Effects of Different Forced Molting Methods on Postmolt Production,Corticosterone Level,and Immune Response to Sheep Red Blood Cells in Laying Hens

The objective of this study was to evaluate the effects of different molting methods on postmolt production, plasma corticosterone levels, and antibody production to SRBC for the welfare of laying hens. This experiment was conducted with 120 IGH-type Brown laying hens (70 wk of age), randomly divided into 3 experimental groups. The hens in one group were fed a whole-grain barley diet during the first 10 d (WB diet). On d 11, hens consumed 100 g of layer diet/d until d 28. In the second group, hens were fed a Zn diet containing 10,000 mg/kg of Zn as ZnO for 10 d (Zn diet). Hens were then provided 100 g of a layer diet from d 11 to 28. In the third group, feed was withdrawn for 10 d, and on d 11 hens were fed a cracked corn diet ad libitum until d 28 (California method; CAL diet). Hens in all groups were returned to the layer diet ad libitum on d 29. Egg weight was lower in the Zn treatment than in the other treatments. Feed intake and plasma corticosterone levels were higher and antibody production was lower in the CAL treatment than in the WB and Zn groups. The FCR was better in the WB than in the Zn group. Mortality, egg production, and egg quality were not significantly different among the molting methods. As a result, the WB molting program was the best method for postmolt production among the programs examined.     

强制换羽对蛋鸡生产性能和蛋品质的影响

旨在研究强制换羽对蛋鸡生产性能和蛋品质的影响。选取80周龄海兰褐蛋鸡4 500只,分为A、B、C组,每组1 500只,于试验组Ⅰ区饲养;选取60周龄海兰褐蛋鸡3 000只,分为D、E组,每组1 500只,于试验组Ⅱ区饲养;另选取60周龄海兰褐蛋鸡1 500只（F组）,于对照组Ⅲ区饲养。试验组Ⅰ区和试验组Ⅱ区位于同一栋鸡舍,对照组Ⅲ区位于另外一栋鸡舍。采取饲料、饮水、光照控制的方式对A~E组鸡群进行强制换羽处理;F组不进行强制换羽处理。试验包括7 d的预试期和56 d的正试期。在正试期内,测定各组鸡群的产蛋率、蛋品质指标、死亡率。结果表明：与换羽前相比,强制换羽后A、B、C组的平均产蛋率的提高幅度为27.1%,强制换羽后D、E组的平均产蛋率的提高幅度为16.1%,换羽后F组的平均产蛋率的降低幅度为5.5%;5个接受强制换羽处理的试验组（A~E组）与对照组（F组）相比,蛋重增加2.5%,蛋壳强度提高11.8%,蛋白高度提高8.8%,蛋形指数提高3.3%,蛋壳尖端的厚度提高14.8%;5个接受强制换羽处理的试验组（A~E组）的平均死亡率为2.5%,对照组（F组）的死亡率为1.5%。综上所述,强制换羽技术的应用可以明显提高海兰褐蛋鸡的产蛋率,并提升蛋品质。     

不同硒源及硒水平对产蛋鸡生产性能和蛋品质的影响

试验旨在研究添加不同水平的亚硒酸钠和酵母硒对产蛋鸡生产性能和蛋品质的影响。试验选用23周龄北京油鸡和罗曼粉杂交一代产蛋母鸡648只,随机分为12组,每组6个重复,每个重复9只鸡,进行为期8周的饲养试验。试验1~6组在基础日粮中分别添加含硒0.3、1.0、2.0、3.0、4.0、5.0 mg/kg的亚硒酸钠,试验7~12组在基础日粮中分别添加含硒0.3、1.0、2.0、3.0、4.0、5.0 mg/kg的酵母硒。结果表明,在产蛋鸡的饲料中添加5.0 mg/kg以内的亚硒酸钠或酵母硒都有提高产蛋率的趋势(P＞0.05),且对蛋品质无明显不良影响。若以提高产蛋率为目的,亚硒酸钠的添加水平以2.0 mg/kg为宜,酵母硒的添加水平以3.0 mg/kg为宜。酵母硒的使用效果优于亚硒酸钠。酵母硒组采食量和蛋壳强度显著高于亚硒酸钠组(P＜0.05),亚硒酸钠组蛋白高度和哈氏单位显著高于酵母硒组(P＜0.05)。     

