Total mixed ration for dairy cows

Project Manager: Eva Spörndly, Department of Animal Nutrition and Management, SLU.

Project Group: Mikaela Lindberg (ex Patel), Department of Animal Nutrition and Management, SLU and Torbjörn Lundborg, Växa Sverige

Presently, approximately one third of the organic milk producers in Sweden have AM (automatic milking). Offering the feed as a total mixed ration (TMR) has proved to be a rational way of achieving a high feed intake and is therefore especially interesting for the organic producer. The problem is that TMR combined with AM is claimed to lead to low milking frequencies with low milk yields as a result.

Experiments that compare TMR with separate feeding in AM systems are few and do not cover the feeds and cow traffic systems common in Scandinavia. Furthermore, the response may differ depending on the type of cow traffic system that is practiced. Therefore the overall objective of this project is to study if TMR is an economical feeding system on organic AM farms and what type of cow traffic system is best in combination with TMR.

Feeding TMR will be compared with feeding forage and concentrates separately on diets calculated according to the rules for organic production. Three experiments will be performed, each lasting over a period of ten weeks and with a different cow traffic system: free cow traffic and two types of guided cow traffic systems. The guided cow traffic systems will be with selection gates where the cows with milking permission in one experiment will be guided to milking before the can access the feeding area and in the second experiment the cows will access the feeding area directly and those with milking permission will be guided to milking on their way back to the resting cubicles.

Production parameters, feed intake and cow traffic will be monitored automatically in the experimental barn. A field study will also be performed on commercial organic AM farms using diets with mixed feeds to study the advantages and disadvantages of combining AM with TMR.

Our hypothesis is that higher milk yields can be achieved with TMR (compared to separate feeding), but only when guided cow traffic is practiced.