光照周期和饲喂水平对蛋鸡卵巢和输卵管形态发育的影响

为研究光照周期和限饲对蛋鸡卵巢和输卵管发育及形态学的影响,选用体质健康的10周龄海兰灰蛋鸡240只,采用3×2双因子设计,分别在短光照周期(8L∶16D),中长光照周期(12L∶12D)和长光照周期(16L∶8D)下采取自由采食(对照)和限饲(自由采食量的80%)处理,共计6个组,分别为短光照对照组(Ⅰ)、短光照限饲组(Ⅱ)、中长光照对照组(Ⅲ)、中长光照限饲组(Ⅳ)、长光照对照组(Ⅴ)和长光照限饲组(Ⅵ),每组4个重复,每个重复10只鸡。结果显示:1光照周期显著影响14周(w)卵巢单位面积内卵泡数量(P0.05)及18 w卵巢卵泡直径(P0.05),短光照周期组卵巢单位面积内卵泡数量显著高于中长光照周期组(P0.05);短光照周期的卵巢卵泡直径显著高于中长光照周期和长光照周期组(P0.05);2饲喂水平显著影响14 w卵巢重及18 w卵巢卵泡直径(P0.05),Ⅲ组卵巢重显著高于Ⅳ组(P0.05),3个对照组18 w卵巢卵泡直径分别显著高于其限饲组(P0.05);3光照周期与饲喂水平的互作对18 w卵巢卵泡直径及18 w卵巢单位面积内卵泡数量影响显著(P0.05);43个对照组输卵管皱褶发育均匀,皱褶长度,厚度明显优于其限饲组。     

光照周期对蛋鸡性成熟性状的影响

为了研究光照周期对蛋鸡性成熟的影响,将160只健康海兰褐蛋鸡随机分为4个处理组,每个处理组设4个重复,每个重复10只鸡。10周龄到19周龄末控制光照周期为8L∶16D,采用大群饲养管理;从19周龄开始,每个重复随机抽取2只鸡单笼饲养以便指标测定;20周龄开始增加光照,光照周期分别为17L∶7D(Ⅰ组)、15L∶9D(Ⅱ组)、13L∶11D(Ⅲ组)、11L∶13D(Ⅳ组)。试验结果表明:光照周期对蛋重、卵巢重、大黄卵泡个数及重量,小黄卵泡个数及重量、输卵管长度及重量、鸡冠重、肉髯重、腹部容积、耻骨宽度、龙骨长、小腿胫粗度影响差异不显著(P>0.05);处理组Ⅰ和Ⅳ相比,对开产日龄的影响有显著差异(P<0.05),和其他组相比差异不显著。处理组Ⅰ与Ⅱ、Ⅳ组对跖长影响差异显著(P<0.05)。     

不同光照周期对蛋鸡高峰期血液激素水平的影响

将320只10周龄海兰褐商品蛋鸡,随机分为8组,每组4个重复,每个重复10只鸡。采用渐增和骤增两种增光方式,光照周期设11L;13D、13L;11D、15L：9D、17L：7D4个水平。29周龄末,每个重复随机抽取2只鸡单笼饲养,每隔2h采1次血,测定FSH、LH、P4和E2水平。结果表明：FSH和LH协同能促进卵泡成熟,促进卵巢分泌E2和P4,并引起排卵。以缓增,光照周期为11L：13D（处理组11）组的FSH、LH峰值含量最高;激素分泌规律性并不和光照周期长短呈正相关     

光照周期对蛋鸡生产性能影响的研究进展

蛋鸡对光照周期的变化极为敏感,适宜的光照周期可使蛋鸡达到最佳生产性能,不良的光照周期对蛋鸡的生产性能会产生负面影响,降低经济效益。文章综述了近年来有关光照周期对蛋鸡生产性能影响的研究进展,并结合光照周期对蛋鸡生产性能的作用机理,阐述了实际生产中通过调节光照周期提高蛋鸡生产性能的措施。     

