,饲粮添加不同水平虾青素对蛋鸡生产性能无显著影响(P>0.05)。2)与对照组相比,饲粮添加不同水平虾青素可线性显著提高蛋鸡卵巢总超氧化物歧化酶活性(P<0.05),并显著降低卵巢丙二醛含量(P<0.05)。3)与对照组相比,饲粮添加不同水平虾青素可显著提高蛋鸡血清卵泡刺激素、促黄体生成素和孕酮含量(P<0.05)。4)与对照组相比,饲粮添加不同水平虾青素可显著提高蛋鸡卵巢中初级卵泡、次级卵泡和等级前卵泡数量(P<0.05),显著降低次级卵泡闭锁率(P<0.05);卵巢中卵泡数量与虾青素添加水平呈线性...     

不同水平脱壳白高粱对蛋鸡生产性能、蛋品质及血清抗氧化的影响

试验研究不同比例脱壳白高粱等比例替代玉米对蛋鸡生产性能、蛋品质、营养物质表观消化率及血清抗氧化指标的影响。选取720只蛋鸡,随机分为5组,每组6个重复,每个重复24只鸡。对照组（A组）为基础日粮,各试验组（B组、C组、D组、E组）分别使用5%、10%、15%、20%脱壳白高粱等比例替代基础日粮中的玉米。试验期8周。结果显示：与对照组相比,各试验组蛋鸡的产蛋率、平均日采食量、平均蛋重及料蛋比差异均不显著（P>0.05）;D组、E组鸡蛋的蛋黄颜色分别降低了9.93%、16.97%(P<0.05)。各组蛋鸡钙、磷及粗蛋白表观消化率差异均不显著（P>0.05）。各组蛋鸡血清抗氧化指标差异均不显著（P>0.05）。与对照组相比,C组、D组、E组饲料单价分别比对照组提高了0.36%、0.73%、1.47%,B组、C组利润分别提高了3.42%、3.59%,D组、E组利润分别降低了7.96%、9.62%,以C组利润最佳。研究表明,采用脱壳白高粱替代日粮中5%玉米对蛋鸡的生产性能效果较好。     

Effects of dietary L-threonine levels on antioxidant capacity,digestive enzyme activities,and antibody production of Xinyang green-shell laying hens

Xinyang green-shell laying hens (n = 720), 32 wk of age were allocated to 5 dietary treatments groups, each of which included 6 replicates of 24 hens. The control group was given a basal corn-peanut-soybean meal diet containing 0.47% L-threonine (L-Thr). L-Thr levels of the experimental groups were 0.57, 0.67, 0.77, and 0.87%, respectively. The trial lasted 10 wk. Serum concentrations of total superoxide dismutases (T-SOD) and superoxide dismutases (SOD) were maximized at 0.67% L-Thr group. The 0.57% L-Thr group had the highest serum total antioxidative capacity (T-AOC), while the 0.67% L-Thr group had the lowest serum malondialdehyde (MDA) concentration. Hens fed 0.67% L-Thr of the diet resulted in the highest SOD and T-AOC levels in the liver. The activity of amylase and lipase in the jejunum was maximized at 0.77% L-Thr level. Hens fed 0.77% L-Thr in the diet resulted in the highest IgM and IgG levels in the jejunum. In conclusion, we suggest that a L-Thr level above 0.67% may have had an antioxidant capacity and positive effect on digestive enzyme activities and antibody production in the jejunum of Xinyang green-shell laying hens.     

Effects of dietary supplementation of resveratrol on performance,egg quality,yolk cholesterol and antioxidant enzyme activity of laying hens

1. This experiment was conducted to evaluate the effects of dietary supplementation of resveratrol on laying performance, egg quality, egg yolk cholesterol and antioxidant enzyme activities of laying hens.

2. A total of 360 Beijing PINK-1 laying hens (60 weeks old) were randomly distributed among five dietary treatments, each of which included 6 replicates of 12 hens. Dietary treatments were basal diet supplemented with 0 (control), 0.5, 1.0, 2.0 and 4.0 g/kg diet resveratrol. The study lasted for 9 weeks including 1 week of adaptation and 8 weeks of the main experimental period.

3. The results indicated that dietary resveratrol significantly improved feed conversion ratios during 5–8 weeks and 1–8 weeks of the trial. Increasing dietary concentrations of the resveratrol linearly improved Haugh unit and albumen height of eggs.

4. The content of total cholesterol (TC), total triglyceride (TG), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C) in serum and cholesterol in yolk was significantly decreased by dietary resveratrol, and there were significant linear correlations between these indexes and resveratrol supplemental levels.

