Feeding for reproduction and growth

The period of pregnancy and lactation places particular nutritional demands on the doe's body, resulting in special nutritional requirements. Young kittens likewise are growing at a phenomenal rate and to achieve their potential, nutritional needs must be met. This applies to the quality and quantity of the doe's milk as well as the food given to weanlings.

A word about pregnant does

It is not necessary to make massive adjustments to a pregnant doe's diet providing that her normal diet is of good quality. There are some studies that suggest protein requirements for rats during pregnancy are higher than for a non-pregnant adult, though not a high as during lactation and early growth. It is probably helpful to feed pregant does a little extra protein and some green leafy vegetables and herbs in the daily diet. Other than this they can continue on their normal diet and just increase quantities slightly as the pregnancy progresses.

It is important to note that if the pregnant doe is a kitten herself her requirements for growth are already high - so normal diet should be high in protein, calcium, phosphorus, vitamins and calories. Hence the above still applies, normal diet in increasing quantitiy plus extra protein and greens.

Tail development as a measure of nutritional status

It is not fully understood exactly how tail development reflects nutritional status but I am convinced that it does. Even the meaty tails of large stud bucks sometimes become wasted and square in the decline of illness and old age. Under fed kittens seem to have square tails. Kittens going through a steep growth spurt sometimes get a squarish edge to their tails, that then reverts to beautiful roundness as they slow down into adulthood. I am convinced that tails can be a good overall indicator of the nutritional status of a rat throughout their lives and can be 'read' by the experienced breeder.

Fat does tend to have more birthing problems so efforts should be made to avoid overfeeding.

Principles of feeding lactating does and weanling kittens

Nursing does require a diet that is rich in protein, carbohydrate, minerals (especially calcium, magnesium and phosphorus) and vitamins. It is important that a nursing doe is given the necessary nutrition to enable her to cope with the high demands of her kittens, otherwise she will raid her own skeleton and body tissues in an effort to supply her offspring. Nursing does require between two and four times the normal amount of protein when they are lactating. Digestible protein (as opposed to crude protein) is relatively easy for a rat to absorb. Organic calcium, on the other hand, needs other vitamins and minerals to enable the rat to absorb it - notably magnesium and vitamin D. Another essential mineral for growing bones is phosphorus but, as it occurs naturally in the cereals and grain that they eat as part of their staple diet, we do not need to worry about supplementing it, as a lactating doe would simply increase the amount she would normally eat. A lactating doe may pass up to 200 mg of calcium and 140 mg of phosphorus into the milk in one day. Leafy green vegetables supply these minerals in the most accessible form.

I am constantly reviewing my own feeding programme for lactating does and their litters, and rely heavily on fresh foods. I make a constant provision of a high quality grain mix (based on my normal rat diet but with additions to increase the protein/calorie content. Along side this (and making up about 50% of the overall diet) I feed large quantities of high quality fresh foods.

My current dry mix

• Mixed straights (3 parts flaked barley, 2 parts micronised soya, one part rolled oats, one part micronised peas, one part whole corn).
• Mixed human grade breakfast cereals, generally shredded wheat, rice cakes, puffed rice (unsugared), puffed wheat (unsugared), no addedsalt/sugar muesli.
• Dry (uncooked) pasta spirals.
• Burns kibble.
• Dr Squiggles insectiverous feast
• Dried rabbit herbs (dandelion, plaintain).
• Dried vegetable and fruit (pepper, carrot, elderberry).
• Seeds (hemp, flax)

Fresh foods

• Daily (large) portion of curly kale, clover or young dandelion leaves.
• Broccoli.
• Carrot.
• Chicken (whole wings and drumsticks provide the higher protein flesh and the benefits of mineral rich bones to chew on)
• Egg (scrambled, boiled chopped, mixed into porridge or soaked into wholemeal bread and cooked in a touch of olive oil).
• Fish, shellfish (cooked and tinned [lowest salt] acceptable).
• Lactol (bottled or made into porridge or over wholemeal bread).
• Dr squiggles insectiverous feast.
• Nature Diet moist puppy food.
• Banana and avocado pear.
• Liver cake.

