This is a typical example of how you might expect a healthy baby opossum to grow:
The side figures indicates weight in grams.
Before we go on to diet, I want to pass along some information about distilled water. Distilled water has been the only water recommended for use in possums (of any age). The following information brings to light some worrisome facts about the long term use of distilled water. I use bottled spring water now. You could also use water that has gone through reverse-osmosis.
Distilled water is known as "empty water". All good minerals, all bacteria
and pathogens of all kinds do not exist in the distilled water that is a
result of steamed distilled water. When your animal consumes distilled
water, the water molecules will attach themselves to minerals and electrolytes
in the body.
****When your pet urinates all of these good items go OUT of the
When your animal is in need of getting toxins out of its body, distilled water is a
good drink because it aids de-toxing. The empty molecules attach themselves to
toxins and help clean the filtering systems in the body.
**** It should NOT however, be used long term.
REMEMBER TO HYDRATE FIRST!!
One thing to ALWAYS remember is to rehydrate any babies you take in before placing them on formula! There are a number of ways to do this:
Make solutions out of the following:
Best: 1 part bottled spring water to 1 part Ringers.
Apple juice: 1 part juice to 5 parts bottled spring water.
Home Recipe: 1 cup bottled spring water, 1/4 tsp salt, tsp sugar.
DO NOT USE ELECTROLYTE SOLUTIONS CONTAINING ASPERTAME !!
There are several commercial hydrating solutions sold in grocery stores that do not contain aspertame, so make sure you read the labels before purchasing.
Depending on the condition of the babies, give hydrating fluids for 12-24 hours, and then commence giving formula. I begin giving 1/4 strength formula for the first 2-3 feedings, then 1/2 strength, and then full strength to give their systems time to adjust.
IMPORTANT! Formula's should be prepared as follows: 1 part formula to 2 parts spring water. For infants under 30 grams mix it 1 part powdered formula to 5 parts bottled spring water. If the infants are extremely small, and came in dehydrated, mix 1 part powdered formula to 10 parts bottled spring water.
Ok, before I get on the different diets rehabbers use, I must say this: NEVER, EVER use cow's milk or goats milk!!! They cannot tolerate it!!
WARNING!! Apparently there might be some connection to liver failure in young orphaned babies who have been nursing on a dead mother. Another rehabber I believe lost an entire litter to liver failure, who had been nursing off a dead mama. I am waiting to hear the reports regarding this matter. I am wondering if Milk Thistle might work under these circumstances, but of course this herb is not indicated UNLESS there is a proven problem with the liver. To use this herb indicriminantly could prove dangerous. Has anyone else heard anything about liver failure caused by bad milk? If so, please contact me: firstname.lastname@example.org
Diet is, and may always be, a controversial subject among rehabbers. I am just here to list examples of what has been used by different people, some with reportedly, long-term equal success.
One thing you should try and do is use a cat food that is very similar to the following analysis:
Vitamin A 10,000 IU/kg
****It is recommended until further studies are in, to avoid foods that contain soy or corn.
The Modified Jurgelski Diet: JUST SAY NO! This is a dangerous diet some organizations and indiviuals suggest.
HOW MUCH DO I FEED??:
Here are approximate amounts of formula to be given babies based on their weight in grams:
10 grams: .50 cc's every 2-3 hours
15 grams: .75 cc's every 2-3 hours
20 grams: 1.00 cc every 2-3 hours
25 grams: 1.25 cc's every 2-3 hours
30 grams: 1.50 cc's every 2-3 hours
35 grams: 1.75 cc's every 2-3 hours
40 grams: 2.00 cc's every 4 hours
45 grams: 2.25 cc's every 4 hours
50 grams: 2.25 cc's every 4 hours
55 grams: 2.75 cc's every 4 hours
60 grams: 3.00 cc's every 6 hours
65 grams: 3.25 cc's every 6 hours
70 grams: 3.50 cc's every 6 hours
75 grams: 3.75 cc's every 6 hours
80 grams: 4.00 cc's every 6 hours
85 grams: 4.25 cc's every 6 hours
90 grams: 4.50 cc's every 6 hours
95 grams: 4.75 cc's every 6 hours
100 grams: 5.00 cc's every 6 hours
At around 55-60 grams your babies should be eating on their own. Be ready, for they will make a huge mess! They will spill their formula, wear their formula and after they are done, will happily lick it off themselves and each other while grooming.
A very handy little item to have on hand are disposable pipettes (I recommend the 3ml (3cc) size). They work so well feeding tiny babies, are cheap to buy, and you just use and toss. I prefer them over syringes.
Photo By: Shonda Statini
Craft stores often carry pipettes, but they are so much cheaper online. Here are a couple resources for you:
Disposable 3ml pipettes
(Look under fish supplies)
ESBILAC: Puppy Replacement Milk (powdered). This formula must be embelished with 200 mg calcium, 1/2 of a large cooked egg yolk, 1/2 of a 7.5 gram tab of nutritional brewers yeast, 2 teaspoons of unsweetened apple juice and a 2-3 inch line of Nutrical per cup of prepared formula. Use only bottled spring water to make this formula, or any other, as well as for drinking water.
