Puberty and oestral cycle length in captive female jaguars Panthera onca

Testicular tissue cryopreservation and transplantation as a strategy for feline conservation: a review of research advances

As we humans continue our detrimental activities on the planet, the biodiversity loss is now seen as a big threat to entire ecosystem in which we all live. This issue becomes even more critical as we see a rapid increase in the number of animal species being listed as endangered, and a far greater rate of species extinction. We all know that felines play a crucial part in our ecosystems, it is therefore safe to argue that their conservation could play an important role in minimizing the biodiversity loss. Advanced reproductive biotechnologies including testicular tissue cryopreservation and transplantation are considered as effective tools for the conservation of animal species. As we have seen with the Giant Panda, these biotechnologies could offer new possibilities for the conservation of other endangered species including felines. Although previously a few wild feline spp. were conserved by this method, little is known about the factors influencing the efficiency of these methods. Therefore, if we are to maximize the conservation efforts, further optimization of these biotechnologies is required to achieve better conservation results. In this article, we present an overview of testicular tissue of felines and the factors influencing testicular tissue cryopreservation and testicular graft recovery in felines.

Reproductive evaluation of Luisa, the last jaguar of the Caatinga

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.

Cycle length flexibility: is the duration of sexual receptivity associated with changes in social pressures?

Research in social mammals has revealed the complexity of strategies females use in response to female-female reproductive competition and sexual conflict. One point at which competition and conflict manifests acutely is during sexual receptivity, indicated by swellings in some primates. Whether females can adjust their sexual receptivity from cycle to cycle to decrease reproductive competition and sexual conflict in response to social pressures has not been tested. As a first step, this study explores whether sexual receptivity duration is predicted by social pressures in wild female chacma baboons (Papio ursinus). Given that female baboons face intense reproductive competition and sexual coercion, we predicted that: females could shorten the duration of their sexual receptive period to reduce female-female aggression and male coercion or increase it to access multiple or their preferred male(s). We quantified 157 ovulatory cycles from 46 wild females living in central Namibia recorded over 15 years. We found no support for our hypothesis; however, our analyses revealed a negative correlation between maximal-swelling duration and group size, a proxy of within-group competition. This study provides further evidence that swelling is costly as well as a testable framework for future investigations of 'cycle length manipulation'.

Cryptorchidism in free-living jaguar (Panthera onca): first case report

Cryptorchidism is a genital alteration wherein one or both testicles fail to descend into the scrotum and has multifactorial causes. A free-range adult male was captured twice in the Pantanal of Nhecolândia to put a GPS collar and semen collection. Pharmacological semen collection, andrological examination and semen analysis were performed. At the first capture and during the andrological examination only the left testis was found, and the male qualified as cryptorchid. The penis had no penile spines at either procedure. The semen volume obtained at first and second capture was 435 and 160 μL, respectively, with a concentration of 618 and 100 x 10⁶ sperm/mL, progressive motility of ~ 5% and ~ 1% and total morphological sperm abnormalities of 74% and 86%. The male was monitored by a GPS collar, but the signal was lost, making it difficult to re-captures and perform new seminal and ultrasound evaluations to discard monorchidism - exceedingly rare in felids. Genetic studies to assess the individual's homozygosity are necessary to verify whether cryptorchidism in this individual has a genetic factor.