Ganho genético e avaliação econômica de sistemas produtivos de gado de corte sob diferentes técnicas reprodutivas e com cruzamento industrial
Carregando...
Arquivos
Data
2018-04-26
Autores
Costa, Henrique José Urzedo
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Biotécnicas reprodutivas e cruzamento constituem importantes ferramentas para o aumento da eficiência econômica e produtiva em bovinos de corte. A determinação da intensidade do uso dessas biotécnicas e o cruzamento, nas diferentes condições ambientais, de manejo e mercado, são fundamentais para otimizar a relação custo-benefício de sua adoção, visando aumentar a rentabilidade do sistema produtivo. Objetivou-se com este estudo estimar o ganho genético e econômico da utilização de diferentes biotécnicas reprodutivas e cruzamento, em um sistema produtivo de bovinos de corte, usando simulações determinísticas. O estudo foi baseado em um sistema de produção com capacidade para 1000 UA (UA = 450kg de peso vivo), adotando pastejo contínuo e taxa de lotação variável. O primeiro cenário foi caracterizado pela inseminação artificial (IA) (sêmen Nelore) e repasse com monta natural (MN) com touros Nelore. Os outros cenários envolveram o uso de ao menos uma dessas técnicas: inseminação artificial em tempo fixo (IATF), fertilização “in vitro” (FIV) e cruzamento de vacas Nelore com touros Angus (sêmen). Os parâmetros econômicos foram extraídos de instituições da região central do Brasil. Foi estimada a porcentagem de produção de animais superiores e o ganho genético, e calculado para o curto (5 anos), médio (10 anos) e longo (15 anos) prazos. Indicadores econômicos como quantidade de progênie produzida, custo total estimado a desmama e ao abate, lucro estimado a desmama e ao abate e taxa de desfrute também foram calculados. Dentre todos os cenários simulados aqueles que utilizaram a IATF são os que apresentaram, na maioria dos casos, lucro líquido superior. O cenário com uso de inseminação artificial convencional (IA) obteve receitas intermediárias, mas também custos intermediários. Os cenários que utilizaram a FIV geralmente apresentaram maior custo de produção agregado e produziram menor quantidade de bezerros. O cenário que utilizou o cruzamento industrial em conjunto com IATF apresentou resultados econômicos positivos, porém registrou menor ganho genético calculado, devido a quantidade de fêmeas Nelore produzidas. Portanto, se for considerada a venda dos animais a desmama, o cenário com uso de inseminação artificial comum (IA) é o mais indicado, pois combina resultados econômicos intermediários com índices de ganho genético intermediários. Para a comercialização dos animais ao abate, a IATF (Nelore) é o cenário mais indicado, pois além de produzir o maior lucro observado (5,47@/ha) (ha = hectare) proporciona valores intermediários de ganho genético (10,60% e 9,70% para machos e fêmeas, respectivamente).
– Reproductive biotechniques and crossbreeding are important tools for increasing economic and productive efficiency in beef cattle. The determination of the intensity of use of these biotechniques and the crossbreeding, in the different environmental, management and market conditions, are fundamental to certify a better cost-benefit relation of its adoption, in order to increase the profitability of the production system. The objective of this study was to estimate the genetic and economic gain using different reproductive biotechniques and crossbreeding for a production system of beef cattle by means of deterministic simulations. The study was based on a production system with capacity for 1000 AU (AU = 992,08 pounds of body weight), adopting the continuous grazing and variable stocking rate. The first scenario was characterized by artificial insemination (AI) (Nellore) and natural mating (NM) with Nellore bulls. The other scenarios involved the use of at least one of these techniques: fixed-time artificial insemination (FTAI), in vitro fertilization (IVF), and crossbreeding of Nellore cows with Angus bulls. The economic values were extracted from institutions of the central region of Brazil. The percentage of production of superior animals and genetic gain were calculated in the short (5 years), medium (10 years) and long (15 years) time. Economic indicators such as amount of progeny produced, estimated total cost of weaning and slaughter, estimated profit of weaning and slaughter and offspring rate were also calculated. Among all the simulated scenarios, those who used the FTAI are those that presented a higher profit in almost all cases. The scenario using conventional artificial insemination (AI) obtained intermediate income, but also intermediate costs. The scenarios that used IVF generally presented higher cost of production and produced smaller numbers of calves. The scenario that used the crossbreeding showed positive economic results, but it registered the lowest genetic gain calculated, due to the smaller quantity of Nellore females produced. Therefore, considering the sale of animals at weaning, the scenario with the use of conventional artificial insemination (AI) is the most appropriate, since it combines intermediate economic results with intermediate rates of genetic gain. In order to commercialize the animals at slaughter, the FTAI (Nellore) is the most appropriate scenario, since it produces the highest observed profit (5.47 at/ha) (ha = hectare) and provides intermediate values of genetic gain (10.60% and 9.70% for males and females, respectively)
– Reproductive biotechniques and crossbreeding are important tools for increasing economic and productive efficiency in beef cattle. The determination of the intensity of use of these biotechniques and the crossbreeding, in the different environmental, management and market conditions, are fundamental to certify a better cost-benefit relation of its adoption, in order to increase the profitability of the production system. The objective of this study was to estimate the genetic and economic gain using different reproductive biotechniques and crossbreeding for a production system of beef cattle by means of deterministic simulations. The study was based on a production system with capacity for 1000 AU (AU = 992,08 pounds of body weight), adopting the continuous grazing and variable stocking rate. The first scenario was characterized by artificial insemination (AI) (Nellore) and natural mating (NM) with Nellore bulls. The other scenarios involved the use of at least one of these techniques: fixed-time artificial insemination (FTAI), in vitro fertilization (IVF), and crossbreeding of Nellore cows with Angus bulls. The economic values were extracted from institutions of the central region of Brazil. The percentage of production of superior animals and genetic gain were calculated in the short (5 years), medium (10 years) and long (15 years) time. Economic indicators such as amount of progeny produced, estimated total cost of weaning and slaughter, estimated profit of weaning and slaughter and offspring rate were also calculated. Among all the simulated scenarios, those who used the FTAI are those that presented a higher profit in almost all cases. The scenario using conventional artificial insemination (AI) obtained intermediate income, but also intermediate costs. The scenarios that used IVF generally presented higher cost of production and produced smaller numbers of calves. The scenario that used the crossbreeding showed positive economic results, but it registered the lowest genetic gain calculated, due to the smaller quantity of Nellore females produced. Therefore, considering the sale of animals at weaning, the scenario with the use of conventional artificial insemination (AI) is the most appropriate, since it combines intermediate economic results with intermediate rates of genetic gain. In order to commercialize the animals at slaughter, the FTAI (Nellore) is the most appropriate scenario, since it produces the highest observed profit (5.47 at/ha) (ha = hectare) and provides intermediate values of genetic gain (10.60% and 9.70% for males and females, respectively)
Descrição
Palavras-chave
biotecnologia, genética, lucratividade, Nelore, reprodução, biotechnology, genetics, profitability, Nellore, reproduction