MILK REPLACER for RATS
About Rat Milk:
Different species of mammals produce milks of different composition in order to nourish their young:
Species
Solids
(g/L)
119
221
227
Cow
Rat
Dog
Protein
(% Solids)
25.6
36.7
33.2
Fat
(% Solids)
29.9
39.8
41.9
Lactose
(% Solids)
38.7
17.2
16.7
Metabolisable
Energy (kJ/L)
2620
5280
5440
Rat milk is characterised by relatively high solids content, elevated fat levels and low amounts of lactose1.
Rat milk has about twice the energy per litre than that of ordinary cow’s milk. The high amount of lactose
and low energy value of cow’s milk make it an unsuitable substitute for hand rearing rats.
However, due to limited demand, it is not commercially practical to produce a milk replacer specifically for
rats. We therefore recommend to use Wombaroo Dog Milk Replacer as a suitable substitute. As can be
seen in the table above, rat milk is similar to dog milk in composition and energy. Domestic rats as well as
native species (Bush rats, Water Rats) have been successfully reared using this milk replacer.
Typical Composition per Litre of Prepared Wombaroo Dog Milk Replacer
Protein
Fat
Carbohydrate
Energy (ME)
Vitamin A
Vitamin D3
Vitamin E
Vitamin K
74g
89g
32g
5100kJ
400µg
15µg
15mg
2mg
Choline
Inositol
Vitamin C
Thiamine
Riboflavin
Pyridoxine
Nicotinamide
Pantothenic Acid
110mg
80mg
30mg
9mg
3mg
3mg
35mg
15mg
Folic Acid
Biotin
Vitamin B12
Taurine
Calcium
Phosphorus
Potassium
Sodium
1mg
110µg
30µg
500mg
3g
2g
1g
450mg
Magnesium
Iron
Zinc
Manganese
Copper
Iodine
Selenium
100mg
6mg
4mg
2mg
1mg
130µg
30µg
Ingredients: Whey protein, caseins, whole milk solids, taurine, vegetable oils, omega-3 and omega-6 fatty
acids, vitamins and minerals.
Pack Size: 215g, 1kg, 5kg, 10kg & 20kg.
Hand Rearing:
Success in hand-rearing young rats (pups) greatly improves if they receive colostrum at birth. Pups that
don’t get colostrum from the mother should be fed Impact Colostrum Supplement in the first 48 hours of
life. Commence feeding Wombaroo Dog Milk Replacer from 12 hours of age onwards, after the initial
feeds of colostrum. Keep pups in a clean, draught-free environment at an appropriate temperature for age
(see table below). Supplemental heat may be provided by using a Cosy Heat PadTM.
Age of Rat Pup
1-3 days
4-14 days
15-21 days
21+ Days
Housing Temperature
32-35°C
26-32°C
24-26°C
21-24°C
Wombaroo Food Products ph (08) 8391 1713 www.wombaroo.com.au
Updated 30/05/13
Making up Milk: Add 20g of powder to 75ml of preboiled warm water (makes approximately 90ml of
milk). Add about half the water to the powder first and mix to a paste. Then make up with the remaining
water and mix thoroughly. Other volumes of milk can be made up by scaling up or down the above
quantities. Avoid making up very small quantities of milk as this becomes inaccurate to measure out and
difficult to mix. Prepared milk can be stored in a refrigerator for a day or frozen for up to 2 weeks. Small
quantities can be frozen in ice cubes trays, so that the required daily feed volumes can easily be thawed
out. Do not re-freeze thawed milk.
Feeding: Warm milk to about 35o C. Feed from a dropper or syringe every 2 hours for the first 3 days,
reducing this to every 3 hours by the end of the first week. Stimulate pups to defecate and urinate after
each feed for at least the first 7 days. During the second week reduce feeding to 4 hourly intervals.
Encourage pups to lap from a shallow bowl once their eyes are open and voluntary bowel motions begin
(at about 14 days). To avoid dehydration during periods of hot weather provide drinks of pre-boiled water
between feeds. Always offer pups drinking water once their eyes are open and they become mobile.
Consult your veterinarian or experienced carer for particular advice about hand rearing rats.
Growth: Body weight of domestic rat pups should increase by about 2 to 3g per day. It is important to
weigh pups regularly with an accurate set of scales to verify weight gains and determine the volume of milk
to feed. Overfeeding milk can cause diarrhoea so feed the suggested volumes in our tables.
Guide to Feeding (Domestic Rats) – growth rates may vary according to breed or species (eg native
species)
Age
Body Weight
Feed Volume
Age
(days)
(g)
(ml/day)
(days)
Birth
5
2.5
10
2
9
4.0
12
4
14
5.5
15
6
18
6.7
18
8
22
7.7
21
* Feed volume now depends on quantity of solid food eaten
Body Weight
(g)
26
31
40
50
60
Feed Volume
(ml/day)
8.8
10
12
14
16*
Weaning: When rats are about 14 days old they should show interest in solid food. To entice them to eat
solids offer a small portion of rat cubes soaked in Wombaroo. Once they start to eat solid food continue to
increase the solids and reduce the milk in their diet until they are fully weaned at about 21 to 28 days.
References:
1. Oftedal, I.T.&S.J.Iverson. 1995. Comparative analysis of non-human milks. In “Handbook of Milk Composition”.
Academic Press
2. Peters, R. H. 1993. “The Ecological Implications of Body Size”. Cambridge University Press
3. Quesenberry, K.E. and Carpenter, J.W. 2004. Ferrets, Rabbits and Rodents Clinical Medicene and Surgery. 2nd
Ed. Saunders Press.
4. Keeble, E. and Meredith, A. (editors). 2009. BSAVA Manual of Rodents and Ferrets. British Small Animal
Veterinary Association.
Wombaroo Food Products ph (08) 8391 1713 www.wombaroo.com.au
Updated 30/05/13