Current Insights in the Repeat Breeder Cow Syndrome

Area of Science:

• Veterinary Science
• Animal Reproduction
• Bovine Medicine

Background:

• Repeat breeder cow (RBC) syndrome is a significant cause of infertility in cattle, characterized by repeated failure to conceive despite normal estrous cycles and absence of clinical signs.
• This condition has a substantial global incidence, leading to considerable economic losses in the livestock industry.
• Existing research indicates potential causes including hormonal imbalances, undetected oviductal or uterine abnormalities, and poor oocyte/embryo quality, with subclinical endometritis being a key factor.

Purpose of the Study:

• To review and synthesize existing literature on Repeat Breeder Cow (RBC) syndrome from 2000 to 2023.
• To consolidate current knowledge on the causes, risk factors, and potential mechanisms underlying RBC syndrome.
• To identify knowledge gaps and emphasize the need for advanced diagnostic tools and therapeutic strategies for bovine infertility.

Main Methods:

• Comprehensive literature review of studies on RBC syndrome published between 2000 and 2023.
• Inclusion of consolidated information up to the present date.
• Analysis of reported causes, risk factors, and emerging research on genetic and molecular factors.

Main Results:

• Hormonal imbalances, undetected reproductive tract defects, and compromised oocyte/embryo quality are frequently implicated in RBC syndrome.
• Subclinical endometritis is recognized as a significant contributing factor to recurrent infertility in cows.
• Recent research is investigating the role of specific genes, hormones, and proteins in the pathogenesis of RBC syndrome, alongside numerous identified risk factors.

Conclusions:

• The etiology of RBC syndrome is complex and multifactorial, with recurrence in certain animals remaining unexplained despite interventions.
• Further research is crucial to elucidate the underlying mechanisms, develop precise diagnostic methods, and establish effective treatments to restore fertility in affected cows.
• Addressing RBC syndrome is vital for improving farm profitability, necessitating a deeper understanding of its economic impact.