5. Dietary resveratrol supplementation significantly improved serum Glutathione peroxidase (GSH-Px) enzyme activity and decreased serum malondialdehyde (MDA) content in groups with 2.0 and 4.0 g/kg resveratrol as compared to the control, respectively. However, supplementation of resveratrol did not affect the activity of serum superoxide dismutase (SOD).

6. It is concluded that resveratrol supplementation has a positive effect on performance, lipid-related traits and antioxidant activity of laying hens.     

Alleviation of hysteria in laying hens with dietary tryptophan.

A commercial layer breeder flock that was suffering from hysteria was fed a diet containing 5 grams tryptophan/kg for six days. The incidence of episodes of hysteria declined from five times/hour on day 0 to once/hour on day 6 and none on day 8. Feed consumption increased from 107 g to 145 g/hen/day and egg production increased 23% during the six day feeding period. The tryptophan concentration in plasma doubled (from 95.6 to 188.2 mumol/mL). Plasma phenylalanine and tyrosine also increased. Birds that were not in lay, by postmortem examination, had significantly higher plasma valine concentrations (476.4 vs 372.7 mumol/mL). Tryptophan, serotonin and related metabolites increased in both the hypothalamic region and the remainder of the brain following tryptophan feeding, and subsequently declined. High levels of dietary tryptophan may be useful in alleviating hysteria in poultry.     

Effects of dietary boron supplementation on laying hens

1. The effects of dietary boron on egg production and on the ultimate shear force, stress, and fracture energy of the tibia, femur, humerus, and radius from White Leghorn laying hens were investigated.

2. The shear force, stress, and fracture energy of the bones were not affected by increasing dietary concentrations of boron.

3. Egg production, food consumption and body weight were suppressed at a dietary boron concentration of 400 mg/kg.

4. Boron concentrations increased significantly in all tissue samples tested in birds given 400 mg/kg dietary boron.     

日粮添加柠檬酸对蛋鸡生产性能的影响

采用六处理三重复单因子试验研究0%、0.05%、0.15%、0.25%、0.35%和0.55%柠檬酸添加水平对蛋鸡生产性能的影响,并分析各柠檬酸添加水平对蛋鸡高温期间生产性能的影响。结果表明:0.05%~0.55%柠檬酸添加量显著降低整个试验期和试验高温期的软、破蛋率(P<0.05),对其它生产指标无显著影响(P>0.05)。     

Effects of age on the tryptophan requirement of laying hens

1. White Leghorn pullets which had been used for an assay of tryptophan requirement between 32 and 40 weeks of age were used for similar determinations between 63 and 73 and, after a moult, from 97 to 106 weeks of age.

2. A tryptophan‐limiting protein mixture was used and by dilution seven dietary protein contents were produced, supplying from 0.84 to 1–92 g tryptophan/kg diet. The diet of lowest protein content was also sup‐lemented with free tryptophan. These diets were fed in experiments using 24 groups of 72 pullets at 63 to 73 weeks and 45 groups of 21 hens at 97 to 106 weeks.

3. The relationship between egg output and tryptophan intake was the same in moulted hens as in young pullets, but pullets of 63 to 73 weeks of age yielded a different response curve; more tryptophan being needed for a given egg output.

4. It is concluded that tryptophan required, per day, does not decrease during the first laying year, despite a decrease in rate of egg output.     

能量水平对粉壳蛋鸡生产性能及蛋品质量的影响

为研究不同能量水平对产蛋性能和蛋品质量的影响,试验选用504只194日龄罗曼粉蛋鸡,试验共设3个处理,每个处理5个重复,每个重复33～35只,分别饲喂三个能量水平(10.88、11.09、11.30 MJ/kg)的日粮。试验共进行30 d。试验结果表明,各处理组在采食量、产蛋率、平均蛋重、料蛋比、蛋壳强度和哈夫单位等方面差异不显著;表明能量水平在50～100 kcal/kg范围内波动,对蛋鸡生产性能和蛋品质量未产生显著影响。     

Effect of dietary fibre on the performance of laying hens

1. In tests to determine whether gizzard weight could be influenced by dietary fibre concentrations, caged layers were fed on diets containing 15, 30 or 60 g pine shavings/kg diet.

2. As dietary fibre content increased, gizzard weight increased, but there was no effect on body weight, hen‐day production, egg weight, efficiency of food conversion, mortality, percentage of liver ether extract or egg shell breaking strength. Percentage of body ether extract tended to be lower when pine shavings were fed.