日粮添加碳酸氢钠对蛋鸡肠道菌群多样性的影响

900羽21周龄海兰褐蛋鸡随机分成5组,每组6个重复,每个重复30羽。分别在基础日粮中添加0、0．1％、0．5％、2．5％、5％NaHCO3,持续10周。结果显示,与对照组相比,0．1％组蛋鸡盲肠乳酸菌数量增加,大肠杆菌数量降低,菌群多样性指数提高（P〉0．05）。0．5％组蛋鸡粪便pH值显著提高（P〈0．05）,乳酸菌数量增加,菌群多样性指数提高（P〉0．05）。2．5％、5％组蛋鸡粪便pH值、水分含量极显著高于其他组（P〈0．01）。同时,2．5％、5％组盲肠乳酸杆菌数量降低（P〉0．05或P〈0.05）,大肠杆菌数量增高（P〉0．05或P〈0．05）,5％组菌群多样性指数亦显著降低前3组（P〈0．05）。结果表明,日粮添加NaHCO3超过2．5％,蛋鸡腹泻严重,肠道菌群平衡严重破坏。而当NaHCO3的添加量低于0．5％时,肠道有益菌数量和菌群多样性指数呈增加趋势,蛋鸡生产性能维持正常。因此,本试验提示蛋鸡生产中饲料添加剂NaHCO3最高耐受量为0．5％。     

日粮添加黄芪多糖对蛋鸡机体抗氧化能力和鸡蛋品质的影响

选用540只27周龄海兰褐蛋鸡,随机分为4个处理,每个处理5个重复,每个重复27只鸡。采用单因素完全随机分组设计,对照组饲喂基础日粮,试验组饲喂在基础日粮中分别添加100、200、300mg／kg黄芪多糖的日粮,试验期为70d,探讨日粮中添加不同水平的黄芪多糖对蛋鸡机体抗氧化能力和鸡蛋品质的影响。结果显示：黄芪多糖能不同程度地提高（P〈0．05）血清和蛋黄SOD、血清GSH—Px和T-AOC活性,显著降低（P〈0．05）血清和蛋黄MDA含量、蛋黄胆固醇质量浓度。随着受试时间的延长,各组内血清sOD活性显著升高（P〈0．05）,血清MDA含量和T-AOC活性显著降低（P〈0．05）;对照组的蛋黄MDA含量显著升高（P〈0．05）,而血清GsH—Px活性显著降低（P〈0．05）。结果表明,黄芪多糖能改善蛋鸡机体及其产品抗氧化能力,对蛋黄胆固醇质量浓度有降低作用。     

复合微生态制剂对蛋鸡产蛋性能、蛋品质、血清生化指标和肠道形态的影响

试验在基础饲粮中添加由丁酸梭菌和屎肠球菌组成的复合微生态制剂,研究其对产蛋高峰期蛋鸡的产蛋性能、蛋品质、血清生化指标、肠道形态的影响.选取产蛋率和体重接近的40周龄健康的海兰褐蛋鸡400只,随机分成4组,每组5个重复,每个重复20只鸡.对照组蛋鸡饲喂基础饲粮,抗生素组在基础饲粮中添加200 g/t金霉素,试验1组、2组...     

日粮中添加大豆黄酮对蛋鸡抗氧化能力的影响

为研究日粮中添加大豆黄酮对老龄蛋鸡的抗氧化能力 ,随机抽取 40羽 42 0日龄伊沙蛋鸡 ,分为 2组 ,对照组饲喂基础日粮 ,试验组饲喂基础日粮 +大豆黄酮 (6mg/kg) ,试验期为 30d。结果显示 :与对照组相比 ,试验组蛋鸡血清超氧化物歧化酶 (SOD)水平提高了 6 2 4 % (P <0 0 5) ;肝脏组织及下丘脑组织中SOD变化不明显。试验组蛋鸡血清中丙二醛 (MDA)水平降低了 1 8 48% (P <0 0 5) ;肝脏和下丘脑组织中MDA水平分别降低了 34 48% (P <0 0 1 )和 2 5 0 7% (P <0 0 5)。同时 ,日粮中添加大豆黄酮后 ,蛋鸡产蛋率提高了 1 4 41 % (P <0 0 5) ,料蛋比降低了 6 2 5 % (P <0 0 5)。表明日粮中添加大豆黄酮可在一定程度上提高老龄蛋鸡机体的抗氧化能力和生产性能     

