Ceron-Romero N, Taofeek N, Thomas A, Vroonland E, Sanmartin K, Verghese M, Heinen E, Vizcarra J A
Food and Animal Sciences, Alabama A&M University, Normal, AL 35762, USA.
Elanco Animal Health, Greenfield, IN 46140, USA.
Poult Sci. 2021 Aug;100(8):101204. doi: 10.1016/j.psj.2021.101204. Epub 2021 Apr 20.
Ghrelin is a hormone that induces orexigenic effects in mammals. However, in avian species, there is scant and conflictive results on the effect of ghrelin on feed intake (FI). Therefore, we evaluated the effect of a ghrelin receptor agonist (capromorelin) on FI, ADG, water intake (WI), animal behavior and concentrations of ghrelin, glucose, growth hormone (GH) and insulin in broiler chickens. One-day-old male broilers were reared as recommended by the industry. At 4 wk of age (experimental day 0; D0), birds were blocked by weight and randomly assigned to 3 treatments in 2 identical trials. Control birds received a vehicle control solution containing 0 mg/kgBW/d of capromorelin. Birds in treatments 2 and 3 received capromorelin at target doses of 6 or 12 mg/kgBW/d of capromorelin (n = 27). FI and WI were measured 3 times a day at 0700 h (Period 1; P1), 1200 h (P2) and 1700 h (P3), while BW was recorded daily. Blood samples were collected on D-1 and D5. Bird behavior (pecking, sitting and standing) was evaluated for 9 h on D2. Data were analyzed using a randomized complete block design with repeated measures over time. Orthogonal polynomial contrasts were used to determine linear and quadratic effects of increasing levels of capromorelin. Polynomial contrasts showed that capromorelin doses linearly increased FI (P = 0.002) and ADG (P = 0.019). There were no treatment, day or treatment x d interactions on glucose, ghrelin and GH concentrations. However, there was a treatment x d interaction (P = 0.041) on insulin concentrations. Concentrations of insulin were higher on D5 for the 0 and 12 mg/kgBW/d treatments as compared with D-1. Polynomial contrasts showed that capromorelin doses linearly increased number of pecks/h (P = 0.018). Per hour FI and WI was higher during P1 (i.e., 0700-1200) as compared to P2 and P3 (P < 0.001). Our observations suggest that capromorelin linearly increases feed intake; thus, the same effect of that reported in mammalian species.
胃饥饿素是一种在哺乳动物中诱导食欲增强作用的激素。然而，在禽类中，关于胃饥饿素对采食量（FI）的影响，研究结果稀少且相互矛盾。因此，我们评估了胃饥饿素受体激动剂（卡莫瑞林）对肉鸡的采食量、平均日增重（ADG）、饮水量（WI）、动物行为以及胃饥饿素、葡萄糖、生长激素（GH）和胰岛素浓度的影响。1日龄雄性肉鸡按照行业推荐进行饲养。在4周龄时（实验第0天；D0），根据体重将鸡只进行分组，并在两项相同的试验中随机分配到3种处理组。对照组鸡只接受含0 mg/kg体重/天卡莫瑞林的赋形剂对照溶液。处理2组和处理3组的鸡只分别接受目标剂量为6或12 mg/kg体重/天的卡莫瑞林（n = 27）。每天在0700时（第1阶段；P1）、1200时（P2）和1700时（P3）测量3次采食量和饮水量，同时每天记录体重。在D - 1和D5采集血样。在D2对鸡只行为（啄食、坐立和站立）进行9小时的评估。数据采用随机完全区组设计并随时间进行重复测量分析。使用正交多项式对比来确定卡莫瑞林水平增加的线性和二次效应。多项式对比显示，卡莫瑞林剂量线性增加采食量（P = 0.002）和平均日增重（P = 0.019）。在葡萄糖、胃饥饿素和生长激素浓度方面，不存在处理、日或处理×日的交互作用。然而，在胰岛素浓度方面存在处理×日的交互作用（P = 0.041）。与D - 1相比，0和12 mg/kg体重/天处理组在D5时胰岛素浓度更高。多项式对比显示，卡莫瑞林剂量线性增加每小时啄食次数（P = 0.018）。与P2和P3相比，P1期间（即0700 - 1200）每小时的采食量和饮水量更高（P < 0.001）。我们的观察结果表明，卡莫瑞林线性增加采食量；因此，与在哺乳动物中报道的效果相同。
