Optimizing reproductive efficiency is crucial in sustaining a successful cattle operation. However, optimizing reproductive performance in young range beef cows is often not captured due to an inability to meet the increased physiological demands. The objective of this study was to determine the impact of feed additives on reproductive performance, cow body weight (BW), body condition score (BCS), and calf growth in young, range beef cows. Data were collected from 2- and 3-year-old range cows (n = 189) from the March-calving herd at the University of Nebraska Gudmundsen Sandhills Laboratory (GSL) located near Whitman, NE over a three-year period (2019-2021). Cows were individually supplemented 908 g/d with one of two 30% crude protein supplement treatments with the addition of either: 1) 160 mg·cow-1·d-1 of rumensin (MON; Elanco Animal Health) or 2) 40 g·cow-1·d-1 of propionate salt (CAP; NutroCal 100; Kemin Animal Nutrition and Health). Supplementation was initiated approximately 7 d after calving and continued for an average of 70 d. Cow BW and BCS were collected weekly from calving to the start of breeding and then again at weaning. On approximately d 60 postpartum, milk production was measured by a modified weigh-suckle-weight technique. Cows were exposed to fertile bulls for a 45-d breeding season starting in June of each year. Cow BW (P ≥ 0.19) and BCS (P ≥ 0.11) were not affected by postpartum supplementation during the study. However, cows receiving CAP did lose more BW (P = 0.04; -7 vs -2 kg for CAP and MON; respectively) from calving to breeding than their counterpart. Calf BW at birth, weaning, or 205-d weight were not impacted (P ≥ 0.68) by the postpartum supplementation strategy. Twenty-four-hour milk production and milk components (fat, solids-non-fat, urea nitrogen) were not influenced (P > 0.21) by postpartum supplementation strategy. However, cows receiving CAP supplement had an increase (P = 0.04; 5.40 vs 5.31% for CAP and MON; respectively) in milk lactose percentage and tended (P = 0.06; 2.56 vs 2.68% for CAP and MON; respectively) to have lower milk protein percentage than their counterpart. Cows receiving CAP supplementation had an increase (P = 0.04; 89 vs 80% for CAP and MON; respectively) in overall pregnancy rate. This study implies that young postpartum cows fed additional glucogenic precursors in the form of propionate salts may increase reproductive efficiency without impacting a change in body weight or body condition score.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.