饥饿法阶段控制体重对蛋鸡强制换羽的探究

采用饥饿法阶段控制体重对蛋鸡实行强制换羽，体重管理控制在90％以下维持33d，85％以下维持16d，85％～75％维持6d。换羽期75日龄内死亡率为2％，第二个产蛋期的平均产蛋率为66．68％，平均蛋重60．27g／枚，每只鸡平均产蛋8．56kg，纯收入7．07元。采用饥饿法阶段控制体重组的各项生产性能指标明显高于体重下降至75％开料组和饲喂2％高锌饲料组．为养鸡利用第二个产蛋周期提供了实践指导和科学依据。     

不同粗蛋白水平日粮对产蛋鹌鹑生产性能的影响

本文本试验采用三个粗蛋白水平，研究了不同粗蛋白水平日粮对产蛋鹌鹑生产性能的影响，试验结果表明三个日粮的饲养日产蛋率分别为７５．３％，７８．２％，８５．４％，差异极显著。三组的饲料转化效率分别为３．３１，３．１５，２．６９，差别十分明显。产鹌对日粮蛋白水平的需要不低于１９，８％，日粗蛋白质需要量不低于４．８克。日粮水平越低，产蛋高峰维持的时间越短；粗蛋白水平越高，产蛋高峰维持的时间越长。     

黄羽鹌鹑生产性能观察

对第二世代黄羽鹌鹑生长、生产性能进行观测的结果，公母１∶３的配种比例情况下，种蛋受精率８８．６％，受精蛋孵化率８４．５％，健雏率９６．５％，育雏成活率９７％。平均蛋重１１．４３ｇ，试验期平均产蛋率８４．７％。３００日龄每鹑产蛋２１２个，料蛋比２．６８∶１。两周龄体重平均４７．７５ｇ，成年体重略轻，公鹑１１４．０６ｇ，母鹑平均为１４３．６３ｇ。     

蛋鸡人工强制换羽好处多

<正> 我于1982年3月7日育雏125只,育成产蛋母鸡67只,12月中旬产蛋率达84％,高产期过后,在1983年8月初低产母鸡开始换羽休产,产蛋率下降到50％左右。为使鸡群集中换羽休产,尽快结束第一个产蛋期,争取第二个产蛋期提前到来。我于1983年8月16日对自家养的产蛋母鸡采取了15天绝食期的人工强制换羽措施。做法如下: 从母鸡群中挑出平均体重以下的、体质弱的8只母鸡不搞强制换羽,1—3天停料、断水,第四天开始给饮水,仍然停料绝     

二十四小时断食和限食做为产蛋母鸡诱导换羽的方法

用短期断食和喂饲低蛋白低热量＂换羽料＂的新换羽方法与断食８天的传统换羽方法和非换羽母鸡做比较．供试的新换羽方法包括２８天自由采食、每日限食或隔日限食换羽料。记录了从开始换羽起共３１周（４周换羽．１周预备产卵和换羽后２６周）的产蛋量、蛋重、比重、体重、采食量和死亡率。比较不同换羽方法母鸡的饲料成本、蛋价值，平均每只入舍鸡扣除饲料成本的毛利润等各种经济变量．能自由采食换羽日粮的母鸡比用其它方法换羽的母鸡在换羽期间产出更多的蛋．就总产蛋量和收益（卖蛋价值减饲料成本）在各换羽方法间的比较结果相差不大．但高于非换羽的对照组．非换羽对照组收益为２．２０美元，传统换羽方法组为２．８７美元，自由采食组为２．９２美元，每日限食组为２．８１美元．隔日限食组为２．９７美元，这个结果说明，新的换羽方法包括２４小时或不足２４小时的短时间断食与传统的长时间断食具有同样的经济效果。     

褐壳蛋鸡饥饿法强制换羽的研究

４８００余只５０７日龄海兰褐商品蛋鸡实施饥饿法强制换羽,结果：试验鸡群６０日龄内死淘率为３．４６％,换羽后产蛋高峰８７％８０％以上产蛋率维持了８９ｄ,平均蛋重６６．１ｇ／个,高峰期只鸡日产蛋５７ｇ,换羽后蛋壳质量有了明显好转。褐壳蛋鸡饥饿法强制换羽的...     

