摘要
【目的】研究中国新培育的京红蛋鸡(0—4周龄)饲粮蛋氨酸需要量。【方法】选取300只体重相近、健康的1日龄京红蛋鸡,采用单因素完全随机试验设计,随机分5个处理,饲粮蛋氨酸水平分别为0.2%、0.3%、0.4%、0.5%和0.6%,每处理5个重复,每重复12只鸡。试期28 d。在14 d随机从每个重复选2只鸡空腹12 h屠宰,取胸腺、脾脏和法氏囊,计算免疫指数;在28 d随机从每个重复选2只鸡空腹12 h屠宰,分别取免疫和消化器官,计算相应指数。【结果】(1)饲粮蛋氨酸水平未见显著影响雏鸡采食量(P>0.05),但显著影响其增重(P<0.05),其中0.4%Met组鸡增重最大,且该组雏鸡ADG为8.31 g·d-1,显著高于0.2%、0.5%和0.6%Met组(P<0.05),且呈二次曲线升高趋势;显著影响料重比(P<0.05),其中0.5%Met组最佳(2.13﹕1),显著低于0.2%和0.3%Met组(P<0.05),呈二次曲线趋势降低;显著影响体重,且呈现二次曲线升高,0.4%Met组体重为268.70g,显著高于0.2%、0.5%和0.6%Met组(P<0.05);群体均匀度也呈现二次曲线升高,0.5%Met组最佳(85.19%),显著高于其它处理组(P>0.05)。(2)14 d,饲粮蛋氨酸水平未显著影响雏鸡胸腺指数和法氏囊指数(P>0.05),显著影响脾脏指数(P<0.05),0.4%Met组最大;28 d,鸡胸腺、脾脏和法氏囊指数均随饲粮Met水平呈显著正相关关系(P<0.05),且呈先升后降的趋势。其中,0.4%Met组脾脏和法氏囊指数最大,0.5%Met组胸腺指数最大。(3)饲粮Met水平未显著影响胰腺指数和十二指肠相对长度(P>0.05),显著影响蛋鸡十二指肠、空肠和回肠重量指数和空肠回肠长度指数(P<0.05)。随饲粮蛋氨酸水平升高,胰腺指数呈先升后降趋势,十二指肠、空肠和回肠重量指数和空肠、回肠长度指数均呈先降后升趋势。0.3%Met组十二指肠指数显著低于0.2%、0.5%和0.6%Met组(P<0.05);0.4%Met组的空肠指数显著低于其他Met组(P<0.05),0.5%Met组的空肠相对长度显著低于0.2%、0.3%和0.6%Met组(P<0.05);0.4%Met组的回肠指数显著低于0.6%Met组(P<0.05),0.3%Met组的回肠相对长度显著低于0.2%、0.5%和0.6%Met组(P<0.05)。(4)饲粮Met水平显著影响鸡血清尿素氮、尿酸和碱性磷酸酶水平(P<0.05),其中0.6%Met组的雏鸡血清的血清尿素氮显著高于0.2%、0.4%和0.5%Met组(P<0.05),且0.5%Met组血清尿素氮最低、碱性磷酸酶水平最高(P<0.05);0.6%Met组尿酸显著高于其他组(P<0.05);但饲粮Met水平未见显著影响鸡血清白蛋白、总蛋白(P>0.05)。5)通过对鸡体重和料重比二次曲线拟合得出饲粮Met最佳剂量为0.466%和0.507%,平均0.487%。【结论】综合鸡群增重、料重比、群体均匀度等经济指标、免疫指标、消化系统发育和血液生化指标,推荐0—4周龄京红蛋鸡饲粮蛋氨酸需要量为0.49%。
【Objective】Dietary methionine（Met） levels for China＇s new cultivation of Jinghong laying hens from hatch to the age of 4 weeks were studied.【Method】The trial had adopted one-factor completely random design. Three hundred 1-day-old Jinghong laying hens from a commercial supplier in YuKou poultry were randomly allotted to 5 dietary treatment groups, and the birds in the treatment groups were fed a diet with different dietary methionine levels, respectively, i.e. 0.2%（0.2% Met）, 0.3%（0.3% Met）, 0.4%（0.4% Met）, 0.5%（0.5% Met） and 0.6%（0.6% Met）. Each treatment group consisted of 5 replicates with 5 pens per replicate and 12 birds per pen. The experiment lasted for 28 days. On 14th day, after being deprived of feed for 12 h, 2 birds selected randomly from each pen were slaughtered by neck cut and birds were eviscerated manually. The thymus, spleen and bursa of fabricius were weighed and were expressed as a percentage relative to live BW at processing. On 28th day, after being deprived of feed for 12 h, 2 birds selected randomly from each pen were slaughtered by neck cut and birds were eviscerated manually. The immune organs and digestive organs were weighed and were expressed as a percentage relative to live BW at processing.【Result】No significant differences were found in average daily feed intake（P0.05）, but the average daily gain was significantly different（P0.05）, and the birds in 0.4% Met group showed the maximum value with 8.31 g·d-1 and significantly higher than 0.2%, 0.5% and 0.6% Met groups（P0.05）, with a quadratic curve of a rising trend. Besides, feed/gain ratios were also significantly affected（P0.05）, and the 0.5% Met group was the best（2.13：1） and significantly lower than 0.2% and 0.3% Met groups（P0.05）, with a quadratic curve of reducing trend. Body weight was significantly affected（P0.05）, and the 0.4% Met group was the best（268.70 