Effects of residual feed intake and dam body weight on replacement heifer intake, efficiency, performance, and metabolic response

Abstract

Thirty-eight Angus-based, crossbred, nulliparous beef heifers (BW = 280 ± 26.3 kg) sired by 2 Angus sires were used to determine if dam BW affected heifer performance, DMI, residual feed intake (RFI), and endocrine markers. Heifers were housed in individual pens (2.2 by 9.1 m) equipped with 2.2 m of bunk space and fed a diet (90.4% DM, 13.7% CP, 67.2% NDF, and 56.2% TDN) consisting of 87.2% bermudagrass hay and 12.8% liquid protein supplement for a 14-d adaption period and a 70-d feeding period. Individual daily feed intake was used to calculate RFI for each heifer, and heifer was the experimental unit. Two-day beginning and end BW were recorded and hip height was used to calculate frame score (FS). Heifer dams were assigned to a light (LIT; 544 ± 21.3 kg) or heavy (HEV; 621 ± 34.8 kg) BW group on the basis of mean BW at the beginning of their lactation period the previous year to determine differences in heifer offspring DMI and RFI. Based on heifer RFI ranking, heifers were classified as positive (POS; 0.34) or negative (NEG; –0.31) RFI and low (LOW; –0.45), medium (MED; 0.00), or high (HI; 0.49) RFI for analysis of BW, FS, BW gain, and DMI. There were no dam BW group × sire interactions (P > 0.10) for all independent variables. Beginning and end BW was greater (P < 0.05) for heifers out of HEV compared with LIT BW dams. Body weight gain, ADG, FS, DMI, and RFI were not significant (P > 0.10) for heifers out of HEV compared with LIT BW dams; however, a sire effect existed (P < 0.01) for BW gain, ADG, FS, and DMI. Among RFI classifications, beginning and end BW, BW gain, ADG, and FS were not different (P > 0.10) whereas DMI was greater (P = 0.03) among heifers in the POS compared with the NEG RFI group and greater (P = 0.01) among heifers in the MED and HI compared with LOW RFI group, respectively. Plasma insulin levels were greater (P = 0.03) in the NEG compared with the POS RFI heifers, and thyroxine (T4) levels were greater (P = 0.02) in the POS compared with the NEG RFI heifers. A positive relationship existed (P ≤ 0.05) between dam BW and heifer DMI (r = 0.42), beginning and end BW (r = 0.45 and 54), and FS (r = 0.58) and between RFI and d 70 triiodothyronine (r = 0.34), d 70 T4 (r = 0.35), and d 0 and 70 combined T4 (r = 0.32), respectively. Heifers out of dams from the HEV BW group were heavier and a positive correlation existed between dam BW and heifer BW, gain, DMI, and FS, which can impact selection goals for replacement heifers.

Association of residual feed intake with growth and slaughtering performance, blood metabolism, and body composition in growing lambs

“…In the later growth stages, Walker et al . found that the plasma level of T4 was not affected by BW but by RFI; this difference may be due to the role of thyroid hormones, as the developing heifers required thyroid hormones to remain active 35 . The results of previous studies are consistent with our findings that the plasma concentration of T4 was lower in ELow-RFI lambs than in EHigh-RFI lambs; thus, thyroid hormones are active in growing lambs.…”

Heritability estimation and genetic correlations for mature weight, visual scores, and growth traits in Nellore cattle

“…Moreover, pre-weaning nutrition and average daily gain (ADG) are strategies to improve the economic and biological efficiency of cow-calf production systems, allowing anticipation of age at first breeding to determine puberty in heifers. There is a positive correlation between BW of dams and of their respective daughters, which can influence selection goals for replacement heifers, thereby achieving a significant improvement in growth efficiency of heifers (Barcellos et al, 2014;Walker et al, 2015;Pereira et al, 2017).…”

Relationship of post-weaning growth and age at puberty in crossbred beef heifers

“…In the present study, we observed a correlation of -0.37 between the BCS and age of puberty indicating that the characteristics related to fat deposition influence puberty appearance. Walker et al (2015) observed that heifers from heavier dams showed that a positive correlation existed between dam and heifer body weight that can affect selection goals for replacement heifers. Our data suggest a close agreement with other studies about beef breeds, in which visual appraisal were measured on live animals (Robinson et al, 1993;Queiroz et al, 2011).…”