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Wild Mammal Milk Composition Studies (90+) 

(aka Mother's Milk)



Milk composition values (proximate analysis)


The tables on this page provide approximately 100 scientific studies where wild mammal milk was obtained and analyzed from lactating females. Some of these studies are included in WildAgain's Wildlife Formula Calculator, generally for the more common species that are widely rehabilitated. These tables can serve as resource to obtain various other species studies and to compare milk composition values between closely related species.


The columns and values in the tables shown below are explained as follows:


1.) The first four columns are taxonomy identifiers as well as the common name for the species.


2.) "N" refers to the number of samples reported in the study (yellow shaded).


3.) "Solids (P+F+C+A)" indicates the sum of the reported values for protein, fat, carbohydrates and ash. This value is not taken from the study, but is simply a sum of the primary proximate analysis nutrient components. 


4.) "Solids (per study), total proteins, fat, carbs and ash" are all taken from the published studies (yellow shaded). Where a value was not reported, the cell is left blank. Where the total proteins where reported separately as casein and whey, those values are so indicated. 


5.) The "reference" column refers to the author and year of the study. The "source" column refers to  the publication where the study was originally published / or subsequently published in a larger compilation (see bottom of this web page for those references).



Cautions in using the data


As shown in column "N" that indicates the number of samples that were obtained and analyzed, many of the sample sizes are very small and likely not statistically significant for scientific comparability purposes. The number of samples is provided such that caution can be exercised to avoid over-reliance on values taken from a very small or unknown sample size.  


It is not known in most of the studies when during the female's lactation the samples were obtained. Since mammal milk changes during the lactation period, the reported values may be different in various stages of lactation. This could also explain some of the differences reported for certain milk values between studies for the same species.


The Solids (P+F+C+A) column is a calculated number, since some of the studies report a Total Solids value that does not equal the sum of the reported parts (proteins, fat, carbs and ash). This calculated number can be used in WildAgain's nutrition calculator to provide more meaningful results when constructing a recipe and comparing to mother's milk.

Deer milk values.jpg
Carnivore Milk Values.jpg
Bats and Lags Milk Values.jpg
Rodentia Milk Values.jpg



A.) Skibiel, Amy L., Downing, Lauren M., Orr, Teri J., and Hood, Wendy R. The evolution of the nutrient composition of mammalian milks. Journal of Animal Ecology 2013, 82, 1254-1264.


B.) Jenness, R. (1974). The composition of milk. In "Lactation: A Comprehensive Treatise" (B. L. Larson and V. R. Smith, eds.), pp. 3-107. Academic Press, NY.


C.) Nixon, Charles M., and W. J. Harper. Composition of gray squirrel milk. The Ohio Journal of Science 72(1):3, January 1972. Pp. 3-6.


D.) Evans, Richard H., DVM. Milk replacers and how to use them. In NWRA Principles of Wildlife Rehabilitation, 2nd edition. Adele Moore and Sally Joosten, eds. 2002. National Wildlife Rehabilitators Association, St Cloud, MN. Pp. 8.19-23.