Vital, M.N.F.; Paiva, J.J.D.S.; Paixão, R.T.; Marcondes, M.I.; Silva Júnior, J.M.M.D.; Franco, M.O.; Detmann, E.; Sampaio, C.B. Performance and Metabolic Evaluation in Primiparous Beef Cows under Grazing with Different Ages at Breeding. Preprints2023, 2023052027. https://doi.org/10.20944/preprints202305.2027.v1
APA Style
Vital, M.N.F., Paiva, J.J.D.S., Paixão, R.T., Marcondes, M.I., Silva Júnior, J.M.M.D., Franco, M.O., Detmann, E., & Sampaio, C.B. (2023). Performance and Metabolic Evaluation in Primiparous Beef Cows under Grazing with Different Ages at Breeding. Preprints. https://doi.org/10.20944/preprints202305.2027.v1
Chicago/Turabian Style
Vital, M.N.F., Edenio Detmann and Cláudia B. Sampaio. 2023 "Performance and Metabolic Evaluation in Primiparous Beef Cows under Grazing with Different Ages at Breeding" Preprints. https://doi.org/10.20944/preprints202305.2027.v1
Abstract
The objective was to evaluate the metabolic and performance differences in primiparous Nellore cows, which became pregnant at 14 or 24 months. Thirty-eight primiparous Nellore cows, which were bred for first pregnancy at 14 or 24-mo of age, with 202 ± 5 days of gestation were divided into two treatments according to breeding age: 14 or 24 months in the breeding season. Cows were evaluated for weight, body condition score (BCS), carcass characteristics, milk yield and blood parameters: glucose, total proteins, albumin, urea, beta-hydroxybutyrate (β-OHB), non-esterified fatty acids (NEFA), progesterone, and for insulin-like growth factor-1 (IGF-1). There was an in-teraction (p < 0.01) between age at first pregnancy and time for body weight, where 24-mo cows were heavier, but both categories loss weight at parturition which concomitant decrease in the BCS (p < 0,01). However, BW of 24-mo remained stable (p > 0.05) after parturition. Milk yield was higher in 24-mo cows (p < 0.01). Interaction between sampling time and breading age was observed for Longissimus muscle area (p < 0.01) and tended for Longissimus muscle depth, where 24-mo cows had greater values in prepartum. Calves born from the cows bred at 24-mo, where was higher (p < 0.01) from 160 days of age until weaning at 240 days. Glucose, urea, total proteins, albumin and NEFA were affected (p < 0.01) by the parturition data-point. There was an interaction (p < 0.01) between breading age and sampling period for β-OHB. Progesterone concentration was greater in 24-mo cows (p < 0.01). It was concluded that primiparous cows that became pregnant at 14 or 24 months of age have different nutritional and metabolic responses.
Keywords
Bos indicus; Body condition; Primiparous cows; Reproductive efficiency; Supplementation
Subject
Biology and Life Sciences, Animal Science, Veterinary Science and Zoology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
,