蛋鸡第二产蛋期的利用技术

蛋鸡第二产蛋年的产蛋率和产蛋数量均较第一产蛋年低，但可节省购买雏鸡、育雏、育成的费用，而且第二产蛋年产蛋时蛋鸡抗病力较强，死亡率较低，喂养时料蛋比相差不大，综合来说，经济效益还是较可观的。现将蛋鸡第二产蛋年的利用技术介绍如下。１．强制换羽早产蛋强制换羽比自然换羽提前３～４周产蛋。方法有两种：一是饥饿法：鸡的产蛋率下降到３０％左右时，停止人工补充光照，停料７天左右，不停水；以后９～１０天内每只鸡每天给料３０～４０克；然后自由采食蛋鸡饲料。此法换羽掌握鸡体失重２０％～３０％为宜。二是化学法：鸡群中有…     

夏季蛋鸭强制换羽技术

盛夏时节，鸭群经过春季第一个产蛋高峰后，相继进入生理上的换羽休产期，产蛋率迅速下降，蛋形变小甚至出现畸形蛋。此时如果任其自然换羽，不但换羽期持续期可长达４个多月，而且换羽时间参差不齐，将坐失秋季第二个产蛋高峰良机，严重影响养鸭收入。我地一些有经验的养鸭户，每天夏季鸭群产蛋率降至３０％以下时，对鸭群进行人工强制换羽，从而实现整个鸭群的高产稳产。根据我地养鸭户的经验，只要按照以下三个阶段操作，就会顺利实现人工换羽。１强制关养把鸭群关在棚舍内３～４天，在此期间不放牧、不喂料，只是每天上午放出到水上运动…     

3种强制换羽法和2种日粮处理提高蛋鸡生产性能试验

对４００日龄罗曼商品代蛋鸡用３种强制换羽方法和２种日粮配方对比试验，可明显提高其生产性能和经济效益。３个强制换羽组１５３ｄ个体平均产蛋率分别为５５．８３，６０１．５％和６２．８５％，第三组最高日产蛋率达８７．６２％。２种日粮组全期平均产蛋量分别为６０５３．３４ｇ和６１３８．５０ｇ，饲料费用分别为３１．６３地和２９．８０元，Ｂ组比Ａ组盈利高５５．３２％．     

海兰蛋种鸡的强制换羽

一、材料与方法１．试验时间和地点：长治市种鸡场，２０００年２月４日开始。２．试验品种：海兰蛋种鸡，６６周龄（４６２日龄）。３．换羽前准备工作：（１）调整鸡群：淘汰病、弱、残、过肥、过瘦的鸡，移位并笼。（２）免疫接种：强制换羽前２周全群进行加强免疫，新城疫、传染性支气管炎、传染性囊病三联疫苗颈部皮下注射。（３）驱虫：强制换羽前７天用盐酸左旋咪唑驱虫。（４）抽样称重：第一期产蛋临近结束即第６５周龄（４５５日龄）时进行。上午空腹称重，随机抽１５０羽作样本，计算平均体重作为基础体重。（５）饲料药品：准备…     

