Effects of karaya saponin and Rhodobacter capsulatus on yolk cholesterol in laying hens

1. It has been reported that karaya saponin and Rhodobacter capsulatus individually have hypocholesterolaemic activity in laying hens. This study focuses on the effect of adding karaya saponin with R. capsulatus to hen's diet with regard to serum and egg yolk cholesterol and triglycerides.

2. A total of 56 Boris Brown laying hens were divided into 7 groups at 20 weeks of age. Combinations of 25, 50, 75 mg kg^?1 karaya saponin and R. capsulatus 200 and 400 mg kg^?1 were used as treatment groups.

3. After 8 weeks of supplementation, the effects of all the combinations of karaya saponin and R. capsulatus on serum and egg yolk cholesterol, triglycerides, and high-density lipoprotein (HDL)-cholesterol were greater than either karaya saponin or R. capsulatus alone. The combination of karaya saponin 50 mg kg^?1+ R. capsulatus 400 mg kg^?1 exhibited the greatest reduction of serum (32?5%) and yolk (22?5%) cholesterol and the greatest increase of faecal, liver bile acids and yolk fatty acid (oleic, linoleic and linolenic) concentrations. In addition, egg production and yolk colour were significantly improved by the combined use of karaya saponin and R. capsulatus supplementation.

4. Therefore, the dietary supplementation of karaya saponin and R. capsulatus may lead to the production of a low-cholesterol egg, with production performance maintained at a standard level.     

Effect of dietary karaya saponin on serum and egg yolk cholesterol in laying hens

1. The objective of the study was to investigate the effect of dietary karaya saponin on cholesterol deposition in laying hens. 2. A total of 40 Boris Brown hens were randomly assigned at 20 weeks of age to 4 treatment groups and fed on diets supplemented with 0 (control), 25, 50 or 75 mg/kg karaya saponin for an 8-week experimental period. 3. After 8 weeks of dietary supplementation, karaya-saponin-treated groups had significantly lower serum cholesterol (23·0%) and triglycerides but increased high density lipoproteins cholesterol concentration than controls, irrespective of karaya saponin content in the diet. Egg yolk cholesterol and triglycerides were also significantly reduced by dietary karaya saponin. Hepatic cholesterol and triglycerides were significantly reduced by karaya saponin but bile acids concentration in the faeces and liver were significantly increased by karaya saponin. The concentrations of oleic, linoleic and linolenic acids in the yolk were greater in hens receiving karaya saponin than in controls. Karaya saponin significantly increased egg production, feed efficiency and yolk colour compared with controls. Karaya saponin tended to increase egg weight, feed consumption, Haugh units, albumen weight and yolk index. 4. In conclusion, karaya saponin is a potential agent for reducing yolk cholesterol concentration together with an overall increase of production performance and improvement in egg quality.     

槲皮素对蛋黄卵磷脂含量的影响

试验将29周龄海赛蛋鸡240只随机分4组,每组6个重复,每个重复10只鸡,对照组饲喂基础饲粮,试验组在基础饲粮基础上分别添加0.02%、0.04%和0.06%槲皮素,预试期1周,试验共8周。旨在研究饲粮中添加槲皮素对蛋黄卵磷脂含量的影响。结果表明,与对照组相比,0.04%槲皮素组蛋黄卵磷脂与粗脂肪含量分别显著提高19.86%和5.81%(P<0.05);0.02%槲皮素组血清游离脂肪酸(FFA)含量显著升高(P<0.05);0.04%槲皮素组血清极低密度脂蛋白胆固醇(VLDL-C)、载脂蛋白B(apo-B)、载脂蛋白A1(apo-A1)含量均显著升高(P<0.05);0.04%槲皮素组血清雌二醇(E2)、胰岛素(INS)含量与0.02%槲皮素组胰岛素(INS)含量均显著升高(P<0.05)。由此可见,一定剂量槲皮素能通过改善蛋鸡内分泌活动,提高血脂水平来提高蛋黄卵磷脂含量。     

