Effects of dietary energy level and source on foetal development and energy balance in concurrently pregnant and lactating primiparous rabbit does

Abstract

Abstract The aim of this experiment was to study the effects of dietary energy level and source on foetal growth and survival and mobilization of body stores in concurrently pregnant and lactating primiparous rabbit does. Does were given a moderate-energy diet (≍9·9 MJ digestible energy (DE) per kg dry matter (DM); group M, no. = 23) or a high-energy diet (-12·2 MJ DE per kg DM). In this latter 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 gestation-lactation. During the first 21 days, the DE intake and milk production 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 energy level of the diet did not improve foetal survival or growth in concurrently pregnant and lactating primiparous does. On the contrary, it could reduce the mobilization offat stores, especially if the energy source is starch.