Earlier weaning of calves from Nellore cows and its effects on the fetal programming and on the produtive and reprodutive performance of the next progeny

• Grant number: 17/18937-0
• Support Opportunities: Research Projects - Thematic Grants
• Duration: May 01, 2020 - April 30, 2025
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Production
• Principal Investigator: Paulo Roberto Leme
• Grantee: Paulo Roberto Leme
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Pesquisadores principais:( Atuais ): Guilherme Pugliesi
• Pesquisadores principais:( Anteriores ): Arlindo Saran Netto
• Associated researchers: Arlindo Saran Netto ; Guilherme Pugliesi ; Heidge Fukumasu ; José Bento Sterman Ferraz ; Miguel Henrique de Almeida Santana ; Paulo Gustavo Macedo de Almeida Martins ; Philipe Moriel ; Pietro Sampaio Baruselli ; Rodrigo Silva Goulart ; Saulo da Luz e Silva
• Associated grant(s): 22/15757-9 - Scientific collaboration for fetal programing in cattle, AV.EXT
• Associated scholarship(s): 22/14260-3 - Feed efficiency in beef cattle: a phenomic approach to point-of-care test prototyping, BP.DR; 22/10479-0 - Early preceding weaning and its effect on fetal programming of calves on performance, metabolic profile, carcass composition and meat quality of Nellore cattle., BP.DR; 22/13791-5 - Effects of early weaning on fetal programming of gonadal development traits in Nelore females, BP.IC; + associated scholarships 22/05541-9 - Prospecting for viruses and ruminal mobile elements in Nellore cattle associated with feed efficiency, BP.MS; 22/03571-8 - Early weaning of Nelore cows and its effect on fetal programming and the productive and reproductive performance of the next progeny, BP.PD; 21/11637-6 - Productive performance of calves early weaned or at the conventional time, BP.IC; 21/12326-4 - Reproductive efficiency of females bovine animals that had early or conventional weaning of the previous offspring, BP.IC; 20/13311-8 - Effect of early weaning of Nelore calves during growing phase in pastures, BP.TT; 20/11136-4 - Effects of early weaning in Nelore cows on productive performance and carcass characteristics of weaned calves and on next progeny, BP.PD; 20/11203-3 - Effect of early weaning of Nelore calves on their productive performance, BP.TT - associated scholarships

Abstract

The overall objective presented in this proposal will be to evaluate the effects of anticipating the weaning (150 days vs. 240 days) of calves derived from beef cows on reproductive performance, and weaned calves and next progeny calves performance. A total of 200 pregnant cow-calf pairs (100 primiparous cows and 100 pluriparous) will be selected from the herd and allotted into two groups: (1) anticipated weaning, in which steers and heifers will be weaned at 150 days of age, and (2) conventional weaning, in which steers and heifers will be weaned at 240 days of age. In the Exp. 1, steers weaned in the conventional way or anticipated will be evaluated during rearing phase and termination, and heifers will be evaluated according its reproductive capacity. In Exp. 2 and 3, the next progeny calves will be followed from birth until slaughter (Exp.2, males) or beginning of breeding season (Exp. 3, females). In Experiment 4, several reproductive characteristics will be evaluated in the dams during the next breeding season to detect the effects of weaning in the reproductive performance of cows. Therefore, this management will be evaluated in the previous progeny and in the next as well as in their mothers. In addition, it is intended to evaluate the effect of these two maternal conditions in primiparous and pluriparous cows. (AU)