Abstract #140

# 140
Dynamic feed delivery times of an automatic feeding system and the effects on feeding behavior of dairy cows.
Rosemarie Oberschätzl-Kopp*1, Bernhard Haidn2, Rudolf Peis2, Klaus Reiter2, Heinz Bernhardt3, 1Lely Germany GmbH, Waldstetten, Germany, 2Bavarian State Research Center for Agriculture, Poing-Grub, Germany, 3Technical University of Munich, Freising, Germany.

Automatic feeding systems (AFS) are gaining importance due to rising demands on performance-related feeding and welfare of cows. Nevertheless, under practical conditions AFS are used with static settings for feeding times and frequencies without considering animal demands. Therefore, the objective of the study was to develop a dynamic way of feeding with an AFS concerning behavior of dairy cows and to analyze the effects of this feeding strategy on feeding behavior (frequency, duration, daily rhythm of visits at the feed bunk, meal criteria, frequency and duration of cows’ meals). 80 lactating dairy cows housed in a barn with an AFS and an automatic milking system were subjected to each of 2 treatment periods with 7: static (A) and dynamic (B) feeding times per day in winter and summer time (n = 6 d/period). During period A cows were fed at 815, 1115, 1400, 1600, 1945, 2315 and 345 h. A real time location system collected individual animal behavior. Based on real time procession of positioning data regarding cows’ duration of stay at the feed bunk, decisions were made about starting time of AFS feedings. A programmed algorithm using the median with boundaries time (60 s) and way (1 m) summarized positioning data. Meal criteria were calculated by fitting mixed models to observed frequency distribution of loge-interval lengths between feed bunk visits. Feedings in both trial periods in winter led to similar proportions of animals at the feed bunk with maxima of about 80% while cows left the feed bunk significantly (P = 0.002) earlier in the first 60 min after feeding during periods B. The daily duration of stay at the feed bunk did not differ in winter periods, whereas cows stayed there longer (P = 0.003) in summer period B (5.42 ± 1.53 h/d). Meal criteria tended to be on a lower level during periods B, whereas there was a difference observed in summer investigation (39.74 ± 23.07 min vs. 32.63 ± 30.56 min, P = 0.02). Primiparous dairy cows showed slightly higher average duration of meals than multiparous cows during summer period B (1.03 ± 0.75 h vs. 0.93 ± 0.42 h). The results demonstrate that dynamization of feed delivery times by an AFS might be beneficial for an even distribution of feed bunk visits and meals, particularly in the summer time.

Key Words: automatic feeding system, dynamic feeding, animal behavior