绿壳蛋土鸡若干种质特性的研究

实验对绿壳蛋土鸡生长发育等有关特性进行观测，结果表明：公鸡的生长速度比母鸡快，到13周龄时公母鸡体重分别为1355g和1067g；公鸡的胫长、胫围、龙骨长、胸角测定值高于母鸡，而体斜长、胸围、胸宽、胸深公母鸡相差不大；上述各体尺与体重的相关系数分别为-0．623、0．278、0．868、-0．013、-0．081、0．585、0．608和0．108：13周龄公母鸡在屠宰性状方面存在差异，公鸡的腿肌率、胸肌率、翅膀率、全净膛率和半净膛率分别为26．2％、18.3％、13．8％、89．2％和70．9％，母鸡为19．4％、13．9％、11．0％、90．4％和72．5％，公鸡的腿肌率、胸肌率和翅膀率高于母鸡，而半净膛率和全净膛率却比母鸡低。     

日粮能量蛋白水平对肉用型种公鸡繁殖性能的影响

１材料和方法１．１试验时间和地点本试验于２０００年５月初开始，同年７月中旬结束，地点为辽宁某父母代肉种鸡场。１．２试验动物和饲养管理３９～５０周龄的艾维茵肉用父母代种公鸡为试材，种公、母鸡同舍笼养，人工授精。试验期每天１６h光照，强度为１０勒克斯；依据舍内温度机械通风；种公鸡每天人工给料１２０g，限制饮水；人工拣蛋４次，每日喂料前人工清粪；定期喷雾消毒。１．３试验设计及饲料配方选择３９周龄健康种公鸡７２只，随机分为９组，每组８只，一鸡一笼；另选择健康同周龄种母鸡４３２只，也随机分为９组，每组４８只…     

贵妇鸡若干种质特性的研究

本试验对贵妇鸡早期生长发育等有关指标进行观测，以揭示该鸡种质特点及性状相关。并应用多元回归分析方法探讨体斜长、胸角、胸骨长、主翼羽长，尾羽长，胫长和胫围对体重的相关，结果表明，公鸡早期生长速率较母鸡快，平均日增重比母鸡高０．９３ｇ，公母鸡６周龄体重 ３７５．０３ｇ和３３６．７７ｇ；     

不同周龄麒麟鸡生长性能测定

为了测定麒麟鸡的生长性能，选用1日龄雏鸡204只，分为公母2个处理组，每个处理有6个重复，每个重复17只，进行为期16周龄的试验。结果表明：1日龄公母体重分别为34．74g和33．85g，两者间无显著差异（P〉0．05），16周龄体重分别为2465．01g和1791．36g，第2～16周公母间体重差异一直处于极显著水平（P〈0．01）。麒麟鸡母鸡的料重比均高于公鸡。公鸡的生长速率均高于母鸡，随着日龄的增加，相对生长速率均呈现逐渐下降趋势。     

信宜怀乡鸡生长和肉用性能测定结果

笔者选用信宜怀乡鸡商品雏120只,分为公、母2个处理组,每个处理组有4个重复,每个重复15只,进行了0周龄~16周龄的饲养试验,旨在探讨怀乡鸡的生长与肉用性能。结果表明,16周龄公、母鸡体重分别为1744 g和1590 g,差异显著(P0.05);16周龄屠宰性能,总体趋势是公鸡大于母鸡,差异显著(P0.05),而腹脂重、肌间脂肪宽和皮下脂肪厚为母鸡大于公鸡,差异显著(P0.05);16周龄肌肉品质,胸、腿肌的粗蛋白含量均是公鸡显著高于母鸡(P0.05),而粗脂肪含量均是母鸡高于公鸡,差异显著(P0.05)。     

仙居鸡早期肉用性状的测定与遗传力估计

通过测定仙居鸡体重、体尺、屠宰和肉品质性状,研究其肉用特性。试验用12个公鸡家系的720只健康雏鸡(公、母各半),进行为期12周的饲养。每周测定个体重,12周龄时每个家系取5只公鸡、5只母鸡测定其体尺、屠宰性能和肉品质。结果表明:2周龄后公鸡体重均极显著大于母鸡(P<0.01),12周龄公、母体重分别为858.9g和719.5g;12周龄公鸡的体斜长、龙骨长、胫长、胫围都显著大于母鸡(P<0.05);公鸡的屠体率、半净膛率、胸肌率、头率、爪率、心率、肝率等指标均极显著大于母鸡(P<0.01),而肌、腺胃率则是母鸡极显著大于公鸡(P<0.01);公鸡胸肌剪切力显著大于母鸡(P<0.05)。     

