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

Abstract

RESUMO.-O objetivo deste estudo foi monitorar o ciclo estral em cutias (Dasyprocta leporina) criadas em cativeiro no semiárido brasileiro. Durante 70 dias, cinco cutias foram diariamente submetidas a citologia esfoliativa vaginal, e o monitoramento ultrassonográfico ovariano foi realizado a cada três dias. Um total de 8 ciclos estrais foi completamente monitorado, com duração de 28,2±0,7 dias, variando de 24 a 31 dias. Pela citologia esfoliativa vaginal, houve uma predominância de células superficiais nas fases de proestro e estro (P<0,05), seguida da predominância de células intermediárias no metaestro (P<0,05) e de células parabasais no diestro (P<0,05). Por ultrassonografia, não houve diferenças na morfologia ovariana durante as diferentes fases do ciclo estral (P>0,05). Os folículos foram identificados durante as fases estrogênicas (proestro e estro), com diâ-metro médio de 1±0,5mm. Em apenas 12,5% das fases luteais, corpos lúteos medindo 1,4±0,9mm foram identificados. Conclui-se que a associação da citologia vaginal e da ultrassonografia ovariana constitui uma alternativa viável para o monitoramento de ciclos estrais e identificação das fases estrogênicas em cutias da espécie Dasyprocta leporina. TERMOS DE INDEXAÇÃO:Dasyprocta leporina, roedores, colpocitologia, ecografia ovariana. INTRODUÇÃOAs cutias (Dasyprocta sp.) são roedores utilizadas frequentemente como fonte de alimento e extração de sua pele, couro e pelos por populações humanas (Lopes et al. 2004 The objective of the study was to monitor the estrous cycle in agoutis (Dasyprocta leporina) bred in captivity in Brazilian semiarid. During 70 days, five agoutis were daily subjected to vaginal exfoliative cytology, and the ovarian ultrasound monitoring was conducted every three days. A total of 8 estrous cycles were completely monitored, lasting 28.2±0.7 days, ranging from 24 to 31 days. By vaginal exfoliative cytology, there was predominance of superficial cells at proestrus and estrus phases (P<0.05), followed by the predominance of intermediate cells in the metestrus (P<0.05) and parabasal cells in diestrus (P<0.05). By ultrasound, there were no differences in ovarian morphology during the different phases of the estrous cycle (P>0.05). Follicles during the estrogenic phases (proestrus and estrus) were identified, with an average diameter of 1±0.5mm. In only 12.5% of luteal phases, corpora lutea measuring 1.4±0.9mm were identified. We conclude that the association of vaginal cytology and ovarian ultrasonography is a useful alternative for monitoring the estrous cycle and identifying the estrogenic phases in Dasyprocta leporina.INDEX TERMS: Dasyprocta leporina, rodents, colpocytology, ovarian echography.

Serological evaluation of ovarian steroids of red-rumped agouti (Dasyprocta leporina) during the estrous cycle phases

“…In other domestic farm species, knowledge of the durations of the diestrus phase and refractory period of the corpus luteum, have been critical in the design of estrus synchronization protocols. (Pursley et al, 1997;Noakes et al, 2009) Our results reinforce previous reports on the length of the estrous cycle by Guimarães et al (2011) andCampos et al (2015) where a non-seasonal polyestrous pattern was reported for captive agouti. In the present study, we also describe the average length of the four phases of the estrous cycle and E2 peaks which were consistently recorded for all eight animals in this study.…”

“…This is identical to the assumptions used in other studies (Guimarães et al, 1997;Marcondes et al, 2002). However, to ensure accuracy in future studies, ultrasonography should be performed trans-abdominally to confirm sudden disappearance of the dominant follicle(s) as described in the bitch (Groppetti et al, 2015) and the red-rumped agouti (Campos et al, 2015) P4 reached a peak concentration of 4.26 ng/ml in diestrus in captive female agouti. This value is different for a number of hystricomorphs species reported in the literature.…”

“…Campos et al used ultrasonography coupled with colpocytology and the assessment of external genitalia to monitor the estrous cycle of two red-rumped agouti (D. leporina) and reported a relatively long follicular phase based on changes in the dimension of the ovary and the protrusion of follicles on the surface of the ovary (Campos et al, 2015). Their results were similar to those described by Guimarães et al However; only proestrus and estrus were distinguished by Campos et al, but there is no mention of the duration of these phases.…”

“…in captivity (Guimarães et al, 2011). Females have been reported as polyestrous spontaneous ovulators demonstrating non-seasonal breeding, with an estrous cycle of 31 days (Roth-Kolar, 1957;Smythe, 1970;Weir, 1971;Meritt, 1983;Guimarães et al, 1997;Campos et al, 2015) and a period of sexual receptivity of approximately 24 h (Guimarães et al, 2011). Gestation length is 104 ± 1.3 days, with an average litter of two precocious young (Roth-Kolar, 1957;Guimarães et al, 1997;Langer, 2003;Brown-Uddenberg et al, 2004;Brito et al, 2010).…”

Understanding mammary activity in red-rumped agouti and implications for management and conservation of this Neotropical game species

“…The female agouti has eight mammae, two pairs in the thoracic region and two pairs in the abdominal region (Baas et al, 1976;Deem, 2012). It is a non-seasonal breeder (Baas et al, 1976;Campos et al, 2015;Guimarães et al, 2011;Singh et al, 2014) and under captive conditions, when receiving an abundance of food with a high plane of nutrition may produce larger litters (Singh and Garcia, 2015). Agoutis reach puberty at eight months and go through gestation for 104 to 120 days (Guimarães et al, 2011;Lopes et al, 2004;Weir, 1971) producing litters between one and six young (Brown-Uddenberg et al, 2004;Dollinger et al, 1999;Lopes et al, 2004;Singh and Garcia, 2015).…”