Sheep are fascinating animals, particularly when it comes to their ability to digest fibrous plant material efficiently with their unique digestive system.
As ruminants, they possess a highly specialised digestive system that allows them to break down tough grasses, hay, and other forages that many animals would struggle to process. This unique adaptation plays a crucial role in their overall sheep nutrition, health, productivity, and well-being. By understanding sheep digestive systems, you can ensure your livestock remain in top condition through key farming milestones, including tupping and lambing.
How many stomachs does a sheep have?
While it may seem like they have multiple stomachs, sheep actually have one stomach divided into four distinct compartments: the rumen, reticulum, omasum, and abomasum. With sheep's anatomy and physiology, means each of these compartments has a specific function, working together to extract nutrients from plant material efficiently.
Sheep digestive systems
Rumen – The largest compartment, acting as a fermentation vat where bacteria and microbes break down fibrous plant material, producing essential nutrients like volatile fatty acids. It can hold up to 25 litres in an adult sheep.
Reticulum – Often called the "honeycomb stomach" due to its structure, it helps trap indigestible objects and works with the rumen to regurgitate cud for further chewing, aiding digestion.
Omasum – The compartment responsible for absorbing water and nutrients from partially digested food. It has many folds (like pages in a book) to maximise absorption.
Abomasum – Known as the "true stomach," it functions similarly to a monogastric stomach, using enzymes and acids to digest food before it moves into the intestines for further nutrient absorption.
How a sheep’s stomach aids digestion
The digestive process in ruminants is complex and involves several stages to ensure maximum nutrient absorption. It begins when the sheep consumes forage, which is quickly swallowed and stored in the rumen, the largest of the four compartments. The rumen is a fermentation vat filled with microorganisms that help break down fibrous plant matter, producing essential nutrients such as volatile fatty acids.
Next, the partially digested food moves into the reticulum, where smaller particles are separated from larger, undigested fibres. These larger pieces are regurgitated as cud, which the sheep chews again to break it down further before swallowing it once more. This process, known as rumination, is essential for effective digestion.
The food then passes into the omasum, where water and further nutrients are absorbed. Finally, it reaches the abomasum, often referred to as the "true stomach," as this is where enzymatic digestion takes place, much like in a monogastric (single-stomach) animal. The remaining nutrients are absorbed in the intestines before waste is expelled.
Things to consider when feeding ruminant sheep
Understanding the ruminant digestive system in sheep is crucial when it comes to providing them with the right nutrition. Since their digestive system relies heavily on microbial fermentation, sudden changes in diet can disrupt the delicate balance of microbes in the rumen, leading to digestive upsets such as bloat or acidosis. It’s essential to introduce any new feed gradually to allow their stomachs to adjust.
High-fibre diets, such as grass, hay, and silage, are the best foundation for a sheep’s diet, as they promote healthy rumen function. While supplementary feeds like grains can be beneficial, they should be provided in controlled amounts to avoid overloading the rumen with rapidly fermentable carbohydrates. Additionally, ensuring a consistent supply of fresh water and essential minerals supports overall digestive health and keeps sheep thriving.
By understanding how the stomach of a sheep functions, farmers and smallholders can make more informed feeding decisions, ensuring their flock remains healthy, productive, and well-nourished.
Would you like to explore specific feeding plans for different stages of sheep growth? Speak to our team at 01451 830 400.