饲粮添加不同水平果胶寡糖螯合锌对肉仔鸡生长性能、免疫功能和血清抗氧化功能的影响

本试验旨在研究饲粮添加不同水平果胶寡糖螯合锌(zinc-pectic oligosaccharide chelate,Zn-POS)对爱拔益加(AA)肉仔鸡生长性能、免疫功能和血清抗氧化能力的影响。选用1日龄健康、体况较一致的AA肉仔鸡480只(公母各占1/2),根据体重一致原则随机分为5组,每组6个重复,每个重复16只鸡。其中Ⅰ组为基础饲粮组;Ⅱ组为抗生素组,在基础饲粮中添加62.5 mg/kg黄霉素;Ⅲ、Ⅳ和Ⅴ组为Zn-POS组,在基础饲粮中分别添加300、600和900 mg/kg Zn-POS。试验期42 d。结果表明:1)1~21日龄,与Ⅰ组相比,Ⅲ、Ⅳ组平均日增重显著提高(P0.05);与Ⅱ组相比,Ⅲ、Ⅳ组体重显著提高(P0.05)。22~42日龄,与Ⅰ组相比,Ⅲ、Ⅳ组平均日增重显著提高(P0.05),Ⅳ组平均日采食量显著提高(P0.05)。1~42日龄,与Ⅰ组相比,Ⅳ组平均日增重极显著提高(P0.01),Ⅲ、Ⅴ组平均日增重显著提高(P0.05),Ⅳ组平均日采食量显著提高(P0.05);Ⅱ组平均日增重极显著高于Ⅰ组(P0.01)。2)Ⅱ组法氏囊指数显著高于Ⅰ组(P0.05),但Ⅱ组血清中免疫球蛋白G水平显著低于Ⅰ组(P0.05)。3)Ⅲ组血清总超氧化物歧化酶活性极显著高于Ⅰ组(P0.01),Ⅲ、Ⅴ组血清过氧化氢酶活性显著高于Ⅰ组(P0.05);Ⅳ、Ⅴ组血清丙二醛含量显著低于Ⅲ组(P0.05)。由此可见,饲粮中添加Zn-POS能改善1~42日龄AA肉仔鸡生长性能、免疫功能和血清抗氧化功能,以600 mg/kg添加水平较为适宜。     

日粮中不同锌添加水平对蛋鸡生产性能及蛋中锌含量的影响

为探讨不同锌添加水平的日粮对蛋鸡生产性能及蛋锌含量的影响,将氧化锌分别以1200mg/kg、1400mg/kg、1600mg/kg、1800mg/kg、2000mg/kg五种锌含量水平添加到蛋鸡基础日粮中,饲喂166日龄的海兰灰产蛋鸡28d,观察蛋鸡生产性能及第18天和第28天蛋锌含量的变化。结果表明:随日粮中锌添加水平的增加,采食量随着日粮锌添加水平的升高表现越明显;产蛋率随着日粮中锌添加水平的增高显著下降(P0.05);饲喂锌含量水平添加为2000mg/kg的鸡蛋锌含量显著高于其他处理组(P0.05),其余处理组鸡蛋锌含量差异不显著(P0.05)。     

