AI systems today sell twice as many straws per calf born as they did in the 1970s, in spite of all the advances in technologies and near-universal adoption of “production medicine” approaches by veterinarians. For many dairymen the cost of each cow pregnancy has grown to several hundred dollars (ultrasounding, pre synch shots, Ov Synch, multiple services per cow, sexed semen on heifers) as traditional fertility management (breeding on observed natural heats) has gone out the window for these operations.
What role did decades of ignoring genetic fertility play in this development? We think the answer is simple—it is Darwinian to assume that “genes not exercised in the current environment will be lost to future generations”. If we ignore fertility genes, they do not stay the same—selection for anything else (especially if negatively correlated to fertility) will result in a declining “genetic base’ for that gene expression.
Want to improve the fertility in your herd by genetics? Use the tools already available; health and fitness traits, maternal pedigree screening for longevity, physical balancing of matings from the “aAa” breeding guide. Your progress will be measurable.