槲皮素对蛋鸡胆固醇代谢的影响

采用单因素试验设计,选体重和产蛋率相近的29周龄蛋鸡240只,随机分为4组,每组6个重复,每重复10只鸡。在玉米-豆粕型饲粮基础上添加0、0.02%、0.04%和0.06%槲皮素,进行8周的饲养试验。研究槲皮素对蛋鸡的血脂、鸡蛋胆固醇和甘油三酯、肝脏胆固醇和甘油三酯、血清雌激素和胰岛素的影响。结果表明,与对照组相比,0.04%槲皮素可显著降低血清甘油三酯含量(P<0.05);0.02%、0.04%槲皮素极显著降低蛋黄胆固醇含量(P<0.01),三个剂量槲皮素均可显著降低肝脏胆固醇含量(P<0.05),但对肝脏和蛋黄甘油三酯含量无显著影响(P>0.05);0.04%槲皮素可显著提高血清胰岛素和雌二醇含量(P<0.05)。由此可见,一定剂量槲皮素能降低鸡蛋中胆固醇含量,最适添加量为0.04%。     

Effects of inulin on performance, egg quality, gut microflora and serum and yolk cholesterol in laying hens

1. The present study was conducted to investigate the effects of inulin on laying hens. A total of 360 Brown Nick laying hens were divided randomly into 6 groups of 60 with 6 replicates of 10 hens and fed on diets containing 0 (control), 0·1, 0·5, 1·0, 1·5 or 2·0% inulin during the 4-week trial. 2. Dietary supplementation of inulin reduced cholesterol concentration (mg/g yolk) and content (mg/egg) in eggs. Cholesterol content in eggs decreased linearly with increasing levels of dietary inulin level. 3. Supplementation of inulin in diets decreased coliform bacteria counts and pH in the caecum. The lowest coliform bacteria counts (6·30 ± 0·03 log10 cfu/g) and pH (6·47 ± 0·01) were obtained in the 2·0% inulin group, the two indices decreasing by 21·6% and 3·0% respectively, compared with the control group. Coliform bacteria count and pH were changed linearly in accordance with increasing levels of dietary inulin level. Caecal Bifidobacteria counts were increased in the 2·0%-inulin group. 4. Inulin supplementation of layer diets did not appear to have any adverse effects on laying rate, egg weight, feed intake, feed conversion efficiency, cracked-egg rate, eggshell thickness or Haugh unit compared with the control laying hens. 5. Therefore, dietary supplementation with inulin may lead to the development of low-cholesterol chicken eggs as demanded by health-conscious consumers.     

Diagnostic utility of egg yolk for the detection of avian metapneumovirus antibodies in laying hens

Surveillance and diagnosis of avian metapneumovirus (AMPV) infection typically involve measurement of serum antibodies. In the current study, eggs instead of serum samples were used for the detection of AMPV antibodies in egg-laying chicken hens by enzyme-linked immunosorbent assay (ELISA). AMPV-free commercial layer hens were experimentally challenged with AMPV strain SC1509 through intravenous or oculonasal administration. Antibody levels were determined by ELISA. AMPV antibodies were detected in egg yolks from challenged hens by 7 days postinoculation (dpi), with the peak titer at 16 dpi. Antibody levels in eggs laid at 28 dpi correlated well (r = 0.93) with sera taken 28 dpi from the same hens. In a field trial of the yolk ELISA, six broiler breeder farms were surveyed, and all tested positive for AMPV antibodies in hen eggs, although positivity varied from farm to farm. Abnormal discolored eggs collected from outbreak farms had significantly higher titers of AMPV yolk antibodies than normal eggs from the same farm, unlike clinically healthy farms, where normal and abnormal eggs had similar antibody titers. These results indicate that diagnosis of AMPV infection by yolk ELISA to detect anti-AMPV antibodies may be a suitable alternative to serologic testing.     

Effects of zinc and vitamin A supplements on plasma levels of thyroid hormones, cholesterol, glucose and egg yolk cholesterol of laying hens

The effects of zinc and vitamin A supplementation to the diet on some blood metabolites were evaluated in Hisex brown laying hens from 56 weeks to 68 weeks of age. A total of 130 birds were divided into two main groups according to vitamin A treatment (0 and 3.44 mg retinyl acetate kg(-1) feed, respectively), each consisting of 65 hens. Hens in both of the main groups were then divided into five zinc treatment groups (0, 25, 50, 100 and 200 mg zinc kg diet(-1) respectively) of 13 hens each. It was observed that plasma T4, T3 and total cholesterol levels were affected by only zinc supplementation. While 100 and 200 mg Zn kg(-1) decreased plasma T4 level compared to control value, plasma T3 level was reduced by 100 mg Zn kg(-1) compared to groups fed less Zn. Adding 50 and 200 mg Zn kg(-1) to the diet increased plasma total cholesterol level in the birds compared to other groups. Vitamin A, zinc, and their interaction did not influence the concentration of plasma high-density lipoprotein (HDL)-cholesterol, glucose and egg yolk cholesterol in laying hens.     

