In 2013 Lely Farm Management Support commenced a research study involving 500 Dutch Astronaut farmers. 200 of these farmers put their cows to out to graze. Most of them− 40%−opened the barn doors in May. The study analyzed the effect of introducing grazing. A comparison was made between the month prior to the start of grazing, in which the cows were still indoors and the month in which grazing was introduced. The first month after the cows started to go to the pasture was also taken into account.
Management, Grazing, T4C & InHerd
A good grazing setup with automatic milking requires some specifications in order to ensure enough voluntary milkings. A selection gate like the Grazeway belongs to the basics. This selection gate steers the cow into the correct field or back into the barn. From the moment the cows started to go to the pasture the number of milkings only decreased by 2% to 2.56 milkings/cow/day (figure 1). These minor changes were caused by changes to both the distance between the robot and the pasture as well as the ration. The number of refusals, a monitor of good visit behavior, also decreased. They dropped from 3.4 to 2.7 refusals (Figure 1). The cows were still very motivated to visit the robot. So, although the introduction of grazing brought changes to visit behavior, good results were still achieved. It is important to understand how cows’ motivation to visit the robot changes. In an indoor system, cows are motivated by the concentrate fed in the robot. In a grazing system the palatability of the fresh grass can be used as motivator. The reward for visiting the robot is the chance to access a new field of fresh grass.
If cows switch to a different ration, this will affect concentrate intake. One of the reasons for grazing is to fully utilize the high nutritional value of fresh grass and therefore reduce the amount of concentrate. The amount of concentrate per 100 kg milk decreased from 21 to 20 kg (Figure 2). On an average farm with 4000 kg milk/robot/day this means a saving of 40 kg of concentrate. That could reflect $11.42/day. The different visit behavior of the cows also responds in a slightly higher percentage of rest feed. This rest feed reflects the amount the cows were not able to eat. It does not mean leftovers in the feed bin. Pay attention to the cows that visit the robot less often and therefore have no opportunity to eat all their concentrates.
You will notice that the visit behavior of the cows will change slightly when they are grazing. This is not necessarily a negative development, but it is important to keep an eye on the concentrates. Figure 2 shows a slight decrease in concentrates per 100 kg milk, along with an increase in the percentage of rest feed. Use the possibilities offered by fresh grass and adapt to the changes it might bring with regard to management. If you would like to know more, you can either find more information on grazing here, or you can contact your local Farm Management Support Advisor.