TY - JOUR
T1 - Relationship of leptin concentrations with feed intake, growth, and efficiency in finishing beef steers
AU - Foote, A. P.
AU - Hales, K. E.
AU - Kuehn, L. A.
AU - Keisler, D. H.
AU - King, D. A.
AU - Shackelford, S. D.
AU - Wheeler, T. L.
AU - Freetly, H. C.
N1 - Publisher Copyright:
© 2015 American Society of Animal Science. All rights reserved.
PY - 2015/9/8
Y1 - 2015/9/8
N2 - The objective of this experiment was to determine the association of serum leptin concentrations with production measures including DMI, ADG, and G:F as well as carcass characteristics in genetically diverse finishing beef steers. Three cohorts of steers (n = 473 total) were individually fed a finishing ration for 92, 64, and 84 d for cohort 1, 2, and 3, respectively. Serum was collected on d 42, 22, and 19 of the experiment for cohort 1, 2, and 3, respectively. Leptin concentrations were positively correlated to DMI (r = 0.21, P < 0.01) but negatively correlated to grams DMI per kilogram initial BW (r = –0.21, P < 0.01). Leptin concentrations were also negatively correlated to ADG and G:F (P < 0.01). Leptin concentrations were positively correlated to 12th-rib fat thickness, yield grade, and marbling score (P < 0.01) and negatively correlated to LM area (P < 0.01). Using a mixed model analysis (SAS 9.3; SAS Inst. Inc., Cary, NC) to account for breed effects, leptin concentrations were positively associated with DMI (P = 0.01) and accounted for 1.10% of the variance. However, if initial BW and yield grade were included as covariates to account for body size and fatness, leptin was negatively associated with DMI (P = 0.02) and accounted for 0.54% of the variance. Regardless of covariates included in the model, leptin was negatively associated with ADG (P < 0.01) and G:F (P < 0.01) and accounted for 2.62 and 7.87% of the variance for ADG and G:F, respectively. Leptin concentrations were also positively associated with 12th-rib fat thickness, yield grade, and marbling score (P < 0.01) and accounted for 14.74, 12.74, and 6.99% of the variance for 12thrib fat, yield grade, and marbling score, respectively. Leptin concentrations could be a useful physiological marker for growth and feed efficiency of finishing beef cattle. Genetic influences on the biology of leptin also need to be considered when using leptin as physiological marker for production measures.
AB - The objective of this experiment was to determine the association of serum leptin concentrations with production measures including DMI, ADG, and G:F as well as carcass characteristics in genetically diverse finishing beef steers. Three cohorts of steers (n = 473 total) were individually fed a finishing ration for 92, 64, and 84 d for cohort 1, 2, and 3, respectively. Serum was collected on d 42, 22, and 19 of the experiment for cohort 1, 2, and 3, respectively. Leptin concentrations were positively correlated to DMI (r = 0.21, P < 0.01) but negatively correlated to grams DMI per kilogram initial BW (r = –0.21, P < 0.01). Leptin concentrations were also negatively correlated to ADG and G:F (P < 0.01). Leptin concentrations were positively correlated to 12th-rib fat thickness, yield grade, and marbling score (P < 0.01) and negatively correlated to LM area (P < 0.01). Using a mixed model analysis (SAS 9.3; SAS Inst. Inc., Cary, NC) to account for breed effects, leptin concentrations were positively associated with DMI (P = 0.01) and accounted for 1.10% of the variance. However, if initial BW and yield grade were included as covariates to account for body size and fatness, leptin was negatively associated with DMI (P = 0.02) and accounted for 0.54% of the variance. Regardless of covariates included in the model, leptin was negatively associated with ADG (P < 0.01) and G:F (P < 0.01) and accounted for 2.62 and 7.87% of the variance for ADG and G:F, respectively. Leptin concentrations were also positively associated with 12th-rib fat thickness, yield grade, and marbling score (P < 0.01) and accounted for 14.74, 12.74, and 6.99% of the variance for 12thrib fat, yield grade, and marbling score, respectively. Leptin concentrations could be a useful physiological marker for growth and feed efficiency of finishing beef cattle. Genetic influences on the biology of leptin also need to be considered when using leptin as physiological marker for production measures.
KW - Feed efficiency
KW - Growth
KW - Physiological markers
UR - http://www.scopus.com/inward/record.url?scp=84974678411&partnerID=8YFLogxK
U2 - 10.2527/jas.2015-9339
DO - 10.2527/jas.2015-9339
M3 - Article
C2 - 26440340
AN - SCOPUS:84974678411
SN - 0021-8812
VL - 93
SP - 4401
EP - 4407
JO - Journal of animal science
JF - Journal of animal science
IS - 9
ER -