Cattle and sheep are ruminants. Their stomach is made up of four separate sections (one of which is the rumen) and enables them to digest the cellulose content of plants, which humans are unable to digest. Goats, cervidae (deer, etc) and camelidae (camels, llamas, etc) are also ruminants.

Like all animals, ruminants require two main sources of food: energy-giving substances (sugars, carbohydrates, etc) and proteins. Animals use these different types of food to regulate their temperature, to move, to develop their muscle structure and to ensure the working of their entire metabolism. Food thus plays a major role in animals’ production performance (meat or milk) and reproductive performance.

With a cost of between 45 to 55% of farm expenditure, food is a major item in the farm’s budget. To optimize results it is therefore necessary to ration the animals’ food, i.e. to cover their needs at any given time while taking into account their weight, their physiological state and their level of production.

About 85% of cattle feed comes from forage and grain produced on the farm. The remainder is made up of plant protein sources, mainly soybean cake or rape cake, obtained after the oil has been extracted from the seeds, as well as minerals and vitamins. Regarding available feed, forage maize (used to make maize silage) enables producers to secure their stores of foodstuffs, while increasing the energy value of their feed rations. The type of feed ration, i.e. the respective amounts of the different foodstuffs—grass, forage, grain, oil cake—varies considerably according to the age and type of animal, and the region of production.

When talking of feed, it is important not to forget water. Cattle drink between 30 and 50 litres of water per day, depending on their physiological state, the outside temperature and their feed.

Finally, it must be remembered that the use of meat and bone meal is banned for all herbivores.

Three types of forage crop

We can distinguish between three different types of forage crop: permanent grassland (natural meadow), temporary or artificial grassland, and annual forage crops.

Permanent or natural grassland
Not subject to crop rotation, it is also called permanent meadow: whether through natural grass regeneration or sown over a considerable period of time, it has a complex flora subject to considerable change due to the action of many different factors, and especially to that of the extensive farming methods frequently used. It is mainly located on land which is inaccessible to the plough or which is difficult to work. The grass yield varies according to the composition of the natural flora.
This type of grassland covers around 45 million hectares in the EU, i.e. about 32% of the useable agricultural area.

Temporary grassland
Apart from the fact that its yield is higher than that of permanent grassland, temporary grassland also differs from the latter in that it is included in crop rotation. Replacing another crop, it is then sown, grazed or mown, being kept for a limited period (usually 3 to 5 years), and then ploughed up when the yield is no longer sufficient. It is then replaced by another crop which benefits from the improved soil structure and fertility contributed by the grassland.

It is also called artificial grassland when it is planted with species with high feed value, such as alfalfa or clover.

Temporary grassland covers slightly under 15 million hectares in the EU; it is usually subject to a more intensive farming system, which leads to an increase in available feed even in areas with a poor reputation for grass production.

Annual forage crops
This applies to crops which are only grown for part of the year. Unlike grassland, annual forage crops have a short growing season, which means that, under the most favourable conditions, two or even three crops per year are possible on the same plot of land. Some plants can even be grown between two main crops; in this case they are treated as a catch crop.

It should also be noted that, whereas grassland can be mown several times a year, annual forage crops are usually only harvested once a year. The plants grown are very varied, consisting of legumes (peas, vetch, pigeon beans, crimson clover, etc), grasses (maize, sorghum, oats, barley, winter barley, wheat, rye, etc), crucifers (cabbage, bird rape, rape, etc), and root crops and tubers (especially beet, potatoes and Jerusalem artichoke).

These forage crops are generally considered as a supplementary source of feed, and are used to build up stores for winter or to replace grazing at a difficult time of year.

Production varies considerably from one country to another. It covers 1.7 million hectares in France.

Grass, the main feed used by cow-calf producers

Grass plays the biggest role in feeding suckler cows. 70% of the grass the cow grazes goes to producing beef.

Cow-calf producers and producer/finishers plan feeding on the basis of the grass that is available to them. They manage it in the following way:

> grazing in spring and summer.
The grazing season lasts 7 to 8 months per year. Grazing periods alternate with mowing periods so as to build up stores of forage for winter. However, the nutritional value of grass diminishes with time, and it is often necessary to give the animals feed supplements from the end of summer on. It is important that the livestock be in good shape to confront the rigours of winter, an important time for the producer since this is often the calving season for beef cattle.

