合生素对蛋鸡生产性能及蛋品质的影响

在我国传统养殖生产中,抗生素一直被用作饲料添加剂来控制畜禽疾病和提高生产性能。但随着抗生素的大量使用,其带来的负面影响日趋严重。药物残留和耐药菌株的产生及畜禽产品质量的下降,已对畜牧业可持续发展和人类健康带来严重的影响。研制开发无公害和无残留的饲料添加剂替代     

酶解羽毛粉对蛋鸡生产性能的影响

选用192只23周龄产蛋良好的海兰褐商品蛋鸡,探讨日粮中添加不同比例的酶解羽毛粉对蛋鸡生产性能的影响,设3个处理,每个处理4个重复,每个重复16只鸡,三层阶梯式笼养,自由采食和饮水,进行饲养试验。试验期为30d。对各处理组的蛋鸡日只耗料量、产蛋率、日只产蛋量、平均蛋重、料蛋比的记录数据进行统计分析,研究用羽毛粉代替部分植物蛋白饲料（豆粕）的可行性。结果表明,日粮中添加2．5％和5％酶解羽毛粉对蛋鸡日只耗料量、产蛋率、日只产蛋量、平均蛋重、料蛋比5项指标均无显著影响（P〉0．05）。因此,在蛋鸡日粮中用羽毛粉代替部分植物蛋白饲料原料是经济可行的。大力开发利用羽毛粉,对解决我国目前蛋白资源紧缺的状况具有重要的理论和现实意义。     

Effect of dietary defatted diatom biomass on egg production and quality of laying hens

Background

This study was to determine if feeding laying hens with defatted diatom microalgal biomass (DFA) from biofuel production affected their egg production and health status.

Methods

Five replicates of 5 individually caged ISA Babcock White leghorn hens were fed 4 diets, including a corn-soybean meal control diet, a diet containing 7.5% DFA substituting for soybean meal, and diets containing 7.5% or 15% DFA substituting for corn and soybean meal. Body weights, feed intake, feed conversion ratio (FCR), rate of egg production, egg size, egg mass, and several characteristics of eggs were determined at 4 and 8 wk. Venous blood was sampled at 4 and 8 wk for measurement of 5 biomarkers of health.

Results

The 15% DFA diet decreased (P <?0.05) feed intake, egg production, and plasma uric acid concentrations as compared with the control diet, but increased (P <?0.05) egg albumen weight and height compared with the 7.5% DFA diets. The two levels of DFA produced dose-dependent (P <?0.05) changes in three color measures of egg yolk, without affecting four hen plasma biochemical indicators of health.

Conclusions

Feeding laying hens with 7.5% DFA in the corn-soybean meal diet for 8 wk had no adverse effect on their health, egg production, or egg quality, but 15% inclusion reduced feed intake, egg production, and efficiency of feed utilization.     

Effect of dietary defatted diatom biomass on egg production and quality of laying hens

Background： This study was to determine if feeding laying hens with defatted diatom microalgal biomass （DFA） from biofuel production affected their egg production and health status. Methods： Five replicates of 5 individually caged ISA Babcock White leghorn hens were fed 4 diets, including a corn-soybean meal control diet, a diet containing 7.5% DFA substituting for soybean meal, and diets containing 7.5% or 15% DFA substituting for corn and soybean meal. Body weights, feed intake, feed conversion ratio （FCR）, rate of egg production, egg size, egg mass, and several characteristics of eggs were determined at 4 and 8 wk. Venous blood was sampled at 4 and 8 wk for measurement of 5 biomarkers of health. Results： The15% DFA diet decreased （P 〈 0.05） feed intake, egg production, and plasma uric acid concentrations as compared with the control diet, but increased （P 〈 0.05） egg albumen weight and height compared with the 7.5% DFA diets. The two levels of DFA produced dose-dependent （P 〈 0.05） changes in three color measures of egg yolk, without affecting four hen plasma biochemical indicators of health. Conclusions： Feeding laying hens with 7.5% DFA in the corn-soybean meal diet for 8 wk had no adverse effect on their health, egg production, or egg quality, but 15% inclusion reduced feed intake, egg production, and efficiency of feed utilization.     

