Monitoring sexual steroids and cortisol at different stages of the ovarian cycle from two capuchin monkey species: use of non- or less invasive methods than blood sampling

Abstract

Endocrine monitoring of non-human primates (NHP) via faecal metabolites of steroid hormones appears as a useful non-invasive alternative to evaluate the reproductive status of free living NHP, as well as of those kept in captivity but of difficult handling. However, validation is needed with plasma values before its application in the field. The aim of the present study was to monitor the different phases of the menstrual cycle from the new world NHP Sapajus apella and S. libidinosus. For this, hormonal and faecal plasma levels of E 2 , P 4 and cortisol were assessed during different days of the menstrual cycle, together with colpocitology. The mean duration of the menstrual cycle according colpocitology was of 21.7 and 21.0 days for S. apella and S. libidinosus, respectively. These values were similar to those observed via plasma analysis, i.e. 22.7 and 20.3 days for S. apella and S. libidinosus, respectively. The day of plasmatic E 2 peak was set as Day -1 and the estimated day of ovulation was set as Day 0 and occurred two days earlier in S. libidinosus than in S. apella females. In both species, it was observed a delay in faecal E 2 peak of six days for S. apella and of 11 days for S. libidinosus when compared with the plasma peak. A maximum P 4 plasma concentration was observed in the middle of luteal phase in S. apella and in S. libidinosus, both at around day 5 . However, faecal P 4 peaks were detected at days 9 and 8 in S. apella and S. libidinosus , respectively. Mean plasma and faecal cortisol levels were variable during all ovulatory cycle of S. apella and S. libidinosus females. Although no exact correlation was observed between plasmatic and faecal profile of steroid hormone, faecal samples were able to indicate ovarian cycle phase, being important to assess the reproductive status of the females applying a non-invasive method.

Zika Virus Infection Damages the Testes in Pubertal Common Squirrel Monkeys (Saimiri collinsi)

“…Then, the diluted samples were homogenized overnight and subjected to centrifugation at 3000 rpm for 15 min. The supernatant was stored in microtubes, which were labeled with the animal and date and stored at −70° C until the evaluation of hormone levels [ 38 , 39 ]. Fecal testosterone levels (ng/mL) were measured by a chemiluminescence assay using the VITROS ® immunoassay system (VITROS ® ECiQ, Ortho Clinical Diagnostics, NJ, USA).…”

Follicular Atresia, Cell Proliferation, and Anti-Mullerian Hormone in Two Neotropical Primates (Aotus nancymae and Sapajus macrocephalus)

“…and Cebus spp.) [ 4 , 7 , 8 ]. There are behavioral differences between the primates, such as their mating systems.…”

Reproductive physiology with emphasis on endometrial cycles of woolly and uakari monkeys—A literature review

“…Regarding Neotropical nonhuman primates, research has traditionally been based only on systematic observations of social and reproductive behavior, which limits the acquisition of information related to morphophysiological aspects (Andrabi & Maxwell, 2007; Pukazhenthi & Wildt, 2004). Although studies on endocrinology and reproductive cycles are available, they are specifically focused on species raised in animal facilities and used as experimental models (Bakker et al, 2018; Fernandez‐Duque, 2012; Lima et al, 2019). However, the maintenance of wild species in captivity can produce important reproductive variations due to multiple factors, such as stress, availability of resources, territories, and the composition of social groups (Mayor et al, 2017).…”