维生素E对蛋鸡产蛋后期产蛋性能和蛋品质的影响

文章旨在研究日粮中不同梯度维生素E添加水平对蛋鸡产蛋后期产蛋性能和蛋品质的影响.试验选择60周龄罗曼白壳商品蛋鸡300羽,试验随机分为5组,添加水平分别为0(对照组),30、60、120、240 mg/kg,每组6个重复,每个重复10羽鸡,预试期1周,正试期8周.结果表明:与对照组相比,蛋鸡产蛋后期日粮中添加120 m...     

Effects of an 'enrichment feeder' on behavior and feather conditions of caged laying hens

The objective of this study was to compare the behaviors and feather conditions of caged laying hens fed by two different types of feeders. Seven tennis balls were placed on the feed trough to hide the feed for each of 6 experimental cages (treatment B). The same feed troughs without balls were used for 6 control cages (treatment NB). Forty-eight commercial white leghorn type hens were housed as 4 birds per cage (474 cm² per bird). The experimental period was from 22 to 32 weeks of age. At 28 weeks of age, the hens spent more time feeding in treatment NB (35%) than in B (27%). On the other hand, prefeeding behavior (extension of the neck over the trough or pecking at the balls) occupied more time in B (14%) than in NB (6%). The birds in B spent more time thrusting (thrusting other birds aside and trying to eat) than did the birds in NB (2 vs 0%). At 32 weeks of age, the mean proportion of hens feeding and prefeeding behavior in both treatments was similar to those at 28 weeks of age; however, differences of the behavior between the B and NB were relatively small. Feather damage on a scale of 0 (no damage) to 15 (denuded) increased with age, and the scores in B were less than those in NB at 27 weeks (0.75 vs 1.37), although not at 32 weeks. Egg production in the two treatments was the same, and the type of feeder used did not affect body weight. This device might provide hens with a more attractive environment than the conventional feeders; however, the enrichment feeder might need more improvement for the welfare of caged laying hens.     

Montmorillonite improved the intestinal mucosal barrier functions of laying hens in late production

This study was conducted to investigate the effects of dietary supplementation with montmorillonite (MMT) on performance, intestinal endotoxin concentration, gut mucosal oxidation status, intestinal morphology and permeability, and immunological barrier function of laying hens during late production. Four hundred and eighty 75‐week‐old laying hens (Lohmann Brown) were randomly assigned to five treatments with eight replicates per treatment and 12 hens in each replicate. The hens were fed the basal diet supplemented with 0 (control), 0.3, 0.6, 0.9, or 1.2 g MMT/kg for 70 days. Compared with the control, supplemented with 0.9 g MMT/kg increased egg mass significantly (p < 0.05) during weeks 1–5 of the experiment. Supplemented with 0.6 and 0.9 g MMT/kg also increased the endotoxin concentration in the ileal digesta (p < 0.05), but decreased the MDA concentration in the ileum significantly (p < 0.05). The T‐AOC in the jejunum of the group fed 0.3 g MMT/kg was significantly increased (p < 0.05). Compared with the control, the villus height:crypt depth of ileum from the groups fed 0.6, 0.9, and 1.2 g MMT/kg increased significantly (p < 0.05). The sIgA concentration of jejunum in the groups fed 0.6 and 0.9 g MMT/kg was higher (p < 0.05) than the control. The MMT supplementation linearly increased (p < 0.05) the mRNA expression of claudin‐1 and claudin‐5 in the jejunum. Dietary MMT supplementation down‐regulated the mRNA expression of NF‐κB P65 and TNF‐α in the jejunum in a linear and quadratic manner (p < 0.05). The IL‐1β mRNA expression of jejunum in the group fed 0.6 g MMT/kg was lower (p < 0.05) than the control. In conclusion, dietary supplementation with MMT may improve the gut barrier functions and suggests that 0.9 g/kg of MMT in diets may be the optimal supplemental level for laying hens in late production.     