光照对蛋鸡产蛋率的影响

产蛋鸡对光照的反应比较敏感，光照时间的长短、强度的强弱直接影响到产蛋率，因此在整个产蛋周期要有一个适当的光照制度，以满足产蛋鸡对光照的需要，否则就会受到一定的经济损失。曾有一病例，由于光照时不足，引起产蛋量下降。现陈述如下：     

光照周期对蛋鸡高峰期蛋品质的影响

鸡具有敏感的视觉反应,因而光照对禽类来讲是最重要的生态因子之一.在蛋鸡产蛋期的光照管理上,日光照时数一般认为以14～16 h为宜.Ciaceiariell M等[1]报道,当光照时数为11～12 h时,蛋鸡可以有最佳的产蛋性能.     

利用自动监测系统研究光照周期对蛋鸡摄食行为的影响

本试验利用自动监测系统研究光照周期对蛋鸡摄食行为的影响。220日龄海兰灰商品蛋鸡36只,随机分为3组,8L∶16D光照处理组(8∶00～16∶00),12L∶12D光照处理组(6∶00～18∶00)和16L∶8D光照处理组(0∶00～16∶00),每组3个重复,每个重复4只鸡,密闭式鸡舍单笼饲养,研究不同光照周期对蛋鸡采食、饮水、排泄行为的影响。结果表明:光照周期对采食、饮水和排泄有显著影响,在有光期各试验组采食量、饮水量、排泄量曲线变化明显,在黑暗期采食量、饮水量和排泄量变化趋势平稳。8L∶16D、12L∶12D和16L∶8D光照处理组采食量分别为115.32g、119.41g和125.04g,饮水量分别为196.01g、218.68g和236.02g,排泄量分别为124.00g、131.79g和145.19g,采食与饮水量之比分别为1∶1.70、1∶1.83和1∶1.89,采食量与排泄量之比分别为1∶1.08、1∶1.10和1∶1.19。     

不同能量水平对广西三黄母鸡育成期体重及生殖器官的影响

为研究不同能量水平对广西三黄母鸡育成期体重及生殖器官的影响。采用单因子随机分组试验设计,饲粮代谢能设6个水平,分别为每千克10.5、10.9、11.3、11.7、12.1、12.5 MJ。将1 152只体重差异不显著的7周龄健康三黄鸡后备种母鸡随机分成6个处理,每个处理4个重复,每个重复48只,全期84天。结果,在限饲条件下,饲粮代谢能水平对体增重、体重均匀度、卵巢重量和输卵管长度有极显著或显著影响。随着日粮代谢能水平的提高,后备鸡的体重、增重、卵巢重量和输卵管长度也逐渐增加,而体重均匀度则以中代谢能水平组为最好。从本次试验看代谢能水平为11.7 MJ/kg可作为配制广西三黄鸡后备母鸡饲粮代谢能水平的参数。     

光照对蛋鸡的影响与不同时期蛋鸡的光照管理

鸡的眼睛通过对光照时间的长短或强弱的感受后,经神经传导而刺激其脑下垂体产生促卯泡素,促进排卵和产蛋。如果没有足够的光照刺激,不可能充分发挥鸡的产蛋遗传能力。经常看到冬天农村散养鸡基本不产蛋,或者产蛋很少,其原因除天气寒冷外,主要因素是冬季昼长夜短。因此,对于大规模的集约化养鸡专业户来说,必须要制定光照管理制度和程序,给鸡进行人工补充光照,才能保证高的产蛋率,获得好的养殖效益。     

光照周期影响家禽卵巢机能的研究进展

光照周期是禽类繁殖性能的重要影响因素之一,研究光照周期对家禽造成的氧化损伤及对卵巢机能的影响,阐明光照周期调控卵巢机能的机制,是目前家禽养殖行业亟需解决的问题之一。文章综述了光照周期影响禽类卵巢机能的研究现状,为开展禽类繁殖过程中光照周期的影响调控机制研究奠定了理论基础。     

