In the beef production system, 70-75% of the total dietary energy is used for maintenance (Ferrell and Jenkins 1984; NRC 1996; Montaldo-Bermudez et al. 1990). Thus, while only 5% of the total life cycle dietary energy consumption is used for protein deposition in beef cattle, swine and poultry are more efficient at 14 and 22%, respectively. The relatively large size, slow maturity and slow repr...

The efficiency of feed use is an important factor influencing costs of production. However, feed intake (FI) is generally difficult and costly to measure. In addition, feed intake per se is relatively meaningless unless taken in the context of prevailing environmental and physiological processes. For example, FI and its utilisation by animals is altered by climate, activity levels, disease and ...

Abstract The objective of this study was to evaluate weight gain, feed intake, and efficiency in beef heifers while consuming two diets divergent energy density. Fifty-four yearling Angus cross (initial body = 307.5 ± 30.35 kg) were subject sequential intake trials using SmartFeed individual measuring technology (C-Lock Inc., Rapid City, SD) drylot pens at the Oklahoma State University Range Co...

We report the genetic relationship between growth and bone quality traits in a random mating broiler control population. Traits studied were growth rates from week 0 to 4 [body weight gain (BWG) 0 to 4], from week 0 to 6 (BWG 0 to 6), and residual feed intake (RFI) from week 5 to 6 (RFI 5 to 6). Bone quality traits were obtained at 6 weeks of age. These traits were shank weight (SW), shank leng...

Because feed is the major cost to pork production, management practices and breeding strategies are aimed at optimizing feed intake. Knowledge about the shape of feed intake and feeding behavior curves may be of interest for optimization of lean meat production. This study investigated trends based on daily measurements of feeding behavior in 200 Duroc barrows, originating from 5 sires and 200 ...

Recording complex phenotypes on a large scale is becoming possible with the incorporation of recently developed new technologies. One these technologies use 3D cameras commercial farms to measure feed intake and body weight (BW) daily. Residual (RFI) has been proposed as proxy for efficiency in several species, including cattle, pigs, poultry. Dry matter BW records are required calculate RFI, t...

Social dynamics in group-housed animals can have important impacts on their welfare, feed efficiency, and production potential. Our objectives were to: 1) evaluate the effects of parity social grouping competition behavior, feeding patterns, 2) investigate cow-level relationships between production, efficiency. Fifty-nine Holstein cows (144.5 ± 21.8 starting DIM, mean SD) housed a freestall pen...

Data were collected over the first 4 generations of a divergent selection experiment for residual feed intake of Large White pigs having ad libitum access to feed. This data set was used to obtain estimates of heritability for residual feed intake and genetic correlations (r(a)) between this trait and growth, carcass, and meat quality traits. Individual feed intake of group-housed animals was m...

Thermoregulation is essential to piglets' neonatal survival. This study used infrared thermography (IRT) assess thermoregulation abilities of piglets from two lines divergent for residual feed intake (RFI). At birth, morphology (weight, length, width and circumference), vigour (respiration, mobility vocalisation), rectal temperature were recorded the 11th generation low RFI (LRFI, more efficien...