碱式氯化锌对绿壳蛋鸡产蛋性能和蛋黄中锌沉积量的影响

本试验旨在研究碱式氯化锌对蛋鸡生产性能、蛋品质及蛋黄中锌沉积量的影响。选取240羽东乡黑羽绿壳蛋鸡随机分成4组,每组6个重复,每个重复10羽。A组为对照组,饲喂基础日粮,B、C、D组为试验组,分别在基础日粮中添加80、120 mg/kg和160 mg/kg碱式氯化锌。预试期7 d、正式期28 d。结果表明,与对照组相比,从第二周开始,各试验组产蛋率不同程度提高,各试验组料蛋比有所下降;试验各组间蛋壳厚度、蛋形指数、蛋黄色泽和哈氏单位差异均不显著;B组和D组蛋黄中锌含量显著高于对照组(P<0.05),分别较对照组提高17.39%和27.74%,C组蛋黄中锌含量极显著高于对照组(P<0.01),较对照组提高32.29%。由此可见,日粮中添加碱式氯化锌能改善蛋鸡生产性能,提高鸡蛋中锌的沉积量,综合考虑,120 mg/kg为适宜添加量。     

不同锌源对绿壳蛋鸡产蛋性能和蛋黄锌含量的影响

选取180只东乡黑羽绿壳蛋鸡随机分成3组,每组6个重复,每个重复10只。A组为对照组,饲喂基础日粮,B组、C组分别在基础日粮基础上添加120 mg/kg的羟基蛋氨酸锌和碱式氯化锌(按锌含量计)。预试期7 d、正式期28 d。结果表明,与对照组相比,日粮中添加羟基蛋氨酸锌可显著提高蛋鸡产蛋率(P<0.05);碱式氯化锌可极显著提高蛋鸡产蛋率(P<0.01),显著降低料蛋比(P<0.05);试验各组的蛋壳厚度、蛋黄指数、蛋形指数、哈氏单位差异均不显著;两种锌源均可极显著提高蛋黄中锌含量,试验第28天时,分别较对照组提高32.8%和32.3%(P<0.01)。由此可见,日粮中添加羟基蛋氨酸锌和碱式氯化锌均能改善蛋鸡生产性能,提高鸡蛋中锌含量,综合比较,添加碱式氯化锌效果更好。     

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.     

Effect of sweet green pepper on yolk color and performance of laying hens

An experiment was conducted to evaluate the effects of sweet green pepper (SGP) on the performance and egg quality of commercial laying hens. A total of 144 Hy Line W36 egg layers were randomly assigned to 4 treatments with 9 replicate groups of 4 hens each. Treatments consisted of the following diets: 1) basal diet (BD), 2) BD + 75 ppm SGP, 3) BD + 125 ppm SGP, 4) BD + 225 ppm SGP. The diets contained 2,730 kcal/kg metabolizable energy and 15.5% crude protein. Egg production and egg quality were monitored for 16 weeks. Feed intake, hen-day egg production, egg mass, and feed conversion per dozen were not significantly affected by the addition of SGP to the diets. The addition of 225 ppm of SGP decreased egg weight. Specific gravity, albumen height, Haugh unit, yolk weight, albumen weight, albumen percentage, and yolk yellowness (b*) were not significantly affected by the addition of SGP. The addition of SGP to the diets increased yolk percentage, yolk color using a Roche fan, and yolk redness (a*). Based on these data, SGP was shown to be a useful feed ingredient for laying hens; it can be included in diets without negative effects on performance and egg quality. However, owing to the depression of egg weight with the inclusion of SGP, it may be of interest to producers and industry to control egg size in old layers and possibly improve shell quality. The addition of SGP to the diets impacted yolk color and may be useful in specialty markets.     

