Premium
Effect of eCG Superstimulation and Buserelin on Cumulus–Oocyte Complexes Recovery and Maturation in Llamas ( Lama glama )
Author(s) -
Trasorras VL,
Chaves MG,
Miragaya MH,
Pinto M,
Rutter B,
Flores M,
Agüero A
Publication year - 2009
Publication title -
reproduction in domestic animals
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.546
H-Index - 66
eISSN - 1439-0531
pISSN - 0936-6768
DOI - 10.1111/j.1439-0531.2007.00972.x
Subject(s) - buserelin , follicular phase , equine chorionic gonadotropin , medicine , endocrinology , follicle , oocyte , ovulation , biology , hormone , agonist , embryo , receptor , microbiology and biotechnology
Contents The aim of the present study was two fold. Experiment I: evaluate the effect of buserelin on llama’s oocyte maturation after exogenous follicular activity suppression, followed by ovarian superstimulation with different doses of equine chorionic gonadotropin (eCG). Experiment II: compare the number of follicles aspirated and the number of cumulus–oocyte complexes (COCs) recovered according to different doses of eCG followed by buserelin. Experiment I consisted in a control group (without buserelin) and a treatment group (with buserelin), both subdivided according to eCG dose administered: A: 500 IU; B: 1000 IU; C: 1500 IU. The treatment group received a single i.v. dose of 8 μg of buserelin when two or more dominant follicles were found at ultrasound evaluation and 20 h later were subjected to surgery. In group A, 83% of the llamas did not respond to superstimulation. In groups B and C differences were observed between the control and the treatment groups for the degree of COCs maturation (p < 0.05). In experiment II animals were divided into two groups according to the eCG dose administered: 1000 and 1500 IU. Twenty hours before surgery females received a single i.v. dose of 8 μg of buserelin. Average number of follicles aspirated and COCs recovered was higher (p < 0.05) with the administration of 1500 IU of eCG. A larger number of expanded COCs were obtained from follicles ≥7 mm in diameter. We conclude that buserelin aids the recovery of a larger number of expanded COCs. Administration of 1500 IU of eCG produces a higher number of follicles for aspiration and number of COCs recovered.