AA肉仔鸡潜在生长性能预测及其生长曲线拟合的研究

本文采用Gompertz模型对处于不同日粮代谢能水平下0～8周龄AA肉鸡的生长曲线进行分析和非线性曲线拟合研究。结果显示:1周龄前公鸡、母鸡均生长缓慢,1周龄后生长速率开始增加,5周龄左右达到增重高峰,对公鸡而言,7周龄后日粮中14.23、13.39MJ/kg和11.72MJ/kg代谢能组生长速率均较7周前变缓。母鸡与公鸡具有相似的生长趋势,但1～2周龄时母鸡比公鸡有较大的生长速率,表现在母鸡体重比公鸡体重较大(P0.05),3周龄后同一水平下母鸡的生长速率显著慢于公鸡生长速率(P0.05)。Gompertz方程能较好地拟合公鸡与母鸡的生长曲线,其中13.39MJ/kg代谢能组的极限体重最高,拟合度分别达到99.9%、99.6%,拟合效果最好。采用Gompertz模型对0～8周龄公鸡与母鸡生长曲线拟合的方程分别为:BWt=5262.19×e{-e[-0.044×(t-36.093)]}和BWt=4823.04×e{-e[-0.045×(t-34.960)]}。该模型可用于肉仔鸡潜在生长性能的预测。     

爱拔益加种公鸡的培育

一、公鸡育雏期的饲养管理1、公母鸡分群饲养由于公雏比母皱小,比母雏弱,公雏采食量少.所以需要与母雏分群饲养,给以精心照顾。公母雏如不能分群饲养,会导致公鸡早期发育受阻,性腺发育迟缓.所以,爱拔益加种鸡 ,要求在育雏期(0-4周)和育成斯(5-20周)分群饲养,然后在20周龄与母鸡合群饲养,公母鸡分群饲养,更有利于提高     

如何让肉鸡生长均匀

密度要恰当每群鸡以300～500只为宜。饲养密度：1～2周，18～25只/m^2；3～6周龄，公鸡5～6只／m^2,母鸡8～10只／m^2；3～6周龄，公鸡5～6只／m^2,母鸡8～10只／m^2；7～16周龄，7～8只/m^2；16周龄后，5只／m^2为宜。     

佳和黄父母代肉种鸡饲养管理要点

一、1-20周龄公母分群饲养 0-5周龄（育雏期）饲养管理：佳和黄肉种鸡公鸡叶5周龄的培育目标是：体格健壮，腿长、平胸，睾丸发育良好，体重比母鸡高30％左右，行走时龙骨与地面的角度约成45度。为使种公鸡有较长的腿部，种公鸡早期不能过渡限制饲喂。因为8周龄前腿部骨骼生长较快。种公鸡在0-5周龄饲喂雏鸡料，自由采食，     

Effects of egg weight on the egg quality,chick quality,and broiler performance at the later stages of production (week 60) in broiler breeders

The objective of the present study was to determine the effect of broiler breeder egg weight on egg quality, chick quality, and broiler performance using Hubbard Classic broiler breeder flock. Hatching eggs from a commercial broiler breeder flock (Hubbard classic strain) were obtained at the age of 60 wk and divided into 3 egg-weight categories, namely small, medium, and large. For this purpose, 930 eggs having weights 63.09 ± 0.21, 68.85 ± 0.23, and 74.81 ± 0.11g were divided into 3 egg categories labeled small, medium, and large respectively. We further divided these eggs into 2 categories, eggs for quality parameters and eggs for incubation and posthatch performance parameters. Eggs from the small egg category had greater proportion of the shell weight and more shell strength. Egg weight did not significantly affect the albumen and yolk weight percentage. Egg weight affected the shape index and specific gravity for which lower values were observed for large eggs. Egg weight positively affected the chick weight, chick yield, and chick length (P < 0.05) of both male and female chicks. Results of the body weight gain showed that effect of egg weight on the posthatch performance of chick diminishes with the age of broilers. Egg weight significantly affected the body weight gain of male and female chicks up to 3 wk of age. Egg weights did not significantly affect the feed intake and mortality of broiler. Different egg-weight categories significantly affected the feed conversion ratio of female chicks at wk 2 and 3 of age and did not affect the feed conversion of male and female chicks at the end of wk 5. In conclusion, egg weight positively affected the chick characteristics (e.g., chick weight, chick length) and did not affect the final live body weight, feed conversion ratio, feed intake, and mortality in broilers.     