Effects of photoperiod on broodiness,egg-laying and endocrine responses in native laying hens

1. The effects of photoperiod on broodiness, egg-laying and endocrine responses in native laying hens were investigated. A total of 648, 18-week-old native laying hens (Beijing You Chicken, BYC) were randomly allocated to 6 groups with 3 replicates. The birds were exposed to 1 of 6 different photoperiods, including 16L:8D (06:00 to 22:00 h) for group 1; 12L:2D:4L:6D for group 2; 8L:4D:4L:8D for group 3; 16L:8D (03:00 to 19:00 h) for group 4; 14L:10D for group 5; and 18L:6D for group 6.

2. The broodiness rate and egg-laying rate for weeks 20–26, 27–33, 34–40, 41–47, 48–54 and 55–61 were calculated, and serum prolactin (PRL), luteinising hormone (LH), 17-beta-oestradiol (E2), melatonin (Mel) and progesterone (P4) concentrations were measured at the end of each stage.

3. Significant effects were observed on the rate of broodiness by the photoperiod and stage, but the interaction of photoperiod and stage was not significant. The rate of broodiness for group 3 (5.9%) was significantly higher than other groups, with group 2 being the lowest (2.8%). Broodiness rate was the highest for weeks 41–47 (9.9%). Significant effects were observed on average egg-laying rate by photoperiod and stage: the rate of egg-laying of groups 2 and 5 were significantly higher than groups 1, 4 and 6.

4. There were no significant effects of photoperiod on PRL, LH and Mel concentrations at 26, 33, 40 and 54 weeks of age (P > 0.05), but at 47 weeks of age, PRL and LH concentrations of group 1 were significantly lower than those in other groups.

5. The study suggests that the photoperiod of group 2 (12L:2D:4L:6D) is optimal for the birds’ performance to give the lowest broodiness rate and the highest egg-laying rate during the whole laying period, and 41–47 weeks may be a key stage for the photomodulation of broodiness.     

日粮维生素水平对生长期蛋鸡影响的研究

选用4因素3水平正交试验设计，研究日粮维生素A、D3、E对生长期蛋鸡的影响。结果如下：6周末体重随VE水平的提高而提高，但差异不显著。14周末体重受VE的显著影响。高水平（100mg／kg）组显著大于低水平（10mg／kg）组与中水平（40mg／kg）组（P＜0．01），中、低水平之间差异不显著。血清新城疫抗体效价随VA水平的提高而显著提高（P＜0．05）。高水平VA和高水平VE组合组显著高于其它组（P＜0．05）。胫骨中的钙含量随VA水平的提高显著提高（P＜0．01）。VD3对体重、抗体滴度和胫骨Ca含量无显著影响。     

Effects of phyto‐oestrogen quercetin on productive performance,hormones, reproductive organs and apoptotic genes in laying hens

Quercetin, a polyphenolic flavonoid with diverse biological activities including anti‐inflammatory and antiviral, inhibits lipid peroxidation, prevents oxidative injury and cell death. The purpose of the research was to investigate the effect of quercetin on productive performance, reproductive organs, hormones and apoptotic genes in laying hens between 37 and 45 weeks of age, because of the structure and oestrogenic activities similar to 17β‐oestradiol. The trial was conducted using 240 Hessian laying hens (37 weeks old), housed in wire cages with two hens in each cage. These hens were randomly allotted to four treatments with six replicates, 10 hens in each replicate and fed with diets containing quercetin as 0, 0.2, 0.4 and 0.6 g/kg feed for 8 weeks. The results showed that dietary quercetin significantly increased (p < .05) the laying rate and was higher in group supplemented with 0.4 g/kg, and feed‐egg ratio was decreased (p < .05) by quercetin. Dietary quercetin has no effect (p > .05) on average egg weight and average daily feed intake. Compared with control, secretion of hormones, oestradiol (E₂)_, progesterone (P4), follicle‐stimulating hormone (FSH), luteinizing hormone (LH), insulin‐like growth factors‐1 (IGF‐1) and growth hormone (GH), was found to be significantly higher (p < .05) in quercetin‐supplemented groups. Also ovary index, uterus index and oviduct index were not significantly influenced (p > .05) by quercetin, whereas magnum index, isthmus index, magnum length, isthmus length and follicle numbers were significantly increased (p < .05) with quercetin supplementation. Additionally, expression of apoptotic genes was significantly (p < .05) up‐regulated or down‐regulated by quercetin. These results indicated that quercetin improved productive performance, and its mechanism may be due to the oestrogen‐like activities of quercetin.     

