LETHAL WHITE EYE SYNDROME IN PAINT HORSES: REPRODUCTIVE IMPACTS, GENETIC AND ZOOTECHNICAL ASPECTS
DOI:
https://doi.org/10.56238/levv16n53-006Keywords:
Paint Horse, EDNRB, Overo Lethal White Syndrome, Equine Genetics, Reproductive ManagementAbstract
The American Paint Horse stands out for its characteristic coat and versatility, but selective breeding for the frame overo coat pattern has resulted in Overo Lethal White Syndrome (OLWS), caused by a mutation in the Endothelin Receptor Type B (EDNRB) gene. While heterozygotes exhibit the typical overo frame phenotype and remain clinically healthy, homozygotes develop congenital intestinal aganglionosis, with severe colic and neonatal death, and have a completely white coat. The objective was to integrate historical, genetic, clinical, and ethical aspects of OLWS, highlighting scientific advances, challenges, and future perspectives. The analysis highlighted the molecular characterization of the mutation in the EDNRB gene, the validation of diagnostic methods such as PCR and HRM, as well as the economic and ethical implications of reproductive management in Paint Horse. The results indicate that, despite the extensive scientific knowledge available and the accessibility of genetic testing, cases of OLWS still occur in different countries. This persistence, even in the context of accessible and low-cost testing, reinforces the need for greater integration between science, animal welfare, and sustainability.
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