g） and significantly higher than 0.2%, 0.5% and 0.6% Met groups（P0.05）, with a quadratic curve of rising trend. Community evenness also showed a tendency of a quadratic curve of rising, the 0.5%Met group（85.19%） was significantly higher than the other groups（P0.05）. By the end of 2nd week, no-significant influence on the relative weights of the thymus and bursa of fabricius（P0.05） was found among different groups. There was a significant impact on the relative weights of the spleen（P0.05）, the 0.4% Met group reached the maximum. By the end of the 4th week, the relative weights of the thymus, spleen and bursa of fabricius showed a significant positive correlation（P0.05） with dietary Met levels and all values had a rise-fall tendency. The relative weights of the spleen and bursa of fabricius in 0.4% Met group were the largest; the thymus index in 0.5% Met group was the largest. No significant differences were found in pancreas index and the relative lengths of the duodenum（P0.05）, but the relative weights of the duodenum, jejunum and ileumor or the relative lengths of the jejunum and ileum were significantly different（P0.05）. With the increase of methionine, except the relative weights of pancreas which showed a rise-fall tendency, the relative weights of the duodenum, jejunum and ileumor or the relative lengths of the jejunum and ileum had shown a fall-rise tendency. The relative weights of the duodenum in 0.3% Met group were significantly lower than 0.2%, 0.5% and 0.6% Met groups（P0.05）. The relative weights of the jejunum in 0.4% Met group were significantly lower than other Met groups（P0.05）. The relative lengths of the jejunum in 0.5% Met group were significantly lower than 0.2%, 0.3% and 0.6% Met groups（P0.05）. The relative weights of the ileumor in 0.4% Met group were significantly lower than 0.6% Met group（P0.05）. The relative lengths of the ileumor in 0.3% Met group were significantly lower than 0.2%, 0.5% and 0.6% Met groups（P0.05）. There were significant differences among groups in the level of serum urea nitrogen, uric acid and alkaline phosphatase（P0.05）. The level of serum urea nitrogen in 0.6% Met group was significantly higher than 0.2%, 0.4% and 0.5% Met groups（P0.05）. The 0.5% Met group was the minimum of serum urea nitrogen, while alkaline phosphatase was significantly higher than the other groups（P0.05）. Uric acid in 0.6% Met group was significantly higher than the other groups（P0.05）, but no significant differences were found in albumin, total protein by different methionine levels（P0.05）. According to quadratic curve estimation of the weight and feed/gain ratio, the optimal methionine levels were 0.466% and 0.507%, which could be averaged to 0.487%.【Conclusion】Combined with the average daily gain, feed/gain ratio, community evenness and other economic indicators, immune index, digestive system, index of blood, the optimal methionine requirement of Jinghong laying hens of 0-4 weeks is 0.49%.
出处
《中国农业科学》
CAS
CSCD
北大核心
2014年第12期2446-2454,共9页
Scientia Agricultura Sinica
基金
国家科技支撑计划(2011BAD26B03)
现代农业产业技术体系(CARS-41-K13)
现代农业产业技术体系北京市家禽创新团队(CARS-PSTP)
关键词
饲粮
蛋氨酸
京红蛋鸡
生长发育
器官发育
feed
dietary methionine
Jinghong laying hens
growth development
organ development
