Many managed captive animal populations experience low rates of reproductive success. Since AZA institutions participate in cooperative breeding programs through Species Survival Plan programs, logistical challenges may prevent recommended pairs from being placed together for breeding. In addition, reasons for reproductive failure may include, for example, pair incompatibility, improper light cycles, insufficient flock size, inadequate nutrition or over-conditioning, and physiological infertility. The RMC’s role is to identify patterns of reproductive failure across a population or across taxonomic groups and to develop tools that can be used to increase reproductive success rates. In contrast, the Reproduction and Endocrine Scientific Advisory Group addresses more specific problems, such as assisting institutions in evaluating reproductive failure in individual animals or pairs.
Recent and current RMC initiatives related to evaluating large-scale threats to captive population sustainability include:
- Partnering with the Reproductive Health Surveillance Program for research on the relationship between reproductive pathology and infertility
- Organizing an Infertility Workshop focused on approaches to diagnosis, treatment, and preventing infertility
- Ongoing research into the “use it or lose it” phenomenon, which has shown that simply separating females from males can contribute to female infertility (Asa et al. 2014; Penfold et al., 2014)
- Pioneering a new method of reproductive management called Lifetime Reproductive Planning designed to establish and maintain female fertility
- Developing tools that can be used by the AZA zoo community to evaluate fertility in males and females
Reproductive Enhancement Contacts and Tools
AZA Scientific Advisory Groups and Committees: The RMC integrates and coordinates with the AZA SAGs and Committees that are most relevant to addressing the causes of reproductive failure. More information about this effort, a list of SAGs and Committees involved in this consortium, and links to those groups can be found here.
Reproduction Advisors: Many TAGs and SSPs have Reproduction Advisors who can provide expert advice on topics related to reproduction. The Reproduction and Endocrine SAG can assist you with identifying the appropriate Reproduction Advisor for your species.
Transcervical Endometrial Biopsy: This tool, developed by our colleague, Dr. Bruce Christensen at the University of California-Davis, can be useful in detecting early-stage pathological changes in the uterine endometrium. Endometrial hyperplasia is a condition that can impair fertility and is a precursor condition for pyometra, a potentially fatal uterine infection, in some taxa. Advanced cystic endometrial hyperplasia (CEH) can be visualized on ultrasound, but at that point, the female’s fertility is likely greatly diminished or permanently compromised. Transcervical endometrial biopsy offers the possibility of diagnosing EH before it advances to the cystic stage, so that therapies can be implemented sooner. Dr. Christensen has trained a network of veterinarians across the U.S. to perform the biopsies and the RMC can coordinate the procedure for your institution. To date, biopsies have been performed in large canids and felids (African painted dogs, African lions, red and Mexican wolves). We are currently exploring the possibility of using this technique in additional taxonomic groups, such as equids and otters. Please contact us for more information, firstname.lastname@example.org
Infertility Checklist and Decision Tree: In 2014, our Infertility Workshop resulted in two diagnostic reference tools designed to be used as a guide for identifying potential causes of reproductive failure, a decision tree for diagnosing infertility in ungulates and a clinical history checklist for carnivore infertility. In 2021, we worked with the European Association of Zoo & Aquaria’s Reproductive Management Group (EAZA RMG) and the Reproduction & Endocrinology Scientific Advisory Group (RESAG) to create a more standardized and comprehensive Reproductive Checklist to Assess Fertility. This exhaustive checklist is intended to foster dialog between keepers, curators, veterinarians, and consulting reproductive specialists when trying to diagnose fertility-related issues.