Integrating physiological concepts with economic and management information to realize improvements in reproductive efficiency in Brazilian dairy herds

Abstract

This proposal focuses on improving reproduction in commercial Brazilian dairy farms. Two specific objectives will be completed during a one-year project. The first specific objective is to evaluate differences in reproductive efficiency using three specific reproductive management programs in commercial Brazilian dairy farms. Brazilian dairy farms have many options for managing reproduction. Two of the most utilized are artificial insemination (AI) after detection of estrus or timed AI after synchronized ovulation. In the U.S.A., timed AI programs have been extensively researched and are based primarily on GnRH-based protocols. In Brazil, simpler and more cost-effective protocols, termed estradiol-based protocols, have been developed. These perform better under Brazilian conditions than the GnRH-based protocols. This research will validly evaluate 2 main ideas related to reproductive management programs. The first is whether increasing progesterone during an estradiol-based timed AI protocol will increase fertility. This strategy has been the most productive for increasing fertility in GnRH-based protocols in the U.S.A. Secondly, the research will compare the reproductive efficiency and economics of programs that use exclusively timed AI protocols compared to programs that utilize primarily detection of estrus. Completion of this first specific objective will provide important research information on the biology and practical aspects of applying different reproductive management programs in commercial Brazilian dairy farms. The second specific objective is a teaching and training objective. Training courses will be organized to train young scientists, practicing veterinarians, and dairy producers in the science and art of designing and implementing effective reproductive management programs. The physiological, economic, and management aspects of research from the first specific objective and other research will be integrated into a series of modules that will provide appropriate and timely training for these groups. (AU)