817优质肉鸡生长规律的研究

选择健康817肉鸡商品雏200只为试验材料,饲养期共8周,在初生和各周龄末空腹称重,计算各周绝对增重、相对增重及饲料利用率。从研究结果看,817肉鸡体重的增长规律与快大型肉鸡的生长规律基本相同,绝对增重在6周龄最高,饲料利用率随周龄增长而逐渐降低。从试验结果看,817肉鸡以6-8周龄出栏经济效益最好。     

不同补饲水平对草地放养河北柴鸡生长曲线拟合的影响研究

了解不同补饲水平下河北柴鸡的生长发育规律。运用Gompertz非线性模型对不同补饲水平放养河北柴鸡0～20周龄体重生长资料进行曲线拟合和分析。在自由采食条件下,河北柴鸡的生长极限生长量、拐点体重及最大日增重最大;限饲条件下,拐点周龄延长至10.1周,极限生长量、瞬时生长速度、拐点体重及最大日增重明显降低;前期自由采食,后期停止补饲鸡的体重呈现直线下降,极限生长量和拐点体重最低。运用Gompertz模型适宜拟合不同补饲水平河北柴鸡的生长曲线(R2>0.99),为制订河北柴鸡不同生长阶段的营养及补饲标准提供参考。     

笼养麻黄母肉鸡的生长发育规律的试验研究

通过研究笼养麻黄母肉鸡的生长规律,为阶段配方营养标准的设计提供指导,随机选取1日龄麻黄母肉鸡10 000只,随机分成四个重复组,每组2 500只,记录各周龄末体重,计算各周的绝对增重、相对增重及小鸡、中鸡和大鸡阶段的料重比。结果表明,麻黄母肉鸡与快大型肉鸡不同,8周龄绝对增重最高,日增重可以达到44.1 g,相对增重率和饲料转化率都随着周龄的增加而逐渐降低。     

817肉鸡生长规律的探析

随机选取1日龄817杂交肉鸡360只,公母各半,常规饲养56d,记录各周龄末体重、采食量,计算各周绝对增重、相对增重及料肉比,并分析最佳出栏时间。结果表明,817肉鸡生长规律与快大型肉鸡较相似,7周龄绝对增重最高,日增重达45g以上,相对增重和饲料转化率都随周龄增加而逐渐降低。根据经济效益分析,817肉鸡以7～8周龄出栏为宜。     

棉粕日粮对艾维茵肉仔鸡的影响

采用“玉米—豆粕—棉粕”型日粮饲喂艾维茵肉仔鸡，测各周龄体重。并建立其回归方程、进行显著性检验。分析周增重与日增重、周增重与饲养成本间的多元回归关系与相关性。肉仔鸡饲养到第５周龄时，日增重最高为６０．９７ｇ，饲养到第６～７周龄时饲养成本最低为８．６６３元     

不同饲养方式下马岗鹅生长曲线分析

马岗鹅是广东五大地方良种鹅之一,本试验选用健康1日龄的马岗鹅100只,随机分成放牧组及舍饲组,每组50只。试验期为10周,于每周第1天早晨空腹称重,计算其各周的平均体重、各周的绝对增重、相对增重及每周日增重。利用Logistic曲线方程,对不同饲养方式马岗鹅10周龄的体重变化进行拟合。结果,不同饲养方式下马岗鹅体重增长趋势符合Logistic生长曲线,拟合优度R2均在0 99以上。舍饲条件下,马岗鹅的体重极限值K及生长速度参数b均高于放牧组。     

凤梨酵素复合酶和溶菌酶对华北柴鸡生产性能的试验

为探讨凤梨酵素复合酶和溶菌酶在地方鸡日粮中的使用效果.试验选用1日龄450只华北柴鸡,平均分成3个处理,每处理设3个重复,每重复50只鸡.日粮中分别添加凤梨酵素复合酶和溶菌酶,与盐霉素组进行对照,笼养,观测0～6周龄鸡生产性能和营养物质代谢率的影响.结果表明,添加凤梨酵素复合酶和溶菌酶显著提高华北柴鸡日粮中粗脂肪的消化率,显著改善饲料转化率,凤梨酵素复合酶显著改善华北柴鸡成活率.结果表明,凤梨酵素复合酶和溶菌酶具有提高华北柴鸡生产性能的效果.     

