Reproductive evaluation of Luisa, the last jaguar of the Caatinga

Abstract

The in situ population of jaguars in the Caatinga is less than 250 individuals, subdivided into five subpopulations, and is classified as endangered regarding its risk of extinction. Luisa, a 15-year-old female weighing 36 kg, was the last known ex situ jaguar from this biome. Her reproductive evaluation is detailed in this manuscript. Luisa was subjected to both a clinical and laparoscopic evaluation of her reproductive system. After 45 days of reproductive investigation, she died unexpectedly, and skin fragments were taken to establish the postmortem fibroblast lineage. At the clinical evaluation, Luisa had small, undeveloped mammary gland and a small vulva, characteristic of a nulliparous female, with no mammary gland nodules, edema, or abnormal masses. By laparoscopy, normal-appearing bladder and bowel loops were observed, as were uterine horns with standard color, shape, and length with no striae. Ovaries and uterine horns seem free of fibrinous adhesions. Both ovaries showed a yellowish color, a fibrous consistency, a decreased size (atrophied), and no follicles, hemorrhagic corpus, corpus luteum, luteal scars, or other abnormal structures. We may assume that this jaguar female was infertile based on Luisa's mature age and the absence of birthing or ovarian activity signs. The harsh conditions of the Caatinga biome, which included low food availability and frequent conflicts with humans, may have impacted both the pregnancy and lactation of Luisa's mother and her development after birth.