天蚕素抗菌肽对产蛋后期蛋鸡生产性能、蛋品质及肠道黏膜形态的影响

试验旨在研究饲粮中添加不同水平抗菌肽对产蛋后期蛋鸡生产性能、蛋品质和肠道黏膜形态的影响。试验选用70周龄产蛋率相近的海兰褐蛋鸡270只,随机分为3个处理,每处理6个重复,每个重复15只鸡,分别为对照组(基础饲粮)、试验Ⅰ组(基础饲粮+50 mg/kg天蚕素抗菌肽)、试验Ⅱ组(基础饲粮+100 mg/kg天蚕素抗菌肽),预饲期7 d,正试期45 d。结果表明:(1)试验Ⅰ、Ⅱ组料蛋比显著降低(P0.05),试验Ⅱ组产蛋率显著高于试验Ⅰ组与对照组(P0.05),试验Ⅰ组与对照组无显著差异(P0.05)。(2)与对照组相比,试验Ⅰ、Ⅱ组蛋鸡的蛋壳厚度、蛋壳强度、蛋形指数、蛋白高度、哈氏单位、蛋黄相对重、蛋壳相对重、蛋黄胆固醇含量均无显著变化(P0.05)。(3)与对照组相比,试验Ⅰ、Ⅱ组回肠绒毛高度显著提高(P0.05),十二指肠、空肠绒毛高度以及十二指肠、空肠、回肠隐窝深度、VH/CD值、肠壁厚度无显著变化(P0.05),但回肠肠壁厚度试验Ⅰ组显著低于试验Ⅱ组(P0.05)。由此可见,在产蛋后期蛋鸡饲粮中添加适宜剂量抗菌肽(100 mg/kg)可提高蛋鸡生产性能,改善肠道黏膜形态。     

丁酸梭菌对蛋鸡产蛋后期生产性能、蛋品质及肠道组织形态的影响

为了研究饲粮中添加丁酸梭菌对蛋鸡产蛋后期生产性能、蛋品质及肠道组织形态的影响,选取270只70周龄产蛋率接近的海兰褐蛋鸡,随机分为3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Ⅰ、Ⅱ组在基础饲粮中分别添加2.5×10~8 CFU/kg、5×10~8 CFU/kg丁酸梭菌。预试期7 d,正试期45 d。结果表明:(1)饲粮中添加丁酸梭菌能够显著提高蛋鸡产蛋后期的产蛋率(P0.05),但对蛋鸡的平均日产蛋重、平均日采食量、料蛋比及破软蛋率无显著影响(P0.05);(2)饲粮中添加丁酸梭菌对蛋鸡产蛋后期的平均蛋重、蛋白高度、哈氏单位、蛋壳强度、蛋壳厚度、蛋形指数、蛋黄相对重、蛋壳相对重及蛋黄胆固醇含量无显著影响(P0.05);(3)饲粮中添加丁酸梭菌能显著提高蛋鸡空肠、回肠的绒毛高度、回肠的绒隐比及十二指肠、回肠的肠壁厚度(P0.05),且饲粮中添加2.5×10~8 CFU/kg丁酸梭菌能够显著提高蛋鸡十二指肠的绒毛高度(P0.05)。由此可见,在该试验条件下,饲粮中添加丁酸梭菌能够改善蛋鸡产蛋后期的生产性能和肠道组织形态。     

虫草多糖对蛋鸡产蛋后期生产性能、蛋品质和肠道形态结构的影响

本试验旨在研究虫草多糖对产蛋后期蛋鸡生产性能、蛋品质和肠道形态结构的影响。试验选取70周龄产蛋率相近的海兰褐蛋鸡270只,随机分为3个组,每组6个重复,每个重复15只鸡。试验设对照组(饲喂基础饲粮)、试验Ⅰ组和试验Ⅱ组(分别饲喂在基础饲粮中添加0.01%和0.02%虫草多糖的饲粮)。预试期7 d,正试期45 d。以重复为单位每天记录蛋鸡产蛋数、破软蛋数和蛋重,每周记录其采食量,计算产蛋率、破软蛋率、平均日产蛋重、平均日采食量和料蛋比;试验结束后,蛋鸡禁食12 h,取其十二指肠、空肠和回肠,测定肠道绒毛高度、隐窝深度、肠壁厚度和绒毛高度/隐窝深度。结果表明:与对照组相比,试验Ⅰ组和试验Ⅱ组的蛋鸡产蛋后期的产蛋率以及其空肠、回肠的绒毛高度和十二指肠肠壁厚度显著提高(P<0.05),料蛋比显著降低(P<0.05);试验Ⅱ组蛋鸡的平均日产蛋重显著提高(P<0.05),但饲粮中添加不同剂量的虫草多糖对蛋鸡产蛋后期的破软蛋率和蛋品质均无显著影响(P>0.05)。综上所述,蛋鸡产蛋后期饲粮中添加0.01%和0.02%的虫草多糖可提高其生产性能,改善肠道形态结构。     

