Laparoscopic ovum collection in sheep: Gross and microscopic evaluation of the ovary and influence on ooctye production

Abstract

Gross and microscopic evaluations of the ovaries of sheep subjected to successive ovum collection were performed with the objective of identifying if there was interference in oocyte production and morphology of gonads. Gross evaluation of the internal genital tract was also performed. Eighteen ewes of the Santa Ines breed were randomly distributed into three experimental groups of six animals each: G0, G1 and G9 with no, one and nine repetitions, respectively. Estrous synchronization was achieved with a short protocol using MAP followed by single dose stimulation with 80 mg of FSHp and 300 Ill of eCG (IM). Laparoscopic ovum pick-up was performed 36 h later, with 7-day intervals. The number of visualized follicles, aspirated follicles and oocytes recovery was recorded. After the last intervention, ovariectomy was performed for evaluation of gross and microscopical appearance and existence of lesions caused by follicular puncture, which were classified as absent (0), mild (1), moderate (2) and severe (3). The number of visualized follicles, aspirated follicles and oocytes recovery were 13.2 +/- 2.0, 11.3 +/- 3.0 and 5.8 +/- 2.3, respectively, with a recovery rate of 51.7%. No statistical difference was found between the nine sessions (P > 0.05). Nine sessions of superovulation and ovum collection procedures did not cause ovarian lesions and did not interfere with the production of follicles in ewes of the Santa Ines breed. (C) 2011 Elsevier B.V. All rights reserved.