Factors affecting growth of ovine foetuses during early gestation

SUMMARY Year, type of gestation (single or twin foetuses) and age of foetus all had highly significant independent effects on both foetal weight and length (P>0·01). Twin foetuses were both longer and heavier than single foetuses at 21 to 30 days post coitum. Continuous illumination, continuous darkness and intermittent light appeared to reduce foetal length and weight (P>0·05). Control foetuses were longer and heavier than those on other treatments. Neither feeding level (75 to 150% N.R.C. maintenance requirements) nor body weight of the dam had significant effects on foetal size within the age range studied.