Estrus cycle monitoring of captive collared peccaries (Pecari tajacu) in semiarid conditions

Abstract

RESUMO.-[Monitoramento de ciclo estral em catetos (Pecari tajacu) criados em cativeiro em condições semiáridas.] Os catetos (Peccary tajacu) estão entre as espécies mais caçadas na América Latina devido a apreciação de seu couro e carne. No intuito de otimizar o manejo produtivo de catetos nascidos em cativeiro sob condições semiáridas, o objetivo foi descrever e correlacionar as modificações verificadas no padrão ultrassonográfico ovariano, o perfil hormonal, a aparência vulvar, e a citologia vaginal durante o ciclo estral nesta espécie. Durante 45 dias, fêmeas (n=4) foram submetidas a coleta de sangue destinado a dosagem hormonal por meio de teste imuno-enzimático (EIA). Na mesma ocasião, foram conduzidas a avaliação da genitália externa, a ultrassonografia ovariana e a citologia vaginal. Os resultados são apresentados com média e desvio padrão De acordo com a dosagem hormonal, foram identificados seis ciclos estrais, com duração 21,0±5,7 dias, sendo em média 6 dias de fase estrogênica e 15 dias de fase proges- Collared peccaries (Peccary tajacu) are among the most hunted species in Latin America due the appreciation of their pelt and meat. In order to optimize breeding management of captive born collared peccaries in semiarid conditions, the objective was to describe and correlate the changes in the ovarian ultrasonographic pattern, hormonal profile, vulvar appearance, and vaginal cytology during the estrus cycle in this species. During 45 days, females (n=4) were subjected each three days to blood collection destined to hormonal dosage by enzyme immunoassay (EIA). In the same occasions, evaluation of external genitalia, ovarian ultrasonography and vaginal cytology were conducted. Results are presented as means and standard deviations. According to hormonal dosage, six estrous cycles were identified as lasting 21.0 ± 5.7 days, being on average 6 days for the estrogenic phase and 15 days for the progesterone phase. Estrogen presented mean peak values of 55.6 ± 20.5 pg/mL. During the luteal phase, the high values for progesterone were 35.3 ± 4.4 ng/mL. The presence of vaginal mucus, a reddish vaginal mucosa and the separation of the vulvar lips were verified in all animals during the estrogenic peak. Through ultrasonography, ovarian follicles measuring 0.2±0.1 cm were visualized during the estrogen peak. Corpora lutea presented hyperechoic regions measuring 0.4±0.2 cm identified during luteal phase. No significant differences (P>0.05) between proportions of vaginal epithelial cells were identified when comparing estrogenic and progesterone phases. In conclusion, female collared peccaries, captive born in semiarid conditions, have an estral cycle that lasts 21.0±5.7 days, with estrous signs characterized by vulvar lips edema and hyperemic vaginal mucosa, coinciding with developed follicles and high estrogen levels.

Estrous Synchronization in Captive Collared Peccaries (Pecari tajacu) using a Prostaglandin F2α Analog

“…Interestingly, the Animal 5 showed the lowest values for estrogen peak (14.5 pg/ml), but it was the one that established the most evident estrous signs, including the opening of the vulva lips. Also of note, the average values found for estrogen peak during synchronized estrous were lower than those described for a similar group of captive individuals during natural estrous, 55.6 pg/mL (Maia et al, 2014). Such differences could probably be associated with a variation among different individuals.…”

“…Once the luteal phase of the estrous cycle of peccaries usually lasts 15 days on average (Maia et al, 2014), a second prostaglandin administration is recommended in order to promote the lysis of corpora luteum that were not formed in first occasion. The second administration was conducted after nine days, enough time for the formation of a new corpora luteum in those females that were in follicular phase in the initial moment.…”

“…The female collared peccaries, captive born in semiarid conditions, present an estrous cycle that lasts 21.0 ± 5.7 days, with estrous signs characterized by vulvar lip edema and hyperemic vaginal mucosa, coinciding with developed follicles and high estrogen levels (Maia et al, 2014). No data regarding estrous control, however, is available for this species.…”

Morphology of the genital organs of the female red‐rumped agouti (Dasyprocta leporina, Linnaeus, 1758) during estrous cycle phases and in advanced pregnancy

“…Slices of 5–7 μm thickness were cut, mounted on slides, and stained with hematoxylin and eosin, Gomori's trichrome, Alcian‐Mallory, or periodic acid‐Schiff (PAS) and examined using a light microscope. Microscopic examination of the ovaries was important to confirm the estrous cycle phase, follicular development, and presence of corpora lutea (CL) (Maia et al, ; Moura et al, ; Santos et al, ). The thickness of the muscular layer of the uterine tube (infundibulum, isthmus, and ampulla) and the diameter and height of the epithelium of the uterus and vagina were measured using ImageJ1® software (Schneider, Rasband, & Eliceiri, ).…”

Monitoramento do ciclo estral de cutias (Dasyprocta leporina Lichtenstein, 1823) através de citologia esfoliativa vaginal e ultrassonografia

“…Nos últimos anos, o uso da ultrassonografia em tempo real tem despontado como uma importante ferramenta para o estudo da dinâmica ovariana durante o ciclo estral em inúmeros mamíferos (Maia et al 2014), possibilitando inclusive, a identificação do estro (Griffin & Ginther 1992). Em roedores silvestres, estudos relacionados à aplicação da técnica de ultrassonografia à reprodução são escassos.…”