Milk Matrix 30/55 and 33/40 (powdered):
****Be sure to add 200 mg of calcium to each cup of prepared formula and a 2-3 inch line of Nutrical.
****Be sure to add 200 mg of calcium to each cup of prepared formula and a 2-3 inch line of Nutrical.
FOX VALLEY: (powdered)
I have not used this formula as of yet. This company makes formula for many different species of wildlife. I have heard mostly good reports about their formula from other rehabbers. Sold online only.
As far as I know, this product is sold online only.I have never tried this formula, but a few rehabbers have given it the thumbs up. The company claims this formula is based on the needs of all marsupials. To read about this product, go to the following websites:
KMR: Kitten Replacement Milk (powdered).
KMR is sold in pet stores as well as online. ****Be sure to add 200mg of calcium and a 2-3 inch line of Nutrical to each cup of prepared formula.
**** Usually between 40-50 grams babies are able to lap formula from a shallow dish. They will make a mess, but they need to learn this very important skill!!
Once your babies reach a certain age, (about 70 grams) you will need to begin incorporating less formula and serving them semi-solid foods. You can make a nice mash for possums up to about 100 grams out of softened or ground up adult cat chow kibble, vegetables and yogurt. If you really want to make things easy, use baby food vegetables.....just make sure there is no meat or onions in it! Use vegetables low in Vitamin A such as peas, squash and green beans. Take 1 cup cat chow, 1 cup pureed vegetables, and 1/4 cup plain yogurt and blend until very smooth. This too can be frozen into cube trays and thawed as needed. I have always just plopped a few spoonfuls in a shallow dish (depending on how many babies there are) and let them eat until they are full. They will stop when they have had enough.
To feed babies who are between roughly
feed a mix of 1 cup formula (already mixed with water), 2 tablespoons of the cat chow mix recipe above, 2 tablespoons baby food fruit and serve in a shallow bowl. They will make a complete mess, but that is just part of the process! :)
At 100-200 grams
mix of 1 cup formula, 3/4 cup cat chow mix, 1/3 cup fruit, and 1 tsp of protein. Blend well and serve.
At 200 grams-1 pound, feed a mix of 1/4 cup formula, 1 3/4 cup cat chow mix, 1/2 cup fruit and 2 1/2 tsp of protein.
After the possums reach 1 pound, you should no longer feed extra formula. Just mix up 3 1/2 cups of the cat chow mix, 2/3 cup fruit, and 1/3 cup protein.
WHAT DO YOU MEAN BY PROTEIN??
Protein is an important factor in a opossums diet, however, too much can cause serious issues such as MBD (Metabolic Bone Disease), so you must be very cautious about how much you serve to an opossum of any age.
To make a good protein mix try this recipe:
2 large cooked eggs (you can hard boil these and puree with the rest of this mix, shell and all)
1 cup plain yogurt (with live cultures)
1/4 cup sardines (salt-free and packed in water) or salmon.
1/4 cup chicken liver or hearts (cooked)
Blend to a smooth consistency, freeze
in ice cube trays and pop out what you need at each feeding. I usually freeze my protein mix seperately from the cat chow mix because if you have babies at different stages of diet, you will not be
to feed them the same mix. If you are really industrious, you can make larger
of each stage, mark them clearly, and freeze seperately. It will save you time
in the long run!
BEFORE YOU RELEASE:
At least a couple weeks before I release our babies, I wean them off the pureed food
and onto dry kibble, diced raw vegetables, chunks of protein and a bite or two of
fruit. They need to get used to useing those teeth. Their food is not going to be
pureed for them out in the wild! I also get them used to catching and eating live
insects and worms.
HOW OLD IS THIS OPOSSUM?
Something to go by to tell how old babies are:
10grams-pink -no hair embryo look.
25grams-begins to get hair-eyes not open - feed every 2-3 hrs. 1.25 cc formula
35grams- fully furred should be lapping by now with eyes fully open feed every 2-3 hrs. 1.75cc formula.
After this you can feed every 4-5 hours.
Below are some pictures that dipict "appx" ages:
Very young neonates, just a few days old.
Photo By: Laura Ledet
Appx 1 month old: Notice the skin pigmentation beginning to change.
Photo By: Racquel Ringling
The composition of milk samples collected from captive opossums (Didelphis
virginiana) was determined at various intervals during lactation. The milk
solids increased from 9% at week one to a maximum of 34% at 11 weeks
post-partum. There were changes in the relative proportions of protein, lipid
and carbohydrate at different stages of lactation. Lipid represented the
greatest fraction of the solids except for a period at mid-lactation when there
was a peak in protein concentration. The concentrations of sodium, potassium and
magnesium were relatively constant, 41 +/- 4, 35 +/- 11 and 9.2 +/- 1.6 mmol
respectively, although calcium increased from 13 +/- 5 mmol at week one to a
peak of 112 +/- 35 mmol at 9 weeks.
Nutri-Cal vs VitaCal:
These products are used in formulas and also as a quick way to boost caloric intake. Here is a comparison between two of the most well known brands.