Bøe K E, Dønnem I
J Anim Sci. 2015 Oct;93(10):4819-25. doi: 10.2527/jas.2015-8955.
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.
本研究的目的是调查冷冻青草青贮饲料对母羊采食量、采食偏好和采食行为的影响。进行了两项试验，每项试验采用拉丁方设计，涉及8只怀孕母羊，有4种处理方式：1）冷冻青贮饲料；2）部分冷冻青贮饲料；3）冷冻切碎青贮饲料；4）未冷冻青贮饲料（对照）。在试验2中，第1组的母羊饲喂低干物质含量（LDM）的青草青贮饲料，第2组的母羊饲喂高干物质含量（HDM）的青草青贮饲料。在两项试验中，每个处理期持续14天。进行了采食偏好测试，在转换设计中，母羊可以在两种试验饲料处理之间选择1天，以便它们接触到4种处理的所有两两组合。在试验1的每个试验期的最后一天，通过直接观察4小时对采食行为进行评分。在试验1（P<0.0001）和试验2（P = 0.03）中，采食后前4小时的采食量在冷冻青贮饲料处理组最低，在对照组最高。采食后前4小时的干物质采食量在HDM处理组高于LDM处理组（P = 0.005）。试验1中，冷冻切碎青贮饲料处理组的每日总采食量最低，未冷冻青贮饲料处理组最高（P = 0.02）。在试验2中，各处理之间的日采食量没有差异（P = 0.32）。LDM处理组的每日总采食量高于HDM处理组（P<0.0001），但干物质采食量没有差异。在考虑前4小时（P = 0.12至P = 0.86）或整个24小时期间（P = 0.25至P = 0.53）时，对不同饲料处理的偏好没有差异。在对照处理中正常采食的时间较长，在冷冻青贮饲料处理中较短（P<0.0001），而从冷冻块上撕下饲料采食所花费的时间则呈现相反的模式（P<0.0001）。我们得出结论，冷冻青贮饲料在采食后前4小时的摄入量较低，但冷冻青贮饲料对每日采食量的影响非常适中。部分解冻或切碎可提高采食量。处理对采食偏好没有显著影响。饲喂冷冻青贮饲料增加了从冷冻块上撕下饲料采食所花费的时间，但总采食时间适度增加。