As the babies grow I add in more high carbohydrate foods such as cooked wholegrain rice, bulgar wheat, cooked barley, lentils, legumes, pasta, noodles, potato, sweet potato, cous cous alongside the foods listed above.

I try to give at least one protein and carbohydrate meal a day and curly kale (or substitute) every day. The rest is in rotation depending on what is available.

Supplements

There are a number of supplements that are suitable and useful for growing families. Some of these are:

• Calcivet - saturated liquid calcium/magnesium supplement with vitamin D
• Seaweed powder - benefits fertility, muscle, bone and tooth formation, coat and skin condition
• Daily Essentials or Essentials Plus - general multivitamin/mineral supplements

This is a time of rapid (but gradually decreasing) growth, and adequate diet is necessary for a rat to fulfil its physical potential and remain in good health. Growth requires protein for the development of body tissue, calories for energy (from carbohydrate and fat) and vitamins and minerals (notably calcium, magnesium and phosphorus) for healthy bone and tissue production. Once growth slows down (usually around 6 to 7 weeks), it is obviously not necessary to give the same quantities of these nutrients, and failure to change feeding patterns can result in obesity and ill health later in life.

I tend to feed as much as they will take up to about 6 to 7 weeks of age and then decrease the fresh element significantly (giving smaller volumes maybe every other day and slowly decreasing, so that by 3 months they are on a standard adult diet with the main fresh element being vegetables. I am aiming at good nutrition but slow growth into adulthood, as this is likely to give the best results in terms of lifespan. Underfeeding rats in the first few weeks of life can lead to health issues and shortened lifespan regardless of later nutrition. But after about 7-8 weeks of age there are benefits to health and longevity in limiting food available rather than continuing the ad lib, feeding to maximum growth approach.

Weaning period

This is the period from about 14 to 18 days onwards, when kittens first begin to take food other than their mother's milk. Rat kittens are normally fully weaned between 4 and 5 weeks, but continue to benefit from having some 'weaning diet' for some weeks after this. Weaning foods tend to be soft, moist and initially mimic the milky diet the kittens are used to (see list above).

A word on quantities

It cannot be over emphasised how much food a young, growing family will need. Kittens will remain undernourished even if they are given an excellent diet, unless they are given enough of it. As the doe will have eaten a number of placentas and tidied up after the birth she will often eat very little in the first 24 hours post delivery. After this she will begin to eat in earnest and her appetite will increase to match the increasing amount of milk that she is producing for her offspring. This will reach a maximum somewhere around 3 weeks post delivery. After this the volume of food eaten by the babies gradually increases, and the demands of lactation gradually decrease. But the volume of food eaten by the growing family as a whole will continue to increase.

As a general rule the family should have food available to them at all times. If you are returning to empty bowls you need to increase the volume given or the frequency of meals (2 or 3 per day). Whether or not their nutritional requirements are being met is fairly easy to assess, simply by watching the progress of both doe and kittens. Most mothers lose a little weight between the second and fourth weeks when the demands of lactation are at their highest. Equally most does return to excellent condition by the time the babies go to their homes at 6-8 weeks. The kittens should be 'substantial' and well covered though not fat, their tails round and increasingly thick. Generally those who have been fed to their requirements will have come into their shiny 'adult' coats by 5 and a half to 6 and a half weeks (rate of moulting is affected by nutrition).

Conclusion

Feeding a doe and her young kittens well is hard work, but essential to their future well being. There may be different reasons (such as poor lactation) why a particular litter may not achieve their full potential, but these are not the norm. It is perfectly possible with excellent nutrition to raise repeated generations of complete litters while continuing to improve type. What is probably more difficult is to find the middle ground with feeding growing rats, so that they fulfil their potential, but do so slowly over time, thus maximising health an lifespan potential too.