几内亚热带气候对海波罗肉用仔鸡长期耗料量及料肉比影响的研究

分4批从孵出的海波罗鸡雏中选出888只公母混合雏，每批222只，研究几内亚热带气候对海波罗肉仔鸡生长期耗料量的影响。结果表明，4批鸡的整个试验中的累计耗料量分别为4745.58g/只、4507.44g/只、4682.73g/只和4545.77g/只。第Ⅱ、Ⅲ和Ⅳ批鸡的累计耗料量比第Ⅰ批鸡分别少5.28%、1.13%和4.40%，第Ⅱ和第Ⅳ批累计耗料量比第Ⅲ批分别少4.11%和3.23%，第Ⅱ批累计耗料量比第Ⅳ批的少0.5%，比第Ⅰ、Ⅲ和Ⅳ批偏少。4批鸡4周龄料肉比分别为1.23、2.03、1.90和1.67，饲料报酬都高，7周龄分别为3.78、2.97、2.56和2.52，除第Ⅰ批外，各批7周龄饲料报酬较高。在整个试验期，4批鸡1－7周龄的平均累计耗料量为4622.88g/只，其平均累计料肉比为2.28g，累计耗料量比海波罗的标准少217.12g，即4.70%。由于几内亚热带气候影响，本试验鸡采食量少，料肉比较低。     

不同性别肉鸡心肌易颤性、血清酶活性和电解质水平的比较

对不同性别肉鸡的心肌易颤性、血清酶活性和电解质水平进行了比较,结果表明:(1)雄性肉鸡的电刺激诱颤阈和输钾诱颤阈均显著低于雌性肉鸡(P<0.05),二者均表明雄性肉鸡的心肌易颤性高于雌性肉鸡;(2)冷加压试验:冷加压5 min内心率和PT波宽出现了显著的变化,而且变化幅度雄性肉鸡均明显大于雌性肉鸡,提示雄性肉鸡的心肌易颤性高于雌性肉鸡;(3)雄性肉鸡LDH活性和CK活性极显著高于雌性肉鸡(P<0.01),而AST活性无显著差异(P>0.05);(4)K 、Na 、Cl-浓度均无显著差异(P>0.05)。     

饲养密度和高蛋白质饲粮代谢能水平对公母分饲肉鸡生长性能和腿部健康的影响

本试验旨在研究饲养密度与高蛋白质(前期23%,后期21%)饲粮代谢能水平对公母分饲肉鸡生长性能和腿部健康的影响。试验采用2(性别)×2(饲养密度)×3(饲粮代谢能水平)三因子完全随机设计,选用1日龄罗斯308(Ross 308)肉鸡公雏1 872只和母雏2 160只,随机分成12个组,每组8个重复。试验设高、低2个饲养密度,以出栏体重计,分别为42[高饲养密度(HSD),16公/m2或18母/m2]和26 kg/m2[低饲养密度(LSD),10公/m2或12母/m2]。试验饲粮分前期(1~21日龄)和后期(22~35日龄)2个阶段配制,饲粮代谢能设高、中、低3个水平,其中,高代谢能(HME)水平饲粮前期和后期的代谢能水平分别为12.81和13.23 MJ/kg,中代谢能(MME)水平饲粮前期和后期的代谢能水平分别为12.18和12.60 MJ/kg,低代谢能(HME)水平饲粮前期和后期的代谢能水平分别为11.55和11.97 MJ/kg。结果表明:1)饲养密度与饲粮代谢能水平对肉鸡的平均日增重和料重比有显著交互作用(P0.05)。1~21日龄时,随着饲粮代谢能水平增加,HSD组平均日增重的增加幅度和料重比的降低幅度均小于LSD组;22~35日龄时结果正好相反。性别与饲养密度对肉鸡的平均日采食量有显著交互作用(P0.05)。随着饲养密度增加,公鸡平均日采食量的降低幅度大于母鸡。2)HSD极显著降低肉鸡的胸肌率(P0.01),母鸡的胸肌率和腹脂率显著高于公鸡(P0.05)。饲粮代谢能水平和饲养密度对肉鸡的腿肌率有显著交互作用(P0.05)。随着饲粮代谢能水平增加,LSD组肉鸡的腿肌率降低,而HSD组基本不变。3)高饲粮代谢能水平极显著降低肉鸡的脚垫损伤评分(P0.01),公鸡的步态评分和脚垫损伤评分显著高于母鸡(P0.05),垫料水分含量显著低于母鸡(P0.05)。饲粮代谢能水平与饲养密度对肉鸡的脚垫损伤评分有显著交互作用(P0.05)。随着饲粮代谢能水平增加,HSD组脚垫损伤评分的降低幅度大于LSD组。以上结果表明,高饲养密度降低肉鸡的平均日增重,增加料重比;35日龄前,公鸡比母鸡的空间需求更高;提高高蛋白质饲粮的代谢能水平可以缓解HSD对肉鸡生长性能和脚垫健康的不利影响。     

