Embryo recovery rate in Santa Inês ewes subjected to successive superovulatory treatments with pFSH

Effect of age of donor on embryo production in Morada Nova (white variety) ewes participating in a conservation programme in Brazil

“…Data concerning superovulatory response showed that the refractoriness of ovary (< 5 ovulations) of Morada Nova ewes (25%) is in agreement with previous studies that reported that 20% of treated females did not respond to superovulation treatment (Brebion et al, 1992;D'Alessandro et al, 1996;Cordeiro et al, 2003). However, the ewes that responded to superovulatory treatment with pFSH presented a higher ovulation rate than rates reported for Bharat Merino (5.6 ± 2.3) and Rambouillet (5.9 ± 1.9) ewes maintained under semi-arid conditions Gulyani, 1996, 1999).…”

“…However, the response of embryo donors of different sheep breeds is extremely variable and several factors such as donor age (Alabart et al, 2003) appear to be responsible for this variability. In addition, information about embryo production of local sheep breeds raised in north-eastern Brazil is scarce (Cordeiro et al, 2003).…”

A study on superovulation using FSH and eCG in Awassi ewes

“…It is that the observed differences in superovulatory response were attributed to hormonal treatment differences in ovarian response. Cordeiro et al (2003) obtained similar results. Higher superovulatory response was obtained during the breeding season using FSH and eCG treatments.…”

Does supplemental LH changes rate and time to ovulation and embryo yield in Santa Ines ewes treated for superovulation with FSH plus eCG?

“…Morphological evaluation was performed under a stereomicroscope (40X magnification) following the IETS recommendations. The SOV response was classified using three scores (adapted from CORDEIRO et al, 2003) as follows: (0) ewes with 4 or less CL, characterizing a lack of response to the SOV treatment; (1) ewes with 5 to 10CL, characterizing intermediate SOV response; and (2) ewes with 11 or more CL, characterizing high response to the SOV treatment. According to the time to ovulation, the ewes were classified as: (i) ewes that ovulated before 42h, (ii) those that ovulated between 42 and 48h, and (iii) ewes that ovulated 48h after CIDR removal.…”