|ARTEGOITIA, VIRGINIA - University Of Nebraska|
|LEWIS, RON - University Of Nebraska|
|King, David - Andy|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 4/21/2016
Publication Date: 7/11/2016
Citation: Artegoitia, V.M., Foote, A.P., Lewis, R.M., King, D.A., Shackelford, S.D., Wheeler, T.L., Freetly, H.C. 2016. Endocannabinoid concentrations in plasma associated with feed efficiency and carcass composition on crossbreed steers [abstract]. Journal of Animal Science. 94 (E-Supplement 5):704.
Technical Abstract: Endocannabinoids, including anandamide (AEA) and 2-arachidonoylglycerol (2-AG), are a class of endogenous lipid mediators that activate cannabinoids receptors and may be involved in the control of feed intake and energy metabolism. The objective of this study was to quantify AEA and 2-AG in plasma and identify possible associations with production traits and carcass composition in finishing beef steers. Individual DMI and BW gain was measured on 140 crossbred steers for 105 d on a finishing ration. Blood samples were collected on d 84 of the experiment, which was 40 d before slaughter. Variables were analyzed using Pearson CORR procedure of SAS. Mean endocannabinoid concentrations in plasma were 4.48 ± 1.82 ng/mL and 0.43 ± 0.24 ng/mL for AEA and 2-AG, respectively. The AEA concentration was positively correlated with G:F ratio (r = 0.20, P = 0.02), indicating that more efficient animals were correlated with higher AEA plasma concentration. Nevertheless, AEA concentration was negatively correlated with metabolic BW at the midpoint of the experiment (r = -15, P = 0.07) and initial BW (r = -0.19, P = 0.03). In addition, AEA concentration was negatively correlated with the 12th rib fat thickness (r = 0.17, P = 0.07); but no correlation was found with USDA–calculated yield grade (r = -0.14, P = 0.11), or marbling score (r = 0.05, P = 0.54). The concentration of 2-AG was positively correlated with AEA (r = 0.21, P = 0.01); however, 2-AG concentration was not correlated with parameters of feed efficiency or carcass composition. In summary, the present study is the first to report plasma concentration of endocannabinoids in steers. These results provide evidence that plasma concentration of a key endocannabinoid, AEA, was favorably correlated with feed efficiency and fat thickness on crossbred steers at finishing.