Effect of the administration of alfaprostol 3 or 6 days after ovulation in jennies: ultrasonographic characteristic of corpora lutea and serum progesterone concentration

The Kisspeptin analogue C6 induces ovulation in jennies

“…In our study, the ultrasonographic characteristics (CSA, VA, and IV) of the corpus luteum obtained after C6-induced ovulation were similar to those obtained with buserelin or after natural ovulation. As has been previously reported for jennies, a positive correlation was found between corpora lutea CSA, VA but not IV with serum progesterone concentration [47]. Plasma progesterone concentrations were also similar between treatments.…”

Key Aspects of Donkey and Mule Reproduction

“…Clinical work in practice appears to contradict these findings. In addition, in a preliminary study, 1 out of 6 jennies responded to alphaprostol administration three days post-ovulation 87 . It is worth noting that these studies involved small numbers of jennies and that different types of PGF2α were used.…”

“…While ovarian structures (i.e., stroma, antral follicles, corpus luteum, corpus hemorrhagicum, and regressing corpus luteum) are similar in equids, the donkey corpus luteum often has a horizontal hyperechoic band or circular spot 22,41,42 . In some unusual cases, a central hypoechoic lacuna can also be seen 22 .…”

“…In some unusual cases, a central hypoechoic lacuna can also be seen 22 . During spontaneous and induced luteolysis, there is a transient increase in the blood flow to the corpus luteum which is associated with a concomitant reduction in progesterone concentrations 41,42 .…”

Studies on the Use of Prostaglandin F2α and Gonadotropin-Releasing Hormone Analogs for Timed Artificial Insemination in Jennies

“…PGF2α administration is commonly used to induce luteolysis and to shorten estrus cycle [43]. A recent manuscript reported that PGF2α is able to induce a complete luteolysis from day 6 after ovulation [44] and not from day 3 [45]: the presence of a functional CL susceptible to luteolysis was confirmed as to be a prerequisite for estrus synchronization with PGF2α. The results of the present manuscript, although based on a small number of animals and on a restrictive definition of positive response to the treatment, confirm the efficacy of PGF2α and GnRH analogue for estrus synchronization in jennies.…”