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Relationships among feeding behaviors and performance traits of growing and finishing phase Red Angus cattle
The progeny (n = 37) of Red Angus bulls were performance evaluated during both growing and finishing phase residual feed intake (RFI) tests. Data for RFI evaluation and 7 behavior traits were collected using a feed intake monitoring system (GrowSafe Systems) over standard 70 d RFI test periods for both phases (BW growing: initial 331± 28 kg, final 451 ± 37 kg; finish: initial 499 ± 39 kg; final 587 ± 44 kg). Seven feeding behavior traits: bunk visit frequency (BVFREQ), bunk visit duration (BVDUR), feed bout frequency (FBFREQ), feed bout duration (FBDUR), meal frequency (MFREQ), meal duration (MDUR), and average meal intake (AMINT) and their relationships with RFI, DMI, and ADG were evaluated. Dry matter intake was correlated with BVDUR and FBDUR (r = 0.44; P = 0.01 for both behaviors) during the growing phase. Residual feed intake and BVDUR or FBDUR showed little to moderate correlations in growing phase (r = 0.30; P = 0.07 and r = 0.27 P = 0.10, respectively). There were no significant correlations between ADG and the 7 behavior traits during the growing phase RFI test. However during the finishing phase RFI test, ADG was correlated with BVFREQ and FBFREQ (r = 0.43 P = 0.01 for both behaviors). Neither DMI nor RFI were correlated with any of the 7 feeding behavior traits during the finishing phase RFI test. Combining correlated traits into the RFI base model to predict DMI reduced the mean standard error by 13% for growing phase and 17% for finishing phase RFI tests. As these animals were offered different diets during growing and finishing phases (roughage-based vs. concentrate, respectively), the relative contribution of feeding behaviors in predicting DMI may be partially diet-type dependent. Inclusion of correlated feeding behaviors improved feed intake prediction by 13 to 17%, providing evidence that the study of behavior traits has potential to improve our understanding of the biological drivers of feed intake.
Keywords:
Red Angus, Feeding Behavior, RFI