甪里艾叶粉对蛋鸡产蛋性能与蛋品质的影响

为了研究甪里艾叶粉对蛋鸡产蛋性能与蛋品质的影响,试验选用50周龄健康状况良好、生产性能相近的海兰褐蛋鸡288只,随机分为四组,一个对照组,三个试验组,各组甪里艾叶粉分别添加0、1%、2%、3%,每组6个重复,每个重复12只鸡,预试期为7 d,试验时间为42 d。结果显示:(1)甪里艾叶粉对产蛋性能的影响:试验各组的平均日产蛋重均高于对照组(P0.05),分别提高了2.62%、3.58%、2.41%;随着艾叶粉添加量的增加,平均日采食量显著减少(P0.05),分别减少了2.76%、3.29%、3.62%;试验各组料重比均显著低于对照组(P0.05),分别降低了5.10%、6.63%、5.61%;随着甪里艾叶粉添加量的增加,产蛋率分别提高了2.85%(P0.05)、3.99%(P0.01)、5.93%(P0.01)。试验各组的蛋重与对照组均无显著差异(P0.05)。(2)甪里艾叶粉对蛋品质的影响:甪里艾叶粉可显著提高蛋的比重(P0.05),其中添加量为2%时差异极显著(P0.01)。各组间的蛋形指数、哈氏单位、蛋黄颜色差异均不显著(P0.05)。但试验各组的蛋白高度分别提高了8.92%(P0.05)、11.29%(P0.05)、10.21%(P0.05),哈氏单位则相应提高了4.51%、5.67%、5.69%。各组间的蛋壳指标差异不显著(P0.05)。试验各组的蛋白比率、蛋黄比率差异不显著(P0.05),随着甪里艾叶粉添加量的增加,蛋壳比率逐渐降低,其中添加2%和3%的甪里艾叶粉可显著降低蛋壳比率(P0.05)。甪里艾叶粉可以改善海兰褐蛋鸡的产蛋性能,蛋的比重和蛋白高度显著提高,蛋壳比率呈降低的趋势。     

牛磺酸对产蛋后期母鸡生产性能的影响

试验采用 14 4只 5 6周龄海兰褐蛋鸡 ,研究添加不同水平的牛磺酸对产蛋后期母鸡生产性能和蛋壳品质的影响。试验结果表明 :添加 0 .0 5 %的牛磺酸能够提高蛋鸡的产蛋率、平均蛋重 ,并且可以降低蛋鸡的日采食量和料蛋比 ,对蛋壳品质也有一定的影响。     

有机稀土和柑桔皮粉对罗曼蛋鸡产蛋量的影响

在基础饲料中分别添加 0 4%的有机稀土 ,2 5 %的柑桔皮粉 ,观察其对罗曼蛋鸡产蛋性能的影响。在 3 8d的试验中 ,蛋鸡采食量、蛋重变异不大 (P >0 0 5 ) ,产蛋量分别提高 2 60 % (P <0 0 5 ) ,5 3 6% (P <0 0 1)。     

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.     

Sand intake by laying hens and its effect on egg production parameters

Soil intake may be the most prominent source of environmental contaminants for free range and organic hens, but there are no quantitative data concerning soil intake by domestic hens. Consumption of soil of 14–32 g a day can be estimated from literature, but such a dilution of nutrient intake seems incompatible with high productivity. In this study laying hens were fed pelleted diets with 0%, 10%, 20%, 25% and 30% of sand addition to determine its effect on productivity. Feed intake, feed and nutrient (feed minus sand) conversion ratio, egg production, egg weight and body weight gain were measured over a 4-week period. Acid insoluble ash concentration in the faeces was measured to determine the accuracy of estimating the soil ingestion by the soil-ingestion equation for wildlife as a way to determine soil ingestion of free range and organic hens under practical circumstances. The hens were able to compensate the dilution of the diet with 20%, 25% and 30% of sand by increasing their feed intake. Feed intake increased significantly and feed to egg conversion ratio decreased significantly with increasing sand levels in the diet. The nutrient to egg conversion ratio of the diet without sand tended to be worse than for the diets with sand, presumably due to the total absence of coarse material in the diet. There were no differences in egg production and egg weight between hens fed the different diets but body weight gain was significantly lower for the hens fed the diets with 20%, 25% and 30% of sand. Estimation of sand ingestion was done by the soil-ingestion equation for wildlife. Provided that the actual dry matter digestibility coefficient of the nutrient part of the diet is taken into account, estimating the soil ingestion according to the soil-ingestion equation for wildlife seems an appropriate way to determine soil ingestion for free range and organic hens under practical circumstances.     

茶皂素对蛋鸡生产性能、蛋品质和养分利用率的影响

试验旨在研究饲粮中添加不同水平茶皂素对蛋鸡生产性能、蛋品质和养分利用率的影响.选取600只40周龄健康的海兰褐商品蛋鸡,随机分为4组,每组6个重复,每个重复25只鸡.对照组饲喂基础饲粮,试验组在基础饲粮中分别添加100、200、300 mg/kg的茶皂素.预试期7d,正式试验期56 d.结果表明:与对照组相比,100、...     

