Matus-Aragón Miguel Ángel, González-Cerón Fernando, Salinas-Ruiz Josafhat, Sosa-Montes Eliseo, Pro-Martínez Arturo, Hernández-Mendo Omar, Cuca-García Juan Manuel, Chan-Díaz David Jesús
Program of Animal Science, College of Postgraduates, Campus Montecillo, Texcoco, State of Mexico 56230, Mexico.
Department of Animal Science, Chapingo Autonomous University, Chapingo, State of Mexico 56230, Mexico.
Anim Biosci. 2021 Nov;34(11):1794-1801. doi: 10.5713/ab.20.0682. Epub 2020 Dec 11.
The study aimed to evaluate the productive performance, carcass yield, size of digestive organs and nutrient utilization in Mexican Creole chickens, using four diets with different concentrations of metabolizable energy (ME, kcal/kg) and crude protein (CP, %).
Two hundred thirty-six chickens, coming from eight incubation batches, were randomly distributed to four experimental diets with the following ME/CP ratios: 3,000/20, 2,850/19, 2,700/18 and 2,550/17. Each diet was evaluated with 59 birds from hatching to 12 weeks of age. The variables feed intake (FI), body weight gain (BWG), feed conversion (FC), mortality, carcass yield, size of digestive organs, retention of nutrients, retention efficiency of gross energy (GE) and CP, and excretion of N were recorded. Data were analyzed as a randomized block design with repeated measures using the GLIMMIX procedure of SAS, with covariance AR (1) and adjustment of degrees of freedom (KendwardRoger), the adjusted means were compared with the least significant difference method at a significance level of 5%.
The productive performance variables BWG, mortality, carcass yield, fat and GE retention and excretion of N were not different (p>0.05) due to the diet effect. In the 3,000/20 diet, the chickens had lower values of FI, FC, crop weight, gizzard weight, retention, and retention efficiency of CP (p<0.05) than the chickens of the 2,550/17 diet.
The Mexican Creole chickens from hatching to 12 weeks of age can be feed with a diet with 2,550 kcal ME and 17% CP, without compromising productive parameters (BWG, mortality, carcass yield) but improving retention and retention efficiency of CP.
本研究旨在通过使用四种不同代谢能（ME，千卡/千克）和粗蛋白（CP，%）浓度的日粮，评估墨西哥克里奥尔鸡的生产性能、胴体产量、消化器官大小和养分利用率。
来自八个孵化批次的236只鸡被随机分配到四种实验日粮中，其ME/CP比例如下：3000/20、2850/19、2700/18和2550/17。每种日粮用59只鸡从孵化到12周龄进行评估。记录了采食量（FI）、体重增加（BWG）、饲料转化率（FC）、死亡率、胴体产量、消化器官大小、养分保留、总能（GE）和CP的保留效率以及氮排泄等变量。数据采用SAS的GLIMMIX程序按随机区组设计进行重复测量分析，协方差为AR（1）并调整自由度（肯沃德-罗杰），在5%的显著水平下用最小显著差法比较调整后的均值。
由于日粮效应，生产性能变量BWG、死亡率、胴体产量、脂肪和GE保留以及氮排泄没有差异（p>0.05）。在3000/20日粮组中，鸡的FI、FC、嗉囊重量、肌胃重量、CP保留量和保留效率值低于2550/17日粮组的鸡（p<0.05）。
从孵化到12周龄的墨西哥克里奥尔鸡可以饲喂含2550千卡ME和17%CP的日粮，而不会影响生产参数（BWG、死亡率、胴体产量），但会提高CP的保留量和保留效率。
