Nishimura Thiago Kan, de Paula Carlis Matheus Sousa, Matos Ana Clara Degan, Feltrin Isabella Rio, Goulart Rodrigo Silva, Zamudio Germán Darío Ramírez, Silva Saulo Luz, Netto Arlindo Saran, Leme Paulo Roberto, Pugliesi Guilherme
Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Pirassununga, 13635-900, Brazil.
Department of Animal Science, School of Animal Science and Food Engineering, University of São Paulo, São Paulo, Pirassununga, 13635-900, Brazil.
Trop Anim Health Prod. 2025 Jun 25;57(6):283. doi: 10.1007/s11250-025-04535-z.
This study aimed to compare the effects of early weaning (EW; 150 days) and conventional weaning (CW; 240 days) during early pregnancy on the postnatal metabolism, development, and productive performance of female calves born from secondiparous (SEC) and multiparous (MULT) cows. Fifty-five Nelore female calves were evaluated: 25 from EW cows (10 SEC, 15 MULT) and 30 from CW cows (15 SEC, 15 MULT). From 90 to 150 days of age, all calves received creep feed (5 g/kg body weight [BW]). After weaning, calves were maintained on pasture and supplemented with 10 g/kg of BW of concentrate until 16 months (mo) of age. From 12 to 16 mo, heifers were assessed every 28 ± 3 days for BW, body condition score (BCS), and average daily gain (ADG), which was calculated from serial weight records. Carcass traits (ribeye area [REA], backfat thickness [BFT], and rump fat thickness [RFT]) were measured via ultrasound. Blood samples were collected to determine serum concentration of IGF-I, leptin, and plasma glucose. At 5 and 14 mo, a subgroup of 22 heifers (n = 10 for EW and 12 for CW) was selected for liver biopsy to assess the gene expression of IGF-I, IGFBP, and GHR. No significant interactions were found between dam parity, weaning strategy, or time for BW, BCS, ADG, REA, serum IGF-I, leptin, and plasma concentration for glucose (P > 0.1). A significant effect of time (P < 0.05) indicated increased in BW, BCS, LMA, BFT, and RTF throughout the experimental period. Heifers from MULT cows were 2.67 kg heavier between 13 to 15 mo than those from SEC cows (P = 0.04). Dam parity also influenced BCS (P = 0.01), with MULT-derived heifers presenting higher BCS than those from SEC cows. For carcass traits, a significant dam parity x weaning interaction was observed for RTF (P = 0.04), indicating that EW-SEC heifers had lower rump fat deposition compared to EW-MULT and CW heifers. IGF-I gene expression was 1.4-fold greater (P = 0.01) at 5 mo compared 14 mo. For IGFBP, a dam parity × time interaction (P = 0.05) revealed that heifers from MULT cows had a 1.8-fold higher expression at 14 mo than at 5 mo. In conclusion, early weaning in the preceding lactation did not negatively affect the subsequent offspring's performance or metabolic profile, except for a reduction in rump fat thickness in EW-SEC heifers.
本研究旨在比较妊娠早期进行早期断奶（EW；150天）和传统断奶（CW；240天）对经产（SEC）和多产（MULT）母牛所生雌性犊牛产后代谢、发育及生产性能的影响。对55头内洛尔雌性犊牛进行了评估：25头来自EW母牛（10头SEC，15头MULT），30头来自CW母牛（15头SEC，15头MULT）。在90至150日龄期间，所有犊牛均采食开食料（5克/千克体重[BW]）。断奶后，犊牛在牧场饲养，并补充10克/千克BW的精料，直至16月龄（mo）。在12至16 mo期间，每隔28±3天对小母牛进行体重（BW）、体况评分（BCS）和平均日增重（ADG）评估，ADG根据连续体重记录计算得出。通过超声测量胴体性状（眼肌面积[REA]、背膘厚度[BFT]和臀脂厚度[RFT]）。采集血样以测定血清IGF-I、瘦素和血浆葡萄糖浓度。在5 mo和14 mo时，选取22头小母牛组成的亚组（EW组10头，CW组12头）进行肝脏活检，以评估IGF-I、IGFBP和GHR的基因表达。未发现母本胎次、断奶策略或时间对BW、BCS、ADG、REA、血清IGF-I、瘦素和血浆葡萄糖浓度有显著交互作用（P>0.1）。时间的显著影响（P<0.05）表明，在整个实验期间BW、BCS、LMA、BFT和RTF均有所增加。MULT母牛所生小母牛在13至15 mo期间比SEC母牛所生小母牛重2.67千克（P=0.04）。母本胎次也影响BCS（P=0.01），MULT衍生的小母牛BCS高于SEC母牛所生小母牛。对于胴体性状，观察到RTF存在显著的母本胎次×断奶交互作用（P=0.04），表明EW-SEC小母牛的臀脂沉积低于EW-MULT和CW小母牛。与14 mo相比，IGF-I基因表达在5 mo时高1.4倍（P=0.01）。对于IGFBP，母本胎次×时间交互作用（P=0.05）表明，MULT母牛所生小母牛在14 mo时的表达比5 mo时高1.8倍。总之，前一胎次的早期断奶除了使EW-SEC小母牛的臀脂厚度降低外，并未对后续后代的性能或代谢特征产生负面影响。
