Highlighting factors contributing to pregnancy loss in beef cattle

Pregnancy loss in beef cattle remains a costly problem for producers, leading to diminished calf crop uniformity and reduced percentages of cows with a calf at the end of calving season. Although several tools exist to ascertain pregnancy status, the first 30 days of pregnancy encompasses the period with the greatest proportion of pregnancy losses and these losses often occur before traditional methods permit pregnancy determination. The ability to accurately predict pregnancy failure remains a major limitation. Blood-based assays detecting chemical changes in maternal circulation have provided insight into embryonic and fetal monitoring and are used to make predictions for pregnancy loss. Although there are certain unknown aspects to the etiology of pregnancy loss, there is growing body of work to identify physiological biomarkers within the maternal, paternal, and embryonic systems to clarify risk factors for pregnancy failure. This review highlights a few of the factors contributing to pregnancy loss and the rapidly evolving methods utilized to predict pregnancy failure. Further, this review highlights a few of the changes to parental physiology after exposure to various environmental factors, the consequences on the physiology of pregnancy and the likelihood of pregnancy success.