MELHORAMENTO GENÉTICO: ESTRATÉGIA PARA BOVINOS LEITEIROS MAIS RESISTENTES AO CARRAPATO-DO-BOI (Rhicephalus boophilus microplus)

Abstract

Dairy farming is an economically significant activity, generating income for producers of various scales. Despite its high productivity, it faces major challenges, such as the presence of ectoparasites, particularly the tick Rhipicephalus microplus, which causes substantial losses to the sector by contributing to disease development and reduced milk production. In this context, genetic improvement has proven to be an effective alternative for selecting animals with greater resistance to ticks. This study aimed to analyze scientific data associating genetic improvement with resistance to Rhipicephalus microplus. Research indicates that cattle with a higher proportion of European genetics (such as 3/4, 7/8, and 15/16 European × Zebu) tend to be more susceptible to the parasite, whereas those with greater Zebu influence (such as 5/8, 1/2, and 1/4 European × Zebu) exhibit higher resistance. Therefore, genetic improvement presents itself as a viable strategy to enhance dairy cattle resistance to Rhipicephalus microplus, one of the main health challenges in dairy farming. Crossbreeding between European and Zebu breeds allows for the combination of Zebu breeds' resilience and tick resistance with the high milk productivity of European breeds, in addition to enabling improvements in milk quality, such as A2 milk production and herd longevity.