调节胚胎代谢对蛋鸡激素、抗氧化及产蛋性能的影响

应用VE、VC及普鲁卡因作为胚胎调节剂对蛋鸡胚胎生长发育进行调控。225枚种蛋随机分为3组,即对照组,不采取任何处理;试验1组,采用（78%VE14μL＋25%VC20μL）/枚;试验2组,采用（78%VE14μL＋25%VC20μL＋2%普鲁卡因56μL）/枚;于入孵前,距离种蛋钝端1/4近气室处,经酒精消毒,将调节剂液注射到种蛋胚盘附近,探讨其对蛋鸡内分泌水平、抗氧化性能、免疫性能及生产性能的影响。结果表明：与对照组相比,15周龄蛋鸡激素水平,1组卵泡刺激素（FSH）、促黄体生成素（LH）水平均极显著提高（P〈0.01）;2组甲状腺素（T4）水平显著提高（P〈0.01）。39周龄时,1、2组T4水平显著升高（P〈0.05或P〈0.01）,2组孕酮（P）、胰高血糖素水平显著提高（P〈0.05）;抗氧化性能,试验组血清和肝脏中丙二醛（MDA）含量均不同程度地降低,其中2组血清MDA显著降低（P〈0.05）,其余指标差异不显著;脂类代谢方面,试验2组蛋黄胆固醇降低16.58%（P〈0.05）,1组蛋黄粗脂肪降低13.51%（P〈0.05）。对新城疫（ND）疫苗免疫的影响,试验组在注射ND疫苗后7、14、28 d抗体效价不同程度地提高,其中1组在14、28 d时抗体效价差异极显著（P〈0.01）。此外,0 d,1组的抗体效价比2组提高58.35%,差异显著（P〈0.05）;28 d,1组的抗体效价比试验2组提高29.03%（P〈0.01）;其他时间点2个试验组间差异不显著。在22~39周龄,试验1、2组平均蛋重和总产蛋量都不同程度地提高,1组尤为显著（P〈0.01或P〈0.05）,而试验组料蛋比均显著性降低（P〈0.05）。因此,通过调节胚胎代谢能明显改善出壳后蛋鸡的内分泌水平及抗氧化性能,提高产蛋性能。     

Restricted feeding time and the behaviour of caged laying hens

1. Layers housed as pairs in cages were denied access to food from 07.30 to 15.30 h each day. Analyses of video records of daily activity patterns showed several behaviour changes compared with the patterns shown by similar birds allowed ad libitum (AL) access to food. 2. Birds given restricted access (RA) to food spent more time sitting and cage pecking while unable to feed than those feeding ad libitum during the same period. They also engaged in less agonistic pecking and the lengths of bouts of drinking were reduced during the period of food denial compared with the AL treatment. 3. After the food troughs were uncovered birds on the RA treatment showed fewer bouts of feather pecking but more bouts of drinking than the AL treatment. 4. Improvements previously reported in the efficiency of food utilisation of birds on the RA treatment may have been the result of additional sitting, although other activities requiring energy expenditure were performed. 5. It is concluded that restricting access to food on a time basis has both positive and negative effects on the welfare of caged layers.     