女贞子粉对蛋鸡产蛋后期生产性能、蛋品质及肠道组织形态的影响

试验旨在研究在饲粮中添加不同水平女贞子粉对蛋鸡产蛋后期生产性能、蛋品质和肠道组织形态的影响。试验选用70周龄产蛋率相近的海兰褐蛋鸡270只,随机分为3个组,每组3个重复,每个重复30只鸡,分别为对照组(基础饲粮)、试验Ⅰ组(基础饲粮+1%女贞子粉)、试验Ⅱ组(基础饲粮+2%女贞子粉),预饲期7 d,正试期30 d。结果表明:(1)与对照组相比,试验Ⅰ、Ⅱ组均显著提高了蛋鸡产蛋率(P0.05),但对蛋鸡料蛋比、破蛋率、平均日产蛋重、平均日采食量无显著影响(P0.05)。(2)与对照组相比,试验Ⅰ、Ⅱ组蛋鸡的平均蛋重、蛋壳厚度、蛋壳强度、蛋形指数、蛋白高度、哈氏单位、蛋黄相对重、蛋壳相对重、蛋黄胆固醇含量无显著变化(P0.05)。(3)与对照组相比,试验Ⅰ组显著提高了蛋鸡空肠、回肠绒毛高度(P0.05);试验Ⅱ组显著提高了蛋鸡回肠绒毛高度、绒毛高度/隐窝深度、十二指肠肠壁厚度(P0.05),但也显著降低了蛋鸡十二指肠和空肠绒毛高度(P0.05)。由此可见,在蛋鸡产蛋后期饲粮中添加适宜剂量(1%)的女贞子粉可提高蛋鸡生产性能,改善肠道组织形态。     

饲粮烟酸添加水平对产蛋期种鹅产蛋性能、蛋品质和血清生化指标的影响

本试验旨在研究饲粮烟酸添加水平对产蛋期种鹅产蛋性能、蛋品质和血清生化指标的影响。选择34周龄体况相近的种鹅180只,随机分为6组,每组6个重复,每个重复5只鹅(1公4母)。各组(Ⅰ～Ⅵ组)饲粮烟酸添加水平分别为0、10、20、30、40、50 mg/kg。预试期1周,正试期10周。结果表明:1)饲粮烟酸添加水平对产蛋期种鹅平均日采食量、产蛋率、平均蛋重影响不显著(P0.05);但当饲粮烟酸添加水平为40 mg/kg时平均日采食量、产蛋率、平均蛋重均达到最大值。Ⅴ组的料蛋比显著高于Ⅰ和Ⅱ组(P0.05)。2)饲粮烟酸添加水平对产蛋期种鹅蛋形指数、蛋白高度、蛋黄颜色、蛋黄比率和哈氏单位影响不显著(P0.05)。Ⅴ组蛋壳强度显著高于Ⅰ、Ⅱ、Ⅲ组(P0.05),Ⅴ组蛋壳厚度显著高于Ⅰ、Ⅱ组(P0.05)。3)饲粮烟酸添加水平对产蛋期种鹅血清总蛋白、白蛋白、葡萄糖、尿酸含量及谷草转氨酶活性影响不显著(P0.05)。Ⅳ、Ⅴ、Ⅵ组血清甘油三酯含量显著低于Ⅰ、Ⅱ组(P0.05),Ⅲ、Ⅳ、Ⅴ、Ⅵ组血清总胆固醇含量显著低于Ⅰ组(P0.05),Ⅰ组血清低密度脂蛋白胆固醇含量显著或极显著高于其他各组(P0.05或P0.01),Ⅴ、Ⅵ组血清高密度脂蛋白胆固醇含量显著或极显著高于Ⅰ组(P0.05或P0.01)。由此可见,饲粮添加烟酸可以降低产蛋期种鹅料蛋比,提高蛋壳厚度和蛋壳强度,降低血清中甘油三酯、总胆固醇、低密度脂蛋白胆固醇含量,提高血清高密度脂蛋白胆固醇含量。建议产蛋期种鹅饲粮烟酸添加水平为40 mg/kg,此时饲粮中烟酸总含量为69.16 mg/kg。     

