The aim of this study was to clarify the effects of linoleic acid (LA)/alpha-linolenic acid (ALA) ratio on oocyte maturation and fertilization. Prepubertal sheep ovaries were sliced, then cumulus-oocyte complexes were matured in a media based on TCM-199 supplemented with FSH, LH, epidermal growth factor, BSA fraction V, cysteamine, glutamine, and sodium pyruvate for 24 h in different ratios of LA/ALA (0, 1 : 1, 2 : 1, 4 : 1, and 10 : 1). After maturation, 169 oocytes stained for maturation rate. In the second experiment, 176 presumptive zygotes from 227 fertilized oocytes were stained for fertilization rate. In the third experiment, 570 oocytes were used for embryo development. The generalized linear model was used for analysis. The results showed that LA/ALA at the ratios of 1 : 1, 2 : 1, and 4 : 1 significantly (P < 0.05) improved the MII percentages and the 10 : 1 ratio was detrimental. Fertilization rate was not significant between treatments, but the two pro-nuclei percentage was significantly increased for the ratios of 1 : 1, 2 : 1, and 4 : 1 (P < 0.05). Cleavage rate for the ratio of 2 : 1 and 4 : 1 was significantly higher (P < 0.05). The ratio of 10 : 1 was detrimental for embryo development, and none of the cleaved embryos reached the blastocyst rate. In conclusion, the ratio of 10 : 1 LA/ALA was detrimental and resulted in degenerated oocytes and subsequently for prepubertal sheep embryos, whereas lower ratios of LA/ALA were beneficial for oocyte competition and fertilisation.
Alpha-linolenic acid and linoleic acid differentially regulate the skeletal muscle secretome of obese Zucker rats