Calves Weaned and Backgrounded on Pasture Respond to Pasture Nutritive Value and Supplements

Abstract

Preconditioning reduces stress, maintains health, and adds value to feeder calves. Calf response to pasture nutritive value and supplementation was studied on 17 farms in 2002, 8 farms in 2003, and 9 farms in 2004. Calves were weaned in late August and backgrounded on pasture to mid‐October. Calves were fed a commercial concentrate (0.0 to 1.5% bodyweight [BW]), hay, and on some farms haylage, ground shelled corn (Zea mays L.), or soybean (Glycine max L.) hulls. Calf average daily gain (ADG) was evaluated across farms relative to animal, pasture, and supplement characteristics using multiple regressions. Commercial supplement intake, corn intake, and pasture total digestible nutrient (TDN) or pasture neutral detergent fiber (NDF) significantly influenced calf ADG. Based on regression coefficients, 4.4 lb of commercial supplement or 4.1 lb of corn were required to produce 1 lb of additional gain. Increasing pasture TDN or decreasing pasture NDF by 10 percentage units increased ADG 0.86 or 0.48 lb/day, respectively. Regressions were tested against 2004 data. Regression‐estimated gains were not significantly different from measured ADG 67% of the time. Calf performance during backgrounding can be cost effective when management ensures adequate pasture quantity and nutritive value and supplements are used judiciously relative to their cost and the value of calf gain.

Evaluation of forage-based weaning systems in spring-born cross-bred beef calves

“…Two important conclusions can be made from this observation: 1) preconditioning added net weight value to feeder calves only when they were early-weaned on commercial feed; and 2) calves can be safely earlyweaned on corn-based supplements without any deleterious effect on weight gain. These findings partly agree with the observations of Rayburn et al [12,15] that calves weaned on high quality pasture and fed high energy supplements such as ground shelled corn or commercial supplements were heavier when marketed. Preshipment weight gains of feeder calves were improved by preconditioning during the ranch weaning period in a previous similar study [16].…”

“…Marginal effects of early weaning and feed cost were used to evaluate net return per kg weight gain during the preconditioning period. Marginal values of gain were obtained from [15]. Sensitivity analyses were evaluated in cases where market prices and feed costs were projected to change over time.…”

“…Given the average cost of corn mix was $0.10/kg, the marginal cost of weight gain on corn mix would be $0.278 (128.7 kg/46.32 kg × $0.10). Given the marginal value of preconditioned calf is $1.76/kg [15], using corn mix returned $1.48/kg ($1.76 -$0.278). Similarly, the 52.27 kg gain from commercial feed cost $0.411/kg gain Table 4).…”

Visual Reference Guide for Estimating Legume Content in Pastures

“…T here are advantages to growing legumes with the grasses in pastures and hay fields. These include providing nitrogen for plant growth and increasing forage quality, thereby reducing fertilizer cost and enhancing animal performance (Blaser et al, 1969; Blaser and Colleagues, 1986; Rayburn et al, 2006).…”

Measuring Legume Content in Pastures Using Digital Photographs

“…daily gain by 0.50 lbs./day over that of straight grass pastures (Rayburn et al, 2006) Clipping and hand separation of samples is the standard method for evaluating botanical composition in pastures; however, this method is very time consuming, so it is seldom used. Other methods include dry-weight rank, DAFOR (dominant, abundant, frequent, occasional, rare ranking) scale, point-intercept, and line-intercept methods (Mannetje and Haydock, 1963;Abaye et al, 1995Abaye et al, , 1997Interagency Technical Team, 1996;Rayburn et al, 2007).…”