维生素E对免疫抑制产蛋鸡生产性能和蛋品质的调控效应

试验探讨维生素E对免疫抑制蛋鸡生产性能和蛋品质的调控效应,选取健康的尼克褐产蛋鸡270只,随机等分为5组,每组3个重复,每重复18只。第Ⅰ组为对照组,第Ⅱ~Ⅴ组为免疫抑制组,对第Ⅱ~Ⅴ组鸡在试验第5、6、7 d进行腿部肌肉注射80 mg/kgBW环磷酰胺(CTX),第Ⅰ组注射等量生理盐水。Ⅰ、Ⅱ组饲喂基础日粮(维生素E含量44.59 mg/kg),Ⅲ、Ⅳ、Ⅴ组在基础日粮中分别添加50、100、200 mg/kg维生素E。结果显示:①免疫抑制产蛋鸡的产蛋率、平均蛋重和平均日采食量显著降低(P<0.05),破蛋率显著升高(P<0.05)。基础日粮中添加50 mg/kg维生素E显著提高免疫抑制产蛋鸡的产蛋率、平均蛋重和平均日采食量(P<0.05),但仍低于对照组Ⅰ(P<0.05);显著降低料蛋比和破蛋率(P<0.05)。②免疫抑制产蛋鸡的蛋壳厚度、蛋壳强度和哈氏单位显著降低(P<0.05),蛋形指数和蛋黄颜色无显著改变(P>0.05);50 mg/kg维生素E添加量显著提高免疫抑制产蛋鸡的蛋壳厚度、蛋壳强度和哈氏单位(P<0.05),与对照组Ⅰ无显著差异(P>0.05)。因此,免疫抑制显著降低产蛋鸡的生产性能和蛋品质;基础日粮中添加维生素E对免疫抑制蛋鸡的生产性能和蛋品质具有明显的调控效应,且以50 mg/kg添加量效果较好。     

壳寡糖复合物对蛋鸡生产性能和蛋品质、血清生化指标的影响

本试验旨在研究以壳寡糖、L-抗坏血酸、丁酸钙等为主要成分的壳寡糖复合物对蛋鸡生产性能、蛋品质和血清生化指标的影响。选取体重和产蛋率相近的35周龄海兰褐蛋鸡630只,随机分为3组,每组7个重复,每个重复30只。对照组饲喂基础日粮,试验Ⅰ组在基础饲粮中添加壳寡糖复合物A (含壳寡糖20mg/kg),试验Ⅱ组在基础饲粮中添加壳寡糖复合物B (含壳寡糖40mg/kg),试验期30d。结果表明:1)各组之间的产蛋率、破损蛋率、平均蛋重、蛋料比、平均采食量均无显著性差异,试验组蛋重有提高趋势,料蛋比和破损蛋率有降低趋势;2)试验Ⅰ、Ⅱ组的蛋形指数极显著低于对照组,对照组的蛋黄色度值显著高于试验组,其他指标蛋壳厚度、蛋壳强度、蛋壳比例、哈夫单位、蛋黄比例、蛋黄高度各组之间均无显著性差异;3)各处理组之间的血清中钙、磷、总蛋白、白蛋白、球蛋白、尿酸、葡萄糖、甘油三酯含量及谷丙转氨酶、谷草转氨酶活性均没有显著性差异,钙、磷、甘油三酯、丙转氨酶、谷草转氨酶活性有增加趋势,总蛋白、白蛋白、球蛋白、尿酸有降低趋势。由此可见,添加壳寡糖复合物可以提高蛋鸡的生产性能,改善蛋壳质量,以添加20mg/kg壳寡糖的复合物A的饲用效果较佳。     