日龄和饲养方式对“华北柴鸡”鸡蛋品质的影响

在北京农效禽业有限公司随机选取健康状况良好、体重相近的19周和29周"华北柴鸡"各32只,编号Ⅰ、Ⅱ组,按每笼4只常规养殖密度饲养;在北京昌平微生态健康散养蛋鸡示范基地随机选取健康状况良好、体重相近的29周"华北柴鸡"32只散养,编号Ⅲ组。在相同环境条件下饲养,1周后在试验各组随机选取24 h产出蛋10枚,短时间内完成蛋重、蛋壳重、蛋壳厚度、蛋黄指数、蛋形指数和哈氏单位指标的测定与计算。试验结果表明,Ⅰ、Ⅱ、Ⅲ组蛋形指数无显著差异;笼养条件下"华北柴鸡"随着产蛋日龄的增加,蛋重增加、其他指标呈下降趋势;30周散养鸡蛋的蛋重接近20周笼养鸡蛋,蛋壳显著增厚。     

大午粉1号纯系蛋鸡体增重与产蛋数的关系

本试验旨在研究大午粉1号配套系中A、C、D纯系蛋鸡体重及体增重与产蛋数的关系。试验分析开产体重、18周龄体重、43周龄体重、18周龄至43周龄体增重(以下简称体增重)与开产至43周龄累计产蛋数(以下简称43周产蛋数)之间的相关性以及各纯系体增重不同范围与43周产蛋数的关系。结果表明:3个纯系的体增重均与18周龄体重、43周产蛋数呈负相关,而与43周龄体重呈极显著正相关(P0.01);3个纯系的43周产蛋数均与18周龄体重呈正相关,与43周龄体重呈负相关;A系蛋鸡的体重和体增重明显小于C系蛋鸡和D系蛋鸡的体重和体增重,但各纯系蛋鸡的体增重变异系数之间的差异比较小;A系体增重集中在100~500 g,其中体增重范围在100~400 g时的43周产蛋数显著高于其他体增重范围内的产蛋数(P0.05);C系和D系体增重集中在200~700 g,其中体增重范围在200~400 g时的43周产蛋数显著高于其他体增重范围内的产蛋数(P0.05)。     

饲粮粗蛋白质与赖氨酸水平对北京油鸡育雏期生长性能和血清生化指标的影响

本试验旨在研究饲粮粗蛋白质与赖氨酸水平对北京油鸡（简称油鸡）育雏期生长性能和血清生化指标的影响。选择1日龄油鸡混合雏1 350只，随机分为9组，每组5个重复，每个重复30只鸡（公母各占1/2）。采用3×3因子试验设计，饲粮粗蛋白质水平分别为17%、18%、19%，赖氨酸水平分别为0.85%、1.00%、1.15%，分别统计0～3周龄、4～6周龄和0～6周龄生长性能，6周龄末测定血清生化指标。结果显示：1）饲粮粗蛋白质水平对4～6周龄油鸡周平均采食量及周平均体增重有显著影响（P<0.05），粗蛋白质水平为19%时周平均采食量（251.85 g）与周平均体增重（85.52 g）最大；饲粮赖氨酸水平对4～6周龄油鸡料重比有显著影响（P<0.05），赖氨酸水平为1.00%时料重比最低（2.95）。0～6周龄饲粮粗蛋白质水平对油鸡周平均采食量有影响显著（P<0.05），随着粗蛋白质水平增加周平均采食量逐渐增加，且在粗蛋白质水平为19%时达到最大值（184.58 g）；赖氨酸水平对周平均体增重与料重比有显著影响（P<0.05）,1.00%和1.15%赖氨酸组的周平均体增重均...     

