Extended effects of postweaning management in southeastern beef calves

Abstract

Objective

Understanding the effects of postweaning management strategy on calf performance and health can help producers add value to their operations and further strengthen the viability of the beef supply chain. Our objective with this study was to evaluate the effects of weaning and postweaning management practices and potential carryover effects on calf immune system viability and performance through the feedyard finishing phase.

Materials and Methods

A 2-yr study was conducted using 429 steer calves from 3 Auburn University research farms. Calves were randomly assigned based on weaning weights to 1 of 3 different weaning method groups: fence-line weaning, nose-flap weaning, or abrupt weaning. After the weaning period (14 d), calves were brought to a centralized farm and began a 60-d backgrounding period where they were randomized according to previous weaning management, farm of origin, and BW to 1 of 3 nutritional management strategies in a 3 × 3 split-plot design: cool-season baleage and 1% BW dried distillers grain (DDGS), bermudagrass hay and 1% BW DDGS, or grazing of mixed warm-season annuals and 1% BW DDGS. Body weights were collected throughout the trial to measure growth and performance. Blood samples were collected throughout the backgrounding period to measure vaccination response. Following backgrounding calves were transported to a commercial feedyard and followed until finishing.

Results and Discussion

Fence-line-weaned calves had the greatest ADG (P = 0.02) in the first 30 d of the backgrounding period regardless of backgrounding diet type. Calves fed the bermudagrass-hay-based diet also had a greater ADG (P < 0.0001) than both the grazing and baleage diet groups in the first 30 d of backgrounding. Steers on both the warm-season annual grazing and cool- season baleage diets supported greater ADG (P = 0.0041) during the last 30 d of the backgrounding period.

Implications and Applications

Results indicate that weaning and backgrounding management strategies may influence calf performance during the transition period into the postweaning phase and performance in the feedyard phase.