羟基蛋氨酸螯合锰/锌对产蛋鸡蛋壳品质及微量元素沉积的影响

本试验旨在研究羟基蛋氨酸螯合锰/锌替代产蛋鸡饲粮中无机锰/锌对产蛋鸡蛋壳品质及微量元素沉积的影响。试验采用单因子设计,共设3个组,羟基蛋氨酸螯合锰/锌分别替代基础饲粮中相应无机锰、锌水平的0、50%和100%。每个组6个重复,每个重复10只60周龄、体重相近的海兰褐蛋鸡,试验期60d,分为2个阶段。结果表明:1)饲粮中不同添加形态的微量元素对产蛋率、平均蛋重、日产蛋量、料蛋比和破蛋率无显著影响(P0.05);2)使用有机微量元素,在减少微量元素的添加量情况下,不影响蛋品质(P0.05);3)饲粮中添加有机微量元素可以显著减少粪便中微量元素铜、锌和锰的排放量(P0.05)。由此可见,在蛋鸡产蛋后期使用有机微量元素有提高产蛋率、日产蛋量和降低料蛋比的趋势;使用有机微量元素在减少微量元素使用量的情况下,降低了粪中微量元素的排放量。     

鸡蛋、乌鸡蛋、鹌鹑蛋营养成分的测定比较

禽蛋是人们生活中的重要营养源,是天然食物中最理想的蛋白质。本试验测定了鸡蛋、乌鸡蛋和鹌鹑蛋中的水分、脂肪、蛋白质、磷脂、胆固醇、维生素B2和氨基酸的含量,通过数据对比分析,得到如下结果:乌鸡蛋具有较高的营养价值,鹌鹑蛋由于含有很高的胆固醇,并不适合老年人的食用。鸡蛋的蛋白质、磷脂和氨基酸含量均低于乌鸡蛋和鹌鹑蛋,其营养价值最低。     

Heritabilities and correlations for egg shell crack frequency,body checking,egg number and egg weight in laying hens

1. Egg shell cracks and body checking were assessed on a total of 25 776 eggs collected from 744 hens of two selected White Leghorn strains between 65 and 72 weeks of age.

2. The sire‐component heritabilities in the two strains, respectively, were 0–59 ± 0.23 and 0.36 ± 0.20 for total cracks and 0.41 ± 0.20 and 0.49 ± 0.22 for body checking. The heritabilities for hole, star and hair cracks ranged from ‐0.03 ± 0.13 to 0.66 ± 0.24.

3. The frequency of total cracks did not bear any significant antagonistic relationship with body checking, egg number and egg weight. Body checking had variable relationship with egg number and egg weight. The correlations of shell cracks and body checking with each other and with egg number and egg weight appeared to vary between the strains.     

Studies on egg shell strength,shell stiffness,shell quantity,egg size and shape

Physical properties which included shell stiffness, egg weight, width and length, shell weight and thickness, percentage shell, shell weight per unit area, shape index and roundness were studied in relation to maximum force and energy absorbed at failure in 2733 eggs produced by sixty SCWL pullets. Pooled‐egg, bird‐average and individual‐bird bases were used for correlation and regression analyses.

All physical properties in combination accounted for 61.9 and 88.2 per cent of the variation in force and 19.6 and 59.5 per cent of energy absorbed at failure in pooled‐egg and bird‐average analyses respectively. The non‐destructive measurements of shell stiffness, egg size and shape gave R ² values of 60.5 and 86.9 per cent with force and 16.2 and 55.0 per cent with energy in corresponding analyses.

Shell stiffness proved to be the most important predictor of force at failure. Analyses in which variation of shell stiffness was explained by other physical properties supported the conclusion based on theories of elasticity applied to shell structures that shell stiffness was largely an indirect measurement of egg shell quantity together with lesser effects of egg size and shape.

Bird‐to‐bird variation in relations between physical properties and shell strength was evident from individual bird analyses. Coefficients of determination from force at failure regressed on shell stiffness had a mean value of 0.455 with a standard deviation of 0.178 (n = 60).     