深海鱼肽对鸡蛋品质和蛋鸡消化率的影响研究

以含有深海鱼肽的维他快预混剂、肽多蛋预混料为原料，研究添加0．1％、0．2％的维他快和添加8％的肽多蛋对蛋种鸡、蛋品质的影响，以及维他快对各种营养成分消化吸收的影响。采用试验饲料对蛋鸠进行为期8周的饲养，人工喂料、拣蛋，在试验结束后进行代谢试验及蛋品质的检测。结果表明，添加深海鱼肽有利于改善鸡蛋品质，加强蛋壳质量，提高鸡蛋的营养价值；另外，深海鱼肽能显著提高饲料粗灰分的消化吸收，尤其是磷的吸收，其他各项营养成分差异不显著，但较对照组都有所提高。     

海藻粉对蛋鸡生产性能及蛋品质的影响

在日粮中添加不同比例的海藻粉,研究其对蛋鸡生产性能及蛋品质的影响。选取576只30周龄健康蛋鸡,随机分成4组,每组设3个重复,每个重复48只鸡,第Ⅰ组为对照组,饲喂基础日粮;第Ⅱ、Ⅲ、Ⅳ组在与基础日粮营养水平基本一致的基础上分别添加1%、3%、5%的海藻粉。结果表明,随着添加比例的增加,产蛋率、产蛋量均有不同程度的提高,料蛋比下降;同时能显著改善蛋黄颜色,提高蛋黄中蛋白质、脂肪、磷脂和碘的含量,降低胆固醇在蛋黄中的蓄积。     

日粮中添加女贞子粉对蛋鸡生产性能和蛋品质的影响

选择150只49周龄、平均体重(1.99±0.17)kg的健康海兰褐蛋鸡,采用单因素完全随机分组试验设计,随机分为对照组(基础日粮)、试验组Ⅰ(基础日粮+0.5%女贞子粉)、试验组Ⅱ(基础日粮+1%女贞子粉)。每组设5个重复,每个重复10只蛋鸡,试验期为8周,研究了女贞子粉对蛋鸡生产性能和蛋品质的影响。结果表明:与对照组相比,试验组Ⅰ、Ⅱ产蛋率分别提高了4.86%和11.75%(P0.05)。试验组Ⅰ蛋黄颜色显著高于对照组9.60%(P0.05)。日粮中添加女贞子粉可以提高蛋鸡产蛋率,改善蛋黄颜色,进而提高蛋鸡的生产性能和蛋品质。     

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 the frizzle gene (F) on egg production and egg quality of laying hens kept in tropical villages

1. Two experiments were conducted to determine the influence of the frizzle gene (F) on the production and quality of chicken eggs kept on village farms in Ghana.

2. In the first experiment, 144 pullets, 72 each of Ff and ff pullets from F₁ birds, were compared in a randomised complete block design (RCBD), with three villages and 4 batches of hatch as blocks and the two feather genotypes (Ff and ff) as the treatments.

3. The Ff pullets were superior (P < 0.05) to their ff counterparts in terms of the number of eggs per clutch, egg mass and hen-housed and hen-d rates of lay, whereas age at first egg was lower (P < 0.05) in ff layers compared to Ff ones.

4. The eggs of the F₁ heterozygous frizzle (Ff) layers had higher values for albumen height, Haugh unit and yolk height compared with eggs from their normal feathered counterparts.

5. In the second experiment, 144 pullets, 48 each of FF, Ff and ff pullets, were compared in a RCBD, with three villages and 4 batches of hatch as blocks and the two feather genotypes (Ff and ff) as the treatments.

6. The F₂ birds with genotypes Ff and FF were better than their ff counterparts in terms of the number of eggs per clutch, egg mass, and hen-housed and hen-d rates of lay. Age at first egg was significantly lower in ff layers compared to FF and Ff ones.

7. The Haugh unit value was higher in the homozygous and heterozygous frizzles compared to the normal feathered ones.

8. The presence of the frizzle gene (F) in egg type chickens led to an improvement in egg production and egg quality traits in village chickens, and the cross-breeding scheme evaluated in this project could contribute to improved productivity.     