蛋鸡产蛋期饲养技术要点

蛋鸡词养周期较长,一般可分为育雏期、育成期、产蛋期等阶段,其中产蛋期最长,也是蛋鸡养殖盈利的重要时期,现代高产蛋鸡产蛋期鸡只身体负荷大,如果词养技术跟不上会严重影响鸡只健康状况和生产性能。从现实看,蛋鸡从业者饲养管理水平参差不齐,即便是大型规模养殖场,精细化饲养也做得不到位,造成鸡只体况不佳、鸡蛋质量差、产蛋率低等问题,小、散户更为明显。本文结合生产实际,重点从词养、营养供给方面对高产蛋鸡产蛋期词养技术进行了总结归纳。     

Effects of dietary copper on production and egg cholesterol content in laying hens

1. This experiment was carried out to determine the effects of diets supplemented with different amounts of copper on egg production, food intake, food conversion ratio, egg weight, damaged egg ratio, specific gravity, mortality and cholesterol concentration in yolk. The experiment lasted 90 d and 400 Hisex-Brown hens, aged 27 weeks at the start of the study, were used. 2. There were no statistically significant effects of supplementary copper on egg production, food intake or food conversion efficiency. 3. There were no statistically significant differences between the groups in terms of damaged eggs, egg weight, specific gravity and live weight. 4. At the end of the experiment, the lowest yolk cholesterol concentrations were obtained in the 150 kg/kg copper group and the greatest concentrations were in the control group. 5. Consequently, the use of supplementary copper to provide 150 kg/kg in poultry diets was concluded to decrease yolk cholesterol concentrations without any effect on production performance.     

鸡蛋中胆固醇含量调控原理与措施

随着人口的老龄化,心血管疾病逐渐成为威胁人类健康的重要杀手。临床和流行病学研究发现,动脉粥样硬化是导致心血管疾病的重要因素。而高脂、高胆固醇膳食与动脉粥样硬化有着密切关系。膳食胆固醇(CH OL)来源于动物性食物,鸡蛋是动物性食品中CH OL含量较高的一种,平均213m g/枚[1]。鸡蛋中的CH OL具有升高血浆总CH OL、LDL-CH OL水平的潜在作用。由于担心其CH OL会引起动脉粥样硬化,人们减少了鸡蛋食用。美国人年均消费鸡蛋从1965年的402枚降至1991年的233枚,全美的鸡蛋消费量下降了16%~25%[1]。因此,从改善人们的饮食和健康、提…     

Astaxanthin Z-isomer-rich diets enhance egg yolk pigmentation in laying hens compared to that in all-E-isomer-rich diets

The effects of feeding diets containing astaxanthin with different Z-isomer ratios to laying hens on egg qualities, such as astaxanthin concentration in egg yolk and yolk color, were investigated. As the astaxanthin source, a natural microorganism Paracoccus carotinifaciens was used. Astaxanthin with different Z-isomer ratios was prepared by thermal treatment with different conditions and then added to the basal diet at a final astaxanthin concentration of 8 mg/kg. We found that, as the Z-isomer ratios of astaxanthin in the diet increased, the astaxanthin concentration in egg yolk and the yolk color fan score also increased significantly. Importantly, feeding a 50.6% Z-isomer ratio diet increased astaxanthin concentration in egg yolk by approximately fivefold and the color fan score by approximately 2 compared to that in hens fed an all-E-isomer-rich diet. Moreover, we showed that feeding Z-isomer-rich astaxanthin to laying hens increased plasma astaxanthin concentration by more than five times in comparison to that in hens fed an all-E-isomer-rich diet. These results indicate that Z-isomers of astaxanthin have higher bioavailability than that of the all-E-isomer and thus they exhibit greater egg yolk-accumulation efficiency.     

"家禽肠道疾病及其预防措施"专栏(五) 产蛋母鸡的慢性肠炎

目前处理慢性肠炎的方法,是在不知病因的情况下通过增强母鸡的抵抗力和提高其康复率来控制疾病.这是荷兰两位家禽疾病研究人员的结论.     

Changes in fitness traits associated with selection for divergence in yolk cholesterol concentration

1. Correlated changes in egg production, hatchability, egg weight, age at sexual maturation and body weight of lines selected for divergence in yolk cholesterol were studied in two different populations.

2. Divergence in yolk cholesterol resulted in a highly significant difference in percentage egg production with a negative correlation between yolk cholesterol and egg numbers. However, the calculated total daily mass of cholesterol excreted into the egg was similar in both lines.

3. These results indicate that the physiological mechanism by which these populations responded to selection pressure on the concentration of cholesterol in the yolk was by changing egg numbers rather than total amount of cholesterol excreted.

4. Body weights of the high and low yolk cholesterol lines of the meat type, but not of the layer‐type populations, were significantly different. After four generations the line selected for low yolk cholesterol from the meat‐type population weighed 80% of the line selected for high yolk cholesterol levels.

5. Sexual maturity and egg weight were also significantly different between the high and low yolk cholesterol lines, but these differences could not be related to selection response. No changes in hatchability between the cholesterol lines were observed.