Effect of 1 alpha,25-dihydroxycholecalciferol on egg shell quality and egg production

1. The effect of replacing dietary cholecalciferol (D3) by 1 alpha,25-dihydroxycholecalciferol (1,25-(OH)2D3) on egg shell quality and egg production was tested on 32-week-old White Leghorn laying hens over 9 weeks. 2. Hens fed on a diet supplemented with 5 micrograms 1,25-(OH)2D3/kg diet, tended to lay more eggs, and the eggs had significantly higher specific gravity and percentage shell than eggs from control hens fed on a diet supplemented with 27.5 micrograms D3/kg diet. 3. The effect became apparent after about 4 weeks of treatment and persisted until the end of the test. 4. Hens fed on a diet without D3 supplement started to lay very thin or soft shelled eggs within 4 weeks, suggesting that the birds' reserves of D3 or its metabolites were depleted within this period. 5. The results suggest that 1,25-(OH)2D3 can be substituted for D3 in layer diets to improve egg shell quality.     

The hen's egg: Density of egg shell and egg contents

One hundred eggs were used, from hens of seven widely differing strains: two commercial brown‐egg hybrids (one British, one American), two commercial white‐egg hybrids (one British, one Canadian), one broiler strain, one highly inbred strain of laboratory White Leghorns and one laboratory strain of Brown Leghorns. The volume occupied by the shell of each egg was estimated from its surface area—itself estimated by means of a three‐parameter model (Carter, 1968)— and its mean thickness, measured with an anvil micrometer. The volume occupied by the egg contents was estimated by subtracting the shell volume from the egg volume, which was also estimated by means of the three‐parameter model. Mean overall shell density (counting as “shell” all mineral matter and spaces between the outer surface of the mineral shell and a surface through the tips of the mammillae) was estimated, by regressing shell weight on shell volume, to be 2.241 ±0.004 g./cm.³; covariance analysis showed that the strains were homogeneous in this respect. Mean incremental shell density (i.e. the density of shell distal to the mammillary region) was estimated, by regressing shell weight per unit surface area on shell thickness, to be 2.386±0.004 g./cm.³; the strains were homogeneous in this respect too. The mean depth of the intermammillary spaces was estimated to be 19.9 μ. All the residual deviation from the common regression line can be attributed to measurement error. The estimated density of incremental shell is lower than that of calcite; the packing fraction of the crystals in the shell aggregate and/or the atoms in the crystals was estimated to be 92.8 per cent. The density of the egg contents (at the temperature of the bird) was estimated by regressing weight of contents on volume of contents; covariance analysis revealed significant differences between strains, one of the brown‐egg hybrids having the highest density of egg contents, 1.045 g/cm.³, and the laboratory Brown Leghorns the lowest, 1.033; both commercial white‐egg hybrid strains gave a value of 1.040 g./cm.³.     

Effect of dietary energy,protein, and a versatile enzyme on hen performance,egg solids,egg composition,and egg quality of Hy-Line W-36 hens during second cycle,phase two

This study was conducted to evaluate the effect of Rovabio, dietary energy, and protein on performance, egg composition, egg solids, and egg quality of commercial Leghorns in phase 2, second cycle. A 4 × 2 × 2 factorial arrangement of treatments comprising 4 dietary energy levels (2,791, 2,857, 2,923, and 2,989 kcal of ME/kg) and 2 protein levels (15.5 and 16.1%) with and without Rovabio was used. Hy-Line W-36 hens (n = 1,920, 87 wk old) were randomly divided into 16 dietary treatments (8 replicates of 15 hens per treatment). The trial lasted 12 wk. Dietary protein significantly increased feed consumption but decreased yolk color. As dietary energy increased from 2,791 to 2,989 kcal of ME/kg, feed consumption decreased from 98.0 to 94.9 g per hen daily, and yolk color increased from 5.27 to 5.56. There was a significant interaction among dietary protein, energy, and Rovabio on egg production, BW, egg mass, feed conversion, and yolk solids. Egg weight of hens fed the diets supplemented with Rovabio was significantly greater than that of hens fed the diets without Rovabio during wk 3 and 4. However, Rovabio did not significantly influence average egg weight (87 to 98 wk of age). Rovabio supplementation significantly increased BW of hens. These results suggest Rovabio had a small but significant influence on nutrient utilization of commercial Leghorns during phase 2 of the second cycle.     