葡萄籽粕替代玉米对种鸡产蛋高峰后期生产性能、鸡蛋品质及新城疫抗体水平的影响

试验旨在研究葡萄籽粕对种鸡产蛋高峰后期生产性能、鸡蛋品质及新城疫抗体水平的影响。选取产蛋率、体重相近,健康状态良好的64周龄罗曼灰父母代种鸡810只,随机分为6组,每组5个重复,每个重复27只鸡。对照组饲喂基础日粮,试验组分别饲喂葡萄籽粕替代基础日粮中3%、4.5%、6%、7.5%、9%玉米的试验日粮（分别为试验Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ组）。预试期7 d,正试期30 d。探讨日粮中添加不同水平的葡萄籽粕对种鸡产蛋高峰后期生产性能、鸡蛋品质及新城疫抗体水平的影响及其作用机理。结果表明：葡萄籽粕能够明显抑制种鸡产蛋高峰后期生产性能降低,对于日均产蛋量,试验Ⅲ组极显著高于对照组（P<0.01）,试验Ⅰ、Ⅱ组显著高于对照组（P<0.05）;试验Ⅰ、Ⅱ、Ⅲ组产蛋率较对照组分别提高了12.38%、14.76%、18.09%（P<0.05）,各试验组蛋鸡的日均采食量、料蛋比及破软蛋率与对照组相比差异不显著（P>0.05）;葡萄籽粕处理组鸡蛋的哈氏单位、蛋黄重及蛋壳强度均高于对照组,但随葡萄籽粕添加量的增加没有表现出规律性变化;葡萄籽粕能够降低鸡蛋胆固醇含量（P<0.01）;并能够提高种鸡新城疫HI抗体水平（P>0.05）。综上,在种鸡产蛋高峰后期日粮中以葡萄籽粕替代玉米,可提高种鸡生产性能和新城疫抗体效价,改善鸡蛋品质,降低鸡蛋中胆固醇含量,且以替代6%的玉米效果较好。     

外源肌苷酸对种鸡产蛋性能、蛋品质及种蛋孵化性能的影响

本试验通过在种鸡的基础饲粮中加入肌苷酸（IMP）来研究其对种鸡产蛋性能、蛋品质和种蛋孵化性能的影响。选择遗传背景相同、体重相近,产蛋率达到5%的20周龄健康AA种鸡864羽,随机分为2组（对照组饲喂基础饲粮;试验组饲喂基础饲粮＋0.5%肌苷酸）,每组6个重复,每个重复72羽,试验期30 d。测定试验期间所有种蛋的平均蛋重、产蛋率和合格蛋率;每组随机选取部分种蛋进行蛋品质测定;于孵化开始第17天,通过照蛋处理统计种蛋受精率,第21天出雏时,计算受精蛋孵化率、入孵蛋孵化率和健雏率。试验结果表明：与对照组相比,试验组种鸡的平均蛋重、产蛋率和合格蛋率均有升高的趋势,但差异不显著（P>0.05）;蛋形指数显著升高（P<0.05）,蛋壳强度、蛋壳厚度和蛋黄颜色显著降低（P<0.05）;受精率、受精蛋孵化率和入孵蛋孵化率显著升高（P<0.05）,健雏率和雏鸡体重有升高的趋势,但差异不显著（P>0.05）。综上,0.5%外源肌苷酸对种鸡的产蛋性能和种蛋孵化性能均有促进作用。     

柱花草粉对蛋鸡生产性能及蛋品质的影响

 选取健康35周龄海兰褐蛋鸡450只,随机分为5组,每组90只。分别在饲粮中添加0%、2%、4%、6%、8%的柱花草粉,进行饲养试验,试验期90 d。在试验期间测定不同比例的柱花草粉对蛋鸡生产性能及蛋品质的影响。试验结果表明,4个添加不同比例柱花草粉的试验组蛋鸡的生产性能均显著高于没有添加柱花草粉的对照组;添加6%柱花草粉效果最佳,较对照组产蛋率平均增加15.75%,蛋重平均增加1.71%,料蛋比降低5.51%,死淘率降低10%,对蛋形指数、蛋黄相对重、蛋壳相对重、哈夫单位值均无显著影响。     

Effect of temporary transfers to 14 h on age at first egg in domestic pullets reared on 8-h photoperiods

