Table 2. Effect of chloramphenicol on the second cleavage of mouse conceptuses.

stage	2-cell	3-cell	4∼8-cell	total
CP	65	26	36	127
vehicle	2	0	80	82

Late pronuclei stage zygotes (around E0.75) were cultured for 24 hours in presence of either 200 µg/mL of chloramphenicol (CP) or 1% of DMSO (vehicle) as vehicle control. The cleaved 2-cell conceptuses were then selected, washed and cultured in fresh medium for further 24 hours. Numbers of conceptuses reaching denoted cleavage stages were counted and presented. Number of independent trials: 15.