EFFECTS OF DIETARY ENERGY-LEVEL AND SOURCE ON FETAL DEVELOPMENT AND ENERGY-BALANCE IN CONCURRENTLY PREGNANT AND LACTATING PRIMIPAROUS RABBIT DOES

The aim of this experiment teas to study the effects of dietary dietar y energy level and source on foetal growth and survival and mobilizati on of body stoves in concurrently pregnant and lactating primiparous r abbit does. Does were given a moderate-energy diet (approximate to 9.9 M) digestible energy (DE) per kg dry matter (DM); group M, no. = 23) or a high-energy diet (approximate to 12.2 MJ DE per kg DM). In this l atter case, additional energy came from starch (group S, no. = 23) or starch and fat (group F, no. = 22). Primiparous rabbit does were mated within 12 h after parturition and were slaughtered on day 28 of gesta tion-lactation. During the first 21 days, the DE intake and milk produ ction were higher in the group F than in the groups S and M (P < 0.05) . On day 28 of pregnancy, the weight of adipose tissues and liver, as well as the lipid content of the carcass, were higher in the groups S and F than in the group M (P < 0.05). Foetal survival and weight were similar in the three groups. These results indicate that increased ene rgy level of the diet did not improve foetal survival or growth in con currently pregnant and lactating primiparous does. On the contrary, it could reduce the mobilization of fat stores, especially if the energy source is starch.