GROWTH RATE OF OSTRICH (STRUTHIO CAMELUS) CHICKS UNDER INTENSIVE MANAGEMENT IN BOTSWANA

Thirty-seven ostrich chicks raised artificially had their weights, lengths of metatarsus and heights measured weekly from hatching to the 16th week. Despite weight loss during the first week due to utilization of egg yolk by the chicks, the chicks showed an exponential growth up to the twelfth week with an overall mean weekly weight gain of 1.3 kg. Female chicks showed a superior mean weekly gain of 1.6 kg compared to 1.2 kg for males. The metatarsal length grew rapidly at a weekly rate of 2.5 cm, but began to decline in the 11th week even though the weights and heights of the chicks were still increasing. The correlation coefficient between body weight and metatarsal length was 0.97. Individual chicks also maintained their respective heavy or light weight hierarchies throughout the study period. Thus isolation of chicks into groups by weight and raising them separately could have a role in the artificial rearing of ostrich chicks. Furthermore, ostrich chick rearing may be improved by regularly weighing chicks as a means of detecting changes in the growth patterns.     

日粮蛋白质水平对育成阶段乌骨鸡生长性能的影响

为了研究日粮蛋白质水平对肉用乌骨鸡生产性能的影响,试验选用15周龄、体重接近的健康乌骨鸡288只,随机分成3个试验组,每个组设3个重复。3组饲喂粗蛋白质含量分别为17.85%、20.46%、22.45%的3种日粮。试验期为4周。试验结果显示:在16~20周龄,试验Ⅱ组的鸡日增重最高,为18.87 g/d。其日增重与试验Ⅰ、Ⅲ相比较,分别提高了13.89%、8.35%,差异显著(P0.05)。     

L-NMMA对鸡球虫早熟弱毒疫苗免疫鸡增重的影响

为了研究鸡球虫早熟弱毒疫苗对免疫鸡增重的影响及一氧化氮合成酶抑制剂(L-NMMA)对免疫鸡增重和免疫效果的影响。取40只SPF雏鸡,分为空白对照组(C1、C2)和单剂量重复接种组(T1、T2),T1、T2组按推荐免疫剂量单剂量重复接种鸡球虫早熟弱毒疫苗,C1和T1、C2和T2分别于二次接种后第7、14天逐只空腹称重,剖检记录十二指肠、空肠和盲肠病变记分,取心脏、肝脏、脾脏、肺脏、肾脏、腺胃、肌胃、十二指肠、空肠和盲肠进行病理组织学检查。另选取40只SPF雏鸡,分为空白对照组C20、攻毒对照组T21、免疫对照组T22和免疫加药组T23,T22和T23按推荐免疫剂量两次免疫鸡球虫早熟弱毒疫苗,T23在免疫的同时腹腔注射L-NMMA,二免后第14天T21、T22和T23均接种鸡球虫混合强毒,测定SPF雏鸡平均增重、相对增重、肠道(十二指肠、空肠和盲肠)病变记分、病变记分减少率(RLS)、血便记分、死亡率及卵囊产量等指标。结果显示,接种组的平均增重显著低于未接种组(P<0.05),接种组的十二指肠、空肠和盲肠有轻微病变且黏膜上皮细胞均有不同程度损伤和脱落;免疫加L-NMMA组一免、二免后及攻毒后试验鸡的平均增重均极显著高于免疫攻毒对照组(P<0.01),且与空白对照组鸡的平均增重无显著差异(P>0.05),且免疫对照组和免疫加药组肠道病变记分和卵囊产量无显著差异(P>0.05)。说明鸡球虫早熟弱毒疫苗对雏鸡肠道有轻微损伤,且对鸡增重有一定影响;L-NMMA可降低鸡球虫早熟弱毒疫苗对试验鸡增重的影响,且不影响疫苗的免疫效果。     