Energy metabolism of growing broiler chickens kept in groups in relation to the environmental temperature. 1. Feed intake, heat production and energy utilization]

In 5 experiments with young broiler chickens kept in groups at environmental temperatures (ET) of 35, 30, 25, 20 and 15 degrees C feed intake, live weight development and heat production were ascertained between their 5th and 57th days of life. Feed intake and live weight were ascertained separately according to sex. With live weight being the same, feed intake increased with decreasing ET. There was no maximum feed intake up to the 57th day of life at between 20 and 25 degrees C. At the end of their 57th day of life the male and the female chickens had achieved the following live weights (in the sequence of decreasing ET 35-15 degrees C): 1342; 2014; 2829; 2946; 2374 and 1367; 1900; 2512; 2496 and 2200 g/animal resp. The highest live weight gain of the chickens was achieved at between 25 and 20 degrees C with 60-70 g/d for male and with 50-60 g/d for female animals. Heat production (HP) increased progressively with age. The highest HP was registered at 20 degrees C ET.     

Limited effect of intense genetic selection for broiler traits on ovarian function and follicular sensitivity in broiler breeders at the onset of lay

Female chicks from 6 pure lines of broiler breeders were obtained from international broiler breeder companies. The lines were from three female and two male lines and a relaxed selection line derived from one of the male lines (M2) and maintained without selection for 25 years (generations). Replicate groups from each line were reared in floor pens and fed ad libitum. An additional group of the M2 male line was feed restricted and housed in similar pens. Twenty birds from each group were photostimulated after housing them in individual cages at 14 weeks of age. Ovarian follicular dynamics and follicular sensitivity were determined after the onset of lay. Female lines had a greater proportion of atretic follicles and more groups of multiple follicles than male lines. Body weights, fatness and age at puberty were similar in male and female lines. The relaxed selection line had more abdominal fat than any of the selected lines and the ovary contained a similar number of normal yellow follicles as the selected male line. Feed restriction decreased body weight, the numbers of yellow follicles, multiple yellow follicles and the proportion of atretic yellow follicles, and increased the age at onset of lay. The response of ovarian follicles of three different sizes to exogenous gonadotrophin stimulation with PMSG was similar in small yellow follicles, 5 to 6 and 2 to 3 mm white follicles in a female line, a male line and its relaxed line fed ad libitum. The results suggest that the original lines from which modern male-line broiler stocks are derived had a relatively large number of yellow follicles and a high propensity for multiple ovulation at the onset of lay. Separate selection for different traits in male and female lines has not had a dramatic effect on ovarian function or sensitivity to gonadotrophin stimulation.     

Effect of formic acid on performance, digestibility, intestinal histomorphology and plasma metabolite levels of broiler chickens

1. The effect of dietary formic acid on performance, digestibility, intestinal histomorphology and plasma metabolite levels of broiler chickens was studied. 2. An experiment with 120 Ross male broiler chickens was conducted from 1 to 42 d of age at the laboratory. There were 4 treatment groups: control (C), 10 mg/kg feed avilamycin (AV) and formic acid at two concentrations, 5 and 10 g/kg feed (FA5 and FA10, respectively). 3. No differences in weight gain, feed intake or feed conversion ratio were observed in male broiler chickens fed on the different diets. 4. An effect of the additives on ileal dry matter (DM) digestibility at 42 d of age was detected with the finisher diets; AV and 10 g/kg of feed formic acid slightly improved ileal DM digestibility compared to the other treatment groups. 5. Jejunum pH was not affected when 5 or 10 g/kg formic acid was added, and the results do not clearly show a positive effect of formic acid on the intestinal histomorphology. 6. No differences were noticed for blood metabolites in the different diets, and the levels of calcium and phosphorus in the plasma were not altered by formic acid addition. 7. In conclusion, when using broiler chickens under conditions of good hygiene, dietary formic acid did not have a clear positive effect on performance, intestinal histomorphology or plasma metabolite levels; however, there was a slight positive effect on the ileal digestibility of nutrients.     

