Rat Café - keeping cool
Alison Campbell

Cool summer cuisine
Now that the daylight hours are longer and the weather is warmer I thought we could take a timely look at some of the nutritional issues that are pertinent to this time of year. Knowing our glorious and unpredictable climate you are probably reading this, curled up in front of the fire with a fleecy blanket, drinking cocoa… so let your imagination run to balmy, summer days…

Rats have a slightly higher normal body temperature than we do (around 37-39 degrees celsius depending on the strain, with 37.5-38 degrees C being the most commonly quoted ‘norm’). Body heat is generated by metabolism and a rat’s metabolism is fast and furious, producing a lot of heat. Depending on the environmental temperature this heat is either conserved (to keep the rat warm) or lost (to cool the rat down). The tail is the most efficient part of the rat for heat regulation, as it has a large surface area to volume ratio, is well supplied with blood vessels, and is not heavily furred. By either constricting or dilating the blood vessels within its tail a rat can change the amount of blood volume that reaches this part (from between about 0.1% to 10%) and so regulate the amount of heat lost. Even with this system rats do not cope well with high environmental temperatures, and begin to experience difficulties regulating their temperature at ambient temperatures of over about 32 degrees C (with temperatures over 38 degrees C being potentially fatal). Heat is trapped and exaggerated in particular environments such as cars, conservatories and some sheds, and special care should be taken in these situations. Heat stroke is frequently fatal in rats, and larger rats are generally more susceptible. Symptoms of over heating include:

• Lethargy
• Increasingly warm tail
• Deep pink ears
• Drooling

Every effort should be made to keep rats in a comfortable environmental temperature. To reinforce this certain foods and food techniques can be used to help maintain the rat’s normal body temperature.

Keep a spare filled water bottle in the fridge and swap this with the one on the cage every few hours, so that drinking water is chilled.

Place a shallow baking tray with a little water and a few ice cubes into the cage. Encourage the rats to paddle by dropping in a handful of frozen peas or sweetcorn.

Buy a bag of frozen mixed summer fruits, and feed them straight from the freezer.

Offer chilled cucumber, melon, watermelon and tomato and these are very high in fluid content.

Soak other vegetables and fruit (eg. carrot, apple) in water in the fridge overnight prior to feeding as this will increase the water content and chill them.

If you’re travelling with your rats:
The night before you travel feed a high carbohydrate meal, with some quality protein and vitamins and minerals, for example, cooked pasta mixed with tinned mackerel and chopped fresh kale. Soak some of your rat’s favourite fruit and vegetables in water in the fridge overnight. This can greatly increase their water content and means they are chilled when you set off (these can be kept chilled in a thermos flask for feeding later during long journeys).

On the morning of travelling feed a nourishing, sloppy meal prior to setting off such as cereal soaked in soya milk. Ensure that your rat is well hydrated prior to setting off.

If possible travel the rats in a small wire cage (such as a small, one level hamster cage) and attach a water bottle.

Cover part of the cage with a damp towel and place a ceramic tile on the floor of the cage so that the rat can lie on it if it wishes.

Make sure that foods containing fluid are available at all times.

Take a water spray and mist your rat during the journey if they seem hot.

Heat and nutrition
High environmental temperatures generally cause a decrease in metabolic rate (as there is no need to produce heat to stay warm), and sometimes a decrease in appetite.

If appetite is maintained it is easy to over feed in the summer months.

To avoid this feed extra green/red vegetables and berries, which provide excellent micronutrients without too many extra calories.