Indução do estro em cutias (Dasyprocta leporina) utilizando-se protocolos à base de prostaglandina isolada ou em associação com análogo de GnRH

Abstract

RESUMO Comparou-se a eficiência de protocolos para indução de estro em cutias. Em cinco fêmeas, foram administradas duas doses de cloprostenol (5µg) com intervalo de nove dias, via intraperitoneal; em outras cinco, administraram-se 30µg de análogo do hormônio liberador de gonadotrofinas (GnRH), via intravulvar, seguidos de 5µg de cloprostenol, via intraperitoneal, após sete dias e, após mais dois dias, nova dose do análogo de GnRH. A cada três dias, a ciclicidade reprodutiva dos animais foi monitorada, por meio de coleta de sangue, para dosagem hormonal, ultrassonografia ovariana e citologia vaginal. Duas das fêmeas que receberam apenas prostaglandina, as quais estavam em fase luteal no início do tratamento, manifestaram o estro aos três e seis dias após a segunda administração da droga. Já nas fêmeas que receberam a prostaglandina associada ao análogo do GnRH, duas que originalmente estavam em fase luteal apresentaram estro aos quatro dias após o tratamento, e uma outra apenas após 10 dias. Não foram evidenciadas diferenças estatísticas quanto à eficiência dos tratamentos (P>0,05). Conclui-se que, de acordo com os protocolos utilizados, o uso da prostaglandina isolada ou em associação com análogo do GnRH para a indução do estro em cutias D. leporina apresenta eficiência limitada às fêmeas que estejam em fase luteal por ocasião do início do tratamento.

Ovum pick‐up and in vitro maturation in spotted paca (Cuniculus paca—Linnaeus, 1766)

“…In small rodentia, cloprostenol administered in higher dosis is efficient mainly if combined with progesterone, reaching up to 100% the response in oestrous synchronization and ovulation (Pallares & Gonzalez‐Bulnes, ). However, these results were not achieved in guinea pig (Grégoire et al, ) or agouti, showing limitations in oestrous induction (Peixoto et al, ). In addition, research has shown that the administered dose of this hormone may affect oestrous synchronization efficiency (Wei et al, ).…”

Reproduction in agouti (Dasyprocta spp.): A review of reproductive physiology for developing assisted reproductive techniques

“…Using only cloprostenol, estrus induction was verified in only 40% of females that manifested estrus signs and presented estrogen peak at 3 and 6 days after drug administration. However, combination therapy with both the hormones yielded estrus induction in 60% of animals, but 40% of the animals manifested estrus at day 4 and 20% at day 10 day after drug administration (Peixoto et al, 2018). Although these protocols promoted estrus induction, the authors do not suggest this method as an effective means to achieve synchronization of estrus induction in D. leporina.…”

Reproductive Technologies Used in Female Neo-Tropical Hystricomorphic Rodents

“…Blood collection for hormonal analysis (serum estradiol and progesterone) could also aid in monitoring the estrous cycle [ 50 ]. This was performed using a 1 mL syringe to obtain blood via the cephalic or saphenous vein, which was placed in glass tubes and centrifuged in preparation for analysis via amplified electrochemiluminescence.…”

“…This was performed using a 1 mL syringe to obtain blood via the cephalic or saphenous vein, which was placed in glass tubes and centrifuged in preparation for analysis via amplified electrochemiluminescence. The animals that showed external signs of estrus had corresponding increases in their estrogen levels (22.4 pg/mL and 17.5 pg/mL) and low progesterone levels (3.5 ± 0.2 ng/mL) under the cloprostenol only method of estrus induction [ 50 ]. When cloprostenol was used in combination with a gonadotropin releasing hormone (GnRH) analogue, those that had external signs of estrus had corresponding increases in their estrogen levels (12.3 pg/mL, 8.5 pg/mL and 8.3 pg/mL) and low progesterone levels (2.5 ng/mL and 2.3 ng/mL) [ 50 ].…”

“…The animals that showed external signs of estrus had corresponding increases in their estrogen levels (22.4 pg/mL and 17.5 pg/mL) and low progesterone levels (3.5 ± 0.2 ng/mL) under the cloprostenol only method of estrus induction [ 50 ]. When cloprostenol was used in combination with a gonadotropin releasing hormone (GnRH) analogue, those that had external signs of estrus had corresponding increases in their estrogen levels (12.3 pg/mL, 8.5 pg/mL and 8.3 pg/mL) and low progesterone levels (2.5 ng/mL and 2.3 ng/mL) [ 50 ]. Two peak periods of 17β-estradiol were also observed: one during metestrus and the other during proestrus [ 51 , 52 ].…”