Effect of dietary threonine on laying performance and intestinal immunity of laying hens fed low‐crude‐protein diets during the peak production period

Threonine (Thr) may be a limiting amino acid for laying hens fed diets with lowered protein level. An experiment was conducted to examine laying performance, and the intestinal immune function of laying hens provided diets varying in digestible Thr levels. Lohmann Brown laying hens (n = 480), 28 weeks of age, were allocated to six dietary treatments, each of which included five replicates of 16 hens. Dietary crude protein (CP) 16.18% diet was offered as the positive control diet. L‐Thr was added to the negative diet (14.16% CP) by 0, 1.0, 2.0, 3.0 and 4.0 g/kg, corresponding 0.44%, 0.43%, 0.49%, 0.57%, 0.66% and 0.74% digestible Thr. At 40 weeks, a reduction in CP level decreased laying performance (p < 0.05). In the low CP, increasing dietary Thr increased (p < 0.05) egg production and egg mass and rose to a plateau between 0.57% and 0.66%. The hens fed 0.66% Thr showed the lowest value (p < 0.05) of feed conversion ratio (FCR). Serum level of uric acid showed the lowest values (p < 0.05) at 0.57–0.66%. In addition, serum‐free Thr maximized (p < 0.05) between 0.66% and 0.74%. Digestive trypsin activity decreased (p < 0.05) when hens fed the low‐CP diet compared with hens fed CP (16.18%) and hens fed 0.57–0.66%. Expressions of ileal MUC2 mRNA maximized (p < 0.05) at 0.66% Thr. Occludin mRNA increased with increasing Thr level (p < 0.05). sIgA mRNA reached to the maximum level (p < 0.05) at 0.66% and 0.74% Thr. INF‐γ mRNA reached to the lowest level (p < 0.05) at 0.65%. Expressions of ileal IL‐2, IL‐6, IL‐1β mRNA decreased with increasing Thr level (p < 0.05). In conclusion, Thr supplementation resulting in optimal laying performance and stimulated the mucosal immune system, suggesting that it is a limiting amino acid in the low‐crude‐protein diet of laying hens during the peak production period.     

Effects of dietary red pepper on egg yolk colour and histological intestinal morphology in laying hens

To evaluate the effect of three kinds of red pepper supplementation ‘Kagawa Hontaka’ produced at Shiwaku Islands (KHS), Miki (KHM) and Takanotsume (TKT) on production performance, egg quality and intestinal histology in laying hens. A total of 32 laying hens (39 weeks of age) were randomly allotted to four groups, each comprising eight hens. Birds were fed a basal diet supplemented with red pepper at 0% (control), 0.5% KHS, 0.5% KHM and 0.5% TKT, respectively. Compared with the control group, no significant difference (p > 0.05) in feed consumption, final body weight, hen‐day production, egg mass, feed efficiency, shell‐breaking strength, shell thickness, shell ratio, albumen ratio, yolk ratio and Haugh units was observed among the experimental groups. Roche yolk colour fan (RYCF) value increased significantly in all experimental groups (p < 0.05). Furthermore, the KHS and KHM groups showed higher RYCF values than the TKT group (p < 0.05). Spectrophotometric measurements of yolk colour, redness (a*) and yellow index (YI) values were higher in the KHS and KHM groups (p < 0.0001). The yellowness (b*) value was lower in the TKT group (p < 0.05). The lightness (L*) value was lower in the KHS and KHM groups (p < 0.05). Villus height, villus area, cell area and cell mitosis in all intestinal segments tended to be higher in all experimental groups. Jejunal cell area and cell mitosis were higher in experimental groups than in the control group (p < 0.05). The cells on the villus tip surface were protuberated in all experimental groups. In conclusion, the KHS, KHM and TKT groups showed hypertrophied intestinal villi and epithelial cell functions. These results indicate that dietary red pepper has stimulating effect on intestinal villi and the structure of epithelial cells, and the 0.5% KHS and KHM groups improved in egg yolk colour.     

