Factors Affecting Feed Intake

However nutritious the feed offered to an animal is, it is of no use if the animal does not eat it. A number of factors affect the amount that an animal eats, and include: The composition of the diet The way feed is presented The individual animal and the flock or herd in which it is kept The availability of water

Diet Composition Feed Presentation Individual Animal Herd/flock Pressures Water

A number of feeds are unpalatable to livestock. Animals will avoid such feeds, and may reject the whole feed mix if they cannot select more palatable feeds from it. Feeds are sometimes unpalatable because they are toxic, but this is not always the case. If an unpalatable feed has been included in the diet because it provides a particular nutrient that is otherwise limiting in the diet, then the unpalatable feed needs to be well mixed with the rest of the feed if it is to be eaten. Feeds with strong (palatable) smells and tastes may need to be added to mask the unpalatable feed.

To some extent, livestock will select feeds that provide them with the nutrients that they need, and provided they are given a wide enough choice of feeds they will select a reasonably balanced diet. This does not happen in all situations, though, and if there is one particular feed that an animal likes, it may well eat it to excess and reject other feeds, resulting in an unbalanced diet. If that is the case, then the amount of the ‘favourite’ feed needs to be restricted so that the animal will then move on to eat other, less desirable feedstuffs.

If the livestock keeper wants to feed particular feeds to their livestock, then the diet needs to be restricted so that the animal will eat those feeds. On the other hand, with highly fibrous feeds like straws, it is better to offer large amounts of the feed (two or three times what the animal will eat) so that it can select the bits of the feed that are more palatable and digestible.

Feeds that have grown mould should not be fed to livestock. They are likely to reject them anyway, unless they have nothing else to eat, but the moulds produce toxins which can cause disease or death in the livestock.

 

Sheep and goats prefer succulent feeds (fresh grasses and leaves) to dried forages like straw. With all livestock, chopping (or in the case of poultry, grinding) the feed will also make the animals eat more. This of course assumes that there is a plentiful supply of feed, and high intakes are wanted so that animal productivity can be increased. There are many times of the year (particularly at the end of the dry season) when feed is in short supply, and it is more important then that the feed provides ‘gut fill’ so that the animal feels satisfied. Feeding forages with a higher fibre content, and in a long rather than chopped form will help with this. Some feeds are better than others at providing gut fill and indigenous knowledge is very important at selecting such feeds.

Feeds should be presented in such a way that animals are able to eat it in the way that they naturally feed. Goats browse, and so prefer a feeder that holds the feed at a height where they need to reach up to get it rather than a trough on the floor. Sheep on the other hand prefer a trough on the ground. Stale feed that has been rejected by animals (particularly once it has been trodden on and dunged on) needs to be cleared away. It won’t be eaten by livestock, and mixing fresh feed with it will only put animals off eating the fresh material.

Sheep, goats and poultry digest feed better if small amounts are offered to them at frequent intervals, rather than large amounts at once. This is not always practical, but two or three feedings a day is better than one and if concentrates are being fed to sheep and goats it is better if a small amount is fed every day (and two or three times a day rather than just once) rather than a large amount every few days.

An animal’s appetite changes as its requirement for nutrients changes. Young, growing animals have a greater appetite than adults. Lactation brings about a big increase in appetite because of the demands of milk production.

 

When other animals in the flock or herd are eating, individual animals are encouraged to eat. However, all flocks and herds have a hierarchy and while dominant animals get more than their fair share of feed offered, the more submissive animals in the flock or herd can only eat what is left. They may still be harassed and prevented from eating when others have stopped. Ensuring there is sufficient trough or feeder space so that all members of the flock or herd can eat at the same time reduces this problem, but younger and more vulnerable members (or those with particularly high requirements because of lactation) may need to be fed separately to ensure that they get the feed that they need.

 

Feed digestion needs water, and dry feeds (especially straws and stovers) are particularly hard to eat and the animal needs to be able to drink while they are eating them to help them chew and swallow them. Ideally, livestock should always have a supply of clean, fresh water. This is rarely the case, but the more often they can be provided with fresh water the healthier they will be.