> hay consumption in winter.
The hay is produced in spring when there are good supplies of standing grass in the meadows. After the grass has been mown, it is left out to dry in the sun for a few days, before being bundled or baled for storage.

In general, producers of suckler cattle in semi-free range systems attempt to get their animals back into stabling in good shape. During the first months of winter, they then temporarily reduce the energy content of the feed in order to limit the cost, but without cutting down on the supply of nitrogen, minerals and vitamins (which are essential for the reproductive system to work well).

Thus, over a period of one year the weight of suckler cows can vary considerably, by 50 to 100 kg or more. This is because the farming systems have been designed so that, in winter and during lactation, the cows use up the fat reserves that they stored up during the grazing season. Suckler cows have a great capacity to call on their fat reserves. The quantity of an animal’s energy reserves can be measured by observing how fat it is (this must not be confused with the fat grade attributed to the carcass at the abattoir).

Maize and commercial feed is used by fatteners

Fatteners generally use large quantities of maize and commercial feed supplements. In Italy, feeding expenditure is calculated to be 0,30€ per kg growth for a Charolais type animal.

The energy in maize
Maize is a very energy-rich plant, rich in carbohydrates but poor in proteins, which forces the producer to add a protein supplement to the feed ration to ensure that the animals grow properly.

Maize is very widely used as livestock feed because its high starch content gives it such high energy value. It is used either as grain (added to the feed ration or as one of the components of mixed feed), or as the whole plant. Maize can be harvested and stored for silage (stores of forage for cattle in winter) before the grain is completely mature, and used to feed ruminants. This is known as forage maize.

In fattening units in Italy, maize production utilizes the land better by means of irrigation. Most producers grow their own maize and buy grain and protein, while others sell grain and buy standing maize.

The dynamic commercial feed industry
Industrial cattle feed first appeared in Europe in the 1930s. Today, the feed industry plays a central role in European livestock production by contributing to the spread of technical innovations and by organising the different sectors of the industry .

While practically all meat poultry and pigs are fed on these complete feeds, the basic ration for ruminants is mainly provided by forage production on the farm.
These feed rations are supplemented with grain (either produced on the spot or purchased) and oil cake, or commercial feed supplements. The raw materials represent 80 to 85% of the production costs of ‘granules’ (commercial feed). They are composed of around a hundred ingredients: grain, high-protein crops, oil cake, by-products from flour mills and sugar refineries, etc. Among more recent ingredients are cassava, sweet potato, citrus pulp, etc.

Feedstuffs for steers and heifers
These slow-growing animals, which on average are fattened until the age of three years, give beef which is renowned for its quality.

After spending about eight months in pasture with their mother, and after weaning, they alternate phases of grazing to the exclusion of all other feed in spring, summer and autumn, with phases of indoor feeding in winter, when grass no longer grows, based on hay or other stored forage (such as balage), to which is added grain and oil cake.

There are naturally several variations on this classic diet. Feed supplements vary in quantity according to the age at which the livestock is slaughtered. The younger they are to be slaughtered, the more supplements they are given.

Similarly, steers from dairy breeds are weaned when very young; during the first three months of their life, they are given a milk replacement, hay, grain and oil cake, before being put out to graze. They are slaughtered at a younger age than steers from beef breeds.

Feedstuffs for young bulls
With the exception of animals which are to be raised as beef calves and steers, male cattle are fattened and slaughtered young, when they are about 18 months old (they are classified as ‘young bulls’). The meat of young bulls is pale and is mostly sold to the Eastern and Southern European markets.

The feeding of young bulls is relatively standardised:

> if they are from a dairy breed, they are weaned during the first month of their life and are then given a milk replacement, plus hay or concentrate, for three months; if they are from a beef breed they are weaned after spending 8 months with their dam at, pasture,

> subsequently, three quarters of the young bulls produced in France are given feed which includes forage maize (the whole plant). This is a very energy-rich feedstuff, rich in carbohydrates but poor in proteins, and it is therefore supplemented with protein in the form of grain, as well as oil cake (e.g. soy-bean cake).

Variations in feed are related to what is available locally.
In the north of France, which is a sugar beet producing area, or in some parts of Italy, dried or compacted sugar beet pulp (a by-product of the sugar industry) replaces maize, since it is more economical. In other regions, maize silage may be replaced by sorghum silage, alfalfa, and in some areas, by rolled grain.

