An important part of any rat’s diet is fresh fruit and vegetables, these provide the extra vitamins and minerals that your rats food does not provide, which is particularly important when feeding a home made mix As with a rats main food it is important to get this in the right balance and proportions as over feeding can encourage your rat to become fat or unbalance the nutrition it's getting from its main food. Even overfeeding the healthy stuff can lead to problems such as diahoria. When feeding fresh food a good amount to keep in mind is around 20%. This still allows the dry mix to make up the majority of the diet, and so help maintain the balanced diet and keep the rats able to munch most of the day but it also gives a good amount of fresh minerals and vitamins which are difficult to beat.
This is one of the most useful fresh foods to feed your rat and is a very important part of a balanced diet and a happy healthy pet. The key thing when feeding vegetable is not to feed too much too soon. If your rats are not used to eating vegetables daily then they can potentially get diahoria from eating too much straight away. Start small and feed a tiny amount building up to around 15-20% (by weight, including any fruit) of their diet. The best way to feed vegetables is to feed them raw and in season as that's when they contain the most vitamins and minerals. Ideally locally sourced organic products should be used but this isn't always practical where you live. A good option can be to grow your own which isn’t as difficult as it sounds.
- Dark green leafy vegetables
This includes Cabbage, Kale, Spinach, Spring Greens, Pak(Bok) Choy, broccoli (not exactly leafy but the same principle) and similar vegetables. They are rich in vitamins and minerals and antioxidants and are an excellent addition to your pet’s diet. Of these the most useful is Kale as it has the highest levels of desirable mineral, however a bit of variety is good for the rats. Broccoli is another good one as it is an anticarconogen (reduces the risk of cancer) and full of goodness.
Many kitchen herbs are good for your rats, and also make them smell good. Basil, mint, sage, parsley and fennel among others.
- Root vegetables
This includes Carrots, Potatoes, Swedes, Parsnips and other roots. Carrot is by far the most useful of these vegetables as it's so full of goodness, however this is quite easy to give too much of resulting in quite loose stools and not a pleasant smell so only feed a small amount. The others are fine to be fed though not as useful.
Warning – green potatoes should not be fed; some people are wary about feeding any raw potato and prefer to feed it cooked.
- Watery vegetables
These include cucumber, lettuce, celery and similar vegetables. The key thing being their water content. These vegetables can be useful in summer or when travelling or showing your pet as they provide a good source of moisture in an environment where your pet may not be drinking enough to keep them well hydrated. The most useful of these is cucumber. It is worth limiting the amount of lettuce fed as it does cause loose stools very easily, it also has a soporific effect on rabbits (drugs them) though there is little evidence to confirm this happens in rats. Celery is another to be cautious of in any reasonable quantity as it has very little nutritional value and is know to be mildly carcinogenic (increases the likely hood of cancer).
- Other useful vegetables
This includes peas, sweetcorn, corn on the cob, mushrooms etc. Peas are a great healthy rat treat and can even be fed frozen which makes them an ideal summer treat, one of the best way to serve frozen peas is in a dish of shallow water for some serious pea fishing. Sweetcorn can be used in a similar manner and is much loved by rats. Corn on the cob (especially in its wrappings) is a good challenge for rats, hang it in the cage or tied to the bars to make them work for it, don't feed too often as there's a lot of corn and it can lead to diahoria. The dried corn on the cob is also a nice treat but as dried corn is included in most rat mixes it's worth limiting this as if an animal gets too much of one grain there diet suffers (variety is the key). Mushrooms contain high levels of copper, a mineral that can be deficient in some homemade mixes (shop bought mixes are generally supplemented).
Fruit are a great treat for your rats though in moderation. It is high in sugar which isn't good for ratty teeth however fructose (rather than the normal sugar glucose) is harder to digest so much better. If you feed fruit it needs to be in moderation, around once or twice a week and rarely every day. Some fruits are particularly useful and can have benefits to the overall health of your rats. The following groups attempt to cover the main fruit types
These include strawberries, blue berries, grapes (red are the better of the two), black berries, blackcurrants, raspberries and so on and it is also useful to include pomegranate in this list as its properties are similar. These contain high levels of antioxidants which make them a very desirable food. Antioxidants can reduce the risk of cancer and boost the immune system so these make an excellent food stuff for your rats. Be warned though, many a rat owner has come close to panic after feeding berries the night before and coming into a scene of chaos with an apparent blood soaked cage only to remember (normally after checking every rat in the cage) that they fed berries the night before.
- Citrus Fruit
These include oranges, lemon, lime, mango, papaya, grapefruit etc. This groups of fruits are fine to be fed to female rats however you should be cautious before feeding them to male rats, especially the juice and peel. The peel contains delimosines which has been linked to testicular cancer in rats and while the fruit has not been proven to cause harm it is probably worth avoiding, there are many other good fruits to use. Commercially available juice should also be avoided as it often contains some processed peel to add to the flavour. The science behind this is not so robust with papaya and mango but it's probably best to avoid this with males.
- Watery Fruit
These include; Apple, pear, grapes, melon, berries and similar fruit with high water content. These are useful in a similar way to watery veg however they have an additional bonus that the sugar content in the juice can help flagging rats by giving them a boost of energy, they are also generally more palatable to rats and so encourage them to eat them. An interesting note on melons is that the seeds, once scooped out and rinsed to remove the pulp, can be left to dry in the sun and make a very popular rat treat with similar properties to pumpkin seeds but smaller, the fact they come complete with shells mean you have time to give all the rats in a cage one without them finishing the treat too soon.
- High Calorie Fruits
These include Banana and Avocado. Both these fruits have a particularly high fat content (avocado being the higher of the two), whilst being soft, highly palatable and easy to eat. This makes them very useful for feeding to ill or convalescing rats. The additional sugar can also give them enough energy to tackle more substantial foods as it is relatively easy for their body to absorb.