The Effect of Restricted Nutrition on Ewe Milking Performance and Lamb Growth Characteristics in Creep Feeding Conditions.

Nutrient deficiency during lactation period negatively affects dams milk production and lamb growth performance. However, the effect of ewe nutrition level on growth rate of Karacabey Merino lambs raised with access to creep feeding is not clear. Therefore to study these effects, a total of 84 single lambed Karacabey Merino ewes (aged 3, 4, 5 years old, 68.05±0.96 kg of live weight (LW); 2.64±0.07 of body condition scores (BCS)), and their lambs (n=84) were divided into two feeding treatment groups: group with 32-35% (energy and protein) nutrient restriction (restricted feeding; RF) and control (control feeding; CF) group according to 100% of nutrient requirements. Lambs had free access to concentrate feed in creep feeding conditions until 96 days of weaning. Lactation milk yield was higher in CF group than RF group (P=0.01). Except for milk fat content (P=0.495), milking characteristics as daily milk yield, protein, lactose, and nonfat solids (NFS) contents of milk were found higher (P≤0.001) in CF group than RF group. Significant interaction was observed between feeding treatment groups (RF and CF) with lamb gender on the daily weight gain (P=0.01) and weaning weight (P=0.036) of the lambs. Male lambs in CF group were heavier than male lambs in RF group (P=0.01) while female lambs in both groups had similar weaning weight (P>0.05). Growth performance of male lambs was negatively affected by restricted nutrition of their dams, while no significant difference was observed in female lambs. Restricted ewe nutrition negatively affects the potential growth rate of suckling lambs in creep feeding condition. [ABSTRACT FROM AUTHOR]