卵黄免疫球蛋白对雏鸡生长性能和免疫机能的影响

本试验旨在研究饲粮中添加卵黄免疫球蛋白(IgY)对雏鸡生长性能和免疫机能的影响。选取同一批出雏、体重相近的1日龄罗曼褐蛋鸡公雏240只,随机分为2组(对照组和试验组),每组6个重复,每个重复20只鸡。对照组饲喂基础饲粮,试验组在对照组饲粮基础上添加0.1%的IgY。试验期5周。分别于1、3、5周龄,每个重复选取接近该重复平均体重的试验鸡2只,称重、采血并用于血清免疫指标测定,然后取免疫器官、空肠食糜用于相关指标测定。结果表明:1)与对照组相比,试验组1、3、5周龄雏鸡平均日增重有增大的趋势(0.05P0.10)。2)试验组1、5周龄雏鸡胸腺相对重和1周龄脾脏相对重显著高于对照组(P0.05),试验组1、5周龄雏鸡法氏囊、脾脏、胸腺中IgY含量与对照组差异均不显著(P0.05)。3)试验组1周龄雏鸡血清球蛋白、α-干扰素、白细胞介素-2含量和溶菌酶活性,3周龄雏鸡血清总蛋白、球蛋白和白细胞介素-2含量,5周龄雏鸡血液淋巴细胞数量均显著高于对照组(P0.05)。4)试验组1周龄雏鸡肠道食糜中分泌型免疫球蛋白A含量显著高于对照组(P0.05)。由此可知,雏鸡饲粮中添加IgY可以促进雏鸡1~5周龄生长性能和免疫机能的提高,但从提高免疫机能的角度看,育雏前期(1~3周龄)的作用效果更为明显。     

黄芩多糖对肉仔鸡营养物质消化率、生长性能的影响

用黄芩多糖作为饲料添加剂,研究其对内用仔鸡主要营养物质代谢率以及生长性能的影响。试验选用体重相近的AA肉仔鸡120只,随机分成4个处理,每个处理3个重复,每个重复10只。各组基础日粮相同,试验组分别在基础日粮中按100、200和400 mg/kg饲粮添加黄芩多糖;并分别在第3周龄和第5周龄各进行4 d代谢试验,在7、14、21、35和49日龄以组为单位称重、称余料,计算耗料量、日增重和料重比。分别于21、35和49日龄每组随机取3只体重接近平均体重的鸡进行屠宰,采血,制备血清,进行相关指标检测。试验结果表明,在试验添加量范围内,黄芩多糖对内仔鸡养分代谢率具有降低作用,且对0-3周龄肉仔鸡的影响要大于3-7周龄。在3-7周龄,粗蛋白代谢率最高的是200 mg/kg黄芩多糖添加组,比对照组高24.04%,差异显著(P0.05)。200 mg/kg黄芩多糖添加组对内仔鸡体重、日增重和料肉比影响较显著。     

Effect of clinoptilolite on performance of Japanese quail (Coturnix coturnix japonica) during experimental aflatoxicosis

Clinoptilolite (CLI, a natural zeolite), incorporated into the diet at 50 g/kg, was evaluated for its ability to reduce the deleterious effects of 2.0 mg total aflatoxin (AF;83.06% AFB1, 12.98% AFB2, 2.84% AFG1 and 1.12% AFG2)/kg diet on growing Japanese quail chicks from 10 to 45 d of age. A total of 40 Japanese quail chicks were divided into 4 treatment groups (control, AF, CLI, AF plus CLI) each consisting of 10 chicks. The performance of the birds was evaluated. The AF treatment significantly decreased food consumption and body weight gain from the 3rd week onwards. The adverse effect of AF on food conversion ratio was also significant from week 4 of the experiment. The addition of CLI to an AF-containing diet significantly reduced the deleterious effects of AF on food consumption, body weight gain and food conversion ratio. Food consumption was reduced by 14% in quail chicks consuming the AF diet without CLI, but by only 6% for quail chicks consuming the AF plus CLI diet. Similarly, overall body weight gain was reduced by 27% in birds consuming the AF diet without CLI, but by only 8% for birds consuming the AF plus CLI diet. The addition of CLI to the AF-free diet significantly decreased food consumption and body weight gain during week 4, but these parameters were similar to the controls in week 5. No mortality was observed in any of the groups. These results suggest that CLI effectively diminished the detrimental effects of AF on the variables investigated in this study.     

