The relationship between the high embryonic mortality in swine and the heterogeneity of embryos of the same generation in RNA and SH-group content
Kvasnyts'kyĭ, O.V.; Martynenko, N.A.
Fiziolohichnyi Zhurnal 21(5): 642-648
1975
ISSN/ISBN: 0015-3311 PMID: 1240806 Document Number: 91858
The contents of RNA and SH-groups in pig embryos at the noncleavage stage and at the stage of 2-6-blastomeres were investigated by cytospectrophotometry. Variability of embryos of the same generation was high. A strong correlation between the percentage of embryonic viability (in the sow) and an average embryonic RNA content was noted; r = 0.764 for the absolute quantity of RNA, and r = 0.732 for the concentration (P > 0.98). Apparently these embryos are biologically defective, and they are lost if their RNA content is less than 500 pg. This assumption is based on the fact that embryos with the morphological characters of degeneration generally had RNA contents of less than 450 pg. The period of cleavage is critical for the developing embryos. A decrease in the content of SH-groups in zygotes during cleavage confirms this assumption.