Feeding behaviour of dairy cows in an automatic milking system at two different feeding regimes

摘要

In this study the feeding behaviour of a full sized herd of 52 dairy cows was investigated. comparing when feeding roughage was given twice per day (08:00 and 16:00) with six times per day (00:00; 04:00; etc) The same amount of roughage was given during both treatments. The cows were fed concentrate according to yield and milked in a single box. Individual cow were identified at the manger 10 minutes after each feeding. In the experiment 26 and 78 feeding occasions were studied for two and six times roughage feedings per day respectively. At two times feeding the ranking order of the herd was determined in three levels; high-, intermediate- and low-ranking. Social rank for 44 animals was determined. The method used was the direct access-rate to the manger using the hypothesis that cows with a low social status have a lower direct access-rate to the feeding manger than cows with an intermediate or high social rank. When roughage was given twice-daily low-ranking cow s had a direct access -rate of20 percent of the feeding occasions. Intermediate-ranking cows and high ranking-cows had an immediate access, rate of 35 percent and 45 percent respectively. When fed roughage six times daily the intermediate-ranking cows did not changed their feeding behaviour. The high-ranking cows visited the feeding manger less often when the feeding frequency was increased. The low-ranking cows could improve their direct access-rate to feeding manger from 20 1 to 26 percent. The only occasion when the low-ranking cows were more reluctant to show up shortly after feeding was at 04:00. It is concluded that when limited eating space at the manger is available an increased feeding frequency of roughage from two to six times per day improves the accessibility for cowswith a low social rank. Intermediate ranked cows do not change visiting behaviour whereas high-ranking cows adjust their visiting pattern by visiting the feeding manger less frequent at 04:00 when fed six times daily compared with the other two group ofcows.