&lt;b&gt;Body size and its effects on productive efficiency of cows with predominant Nellore genetic composition

Gustavo Duarte Farias,Leonir Luiz Pascoal,Pablo Tavares Costa,João Restle,Liliane Cerdótes,Otoniel Geter Lauz Ferreira,Ricardo Zambarda Vaz

doi:10.4025/actascianimsci.v40i1.42532

Abstract

This study was developed to evaluate productive efficiency during the lactation period of cows with predominant Nellore genetic composition based on their body size. Cows were divided into the following categories: light (≤ 316 kg), moderate (≥ 317 and ≤ 400 kg), or heavy (≥ 401 kg). Body weight change and total gain from birth to 210 days of age of calves born from heavy cows (0.155±0.03 and 111.6±5.1 kg) were higher than those of calves born from light (0.064±0.03 and 91.0±4.3 kg) and moderate (0.144±0.03 and 97.7±4.0 kg) cows. Calf production index differed (p < 0.05) with the herd of heavy cows (93.5±3.2 kg), producing 57.4 and 19.7% more kilograms of calf than light (59.4±2.7 kg) and moderate (78.1±2.4 kg) cows, respectively. Heavy Nellore cows produce heavier calves and have a better reproductive performance, which lead to a better calf production index. However, they require a larger area for the same herbage allowance. Calves born from heavier Nellore cows gain more weight from birth to 210 days of age and are heavier from 210 to 270 days of age.

Highlights

The Brazilian meat-livestock industry has unsatisfactory production indices when compared with the main world producers (Ferraz & Felício, 2010)
Nellore is the most common breed in numerical terms, as it participates in over half of the herds as pure and crossbreds and corresponds to approximately 80% of the zebu animals raised in the country (Anuário da Pecuária Brasileira, ANUALPEC, 2017)
Calf production is the main stage of beef cattle production, and despite usually generating less profit than the backgrounding and finishing phases, it is the supporting basis for the maintenance of the activity (Christofari et al, 2008; Gomes, Abreu, Carvalho, & Zen, 2013)

Summary

Introduction

The Brazilian meat-livestock industry has unsatisfactory production indices when compared with the main world producers (Ferraz & Felício, 2010). Efficient beef production is essential for the success of the activity and for the industry to be able to meet the constantly growing demand for meat. In this regard, production-efficiency measures can be used as a low-cost strategy. The body size of a cow interferes with its production efficiency In this scenario, the adaptability of the animal to the feeding conditions, climate, and other resources of the production system in which it is inserted is a fundamental factor. Its nutritional requirements must be adjusted according to the availability of nutrients and type of environment (Simioni, 2003)

Methods

Results

Conclusion