Prepartum and/or postpartum supplementation with monensin-molasses multinutrient blocks to optimize fertility and calf performance in primiparous beef cows

• Published in: Animal bioscience 2022, Vol.35 (11), p.1675-1688
• Main Authors: Catussi, Bruna Lima Chechin, da Silva, Laisa Garcia, Schalch, Fernando Jose Junior, Auder, Rafaela Maria Sutiro Angelieri, Gomez, Juan Fernando Morales, Mingoti, Rodolfo Daniel, Morgulis, Sergio Carlos Franco, Baruselli, Pietro Sampaio
• Format: Article
• Language: Korean
• ISSN: 2765-0189; 2765-0235

Objective: Pregnant Nelore heifers (n = 417) were used to evaluate the effects of supplementation with monensin-molasses multinutrient block (B) during pre and/or postpartum on reproductive and progeny performance. Methods: Heifers were allocated in four treatments: i) CC: heifers received control supplement (C) in loose meal form (0.06% of body weight [BW] offered daily before and after parturition; n = 108); ii) CB: received C before parturition and B (0.07% of BW offered weekly after parturition; n = 117); iii) BC: received B before and C after parturition (n = 103) and iv) BB: received B before and after parturition (n = 89). During pre and postpartum periods, concentration of metabolites/hormones and cow/calf performance was evaluated over time. Cows were synchronized twice for fixed timed artificial insemination (FTAI) using an estradiol/progesterone-based protocol. Data was analyzed by orthogonal contrasts (C). Results: B increased pregnancy at first FTAI (p = 0.04) and overall pregnancy rate (C1: CC vs BB+BC+CB; p = 0.05). Supplemented cows had greater body condition score (BCS) only at parturition (D0; p = 0.04) and at D40 (p = 0.02). B increased BW (p = 0.03), glucose concentrations (p = 0.01) and subcutaneous fat thickness (p = 0.03) only at D40. Concentrations of insulin were higher in supplemented cows (p = 0.008). Calves born by cows supplemented before and after parturition (C2: BB vs BC+CB) were heavier at 80 (p