Location: Reproduction ResearchTitle: Effects of sire breed, gender, and postnatal litter size on plasma concentrations of acyl ghrelin and its relationship with growth traits and feeding behavior in swine
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 12/16/2014
Publication Date: 3/1/2015
Citation: Lents, C.A., Brown-Brandl, T.M., Rohrer, G.A., Oliver, W.T., Freking, B.A. 2015. Effects of sire breed, gender, and postnatal litter size on plasma concentrations of acyl ghrelin and its relationship with growth traits and feeding behavior in swine [abstract]. Journal of Animal Science. 93(Supplement 2):148 (Abstract #333).
Technical Abstract: Feeding behavior is an important component of growth and feed efficiency in swine. Acyl ghrelin is a peptide produced in the stomach that is orexigenic. The role of ghrelin in regulating feeding behavior in swine under commercial conditions is unknown. The objective of this study was to determine the effect of sire breed, gender, and postnatal litter size on concentrations of acyl ghrelin in plasma and to determine the relationship of acyl ghrelin with growth traits and feeding behavior in pigs. Yorkshire-Landrace-Ducroc (Y-L-D) dams were AI with semen from Y, L, or D sires. Within 24 h of birth, pigs were cross fostered into large (L; >= 12 pigs) or small (S; <= 9 pigs) litters. At 8 wk of age, pigs (n = 240) were blocked by sire breed, gender, and litter size and assigned to pens (n = 6) containing commercial feeders modified with a system to monitor feeding behavior. Total time eating, number of daily meals, and duration of meals were recorded for each individual pig. Body weight was recorded every 4 wk. Back fat (BF) and loin eye area (LEA) were recorded at the conclusion of the 12-wk feeding study. A blood sample was collected at week 8 of the study to quantify concentrations of acyl ghrelin in plasma by RIA. Barrows had greater total time eating (P < 0.01), grew faster (P < 0.01), were heavier (P < 0.05) and fatter (P < 0.001) with larger LEA (P < 0.05) than gilts. The pigs from S litters grew faster (P < 0.04), were heavier (P < 0.02) and fatter (P < 0.05) with larger LEA (P < 0.05) than pigs from L litters. Plasma concentrations of acyl ghrelin were not affected by sire breed, gender, or postnatal litter size. Concentrations of acyl ghrelin in plasma were positively associated with number of daily meals (P < 0.01) and negatively associated with meal duration (P < 0.03), BF (P < 0.05), and ADG at weeks 4 and 8 of the study (P < 0.01). Variation in concentrations of acyl ghrelin was not associated with gender or early postnatal development in this study. A larger number of short duration meals may indicate that pigs with greater concentrations of acyl ghrelin consumed less total DM, which likely explains why they were leaner and grew more slowly.