脂肪粉对蛋鸡生产性能及相关理化指标的影响

为探讨饲料中添加脂肪对蛋鸡生产性能的影响,选择300日龄褐壳蛋鸡720只,随机分为3个处理,每个处理分为6个重复;试验组分别添加1％、2％脂肪粉,观测其对蛋鸡生产性能、生理变化及经济效益的影响。结果表明：添加脂肪,可以明显提高（P〈0．05）蛋鸡产蛋率（3．51～5．23％）和蛋重（6．03～8．69％）,降低采食量（3．63～3．67％）,改善饲料报酬（13．08～16．03％）;生理指标检测结果显示,试验组血清T3、T4含量显著提高（P〈0．05）,并且有提高GH、IGF－1含量趋势（P〉0．05）;综合经济效益分析,添加脂肪可以提高蛋鸡养殖效益（16．67～26．98％）。因此,杂粕型蛋鸡饲料中添加脂肪有实际意义。     

Salmonella in Belgian laying hens: an identification of risk factors

Since the 1980s, the prevalence of Salmonella in Belgian poultry layers and broilers has greatly fluctuated with a rise observed in 2003 and a significant decrease in 2005. In order to alleviate the risk at egg consumer level, it is crucial to understand the factors which influence the contamination and the spread of Salmonella in laying hens. To study such determinants we explored the Belgian data from the 2005 baseline study on the prevalence of Salmonella in laying flocks of Gallus gallus in the European Union. The response variables corresponded to presence or absence of Salmonella from dust and faecal samples taken from the environment of a Belgian layer flock. The explanatory variables included: region of Belgium, sampling time (month the flock was sampled), production type (cage or barn and free range), Salmonella vaccination status, flock age and flock size. Analyses of these data were performed using a bivariate logistic regression model assuming independence between the two responses and bivariate generalized estimating equations model, which incorporates the correlation between the two responses on the same flock. The main risk factor that was identified was rearing flocks in cages compared to barns and free-range systems. The results also showed a significant higher risk for Salmonella for a 1 week increase in flocks’ age as well as with a unit increase in the size of the flock.     

寡木糖对蛋鸡生产性能与蛋品质的影响

本试验研究寡木糖对海兰蛋鸡生产性能与蛋品质的影响。将2376羽海兰褐壳蛋鸡(297日龄)随机分为试验组和对照组,每组设6个重复,每个重复198羽。对照组饲喂基础日粮;试验组饲喂添加寡木糖的日粮,每吨基础日粮中添加寡木糖150g。结果表明:试验组蛋重(61.90g)比对照组蛋重(59.25g)提高4.47%,差异显著(P<0.05);试验组产蛋率(81.02%)比对照组产蛋率(77.09%)提高5.1%,差异极显著(P<0.01);试验组成活率(97.87%)比对照组(91.99%)提高6.39%,差异显著(P<0.05);试验组和对照组平均每只蛋鸡日耗料量分别为102.72g和101.79g,差异不显著(P>0.05);试验组和对照组蛋壳厚度、哈夫单位、蛋黄色泽分别为0.37mm和0.36mm、75.01和73.83、6.1和5.97,差异均不显著(P>0.05)。结果表明在蛋鸡基础日粮中添加寡木糖能显著提高蛋鸡生产性能,但对蛋品质没有明显影响。     

几种中药方剂对蛋鸡产蛋中后期生产性能的影响

105羽390日龄罗曼蛋鸡,随机均分5组。以4种中药方剂分别添加饲喂组1-组4鸡群,组5为对照。分别观察用药前(第0周)、用药后各组每周平均产蛋率、羽日蛋重、每周平均枚蛋重以及用药期平均料蛋比、破蛋率等生产性能指标。结果:至第11周时,对照组鸡群每周平均产蛋率仅77.55％,每周平均日蛋重仅52.72g/羽,分别比试验前下降13.72％和4.82 g;而组1和组2鸡群产蛋率仅分别下降4.76％和0.21％,日蛋重反而分别增加0.28g/羽和3.41g/羽。其余2组结果与对照组相近。组1和组2平均料蛋比分别为2.25和2.2,显著小于对照组5。组1和组2破蛋率比组5低4—5倍。结论:方1和方2可以明显提高产蛋中后期蛋鸡生产性能。     

