13 SEP 2023

Early rumen development in sheep and cattle at weaning

Weaning marks a critical transition period in the lives of sheep and cattle, as it entails the gradual shift from milk-based nutrition to solid feed consumption.

The rumen: a digestive powerhouse 

One of the most significant changes during this period is the development of the rumen, a specialized stomach compartment responsible for the fermentation and breakdown of complex plant materials. Early rumen development is a pivotal phase that directly impacts the animals' ability to efficiently digest and utilise forage-based diets.  

During the suckling phase, the rumen is relatively undeveloped, as milk is the primary source of nutrients. With the onset of weaning however, there is a shift in dietary composition, prompting the need for significant rumen development to accommodate the transition to solid feeds. The quality of care and nutrition that young lambs and calves receive (or don’t receive) at weaning time, directly impacts the life-time efficiency of this potential “powerhouse.”

Stages of rumen development 

Pre-ruminant phase: At birth, the oesophageal groove allows milk to bypass the underdeveloped rumen and flow directly into the abomasum (true stomach). This bypass mechanism ensures that milk proteins are properly digested and absorbed before the rumen becomes fully functional. 

Initiation of solid feeds: As weaning begins, the intake of solid feeds stimulates microbial growth in the rumen. This microbial population plays a vital role in the breakdown of complex carbohydrates, protein and fibre, that would otherwise be undigestible by the animal. The microbes gradually establish a symbiotic relationship with the developing ruminant, aiding in the fermentation and digestion of these materials. 

Rumen development: Over a rather short period of time, the internal surface area of the rumen increases through the growth of papillae - finger-like projections that enhance nutrient absorption. 

Factors influencing rumen development 

Several factors influence the pace and success of early rumen development in sheep and cattle during weaning: 

  • Dietary composition: The introduction of solid feeds that are rich in starch and fibre encourages rumen development and fermentation.  
  • Microbial colonisation: The establishment of a diverse and stable microbial population in the rumen is crucial. 
  • Genetics: Genetic factors can influence the rate of rumen development. Some breeds may exhibit faster rumen maturation than others. 
  • Management practices: Proper management practices, such as reducing stress and maximising nutrition contribute to the smooth and rapid transition of the animal's digestive system into a system that can be significantly more efficient for life! 

Where to from here? 

Early rumen development during the weaning phase in sheep and cattle is a dynamic process that shapes the animals' ability to digest fibrous plant materials more effectively for life. What does this mean? It means a more efficient animal on the farm that can grow or reproduce better, all on less feed.

A rumen that can absorb more nutrient per mouthful of feed, will gain more energy and protein that leads to greater resistance to parasites and disease, as well as more efficient production of meat, milk, wool and progeny – all of the saleable product for a livestock enterprise.

Article written by Mark Dearing, Livestock Production Specialist, Elders Rosewrothy.