Effects of Ad Libitum Silage Feeding Systems on Ewe Performance and Floor Wastage

Abstract

Two experiments were conducted to investigate how silage intake, ewe weight gains, lambing performance and floor wastage of feed were affected by ad libitum silage feeding systems differing with respect to feeder space allowance, feeding frequency and feeder design. In Experiment 1, 162 ewes of the Icelandic sheep breed were divided into three treatments. Feeding twice a day in a conventional feeder type (A) for loose silage with 0.40 m feeder space per animal (Treatment 1-1) was compared with feeding whole round bales in a new feeder type (B) with an average space of 0.11 m per animal, and also with two different leftover allowances at feeding: approximately 5 and 15% in Treatments 1-2 and 1-3, respectively. In Experiment 2, 168 ewes of the Icelandic sheep breed were divided into three treatments. Treatment 2-1 was as Treatment 1-1 in Experiment 1, but here it was compared with feeding round bales cut in half in a third type (C) of feeder, with two different levels of feeder space allowance: average 0.11 m (Treatment 2-2) and 0.09 m (Treatment 2-3) per ewe. In Experiment 1, no significant differences in ewe weight gains or lambing performance were found between treatments. However, the silage intake was, on average, 10 and 20% higher in Treatments 1-2 and 1-3, respectively, than in Treatment 1-1. In Experiment 2, ewe weight gains differed significantly (P<0.05) between treatments, being 13.1, 11.5 and 9.6 for Treatments 2-1, 2-2 and 2-3, respectively, which parallels the trend found for intake in the treatments. The feed wastage on the floor was about 0, 4-5 and 1% for feeders A, B and C, respectively. It is concluded that when ewes are fed round bale silage ad libitum, continuous access feeding regimes with restricted feeder space allowance can be an interesting alternative, especially on farms where labour is a limiting factor on productivity.