The rat is a natural forager; finding its food wherever and whenever it can. Historically, we have fed our small, caged animals out of food dishes, but only by scatter feeding rats, can we allow them to mimic this natural foraging behaviour. Being a true omnivore and opportunistic by nature, means that despite their neophobic tendencies (reluctance to try new things) – rats will eat almost anything.
A large part of a wild rat’s ‘day’ is given over to seeking, finding, stashing and eating a myriad of different food-items, from roots and leaves, to insects and even faeces. Rats will get their nutrition where they can, but it is well documented that they can often go to great lengths to get their hands on something special. Rats will steal eggs from nests, dive for molluscs, raid stables for stored grain and scavenge for food waste in the rubbish left lying around our city streets. The desire to search for food is an instinct driven by thousands of years of evolution, which has created a small mammal capable of thriving in almost any environment, eating almost any combination of available food sources. Even in a domesticated rat, this instinct remains strong, and creating an in-cage environment that encourages foraging is both enriching and supportive of natural behaviour.
What is scatter feeding?
Scatter feeding refers to the act of spreading the rats’ daily allowance of food around the cage; hiding it under cage litter, in enrichment feeders or small cardboard boxes. When you are scatter feeding rats, there is no requirement for a food bowl other than for fresh foods, but these too can often be scattered. In many ways, the more imaginative the placement of food, the more enriching the experience of finding it can be for the rat.
Food from the rat’s perspective
A rat is in some ways very human-like in its approach to food. Rats don’t just eat functionally – though in times of scarcity they will eat whatever is available – they also derive pleasure from eating. Rats have been shown to emit the same high pitched (above our natural range) pleasure noises when anticipating a delicious treat, as when being tickled and played with.
They often have strong preferences in relation to food, which are based on their own, their mother’s and their colony members’ past snacking experiences.
A rat can make a decision based on whether or not they know something, driven by the likelihood of getting a really desirable (high-value) food reward.
However, their overwhelming pattern of feeding behaviour – whether wild or domesticated – is foraging and sampling. A good chunk of their time is spent looking for food and then sampling anything unknown, in small amounts. This is done in order to establish physiological consequences – is the food safe? Desirable and undesirable food preferences can also be learned as an infant and weanling from the mother, and throughout life from other group members Rats in a colony will avoid the food that a scouting rat smells of, should that rat get sick.
Scatter feeding rats – why?
Imagine for a moment that you are a rat. You are designed to forage and have learned that some foods are both delicious and safe. Imagine your joy when digging about in one corner of your environment, you discover a really tasty morsel.
Scatter feeding rats, not only relieves the boredom that can arise from in-cage living, but it provides for the expression of natural behaviours (such as searching, digging, problem solving, foraging and sampling). Add to this the enrichment of the emotional life of the rat and it’s clear that from the rat’s perspective, this is a preferable way to feed.
Happily, there are also real advantages for us humans, when it comes to managing the different needs of individual rats within one cage group.
Managing the nutrition of a number of rats within a colony hierarchy, when feeding from a bowl, can be difficult. At best, there can be wide discrepancies in the rats’ weights, and at worse, a very low ranking rat can be bullied into not eating enough to maintain his health and well-being.
Scatter feeding rats helps to balance out the needs of each individual. A greedy rat can no longer hog the food bowl, and a dominant rat – distracted by his own search for the ‘best bits’ – is more likely to leave a low ranking rat in peace to feed. In the process of scatter feeding rats, food is distributed around the cage, on different levels and to some extent, hidden in more challenging places. With a little planning, it is easy to offer growing kittens food that larger adults cannot easily reach or gain access to.
Scatter feeding rats, also helps to make food last, especially where the rats have to work to access the food. This is preferable to a group of rats descending on a bowl at feeding time and leaving only scraps within a matter of minutes.
Stashing food is a natural rat behaviour and scatter feeding allows this to happen without a rat jeopardizing their share of the food. When competing around a food bowl, an efficient feeder will remain at the bowl and not leave to stash, thus consuming a larger proportion of the available food than a rat who leaves to stash.
Rats who are scatter fed exercise their minds and bodies in their search for food around the cage. This is one reason why it is a good idea to be imaginative, rather than just placing the food in the same area every day. This daily forage for food aids metal and physical fitness and well-being.
Scatter feeding rats – how?
At its simplest, scatter feeding is taking the food you would normally place into the food dish each day and spreading it around the cage. The more effort you take about making food accessibility a challenge, the better! Only very old and sick rats need food to be readily available, and while these rats will still usually enjoy a rummage in the cage litter for a tasty morsel, their nutrition should be offered in a bowl for the main part.
Trust your rats to do what they have evolved to do. Forage. Caged rats can become lazy, but that doesn’t mean that they can’t revert to foraging if the opportunity is presented to them. Don’t be tempted to overfeed in case your rats don’t find every piece of food. This will lead to selective feeding (eating only the most preferred foods), wastage and the rats becoming overweight.
When scatter feeding rats, your aim is to find very little uneaten food around the cage when you come to clean out. Monitoring this waste food alongside the condition and weight of your rats (visually), will help you to get the amounts right. When you feed fresh food (unless your rats are on an entirely fresh food diet), only give about a dessert spoonful, per rat, per day and remove any uneaten fresh food after 12 – 24 hours depending on the ambient temperature.
I’ll be looking at some enrichment ideas for feeding in a future post
Behaviour Components in the Feeding of Wild and Laboratory Rats S. A. Barnett Behaviour Vol. 9, No. 1 (1956), pp. 24-43
Dot Paul, University of Georgia. “Rats Capable Of Reflecting On Mental Processes.” ScienceDaily. ScienceDaily, 9 March 2007.
Individual differences in anticipatory activity to food rewards predict cue-induced appetitive 50-kHz calls in rats.