Submission Number: REB-4-22-20

Abstract Number: 154

EFFECT OF VITAMINS DURING MATURATION ON SUBSEQUENT DEVELOPMENTAL CAPACITY OF CAPRINE OOCYTES.

Charles L Bormann, E Moige Ongeri and Rebecca L Krisher*

Department of Animal Sciences, Purdue University, West Lafayette, IN, USA ¹

Abstract:
Very few caprine zygotes resulting from in vitro maturation (IVM) and in vitro fertilization (IVF) develop into blastocysts. Only a small proportion of goat oocytes selected for IVM can successfully complete cytoplasmic maturation and support embryonic development. To produce goat blastocysts more efficiently in vitro, it is necessary to accurately identify factors required during oocyte maturation. The objective of this study was to determine the role of vitamins during in vitro maturation of caprine oocytes in semi-defined medium on subsequent developmental capacity in vitro. Cumulus-oocyte complexes (COCs) collected from a local abattoir were matured in 50 l drops of synthetic oviductal fluid (SOF) medium supplemented with crystallized BSA (8 mg/ml), LH (0.01 unit/ml), FSH (0.01unit/ml), EGF (50 ng/ml), and PSA (100 units/ml penicillin, 100 g/ml streptomycin, 0.25 ng/ml amphotericin) in the presence or absence of MEM vitamins (1X) for 24h. The COCs were co-incubated with frozen-thawed sperm in Brackett and Oliphant medium for 18-22h. Embryos were cultured in 50 l drops of G1.2 medium for 72h followed by culture in G2.2 medium for an additional 72h (both supplemented with 8 mg/ml crystallized BSA). Blastocyst development was evaluated on d8 post-maturation (d6 of culture) and cell numbers counted by Hoechst staining. There was no significant difference in blastocyst development between the two treatment groups [15.4 1.4 % vitamins (n= 117), 12.6 1.2% controls (n=119)]. Similarly, there was no statistical difference in blastocyst mean cell numbers between vitamin treated and control groups (118.8 13.3, n=14; 113.5 11.9, n=19, respectively). These results suggest that supplementation of vitamins in semi-defined maturation medium does not confer an obvious advantage in subsequent development or quality of blastocysts. However, goat oocytes can be successfully matured in vitro in semi-defined medium, resulting in developmentally competent oocytes. .

Keywords: caprine, oocyte, vitamins

This abstract is being presented at: 8:00 AM in session:
Oocyte Development