Production and management in automatic milking systems

Abstract: Different cow traffic systems are used to guide the dairy cows to make them pass the milking unit in automatic milking systems (AMS). Several studies have compared milk production in different cow traffic systems but there were little evidence that one system has a higher production than another. It is likely to believe that the farmers’ management, engagement and dedication have greater importance. Therefore, this study investigated which factors affect milk production in AMS. The study consisted of a literature study, a questionnaire sent out to Swedish dairy farmers with AMS, collection of key figures from the participating farmers’ management software and six interviews with selected dairy farmers who were successful in their production. Results from the questionnaire were compared to production variables from the management software. Milk production was defined as milk per milking unit and day (MPu) and milk per cow and day (MPc). It was found that traffic system had no impact on milk production and it was rather the farmers’ management that had importance. Farms feeding partly mixed ration (PMR) had greater MPu (113 kg higher, p<0.05) and a tendency for greater MPc (1.4 kg higher, p<0.1) and less time unoccupied in the milking unit (4.5 percentage points lower, p<0.05) compared to farms feeding only roughage in the feed bunk. Farms with high part of Jersey cows milked in AMS had lower MPc (0.08 kg lower per each extra percentage point of Jersey, p< 0.01) and a tendency for lower MPu (3 kg lower per each extra percentage point of Jersey, p<0.1). Farms with high bulk tank somatic cell count (SCC >250) had both lower MPu (227 kg lower, p<0.001) and MPc (3 kg lower, p<0.01) compared to farms with SCC ≤250. Number of cows fetched to the milking unit had no effect on MPu or MPc. However, it seems important to fetch selected cows that do not milk voluntary. Farms with slatted floors had lower MPu (127 kg lower, p<0.05), MPc (3 kg lower, p<0.05) and more time unoccupied in the milking unit (4.5 percentage points higher, p<0.05) compared to farms with solid floor.