Vitamin E supplementation can alleviate negative effects of heat stress on egg production,egg quality,digestibility of nutrients and egg yolk mineral concentrations of Japanese quails

The aim of this study was to determine if the negative effects of high ambient temperature (34 degrees C) on egg production, egg quality, digestibility of nutrients, and mineral content of egg yolk could be alleviated by dietary vitamin E (dl-alpha-tocopheryl acetate) supplementation in laying Japanese quails (Coturnix coturnix japanica). Japanese quails (n=240; 7-week-old) were divided into eight groups, 30 birds per group. The quails were fed either a basal diet or the basal diet supplemented with either 125, 250 or 500 mg of dl-alpha-tocopheryl acetate/kg of diet. Birds were kept at 22 degrees C and 55% relative humidity (RH). At 14 weeks of age, the thermo-neutral (TN) group remained in the same temperature as at the beginning of the experiment, whereas the heat stress (HS) group was kept at an environment-controlled room at 34 degrees C and 44% RH for 3 weeks. Heat exposure decreased performance when basal diet was fed (P=0.001). With 250 and 500 mg/kg of diet, an increase in body weight (P=0.01), feed intake (P=0.01), egg production (P=0.001), and improvement in feed efficiency (P=0.01) was found with vitamin E supplementation in quails reared under heat stress conditions (HS). Similarly, egg weight (P=0.01), egg specific gravity (P=0.01), egg shell thickness (P=0.05) and Haugh unit (P=0.01) were positively influenced by vitamin E supplementation. Heat exposure decreased digestibility of dry matter (DM) (P=0.03), organic matter (OM) (P=0.05), crude protein (CP) (P=0.02), ether extract (EE) (P=0.05) and were elevated by supplemental vitamin E (P相似文献   

The influence of handling on egg production,egg shell quality and avoidance behaviour of hens

1. Egg production was similar in non‐handled and in regularly handled hens, but was reduced by handling hens unaccustomed to the procedure.

2. Handling reduced avoidance behaviour (”flightiness“) in growers and pullets but its effect declined with age and it had no influence in these hens when mature.

3. Handling affected egg shell quality; it resulted in an increased incidence of cracks and of equatorial bulges. Previous work has suggested that this defect is an indication of stressors applied at a critical period during egg formation. Therefore, handling may be a stressor.     

Comparison of single- and multi-strain probiotics effects on broiler breeder performance,egg production,egg quality and hatchability

ABSTRACT

1. This study was conducted to investigate the effect of multi-strain probiotic (containing Lactobacillus acidophilus 2.5 × 10⁷ cfu/g, Lactobacillus casei 2.5 × 10⁷ cfu/g, Bifidobacterium thermophilum 2.5 × 10⁷ cfu/g and Enterococcus faecium 2.5 × 10⁷ cfu/g) and single-strain probiotic (Pediococcus acidilactici 1 × 10¹⁰ cfu/g) on broiler breeder performance and gastrointestinal health.

2. A completely randomised trial was conducted using 300 broiler breeder hens (Ross 308) aged 51 weeks old which were randomly allocated to 1 of 5 dietary treatments with 6 replicates per treatment in a 10 week trial. Treatments included (1) the basal diet a negative control, (2) basal diet supplemented with 0.1 g/kg multi-strain probiotic (MS), (3) basal diet supplemented with 0.1 g/kg single-strain probiotic (SS), (4) basal diet supplemented with 0.1 g/kg of both of probiotics (MS+ SS) and (5) positive control basal diet supplemented with 0.5 g/kg oxytetracycline antibiotic (OX).

3. Body weight, egg production, yolk weight, eggshell thickness and weight, Haugh unit, fertility and hatchability were determined. Results showed that dietary treatments had no significant effect on total hen house or total hatching egg production, egg weight, yolk colour index, shell weight, mortality, body weight, fertility, hatchability, oviduct and stroma weight or number of large and small yellow follicles (P > 0.05). None of the jejunum morphological parameters, apparent ileal digestibility of protein and ileal Lactobacillus population were influenced by supplemental probiotics (P > 0.05), although ileum Escherichia coli count was reduced by inclusion of dietary probiotics (P < 0.05).

4. It was concluded that although both probiotic treatments reduced coliforms, they did not improve broiler breeder performance or gastrointestinal tract (GIT) function.