The effect of round-bale feeder design and roughage type on feed wastage in sheep feeding.

Feeding big round-bales in round-bale feeders are known to reduce labor and costs. However, one disadvantage is the high feed wastage. The aim of these experiments was therefore to investigate the effect of feeder design, type of roughage and size of round-bales on feed wastage in sheep. Four round-bale feeders (Diagonal Rail Sheep Circular Feeder (RD), Knarrhult Flexible Round-Bale Feeder (KR), Telemark Round-Bale Feeder (TR) and Standard Sheep Circular Ring Feeder (RV)) were distributed into four identical experimental pens and used in both experiments. In Experiment 1, two types of roughages were used; Roughage 1: low-quality, grass silage harvested at late stage of maturity with dry matter (DM) content of 560 g/kg and Roughage 2: high-quality, hay harvested at an early stage of maturity with DM content of 738 g/kg. In Experiment 2, ewes were offered hay harvested at the late stage of maturity with DM content of 766 g/kg as half and whole round-bales. In both experiments, four groups of 10 ewes of the Norwegian White breed were rotated between the experimental pens and each treatment lasted for 4 days. Feed wastage (roughage on the ground surrounding the feeder) was collected daily. The amount of feed wastage was generally high. The type of roughage (Experiment 1) had a large effect on feed wastage (P < 0.001), where Roughage 1 had a mean feed wastage of 1.88 kg DM/day per ewe and Roughage 2 had 0.48 kg DM/day per ewe. When Roughage 1 was provided, it was evident that the ewes pulled out the long fibrous stems of the feeders and left them as wastage while selecting the leaves. This was not the case for Roughage 2. When feeding half round-bales (Experiment 2), the mean feed wastage was 1.50 kg DM/day per ewe compared to 2.88 kg DM/day per ewe when feeding whole round-bales (P < 0.001). This is probably due to the ewes spending more time eating with their heads inside the feeder when fed half round-bales (P < 0.001) and thus dropped more of the potential wastage inside the feeder. Less feed inside the feeder may also be the reason that feed wastage decreased gradually from Day 1 to Day 4 in both experiments (P < 0.001). Feeder design also had a significant impact on feed wastage (P < 0.001). We conclude that providing early harvested roughage and feeding half round-bales significantly reduced feed wastage.

The effect of frozen grass silage on the feed intake and feeding behavior of pregnant ewes.

The aim of the current study was to investigate the effect of frozen grass silage on the feed intake, feed preferences, and feeding behavior of ewes. Two experiments were conducted, each involving 8 pregnant ewes in a Latin square design with 4 treatments: 1) frozen silage; 2) partly frozen silage; 3) frozen, chopped silage; 4) and unfrozen silage (control). In Exp. 2, the ewes in square 1 were fed grass silage with low DM content (LDM) and in square 2 the ewes were fed grass silage with high DM content (HDM). In both experiments, each treatment period lasted for 14 d. A feed preference test was conducted, where the ewes could choose between 2 of the experimental feed treatments for 1 d in a changeover design so that they were exposed to all pairwise combinations of the 4 treatments. On the last day of each experimental period in Exp. 1, the feeding behavior was scored by direct observation for 4 h. In Exp. 1 ( < 0.0001) and in Exp. 2 ( = 0.03), feed intake in the first 4 h after feeding was lowest on the frozen silage treatment and highest on the control treatment. The DMI in the first 4 h after feeding was higher ( = 0.005) in the HDM treatment than in the LDM treatment. The total daily feed intake in Exp. 1 was lowest on the frozen, chopped silage treatment and highest on the unfrozen silage treatment ( = 0.02). In Exp. 2, daily feed intake did not differ ( = 0.32) among treatments. Total daily feed intake was higher ( < 0.0001) in the LDM treatment than in the HDM treatment but there was no difference in the DMI. There was no difference in the preference for the different feed treatments, when considering either the first 4 h ( = 0.12 to = 0.86) or the whole 24-h period ( = 0.25 to = 0.53). Time spent eating normally was longer on the control treatment and shorter on the frozen silage treatments ( < 0.0001) whereas time spent eating by tearing off feed from the frozen block followed the opposite pattern ( < 0.0001). We conclude that intake of frozen silage was lower for the first 4 h but that frozen silage had a very moderate effect on daily feed intake. Partly thawing or chopping improved the feed intake. Treatment had no significant effect on feed preferences. Feeding frozen silage increased time spent tearing off feed from frozen block, but total time eating was moderately increased.