A well-managed grass sward provides the herd with a largely complete diet including a source of energy, protein as well as many essential minerals and vitamins. In the Lely Astronaut this grazed grass is supplemented with concentrates to bridge any nutritional gap as well as to provide additional energy and protein for sustainable milk production and increased cow health.
Like our housed systems a grazing system operates on the same principle of Free Cow Traffic which means the cow is free to travel to the Lely Astronaut as she pleases. At grass the search for additional energy in the form of concentrates or new fresh grass provides the motivation for the cow to travel. Lely has developed a range of strategies to assist with feeding at grass:
• Grass Management and Budgeting of grass allocation is essential. Over allocation of grass will result in overfull lazy cows which are more likely to lie down than travel to the robot. Under allocation of grass will result in cows visiting the robot too early in search of fresh grass or concentrates substitution in the absence of adequate grass for maintenance and milk production. With the correct allocation cows will receive adequate DM intake and energy whilst still being motivated to visit the robot.
• The right type of concentrates is also important. To attract the cows to the robot it is important that a good quality concentrate is fed which is at least 10% higher in energy than grass. The concentrate itself needs to be tasty and palatable and easy for the cow to ingest whilst in the robot.
• It is important that adequate concentrates are fed in the robot to supplement the diet as well as reward the cow for coming from the field and visiting the robot. A minimum amount of 2 kg per day of concentrates is recommended to reward the cow with at least 1 kg per visit to keep her interest.
• If less than 6KG DM is available from grass, a buffer feed is required. Buffering with a good quality feed, crop or mix can increase rumination leading to more active cows which will produce more milk.
• If more than 12KG DM is obtained from grass, no buffer will be needed as long as sufficient grass is available for all cows. A buffer feed can be utilized in times of poorer grass quality or in poor weather conditions such as prolonged drought or on wet days.
• Grass quality varies throughout the grass growing season. Therefore it is important to review feed tables in T4C when grass quality deteriorates to avoid a drop in milk yields. The feed tables should reflect the amount of milk the cow can produce from the base diet. If this figure is incorrectly represented in the feed tables, consequently yield may suffer.
• On wet days where required DM intakes are harder to achieve, a temporary increase in concentrates can be provided to all animals or specific groups in the herd via the temporary increase setting in T4C. A temporary decrease may also be actioned when required.
For more information about utilizing grazed grass as part of the diet and selecting the best concentrate supplementation and buffering strategy for your herd, contact your local Lely FMS representative or your local Lely Center.