Onderwerp scriptie

Optimizing grazing management in automatic milking farms - Guillaume Haelewyn

The two main challenges for grazing in Automatic Milking farms are to insure good cow traffic (to motivate cows to get milk and go grazing) and to keep an even robot utilization during days and nights. Different grazing management options such as the number of daily pasture allocations, the water supply location or the feed supplementation at the feed fence are used to achieve farmers’ objectives regarding milking frequency (MF), percentage of grazed grass in cow diet and grazing management time for instance.

Grazing in automatic milking (AM) farms is an interesting tool to lower production costs and improve cow welfare (including health). The two main challenges for grazing in AM farms are to insure good cow traffic (to motivate cows to get milk and go grazing) and to keep an even robot utilization during days and nights. Different grazing management options such as the number of daily pasture allocations, the water supply location or the feed supplementation at the feed fence are used to achieve farmers’ objectives regarding milking frequency (MF), percentage of grazed grass in cow diet and grazing management time for instance.

A literature review of the state of the art of grazing management in AM farms was first performed. Lely national farm management support managers were interviewed worldwide to study grazing management country specificities in AM farms. A field research was then performed on twenty-two grazing AM farms in the Netherlands, France and Ireland. An online survey was conducted to gather data from grazing AM farms worldwide and learn more from AM farmer experiences of grazing management.  

It was shown in this study that none of the grazing strategies, i.e. continuous, rotational and strip grazing, were unsuitable to AM farms. However, farms grazing pastures far from the barn and targeting high grazed grass dry matter intake were more likely to choose for strip than for continuous grazing. Grazing management choices were found to be very heterogeneous among rotational grazing farms which would argue for a different definition of rotational grazing farms for further researches. The MF difference between the indoor period and the grazing season was not shown to differ according to the water supply locations (in the barn only or also in pastures) and the number of daily pasture allocations. Grazing management choices were find to largely interact with each other and with the farm characteristics such as the climate, the distance between the barn and the pasture or the grazed grass dry matter intake. This was shown to lead to major difficulties for standardizing grazing management in AM farms.

Student: GPG Haelewyn

Supervisor: dr ir E Bokkers

36 Ects