1. Brown-egg pullets were reared on 8-h photoperiods and temporarily transferred at 80 d of age to 14-h photoperiods for 2, 4, 6, 8, 10 or 12 d. Controls were either maintained on 8 h or permanently transferred to 14 h at 80 d. 2. Pullets given 8 or 12 long days matured 8-9 d earlier than constant 8-h controls, but 22-23 d later than pullets transferred permanently to long days. Mean age at first egg for the groups given 2, 4, 6 or 10 d of 14-h days were not significantly different from the 8-h controls. The mean weight of first egg and body weight at first egg for the temporarily-photostimulated groups were not significantly different from constant 8-h controls, but egg weights were > or = 5.1 g and body weights at first egg > or = 200 g heavier than the birds transferred permanently to 14 h. 3. It is concluded that up to 6 temporary long days may be given (from 80 d of age) without affecting the timing of sexual maturity, but that the provision of 8 or more long days will accelerate sexual development, thought not to the extent of a permanent transfer, in most birds within a flock. A regression analysis of the ages at which the first and last birds in the groups given 6, 8, 10 or 12 long days matured suggested that about 20 d of photostimulation are required to achieve a mean age at first egg similar to that of birds permanently transferred to long days.     

蛋鸡强制换羽试验效果初报

强制换羽技术已在现代养禽业中被广泛运用。2012年9月至2013年1月某鸡场对一批罗曼蛋鸡进行了强制换羽试验,通过实施强制换羽,复产后产蛋高峰来得整齐,获得理想的第二个产蛋周期,前后三个月平均值相比种蛋合格率提高31.3%、蛋重提高16.3%、受精率提高12.3%、孵化率提高18%、出壳重提高11.7%,节约培育费用,延长种鸡经济利用期,一定程度上回避了经营风险。     

Selection with restriction in a poultry breeding scheme with different selection procedures in both sexes: direct responses

1. A selection experiment with two lines of White Leghorns originating from a common base population was carried out over 5 generations with the aims of maintaining an unchanged egg weight, reducing age at first egg and reducing adult body weight. Each line consisted of 14 male and 42 female breeders. 2. Males were mass selected for low body weight at 20 weeks of age. To compensate for the expected correlated loss in egg weight, hens were selected according to an index which counteracted this undesirable change while also reducing age at first egg and reducing body weight. 3. An index value was calculated for each individual hen from average egg weight, age at first egg and body weight at 20 weeks. Index weights had to be calculated for each generation and line in accordance with the expected change in egg weight due to male selection on body weight. 4. For control matings hens with an index near the population average were mated either to males with body weight near the population average (control C1) or to the selected males within lines (control C2). 5. Expected and observed total responses agreed well for all traits in line 1 and for body weight in line 2. 6. Phenotypic variances and covariances showed little change during the experiment. However, genetic variances and covariances estimated at the end of the experiment showed some differences, both between lines and compared to the parameters used for index construction.     

Changes in the body condition scores of Nigerian West African Dwarf sheep experimentally infected with mixed infections of Haemonchus contortus and Trichostrongylus colubriformis

Weekly changes in body condition scores and body weights were determined in West African Dwarf sheep following trickle exposure to weekly escalating mixed infections with Haemonchus contortus and Trichostrongylus colubriformis starting with single doses of 500 infective larvae (L(3)) at wk1, 1000 L(3) at wk2, 2000 L(3) at wk3 and 4000 L(3) at wk4. Thirty-three animals were randomly assigned to two groups namely, Group 1 (n=27) and Group 2 (n=6). Group 1 animals were used for experimental infections and Group 2 animals served as uninfected controls. Body condition scores (BCS), body weights (BW), faecal egg counts (FEC) per gram of faeces and worm burden (Wb) were determined using standard procedures. Lambs in group 1 with epg ≤ 1000 were classified as strong responders (n=16), those with epg between 1000 and 10,000 as intermediate (n=5) and lambs with epg>10,000 on any sampling day were classified as weak responders (n=6). Based on this classification, the mean epg of lambs classified as strong responders was significantly lower (P<0.001) than the epg of lambs classified as weak responders. The body condition scores and body weights of the strong responder lambs were comparable with those of the uninfected control and they were significantly higher than those of the weak and intermediate responders from wk5 till the end of the experiment. There was an inverse and significant relationship between the average BCS of days 56 and 59 and the average FEC of days 56 and 59 (r(s)=-572; P=0.017; n=27) as well as with Wb (r(s)=-531; P=0.028; n=27). We concluded that changes in the body scores are good indicators of the intensity of gastrointestinal nematode infection in the Nigerian WAD sheep.     