肉鸡育雏期管理

肉鸡出栏体重与1周末体重呈正相关,出栏体重又与养殖效益有直接关系,而决定一周末体重的主要因素是入舍后的早期管理,尤其前3 d的管理对于肉鸡一生都至关重要。在肉鸡早期管理中需要重点关注环境条件的温度、湿度和空气质量,然后加强水线和采食管理,促使雏鸡尽快采食和饮水,为1周末达到理想的体重奠定基础。同时做好预防疾病工作,提高雏鸡体质和抗病能力,降低雏鸡死亡率,进而达到提高肉鸡养殖效益的目的。     

Effect of cysteamine administration on growth and efficiency of food utilisation in chicks

1. Cysteamine hydrochloride, which is a potent inhibitor of somatostatin secretion, was fed to male broiler chicks at dietary inclusion rates of 0, 25, 125, 250, 600, 1200, 1800 and 2400 mg/kg during three separate experiments. 2. Weight gain, food intake and efficiency of food utilisation were measured weekly over a two (experiment 1 and 2) or three-week period (experiment 3) during which chicks were 3 to 10 d old (week 1) to 17 to 24 d old (week 3). 3. Cysteamine hydrochloride included in the food at 1200 and 1800 mg/kg resulted in a significant increase in efficiency of food utilisation, attributable to a significant decrease in food intake. 4. There was no difference in weight gains between chicks in the control group and those receiving 1200 mg/kg. However a significant decrease in weight gain was observed in chicks receiving 1800 mg/kg.     

Relative virulences of a drug-resistant and a drug-sensitive strain of Eimeria acervulina, a coccidium of chickens

The virulence of a field strain of the chicken coccidian parasite Eimeria acervulina (Boreham I), dually resistant to the chemically unrelated anticoccidial agents decoquinate and clopidol, was compared with that of a drug-sensitive laboratory strain (Ongar) of the same species. Following a single heavy infection (prevented from recycling), both strains exhibited pathogenic effects typical of their species, viz., pathognomonic lesions, adverse effects on body weight gain and feed conversion ratio (FCR), but no mortality. One week after infection, chicks infected with either strain had a statistically significantly worse weight gain than the uninfected control; the Boreham I strain produced more oocysts, and caused slightly more severe duodenal lesions and poorer FCRs than the Ongar strain (all those effects being non-significant). After 3 weeks, there were no significant differences between any cumulative effects of either strain, nor any differences from the uninfected control. However, from 2 to 3 weeks after infection, chicks infected with either strain had a greater feed consumption and growth rate than uninfected chicks. When chicks reared on solid floors were given lighter infections of either strain, which were allowed subsequently to recycle naturally, there were no consistent reductions in weight gains, but feed consumption was higher than that of uninfected chicks. Whatever, the mode of infection, there were no significant differences between the weights of infected and uninfected chicks after 3 weeks, but the FCR of infected chicks was usually poorer than that of uninfected chicks. The difference between the virulences of the Boreham I and Ongar strains was not greater than that between various drug-resistant strains or between various sensitive strains of several Eimeria species recorded in the literature. It is therefore concluded that there was no difference between the virulences of the two strains of E. acervulina that could be attributed to the drug-resistance of one of them.