In Italy, cereal straw, a rare commodity, is reserved exclusively for feed. For bedding, producers use maize or sorghum stalks, or rice bran (the husks of the rice).

Other by-products can be used, such as molasses (from the sugar industry), citrus pulp, potatoes which are unfit for human consumption, rape, sunflower seed or soy-bean cake, and brewers’ grains.

A sample feed ration for young bulls and heifers from beef breeds:

How a ruminant’s stomach works

The calf is not a ruminant when it is born; it does not ruminate as long it is being fed on milk. It begins to ruminate, at about 3 months, when it first takes in solid food.

The cow has four stomachs which enable it to ruminate
Rumination is the first stage of feeding, not only for cattle, but also for many other wild or domesticated ruminants, such as deer, zebu, buffalo, sheep, goats, mouflons, etc. When grazing, cattle ruminate from 8 to 12 hours per day. Rumination is a slow process. It can be broken down into different stages during which the food goes back and forth between the mouth and the first of the cow’s four stomachs:
> the first stomach, or rumen,
> the second stomach, or reticulum,
> the third stomach, or omasum,
> the fourth or true stomach, or abomasum.

















Rumination: the cow’s version of a takeaway meal
In order for rumination to begin, the cow first has to feed. When it grazes, it doesn’t really chew the grass, but rather swallows fairly long blades of grass whole. The grass goes down the oesophagus and into the second stomach, from whence it goes straight into the first stomach (about once every minute).







Once the cow has grazed a large quantity of grass, it quietly lies down. This is when true rumination begins. The second stomach contracts in synchronization with the oesophagus, and the long blades of grass are sent back up to the mouth from the first stomach. Once back in the mouth, the food is chewed for a long time.

The chewing reduces the size of the bits of grass. During this stage, a large quantity of saliva is mixed up with the grass: a cow that chews from 6 to 8 hours per day produces from 160 to 180 litres of saliva.

Once the small bits of grass have been well mashed up they return to the first stomach. There, microorganisms start to break down and digest the grass.

This intense bacterial activity causes fermentation. It is a continuous process, but nevertheless, a particular blade of grass can stay in the rumen for as much as 24 to 48 hours, during which time it is broken down by microorganisms. The fermentation produces volatile substances which cross through the wall of the first stomach and are used as a source of energy by the cow’s organs. They also help to produce milk.

The fermentation produces over 1 000 litres of gas per day. Only food which has been very finely mashed up into pulp goes into the next compartments, the third stomach and the fourth stomach.

Rumination means that cows don’t have to spend the whole day in the field chewing grass. On the contrary, they can spend as little time as necessary grazing, and store the grass in their first stomach. They can then move off to a sheltered spot and start chewing the grass again. Rumination enables them to reduce the amount of time they spend on grassland, where they are out in the open and exposed not only to the sun but also to predators. It shouldn’t be forgotten that cows were only domesticated relatively recently. Before that there were no farmers to protect their wild ancestors from attack by carnivores.

The third stomach starts to retrieve certain nutrients
In the third stomach, the cow absorbs a certain number of substances present in the mash of grass and microorganisms: water, sodium, phosphorus and other volatile substances. The sodium and the phosphorus are taken up by the blood and return to the first stomach via the saliva.

NOTA: Little slits in the third stomach, which are spaced at very precise intervals, mean that it works as a kind of filter: large bits of grass cannot get through. Only particles which are less than 2 mm long can get through the third stomach: this regulates intestinal transit, and prepares the cow’s food for true digestion, which takes place in the fourth stomach.

The fourth stomach uses acid for digestion
The fourth stomach secretes hydrochloric acid and a large number of digestive enzymes, just like the stomachs of non-ruminant animals (dogs, pigs, humans, etc).

NOTA: The fourth stomach digests most fats (lipids) and any plant proteins which were not fermented in the first stomach.
It also digests the proteins that bacteria produced in the first stomach. This represents 0.5 to 2.5 kg of protein per day, all produced from grass.

At the end of this long process the food no longer bears any resemblance to grass. The food now passes down the small and large intestines, where digestion continues thanks to substances secreted by the gallbladder, the pancreas, etc. But that’s another story!