高水平硒和碘日粮饲喂产蛋母鸡对蛋营养成分的影响

为评价高硒高碘日粮对蛋鸡生产性能及蛋营养成分的影响,以含Se0.2mg/kg,I0.5mg/kg日粮(对照组),含Se1.2mg/kg,I50mg/kg日粮(试验I组),含Se2.2mg/kg,I100mg/kg日粮(试验Ⅱ组)饲喂产蛋母鸡,观察蛋营养成分的变化。结果表明:与对照组比较,试验组蛋黄硒和碘含量、蛋白硒和碘含量均有大幅度提高;而蛋氨基酸含量、蛋白及蛋黄含水量、蛋白及蛋黄蛋白质含量、蛋黄磷脂含量等营养成分未见明显变化。这些结果提示:产蛋母鸡受高硒高碘日粮作用,在促进日粮硒和碘向蛋中转移的过程中不会对蛋的其它营养成分造成不良影响。     

复合微生态制剂对蛋种鸡生产性能的影响

本试验旨在研究多菌种复合微生态制剂对蛋种鸡生产性能的影响。选用384只15周龄的海兰褐蛋种鸡,随机分成4组,每组4个重复,每个重复24只鸡。对照组饲喂基础日粮,试验1、2、3组在基础日粮中分别添加50、100、200 g/t的复合微生态制剂。结果表明,试验3组的平均蛋重显著高于对照组(P＜0.05),但开产日龄比对照组晚;在27~30周龄时试验2组显著提高了产蛋率并降低了料蛋比(P＜0.05),而试验3组的产蛋率显著降低(P＜0.05),料蛋比升高(P＞0.05);试验组的繁殖性能指标与对照组差异不显著。因此,饲料中添加复合微生态制剂可以提高蛋种鸡产蛋前期的生产性能,本试验中复合微生态制剂的适宜添加量为100 g/t。     

当归补血散对高龄蛋鸡生产性能及蛋品质的影响

120只390日龄海兰褐蛋鸡,随机分为4组。以日粮中分别添加0.5%、1%、1.5%剂量的当归补血散饲喂Ⅰ、Ⅱ、Ⅲ组鸡群,Ⅳ组为对照组。连续给药15 d。分别观察各组每天的产蛋率、日产蛋量等生产性能指标;于第8、15、22、30天各组随机收集10枚蛋测蛋品质指标。结果:试验组Ⅱ、Ⅲ的产蛋率比对照组提高了8.80%(P<0.01)、4.99%(P<0.05);日产蛋量均与对照组差异极显著(P<0.01),分别提高了12.12%、6.82%;料蛋比与对照组相比降低了12.46%(P<0.01)、11.42%(P<0.05)。Ⅱ组的蛋形指数与对照组有显著提高(P<0.05);Ⅰ和Ⅱ组的蛋壳厚度与对照组有显著提高(P<0.05)。其余指标与对照组差异不大(P>0.05)。结论:1%剂量可以明显提高高龄蛋鸡的生产性能和蛋品质。     

饲养方式对蛋鸡产蛋前期生产性能的影响

试验通过对比舍外散放蛋鸡与舍内笼养蛋鸡在体重、胫长和胫围等方面的差异来研究饲养方式对鸡产蛋前期生产性能的影响。结果表明：散放鸡体重在8、10、12周龄显著低于同周龄笼养鸡;散放鸡胫长在10、12周龄显著低于同周龄笼养鸡;散放鸡胫围在10周龄显著低于同周龄笼养鸡。笼养鸡和散放鸡各周龄的胫长和胫围变异系数均小于10%,均匀度均高于或等于80%。两组蛋鸡各周龄体重的变异系数均小于10%,体重均匀度呈逐级递增状态,6周龄蛋鸡体重均匀度较低,到12周龄时均匀度已达到80%。两组蛋鸡的生产性能各指标均达到海兰褐蛋鸡饲养标准。     

副干酪乳杆菌KL1制剂对蛋鸡生产性能、蛋品质及鸡蛋中胆固醇含量的影响研究

旨在利用从藏灵菇中筛选的可显著降低血清胆固醇和耐受胃肠道逆环境的副干酪乳杆菌KL1菌株制备微生态制剂,探讨该制剂在低胆固醇鸡蛋生产中对蛋鸡生产性能、蛋品质及鸡蛋中胆固醇含量的影响.本试验将120只30周龄健康状态良好且产蛋率接近的农大3号矮小蛋鸡随机分为低、中、高剂量试验组和对照组,每组5个重复,每个重复6只蛋鸡,试验...     

