育肥牛的干物质摄入量、生长及胴体特征与循环中活性和总胃饥饿素浓度的关联

Association of circulating active and total ghrelin concentrations with dry matter intake, growth, and carcass characteristics of finishing beef cattle.

作者信息

Foote A P, Hales K E, Lents C A, Freetly H C

机构信息

U.S. Meat Animal Research Center, ARS, USDA, Clay Center, NE 68933-0166

U.S. Meat Animal Research Center, ARS, USDA, Clay Center, NE 68933-0166.

出版信息

J Anim Sci. 2014 Dec;92(12):5651-8. doi: 10.2527/jas.2014-8291.

DOI:10.2527/jas.2014-8291

PMID:25414111

Abstract

Ghrelin is a gut peptide that when acylated is thought to stimulate appetite. Circulating ghrelin concentrations could potentially be used as a predictor of DMI in cattle. The objective of this experiment was to determine the association of circulating ghrelin concentrations with DMI and other production traits. Steers and heifers were fed a finishing diet, and individual intake was recorded for 84 d. Blood samples were collected via jugular venipuncture following the DMI and ADG measurement period. Plasma active ghrelin and total ghrelin were quantified using commercial RIA. Active ghrelin was not correlated to DMI (P=0.36), but when DMI was modeled using a multivariate analysis including plasma metabolites and sex, active ghrelin was shown to be positively associated with DMI (P<0.01) and accounted for 6.2% of the variation accounted for by the regression model (R2=0.33). Total ghrelin was negatively correlated to DMI (P<0.01), but was not significant in a multivariate regression analysis (P=0.13). The ratio of active:total ghrelin was positively associated with DMI (P<0.01) and accounted for 10.2% of the variation in the model (R2=0.35). Active ghrelin was positively associated with ADG (P<0.05), while total ghrelin was negatively associated with ADG (P<0.01), and the ratio of active:total ghrelin was positively associated with ADG (P<0.01). Active ghrelin was not associated with G:F (P=0.88), but total ghrelin concentrations were negatively associated with G:F (P<0.01) and accounted for 10.24% of the variation (R2=0.25). Heifers consumed less feed than steers (P<0.01), tended to have greater active ghrelin concentrations (P=0.06), and had greater total ghrelin concentrations than steers (P=0.04). Total ghrelin concentrations were not different between sire breeds (P=0.80), but active ghrelin concentrations and the ratio of active:total ghrelin differed between breeds (P<0.01), indicating that genetics have an effect on the amount and form of circulating ghrelin. Total ghrelin concentrations tended (P=0.08) to be correlated with HCW, but no other carcass characteristics were correlated with active or total ghrelin concentrations (P>0.10). Results indicated that ghrelin concentrations are associated with DMI in beef cattle and that there is genetic variation that leads to differences in the amount and form of circulating ghrelin which could contribute to variation observed in DMI of beef cattle.

摘要

胃饥饿素是一种肠道肽，酰化后的胃饥饿素被认为会刺激食欲。循环中的胃饥饿素浓度有可能被用作牛干物质采食量（DMI）的预测指标。本实验的目的是确定循环胃饥饿素浓度与DMI及其他生产性状之间的关联。给公牛和小母牛饲喂育肥日粮，并记录个体84天的采食量。在测量DMI和平均日增重（ADG）之后，通过颈静脉穿刺采集血样。使用商业放射免疫分析（RIA）对血浆活性胃饥饿素和总胃饥饿素进行定量。活性胃饥饿素与DMI不相关（P = 0.36），但当使用包括血浆代谢物和性别的多变量分析对DMI进行建模时，活性胃饥饿素显示与DMI呈正相关（P < 0.01），并占回归模型解释变异的6.2%（R2 = 0.33）。总胃饥饿素与DMI呈负相关（P < 0.01），但在多变量回归分析中不显著（P = 0.13）。活性胃饥饿素与总胃饥饿素的比值与DMI呈正相关（P < 0.01），并占模型变异的10.2%（R2 = 0.35）。活性胃饥饿素与ADG呈正相关（P < 0.05），而总胃饥饿素与ADG呈负相关（P < 0.01），活性胃饥饿素与总胃饥饿素的比值与ADG呈正相关（P < 0.01）。活性胃饥饿素与料重比（G:F）不相关（P = 0.88），但总胃饥饿素浓度与G:F呈负相关（P < 0.01），并占变异的10.24%（R2 = 0.25）。小母牛的采食量低于公牛（P < 0.01），活性胃饥饿素浓度往往更高（P = 0.0６），总胃饥饿素浓度也高于公牛（P = 0.04）。父本品种间总胃饥饿素浓度无差异（P = 0.80），但活性胃饥饿素浓度以及活性胃饥饿素与总胃饥饿素的比值在品种间存在差异（P < 0.01），这表明遗传因素对循环胃饥饿素的量和形式有影响。总胃饥饿素浓度与热胴体重（HCW）有相关趋势（P = 0.08），但没有其他胴体特征与活性或总胃饥饿素浓度相关（P > 0.10）。结果表明，胃饥饿素浓度与肉牛的DMI相关，并且存在遗传变异导致循环胃饥饿素的量和形式存在差异，这可能是肉牛DMI出现差异的原因。