Predicting feed intake and growth of nursing calves: model development and evaluation

• Grant number: 22/13862-0
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: December 20, 2022
• End date: April 19, 2023
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Arlindo Saran Netto
• Grantee: Geovana Camila Baldin
• Supervisor: Phillip Lancaster
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Institution abroad: Kansas State University, United States
• Associated to the scholarship: 21/11637-6 - Productive performance of calves early weaned or at the conventional time, BP.IC

Abstract

Environmental issues are increasingly being put on the agenda for discussion due to the uncontrolled use of resources and the exaggerated increase in greenhouse gas emissions. In this sense, discussions on how to improve livestock productivity to reduce methane emissions are being studied and put into practice, including in beef cattle raising. Since within the meat production cycle, the biggest obstacle is found in the rearing phase and in the cow-calf pair, the challenge is to seek alternatives that aim for higher production rates, but that are linked to sustainability. When the issue is to optimize the rearing phase, early weaning is a strategy that is being adopted to remove the calves' suckling in advance and thus improve the cow's body condition, returning to cyclicity faster for the next breeding season. On the other hand, that the calf is removed early, supplementation strategies are recommended pre- and post-weaning so that these animals do not suffer greater performance losses throughout their lives. Therefore, to improve the diet balance for suckling calves and better target the nutrients in the ration, some researchers are searching for equations that estimate the intake of concentrate by calves still in the suckling phase. The aim of this project is to develop prediction equations for estimating feed intake and growth of suckler calves, also involving a sustainable and economical approach. To observe the nutritional requirements, NASEM 2016 will be used, to estimate net energy intake and growth rate, comparing values found with the real ones and these will be used to develop new equations, all analyses will be performed with R software. For the weight and age at weaning performance results, 100-heard cow herd will be simulated 1000 times to create a population of results, with actual field data from CHAPS which will also be used to measure the accuracy of the prediction equations. (AU)