Effects of Energy and Protein Levels on Egg Quality and Performance of Laying Hens at Early Second Production Cycle

One hundred sixty-two commercial 70-wk-old ISA Brown laying hens, previously subjected to induced molting by feed restriction, were distributed in a completely randomized design with 3 × 3 factorial arrangement (i.e., 3 metabolizable energy levels: 2,850; 2,950, and 3,050 kcal of ME/kg) and 3 protein levels (16, 18, and 20% CP), which totaled 9 treatments with 3 replicates of 6 birds each. Experimental diets were offered to birds after the feed restriction period. Performance and egg quality parameters were evaluated in 14-d intervals from the 4th to 12th weeks after forced molting for a total of 4 evaluation periods. Increases in dietary energy and protein levels did not improve performance or egg quality. The levels of 2,850 kcal of ME and 16% protein were sufficient for laying hens starting the second production cycle without decreasing their performance or egg quality.     

日粮中添加合生元对蛋鸡生产性能及蛋品质的影响

试验旨在研究日粮中添加合生元对蛋鸡生产性能、蛋品质及经济效益的影响。选用1080只265日龄的正大褐蛋鸡,随机分为6个处理组,每个处理组6个重复,每个重复30只。试验1组为对照组,饲喂玉米—豆粕型基础日粮,试验2~6组在基础日粮中分别添加0.05%、0.1%、0.2%、0.5%和1%合生元,试验期为60 d。结果表明,与对照组相比,试验3、4和5组料蛋比分别降低了6.96(P<0.05)、7.33%(P<0.05)和8.06%(P<0.05),产蛋率分别提高4.05%(P<0.05)、3.54%(P<0.05)和6.17%(P<0.05);试验5组的蛋壳厚度、蛋壳色泽、蛋壳强度和哈氏单位分别提高了5.85%(P<0.05)、6.50%(P<0.05)、15.49%(P<0.05)和2.52%(P<0.05)。因此,0.5%合生元在改善蛋鸡生产性能和蛋品质方面具有显著的效果。     

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。     

冬季有窗封闭式鸡舍内环境参数变化及对蛋鸡生产性能和蛋品质的影响

本试验旨在研究冬季鸡舍内环境参数变化及舍内不同位置对初产蛋鸡生产性能和蛋品质的影响.试验期间每天6:00、12:30、17:00、22:00对舍内9个不同位置(西南角、中南、东南角、中西、中、中东、西北角、中北和东北角)的环境参数(温湿度、光照强度、CO2浓度、NH3浓度、粉尘浓度)测定,并选取243只21周龄的海兰褐蛋鸡,随机分为9组,分别设在测定环境参数的9个点周围,每组27只鸡,即西南组、中南组、东南组、中西组、中组、中东组、西北组、中北组和东北组,各组饲喂相同的日粮,试验期15d.结果表明,舍内环境参数随时间和位置发生变化;中组产蛋率显著高于西南组、中南组、东南组和东北组,中组和中西组采食量显著高于东南组;中组和中西组对蛋品质影响较小.说明舍内主要环境参数在不同时间点及在不同位置处有所变化,中西组和中组所处环境对初产蛋鸡生产性能和蛋品质影响较小.     

脂多糖应激对添加不同锌源蛋鸡免疫反应和组织锌代谢的影响

36只海兰褐壳蛋鸡按2×3因子进行试验,饲喂3种日粮(分别为基础日粮、基础日粮中添加60 mg/kg硫酸盐和氨基酸络合形式的锌),每组随机选取半数腹腔注射脂多糖(LPS),另一半注射同样剂量的生理盐水,研究LPS应激对饲喂不同锌源蛋鸡产蛋性能、直肠温度、血清IL 1β以及肝脏和脾脏组织MT和锌含量的影响。结果表明,日粮锌源以及锌源与LPS互作对蛋鸡的产蛋率、蛋重和破蛋率均没有显著影响(P> 0.05),LPS攻毒显著降低产蛋率(P< 0.05)并增加破蛋率(P< 0.05),其中添加氨基酸络合锌(ZnAA)蛋鸡的产蛋率显著(P< 0.01)低于基础日粮组;饲喂ZnAA的蛋鸡LPS攻毒后直肠温度峰值出现以及发热消退的时间均早于添加ZnSO4和不添加锌的蛋鸡。饲喂ZnAA的蛋鸡注射LPS 3 h后血清IL 1β的水平显著高于饲喂ZnSO4 的蛋鸡,而注射LPS 12 h后血清IL 1的水平则显著低于硫酸锌组(P< 0.05)。与ZnSO4 相比,添加ZnAA具有提高注射LPS后肝脏和脾脏组织锌浓度的趋势(P< 0.09)。锌源和LPS应激以及两者的互作显著影响组织金属硫因(MT)的含量(P< 0.001),在LPS应激蛋鸡中,添加ZnAA的蛋鸡肝脏和脾脏MT的水平显著高于添加ZnSO4 的蛋鸡(P< 0 001):与饲喂基础日粮的蛋鸡相比,添加ZnAA蛋鸡肝脏和脾脏MT浓度分别提高266%和225%,而添加ZnSO4仅提高158%和151%。由     