不同硒源对蛋鸡生产性能和硒沉积的影响

文章旨在研究日粮添加不同硒源及不同水平对蛋鸡生产性能和鸡蛋中硒沉积量的影响。试验选择产蛋率一致的海兰褐壳蛋鸡720只,随机分为5组,每组6个重复,每个重复24只鸡。试验共设计5种日粮,对照组饲喂基础日粮(不添加硒),处理组分别在基础日粮中添加2个水平的无机硒(0.4和0.8mg/kg硒,亚硒酸钠)以及2个水平的酵母硒(0.4和0.8mg/kg硒),试验共进行16周。结果发现,无论日粮添加酵母硒还是无机硒,随着硒添加水平的升高,蛋鸡生产性能均无显著影响(P>0.05)。从第9周到试验结束,0.4mg/kg无机硒和0.8mg/kg酵母硒组较对照组和0.8mg/kg无机硒组显著提高了蛋鸡的产蛋率(P<0.05)。试验第9周开始,对照组、0.8mg/kg无机硒组和0.4mg/kg酵母硒组产蛋率显著降低(P<0.05)。随着日粮无机硒或酵母硒添加水平的升高,鸡蛋中硒的沉积量显著线性增加(P<0.05)。从第4周开始到试验结束,无机硒或酵母硒组较对照组均显著提高了鸡蛋中硒含量(P<0.05)。在同一硒添加水平及同一时间下,酵母硒较无机硒显著提高了鸡蛋硒含量(P<0.05),随着试验时间的增加,对照组鸡蛋硒含量显著降低(P<0.05)。因此,在本试验条件下,日粮硒的来源和添加水平直接影响鸡蛋硒沉积量,酵母硒较无机硒显著提高了鸡蛋硒沉积量。日粮中酵母硒的添加量可以达到0.8mg/kg,对蛋鸡生产性能无负面影响。     

芽孢杆菌制剂对蛋鸡产蛋性能、血清相关指标及肠道菌群的影响

将480只30周龄海赛克斯褐壳蛋鸡随机分成4组,每组4个重复,每个重复30只鸡。对照组（Ⅰ组）饲喂基础日粮,试验组（Ⅱ～Ⅳ）分别在基础日粮中添加100、200、300mg／kg水平的芽孢杆菌制剂。结果显示,Ⅱ组产蛋率显著高于Ⅰ组和Ⅳ组（P〈O．05）,料蛋比有所降低但不显著（P〉0．05）。Ⅱ组白蛋白和血糖含量显著高于Ⅰ组和Ⅳ组（P〈0．05）,芽孢杆菌对总蛋白、尿酸、总胆固醇和甘油三酯无显著性影响（P〉0．05）。各试验组ⅠgA和IgG含量均比对照组有所提高,但差异不显著（P〉0．05）。Ⅱ组和Ⅲ组C3浓度显著高于Ⅰ组（P〈0．05）,Ⅱ组C4浓度显著高于Ⅰ组和Ⅳ组（P〈0．05）。Ⅱ组和Ⅲ组回肠大肠杆菌的数量较Ⅰ组显著降低（P〈0．05）,乳酸杆菌显著提高（P〈O．05）。结果表明,芽孢杆菌制剂能够改善蛋鸡的生产性能,提高机体免疫力,促进肠道健康;蛋鸡日粮中添加100mg／kg芽孢杆菌制剂效果最佳。     

有机源锌和锰对蛋鸡生产性能、蛋壳和骨质量的影响

文章旨在研究日粮添加有机源锌和锰替代无机锌和无机锰对蛋鸡生产性能、蛋壳和骨骼质量的影响。试验选择31周龄产蛋性能接近的罗曼粉壳蛋鸡616只,随机分为7组,每组4个重复,每个重复22只。基础日粮锌和锰含量分别为50和30 mg/kg,对照组饲喂基础日粮,分别添加氧化锌和硫酸锰(锌40 mg/kg,锰60 mg/kg)。处理组分别在基础日粮中添加20 mg/kg有机锌,30 mg/kg有机锰、20 mg/kg有机锌+30 mg/kg有机锰、40 mg/kg有机锌、60 mg/kg有机锰、40 mg/kg有机锌+60 mg/kg有机锰,上述含量均以相应元素计。试验共进行7周。结果显示:日粮用有机锌或锰替代50%或100%无机锌、锰对蛋鸡生产性能相关参数均无显著影响(P> 0.05)。对照组相比,有机锌或锰替代无机锌或锰的比例对32、46、60和74周龄蛋鸡蛋壳相对重量、蛋壳密度和蛋壳厚度均无显著影响(P> 0.05)。与对照组相比,30 mg/kg有机锰、20 mg/kg有机锌+30 mg/kg有机锰组的蛋壳强度显著提高(P <0.05)。40 mg/kg有机锌+60 mg/kg有机锰组较无机锌、锰组显著提高了60、74周龄及全期蛋壳强度(P <0.05)。日粮添加有机锌或锰对胫骨物理参数及胫骨和趾骨灰分含量均无显著影响。结论 :日粮添加有机锌、锰替代无机锌锰对蛋鸡产蛋性能和骨质量无影响,但可以降低蛋鸡由于年龄升高对蛋壳强度的负面影响。     

