Effect of pre‐treatment with deslorelin on the ovarian response of ewes superovulated with FSH

• Published in: Reproduction in domestic animals 2024-08, Vol.59 (8), p.e14688-n/a
• Main Authors: Garcia, Rodrigo, Filho, Rogério A. Almeida, Sitó‐Silva, Luan, Denadai, Renan, Codognoto, Viviane, Salgado, Letícia, Brochine, Suzane, Oba, Eunice
• Format: Article
• Language: English
• Subjects: Acetic acid; Animals; Cloprostenol - administration & dosage; Cloprostenol - pharmacology; Corpus luteum; Developmental stages; Embryo transfer; Embryo Transfer - veterinary; Embryos; Female; Fertility; Follicle Stimulating Hormone - administration & dosage; Follicle Stimulating Hormone - pharmacology; Follicle-stimulating hormone; Follicles; follicular dynamics; GnRH analogue; Gonadotropin-releasing hormone; Gonadotropin-Releasing Hormone - administration & dosage; Gonadotropin-Releasing Hormone - pharmacology; Intervals; Mating; Medroxyprogesterone acetate; Medroxyprogesterone Acetate - administration & dosage; Medroxyprogesterone Acetate - pharmacology; Ovarian Follicle - drug effects; Ovaries; Ovary - drug effects; Ovulation; Population studies; Pregnancy; Progesterone; Sheep - physiology; Sheep, Domestic; Superovulation - drug effects; Synchronism; Synchronization; Triptorelin Pamoate - administration & dosage; Triptorelin Pamoate - analogs & derivatives; Triptorelin Pamoate - pharmacology
• ISSN: 0936-6768; 1439-0531; 1439-0531
• DOI: 10.1111/rda.14688

This study evaluated the use of the GnRH agonist hormone, deslorelin, to control the follicular population before initiating multiple ovulation and embryo transfer (MOET) treatment. Twenty‐four cross‐bred Santa Inês ewes, aged between 2 and 4 years, were randomly assigned to either a control group (n = 11) or a treated group (n = 13). All ewes received an intravaginal device containing 60 mg of medroxyprogesterone acetate on day 0, and a new device on day 7, which remained in place until day 14. Additionally, the ewes were administered 125 μg of cloprostenol on day 7. The superovulatory treatment involved administering 200 mg of pFSH, divided into eight decreasing doses at 12‐h intervals starting on day 12. On day 14, 300 IU of eCG was administered. In the deslorelin group, three doses of 100 μg of deslorelin were administered starting on day 3 after the insertion of the vaginal device, with subsequent doses given at 72‐h and 144‐h intervals. Natural mating was performed 36 h after the removal of the progesterone implant using males with proven fertility. Embryo collection took place on the 6th day after mating, and the recovered structures were quantified and evaluated for quality and developmental stage. Transrectal ultrasonography was conducted on days 12, 16 and 21 to evaluate the ovaries, specifically to assess the ovarian follicular population and the presence of the corpus luteum. Ewes in the control group had higher embryo recovery rates (p