Effect of excess dietary threonine on laying performance,egg quality,serum free amino acids,and digestive enzymes activities of laying hens during the postpeak period

A total of 640 layer hens, 56 wk of age, were allocated to 4 dietary treatments groups, each of which included 5 replicates of 32 hens. Graded levels ofl-Thr were added to the basal diet at 0.0 (control), 1.0, 2.0, and 3.0 g/kg; determined Thr values were 5.7, 6.5, 7.4, and 8.7 g/kg of diet, respectively. In the 53-d feeding trial, egg production increased significantly due to dietaryl-Thr supplementation. Hens fed 2.0 g of Thr/kg of diet had significantly higher egg production than the control diet. Supplementing the diet withl-Thr did not affect egg weight or feed intake, but egg mass increased significantly. Also, FCR was improved significantly and the best FCR was exhibited by hens receiving 2.0 g of Thr/kg of diet. Feeding laying hens a diet containing 2.0 g ofl-Thr/kg of diet improved Haugh units linearly; however, egg shell thickness decreased linearly as the level of dietary Thr increased, and the lowest value was observed for hens fed 3.0 g of Thr/kg of diet. Serum free Thr increased linearly as supplemental Thr increased, but serum free Ile, Phe, and Tyr decreased. No differences attributable tol-Thr were found among groups in the activity of digestive enzymes (trypsin and amylase) in the mucosal homogenates of the jejunum. The activity of α-alkaline phosphatase in the jejunum was analyzed as a marker of mucosal enterocyte maturation and no differences due tol-Thr supplementation were noted. In conclusion, feeding laying hens from 56 to 64 wk of agel-Thr up to 2.0 g/kg can improve laying performance and Haugh units.     

Comparison of the fast‐induced and high dietary zinc‐induced molting: trace elements dynamic in serum and eggs at different production stages in hens (Gallus domesticus)

A number of 252, 70 week old, single comb white leghorn hens at the end of their first production cycle were divided into two groups: group‐I; molted by fasting and group‐II; by high dietary zinc to obtain the second and third production cycle. Sampling was carried out at 5%, peak and end of the second production cycle and at 5% and peak of the third production cycle. Serum zinc decreased at the peak of the second production cycle, while increased at the 5% of the third production cycle in zinc‐molted group. Serum copper and manganese increased at the 5% and peak of the second production cycle in zinc‐molted group. Egg albumin zinc and copper increased at the 5% and peak of the second as well as third production cycles in zinc‐molted group. Egg albumin manganese increased at 5% during the second production cycle in fasting molted group. Egg yolk zinc increased at the peak of the second production cycle in zinc‐molted group. Egg yolk copper increased at the 5% of second production cycle but decreased during the third production cycle in zinc‐molted group. Egg yolk manganese increased at the 5% and at the end of the second production cycle in zinc molted group. Egg yolk manganese and iron decreased during the third production cycle in zinc‐molted group. Eggshell zinc decreased at the end of the second production cycle in the zinc‐molted group, while eggshell copper increased at the peak of the second as well as third production cycles in fasting molted group.     

高铁高碘日粮对蛋品质的影响

用高铁高碘日粮饲喂产蛋母鸡,观察对蛋品质的影响。结果表明,蛋黄重、蛋黄占蛋重比略有下降,蛋白占蛋重比、哈夫单位有所上升;蛋壳占蛋重比、蛋壳厚度及蛋壳密度无明显变化。提示高铁高碘日粮不会引起蛋品质的明显下降。