Effect of production system and flock age on egg quality and total bacterial load in commercial laying hens

The shell of the egg is essential in providing shape to the egg and ensuring safe packaging of the internal contents; however, shell defects have been shown to increase the risk of microbial contamination of eggs. Eggs were collected from commercial cage and free-range flocks at the ages of 25, 35, 45, 55, 65, and 75 wk. From each collection per flock, 30 eggs were processed for the eggshell and egg internal quality determination, 30 eggs for cuticle estimation, 30 eggs for mammillary layer ultrastructural features scoring, and 60 eggs for egg microbial enumeration. Translucency score and shell reflectivity were significantly higher in free-range eggs and increased with flock age in both production systems. Egg weight, shell weight, percentage shell, shell thickness, albumen height, Haugh unit, and yolk color were higher for cage eggs. The amount of cuticle was higher in cage eggs and fluctuated with flock age in both production systems. For the mammillary layer ultrastructural variables, a significant effect of production system and flock age was observed for early fusion, Type A bodies, and Type B bodies, whereas aragonite, depression, erosion, and hole were rarely observed. Variability of mammillary cap size, the incidence of poor mammillary cap quality, incidence of late fusion, alignment, Type A bodies, Type B bodies, and cubic cone formation were greater in the free-range versus cage system and increased with flock age in both production systems. The incidence of confluence and early fusion were greater in cage eggs and decreased with age in both production systems. Significantly lower total microbial load was observed for cage compared with free-range eggs, but the overall bacterial load recorded in this study was low. It can be concluded that cage eggs were better in overall quality when directly compared with free-range eggs.     

鲎素抗菌肽对蛋鸡产蛋后期蛋品质及蛋壳超微结构的影响

旨在探索鲎素抗菌肽对海兰褐蛋鸡产蛋后期蛋品质及子宫CaBP-D28k mRNA表达量的影响及其机理探讨。随机选取600只385日龄海兰褐蛋鸡,分为对照组、试验组,每组各3个重复,每个重复100只鸡。对照组饲喂基础日粮,试验组在基础日粮中添加鲎素抗菌肽,鲎素抗菌肽发酵液最适添加剂量为0.01 L/kg,按饲料所需量配比添加,预饲期7 d,试验期35 d。结果显示,与对照组相比,试验组产蛋率提高8.86%(P0.05),料蛋比、破蛋率分别降低2.68%和12.76%(P0.05);试验组蛋壳强度比对照组提高了18.97%(P0.05),哈氏单位、蛋壳相对质量和蛋壳厚度均有上升的趋势;试验组蛋壳表面皴裂纹数较少,裂隙变小,纵切面结构中垂直晶体层完整,栅栏层结构整齐,上下层面平滑,栅栏层气孔数量少,乳头层乳头数目少且宽;试验组蛋鸡子宫内CaBP-D28k mRNA表达水平显著提升(P0.01)。可见,鲎素抗菌肽可提高CaBP-D28k参与产蛋过程中钙的代谢过程,调控蛋鸡体内钙代谢发挥功能作用。     

复合微生态制剂对蛋鸡生产性能、 蛋品质及抗氧化性能的影响

试验旨在研究饲粮中添加不同比例复合微生态制剂对蛋鸡生产性能、蛋品质及抗氧化性能的影响。选取体重相近的26周龄健康罗曼粉壳蛋鸡240只,随机分为3组,每组设5个重复,每个重复16只鸡。对照组饲喂基础饲粮,试验Ⅰ、Ⅱ组分别在基础饲粮中添加1.5%、3%复合微生态制剂。预试期7 d,正试期42 d,分试验前期(0～21 d)和试验后期(21～42 d)。结果表明:①饲粮添加1.5%、3%复合微生态制剂对全期产蛋率和平均蛋重均无显著影响(P>0.05),但后期产蛋率显著提高(P<0.05),添加3%复合微生态制剂显著降低了全期平均日采食量(P<0.05),极显著降低了后期平均日采食量、料蛋比及全期料蛋比(P<0.01)。②与对照组相比,饲粮添加3%复合微生态制剂有提高试验第21 d蛋黄颜色和蛋壳厚度的趋势(0.050.05)。③饲粮添加1.5%、3%复合微生态制剂均显著提高蛋鸡血清总抗氧化能力(P<0.05),添加3%复合微生态制剂显著降低蛋鸡血清丙二醛含量(P<0.05)。综上所述,蛋鸡饲粮添加复合微生态制剂可提高蛋鸡饲料利用率、抗氧化性能及改善蛋品质,复合微生态制剂的添加水平为3%时效果较佳。     

Segmented polynomial model for estimation of egg production curves in laying hens

1. A model for estimating egg production curves in layers was developed and tested against other existing models. The model uses a three segment polynomial (constant—cubic—linear) and is reparameterised to estimate variables of practical importance.

2. The model predicted future production based on partial data better and estimated egg production curves as well as the currently existing models.