Does a low quality diet impact the success of twin pregnancy and the carcass quality of meat producing lambs?
Abstract
Perturbations of the prenatal and post-natal environments are known to have metabolic, physiological and behavioral impacts later in life. This study investigated the effects of low quality versus high quality diets without complementation from mid- to near-term gestation on growth capacities, metabolic profile and carcass quality of 5 month-old meat producing lambs. Between weeks 11 and 19 of pregnancy, multiparous Romane ewes were fed ad libitum either a high quality/low fiber hay (well-fed; covering 100% of energy and protein requirements; n = 15) or a low quality/high fiber hay (restricted; covering 50-70% of protein and energy requirements; n = 15). The underfed state of ewes fed the low quality hay was ascertained by the increased plasma level of non-esterified fatty acids and beta-hydroxybutyrate relative to well-fed ewes, while those of glucose, urea and amino acids decreased. The maternal dietary restriction did not impact pregnancy success or lambs' body weight at birth. No strong differences were recorded between lambs born from well-fed and restricted ewes in terms of morphometric, metabolic profile and growth or slaughter measurements. These results are of fundamental interest to the field of ruminants' adaptation to variability of their forage quality induced by climatic perturbations.