Effects of feeding on the plasma disposition kinetics of the anthelmintic albendazole in laying hens

1. To optimise the use of albendazole (ABZ) as an anthelmintic in hens, the effects of fasting and type of diet on the plasma kinetics of ABZ and its metabolites were evaluated.

2. Twenty-four hens were distributed into 4 groups: In experiment I the Fed group were fed ad libitum, while the Fasted group was fasted over a 12-h period. In experiment II the Pelleted group was fed with pelleted commercial food, while the Grain group was fed with cereal grains. All the groups were treated with ABZ by oral route. Blood samples were taken and plasma analysed by HPLC.

3. ABZ and its metabolites albendazole-sulphoxide (ABZSO) and albendazole-sulphone (ABZSO₂) were recovered in plasma in all the groups. The 12-h fasting period did not modify the disposition kinetics of ABZ in hens. The type of feed affected ABZ kinetics. ABZSO concentration profile was higher and detected for longer in the Grain group compared to the Pelleted group. Statistical differences were not found for AUC_0-∞ values, whereas the T_1/2for and T_1/2el were different between groups.

4. Factors affecting ABZ kinetic behaviour should be taken into account to optimise its use to ensure the sustainability of the limited available anthelmintic therapeutic tools in avian parasite control.     

Isolation of infectious bronchitis virus from intestine and reproductive organs of laying hens with dropped egg production

A total of 52 samples (22 cloacal swabs and 30 pooled ovaries and oviducts) from hens with a history of a 25 to 40% drop in egg production from 30 flocks were examined for the isolation of infectious bronchitis virus in embryonated chicken eggs. Five isolates were obtained: three from cloacal swabs and two from reproductive organs. These isolates were identified and characterized on the basis of agar-gel-precipitation, hemagglutination, and neutralization tests and other physicochemical characteristics.     

Effects of changes in photoperiod and feeding opportunity on the performance of two breeds of laying hen

1. ISA Brown and Shaver 288 hens, fed ad libitum, were given a 5‐h increase or a 2, 5 or 10‐h decrease in photoperiod at 215 d of age. Hens of both breeds were also maintained on constant 10, 13 or 18 h photoperiods. Other groups had their photoperiod increased from 8 to 13 h, or were held on constant days but had their access to food limited to 8 h per day.

2. Both breeds on ad libitum feeding exhibited curvilinear rate of lay and egg output, and linear food intake, responses to photoperiod change. Shaver hens reduced their egg output and rate of lay to a greater extent than ISA Brown hens when photoperiod was decreased.

3. In both breeds the beneficial effect on egg production of the 5‐h increase in photoperiod was less than the adverse effect of the 5‐h decrease.

4. The influence of light change per se generally had a greater effect on performance than the influence of feeding opportunity, but significant effects of changing feeding opportunity were demonstrated.

5. The reduction in mean rate of lay and egg output following a reduction in photoperiod was partly caused by some birds ceasing lay, but all birds showed some decrease in both variates     

多种维生素“嘉利补”对蛋种鸡生产性能和抗体水平的影响

本试验旨在研究嘉利补对蛋种鸡生产性能的影响。选取160日龄海兰灰父母代蛋种鸡1200只,随机分为2个处理,每个处理3个重复。采用单因素随机试验设计。试验组在基础日粮中添加2g/kg嘉利补,对照组饲喂基础日粮,试验期24d。结果表明:添加嘉利补组蛋种鸡产蛋率和蛋黄相对重较对照组分别提高4.83%(P0.05)和8.97%(P0.05);料蛋比、破蛋率和淘汰率分别降低6.40%(P0.05)、22.50%(P0.05)和21.28%(P0.05);免疫后14d和28d,抗体滴度分别提高2.86%(P0.05)和10.70%(P0.05);受精率和受精蛋孵化率均高于对照组;试验末平均每只蛋种鸡每天多获利0.13元。