A pecking device as an environmental enrichment for caged laying hens

To improve the welfare of caged laying hens, a pecking device made of stones was introduced on the cage floor. Twenty‐four White Leghorn hens aged 15 months were divided into four groups: single‐housed hens with device, single‐housed control hens, pair‐housed hens with device and pair‐housed control hens. Hens housed with the device pecked at various pecking objects less often than control hens. Agonistic behavior was also lower in hens with the device than in hens without the device, implied a possibility of improvement in quality of pecking stimuli with the device. Not only time spent pecking, but also quality of pecking might be important to fill their need for stimulation. Both single‐ and pair‐housed hens more often pecked at the device in the evening. Response to various pecking objects also showed that pecking behaviors were most frequently expressed in the evening. Increased foraging at dusk is a well‐known habit; therefore, the increase in pecking behavior in the evening might reflect the hens' general circadian rhythm. These results indicate that the device made of stones could promote some instinctive behavior. Enhancement of behavioral repertories and reduced agonistic behavior with the pecking device might improve the welfare of caged laying hens.     

The effects of formic acid-treated shrimp meal on laying performance and egg quality in aged laying hens

An experiment was carried out to measure the suitability of using formic acid-treated shrimp meal (TSM) as a protein source for aged laying hens. Shrimp meal (SM), air-dried shrimp waste was treated with 3% formic acid (w/v) at room temperature for 20 min, sun-dried, ground to pass through 1.0 mm mesh screen and then ready to use as the TSM. A total of 56 Single Comb White Leghorn hens, 85 wk of age, were placed in individual cages and assigned randomly into 7 dietary groups of 8 birds each. A control diet, diets containing 5, 10, and 15% SM and diets containing 5, 10, and 15% TSM were prepared. Diets and water were given ad libitum during the 30-d experimental period. Hen-day egg production, egg mass, feed intake, and feed conversion ratio (FCR) were deteriorated with increasing levels of the SM in the diets (P < 0.05). In contrast, these parameters were unchanged with increasing levels of the TSM in diets and compatible with the control group. No significant improvements were observed in exterior or interior egg quality among the dietary groups, except for eggshell weight, strength and yolk color, which were significantly increased in SM and TSM groups when compared to the values in control group (P < 0.05). It is concluded that inclusion of TSM up to 15% in laying hen diets may have beneficial effects on laying performance along with improved eggshell quality and yolk color, and suggested that TSM is a promising combined source of protein and calcium in aged laying hens.     

Effects of Antimicrobial peptides on egg production,egg quality and caecal microbiota of hens during the late laying period

This study was conducted to determine the effects of diet supplementation of laying hens with antimicrobial peptides (AMP) on egg production, egg quality and caecal microbiota. A total of 360 Hy‐Line Brown laying hens (72 weeks old) were divided into three groups with four replicates of 30 birds each. The laying hens were fed with the basal diet (Control), the basal diet + 50 mg/kg AMP (group 1) and the basal diet + 100 mg/kg AMP (group 2). The experiment lasted for 45 d. Eggs were collected daily and caecal samples were collected at the end of the experiment. The results showed that AMP supplementation caused a significantly increased laying rate and decreased feed/egg ratio (p ＜ .05). Meanwhile, a distinctive difference in cecal microbiota was observed between AMP and control groups and the average values of microbial diversity and richness were lower in the AMP group than in the control group. At the phylum level, the relative abundance of Verrucomicrobia and Cyanobacteria were lower in the AMP group than in the control group. In conclusion, the results indicated that dietary supplementation with AMP can improve egg production and affect the cecal microbial community membership and structure of hens during late laying period.