240 Evaluating the Effect of Hay, Fed Ad-Libitum or Controlled, or Soybean Hulls During Gestation on Body Weight and Dry Matter Intake of the Ewe and Body Weight on the Offspring Until Weaning

Abstract

Abstract The objective of this experiment was to evaluate the effect of feeding different types and amount of fiber during gestation on ewe body weight (BW) and dry matter intake (DMI), and lamb BW at birth and weaning (60 d of age). Ninety Dorset × Hampshire ewes were blocked by BW and within each block randomly assigned to 1 of 3 treatments (10 ewes/pen; 3 pens/treatment): ad-libitum hay (CONT), limit-fed hay (LH), and soybean hulls (SH). The concentrate roughage ratio for the LH and SH diets was 1:3. From d 0 (28 d post mating) to d 63, LH and SH ewes were fed using slick bunk management. Ewes in the CONT diet were offered an equal amount of concentrate as LH ewes with ad-libitum access to hay. On d 63 ewes were offered the same diet to meet, but not exceed, maintenance requirements for late gestation. Feed offered and refused were collected daily for LH and SH ewes whereas hay refusal was collected weekly for CONT ewes. Ewe BW was collected on d 28, 34, 76, and 2-d after lambing. Lamb BW was collected at birth and weaning. Data, presented in Table 1, were analyzed as a mixed model considering the fixed effect of treatment and random effects of ewe (pen), pen, and block. Dry matter intake was similar the first 28 d (P = 0.13); however, SH ewes consumed more by d 62 (P = 0.02). As DMI increased, BW of SH ewes also increased during gestation (P ≤ 0.01) but was similar 2-d after lambing (P = 0.21). Lambs born of SH ewes were heavier at birth, but lighter at weaning (P ≤ 0.02). Despite each diet having the same forage concentrate ratio, forage source affected ewe BW during gestation and lamb BW at birth and weaning. Feeding hay ad-libitum or in a controlled manner did not change ewe or lamb BW.