Calf rearing: Developing the rumen
When a calf is born their digestive system is not fully developed yet, during the calf rearing phase one of the primary objectives is transitioning the calf from a milk based diet to a diet based on solid feed.
In a new-born calf the abomasum is the largest and most developed stomach, this stomach is responsible for the digestion of milk hence why the calf relies on milk in the early stages of their life.
The rumen is responsible for digestion of forage, so for the calf to move from a milk to a forage-based diet the rumen must be developed sufficiently at the time of weaning. The most important factors of rumen development are concentrate feeding, feeding of forage/fibre and access to clean water, we will look at why these are important below.
Concentrate feeding is the most important factor in the development of the rumen, through digestion of concentrates the growth of rumen bacteria is promoted.
Concentrates should be introduced from 3 days of age. Initially calves will just nibble and nose at feed, so a handful for each is sufficient. Gradually increase the amount being fed up until calves are eating 1kg of concentrate daily at weaning. Select a high quality, easily digestible ration with adequate protein and energy content. Coarse rations tend to be the best as they are the most palatable, encouraging the calves to eat more.
Calves should have access to fresh clean water from 3-4 days, water is crucial to provide a good environment for the development of rumen bacteria. Water used in milk replacer is not a substitute for fresh water as this will go directly to the abomasum for digestion.
Calves that have free access to water will also have higher daily gains in comparison to those who do not.
Fibre (Hay Straw)
Fibre is key to the development of rumen muscle and tissue via the scratch factor.
High quality hay or straw should be introduced before calves reach 2 weeks old. Avoid overfeeding of hay/straw as this will lead to a reduced intake of concentrates and "pot-bellied" calves as the rumen struggles to digest large quantities of forage. Keep forage clean and separate from the calves bedding material to reduce the risk of calves consuming contaminated bedding.
For further advice on any of the above, please contact a member of the Moocall team to speak to some of our breeding specialists on +353 1 96 96 038 or email firstname.lastname@example.org