肉牛改良蒙古牛效果分析

上世纪70年代以来锡林郭勒盟先后引进安格斯、利木赞、夏洛来、西门塔尔等肉牛品种改良蒙古牛.分析测定了不同品种杂交一代公母牛及蒙古牛6月龄、18月龄和30月龄体重的变化规律.结果安蒙、利蒙、夏蒙、西蒙杂一代6月龄公母犊平均体重分别比同龄蒙古牛增加37.87 kg、40.60 kg、66.35 kg和43.71 kg,分别提高32.75%、35.11%、57.37%和38.0%.18月龄公母牛平均体重分别比同龄蒙古牛增加78.75 kg、96.73 kg、107.72 kg和100.59 kg,分别提高35.84%、44.02%、49.03%和45.78%.30月龄公母牛平均体重分别比同龄蒙古牛增加67.07 kg、84.86 kg、110.18 kg和116.26 kg,分别提高19.86%、25.13%、32.62%和34.42%.     

Impact of management interventions on helminth levels,and body and blood measurements in working donkeys in South Africa

The aim of the study was to determine the effect of alternative management interventions on levels of nematodes and the condition of working donkeys in South Africa. Twenty-four adult donkeys (Equus asinus) within an area of 200km radius were randomly allocated to eight paddocks. Two replicates each of three management interventions together with a control group were tested in a 16-month study. The interventions included monthly removal of feces from paddocks where the donkeys grazed, a pre-winter moxidectin treatment, and a combination of a pre-winter moxidectin treatment and monthly fecal removal. The influence of the different interventions on the nematode fecal egg counts, animal live weights, body condition scores and general blood chemistry were compared. In addition, herbage samples were collected from the pastures in each paddock to determine the number of third-stage larvae (L(3)) per kg dry matter. At the end of the study worm recoveries and counts were performed on eight of the animals following euthanasia. The cyathostomes represented the largest portion of the helminth species composition in both the fecal egg counts and larval cultures. Monthly fecal removal alone did not significantly reduce the L(3) on pasture and consideration of more frequent removal is discussed. Pre-winter moxidectin treatment resulted in a 100% reduction in fecal egg counts, an average egg reappearance period of 42-55 days, a reduced average egg count for up to 8 months, and reduced total helminth burdens in all the treated donkeys. It also resulted in improved live weights, hemoglobin concentration, packed cell volumes and to some extent body condition score of the donkeys.     

红豆杉干粉对产蛋初期仙居鸡生产性能和生化指标的影响

本试验旨在研究饲粮中添加不同水平的红豆杉干粉对产蛋初期仙居鸡的生产性能、血清脂质代谢和抗氧化指标的影响。选取400只140日龄仙居鸡,随机分成4组,每组5个重复,每个重复20只。对照组饲喂基础饲粮,试验组在基础日粮中分别添加2%、3%和4%红豆杉干粉,预试期7 d,正试期90 d。结果表明:在试验初期(1～30 d),各试验组平均日采食量(ADFI)均低于对照组(P<0.05),4%红豆杉干粉组的产蛋率低于对照组(P<0.05);在试验中期(31～60 d),各试验组ADFI、平均蛋重与对照组无显著差异, 4%红豆杉干粉组的产蛋率高于对照组(P<0.05),4%红豆杉干粉组的料蛋比低于对照组(P<0.05);在试验后期(61～90 d),3%红豆杉干粉组的平均日采食量高于对照组(P<0.05),3%红豆杉干粉组的平均蛋重低于对照组(P<0.05),4%红豆杉干粉组的产蛋率高于对照组(P<0.05);在试验46～90 d, 2%红豆杉干粉组平均日增重较对照组降低(P<0.05);各试验组血清总抗氧化能力高于对照组(P<0.05)。综上所述,饲粮中添加不同水平红豆杉干粉可以改善仙居鸡生产性能、血清生化指标和抗氧化能力,建议产蛋期日粮中添加4%红豆杉干粉。