雉鸡、吉林本地三黄鸡和肉鸡的肉品质分析研究

为了研究雉鸡、吉林本地三黄鸡和肉鸡之间的肉品质差异,每个品种各选取20只鸡,雌雄各半,在同等条件下进行饲养至出栏日龄。采用常规方法测定不同品种肉鸡的肉品质性状指标,以及肌肉蛋白含量和肌内脂肪含量,利用统计学方法对各品种肉鸡的相关测定指标进行比较分析。结果表明,雄性雉鸡的肌肉系水力最高,与肉鸡、吉林本地三黄鸡差异显著（P<0.05）;雌性雉鸡和肉鸡的肌肉系水力显著（P<0.05）高于吉林本地三黄鸡。雄性和雌性肉鸡的滴水损失率、水浴损失率均显著（P<0.05）高于相应性别的雉鸡和吉林本地三黄鸡。同性别的3个品种鸡的肌肉pH_{24 h}值未表现出品种差异（P>0.05）。同性别的3个品种鸡的肌纤维直径指标表现出显著的品种差异（P<0.05）。雄性雉鸡的肌纤维密度最大,与肉鸡、吉林本地三黄鸡差异显著（P<0.05）;3个品种雌性鸡的肌纤维密度存在显著的种间差异显著（P<0.05）。在肌肉剪切力指标上,雄性吉林本地三黄鸡剪切力最大,与雉鸡、肉鸡差异显著（P<0.05）;雌性雉鸡剪切力最小,三黄鸡剪切力最大,3个品种的雌性鸡剪切力表现出显著的品种差异（P<0.05）。雌性和雄性雉鸡、吉林本地三黄鸡的肌肉蛋白含量显著（P<0.05）高于相应性别的肉鸡。相同性别的3个品种鸡,其肌内脂肪含量之间差异均显著（P<0.05）。综上所述,3个品种鸡的肉品质指标以及肌肉蛋白含量和肌内脂肪含量存在差异,雉鸡、吉林本地三黄鸡肉品质优于肉鸡,可作为本地饲养的首选品种。     

Impact of dietary chitosan oligosaccharide and its effects on coccidia challenge in broiler chickens

ABSTRACT

1. Two experiments were conducted, the first to determine the optimum inclusion of chitosan oligosaccharide (COS) in broiler diets to support growth performance, digestive functions, intestinal morphology, and immune organs. The second experiment evaluated the immune-protective properties of COS on broiler chickens during coccidia challenge (CC).

2. Experiment 1 investigated the effect of graded dietary concentration of COS in the diets of broiler chickens using eight cage replicates for each of the six diets. A corn-soybean meal-based diet was used as the basal diet and supplemented with 0.0, 0.5, 1.0, 1.5, 2.0, or 2.5 g of COS/kg feed to form the six treatments.

3. The diet supplemented with 1.0 g COS/kg of feed provided the optimal inclusion level for broiler chickens regarding body weight (BW) gain, jejunal villus height, villus height to crypt depth ratio, and ileal energy digestibility at d 22 of age.

4. Experiment 2 investigated the immune-protective properties of COS in broiler chickens during CC. A total of 224 male broiler chicks were randomly assigned to eight replicate cages in a 2 × 2 factorial arrangement of treatments with two COS concentrations (0 or 1 g of COS/kg of diet), with or without CC.

5. On d 18 of age, birds in the CC group received twice the recommended coccidia vaccine dose of 30 doses/kg BW.

6. Coccidia challenge reduced (P < 0.05) and dietary COS increased (P < 0.05) BW gain, and feed intake. Dietary COS mitigated (P < 0.05) the CC-induced effects on gain:feed. Dietary COS supplementation attenuated the CC-induced effects (P < 0.05) on the expression of occludin genes.

7. In conclusion, dietary COS improved performance, and the immune-related beneficial impact of COS supplementation was associated with reduced expression of pro-inflammatory cytokine genes.