A comparison between non-surgical and laparoscopic embryo collection and transfer in goats

Abstract

Traditional embryo collection and transfer utilizing laparotomy in goats frequently results in adhesions that can reduce the overall reproductive performance of the animal. The objectives of this study were to develop and compare the use and efficiency of less invasive techniques, laparoscopic and non-surgical, for embryo collection and transfer in goats. These techniques were evaluated by comparing the collection and pregnancy rates achieved during this project. Several parameters were recorded during these procedures; 1. superovulatory response, 2. morphological characteristics of the corpus luteum (CL) and its effect on collection and pregnancy rates, 3. length of time for ovarian observation, 4. ease of collection and transfer and 5. length of time for embryo collection and transfer. Spanish cross donor does (n=75) were subjected to a synchronization and superovulatory regimen. Donor animals exhibiting signs of estrus (n=59) were subjected to a laparoscopic ovarian evaluation. Of these, 13 (22%) presented early regressing CL (ERCL). Of 43 synchronized recipients examined laparoscopically, 5 (11.6%) presented ERCL. Those animals that exhibited ERCL were not used for embryo collection or transfer. The time required to perform laparoscopic ovarian evaluation increased with the increasing number of ovulations (range I min 58 see to 12 min 34 see). Donor does demonstrated a mean L+SE) of 11.8+1.7 ovulations. Mean L+SE) percent embryo recovery rates of 46.9+8.0 and 60.4+7.6 were achieved using the non-surgical and laparoscopic techniques, respectively. The embryo/ova recovery rates as a function of ovulation rate were demonstrated to be higher for the laparoscopic technique when the ovulation rate was greater than 16. Both collection techniques required approximately 45 minutes to perform. The pregnancy rates (42.1% for both) achieved with both embryo transfer techniques demonstrated to be identical. The presence of an antral follicle and/or a CA concomitant with a CL did not statistically influence the mean pregnancy rate. The average time required to perform embryo transfers by laparoscopy was shorter than the time required for non-surgical transfer (4:00 vs.. 9:54 min). The results of this research indicate that laparoscopic embryo collection resulted in a significantly higher embryo recovery rate than non-surgical embryo collection, however the rate of embryo recovery for individual animals ranged from 0-I 00% utilizing both techniques.