A higher feed efficiency is directly linked to better roughage utilisation. This is the concision of researchers from the Animal Breeding and Genomics group at Wageningen Livestock Research based on analysis of a data set containing the feed intake, weight and milk production data of more than 3000 cows.
2021 年 8 月的指数运行中， 净价值 (NM$) 计算方法正式更新。在过去的几年里，饲料效率变得日益重要，也因此得到越来越多的关注。此次净价值更新中的最大变化是增加了饲料节约指数 (FSAV)，其在总净价值指数中的占比为 13%。去年的12月份，CRV 就已引入独特的饲料效率育种值，该值最初的计算基于 2000 多头泌乳奶牛每天的真实采食量数据。独立研究显示了该育种值对农业产业的影响和重要性。
High intake, less efficient
In their analysis, the researchers investigated - among other aspects - the (genetic) relationship between feed efficiency and the feed intake capacity. Breeding for feed intake capacity reduces the feed efficiency, however breeding for feed efficiency traits also reduces the feed intake capacity. This might seem to be unfavourable, but it is not according to Professor Roel Veerkamp. ‘Cows with a reduced feed intake capacity are not a disadvantage as long as the feed they do eat is efficiently converted into milk production’, he states. ‘The additional feed intake of cows that eat a lot does not translate into higher milk production. In other words, they produce less efficiently, partly because they are heavier.’
Concentrate feed intake efficiency not hereditary
The researchers also focussed on whether breeding for feed efficiency results in cows that need a higher concentrate ration to achieve the same milk production. They concluded that cows with a high total feed efficiency also utilise the roughage component of their ration efficiently. The researchers did not find any genetic differences in concentrate feed intake efficiency. According to them - for practical purposes in the Netherlands and Flanders - there seems to be little advantage in distinguishing between roughage and concentrate intake efficiency.