1 Automatic Milking and Grazing

Recent research on how to combine automatic milking (AM) systems and grazing is presented with the objective to summarise the results obtained in an EU-project and discuss these results in relation to present knowledge in the field. Experiments with 24-hour grazing conducted in Sweden showed no difference in water intake between cows with drinking water indoors, and cows with water both indoors and on pasture. Ad libitum supply of silage did not increase milk yield or lower the milking interval compared with 3 kg dry matter*cow*day-1. Free cow traffic (access to feed supplements) gave a significantly lower number of voluntary milkings compared with controlled access. Grazing near the barn (50m) gave a higher milk yield compared with grazing further away (260m). Dutch surveys and studies on AM-farms with grazing showed that selection gates contributed to a lower number of manually fetched animals. In an experiment, the effect of pasture distance (<150m versus>500m) and supplementation level (6 versus 10 kg DM) on milking interval, pasturing time and milk yield was studied. No significant effects of distance or level of roughage supplements on milk yield and milking interval were observed. Case studies on farms in Denmark showed that a relatively high milking frequency was obtained (variation 2.1-2.8) but most cows had to be fetched from the pasture. In periods when many cows were at pasture a decrease in number of milkings per hour often occurred. Cow behaviour was more synchronised at pasture than when in the barn, and only few cows entered the barn alone. In conclusion, automatic milking can successfully be combined with pasture and grazing. High levels of supplementary feeding did not lead to higher production when pasture was available in sufficient amounts but supplementation can be used strategically as a management tool to obtain smooth cow traffic