The presentation of orphan manatee calves to rehabilitation facilities poses numerous challenges from a husbandry standpoint as well as nutritionally. Calves may be found of varying ages, sizes, nutritional states, and illness. It is common to deal with emaciation, hypoglycemia, constipation, foreign body ingestion, diarrhea, bacteremia, colitis, ileus, and hypothermia among other findings. Calf mortalities were initially high until the application of neonatal care principles. While overall survival rates have improved there were still numerous complications encountered with dietary management. Success with one diet on one to two calves would often be followed by failure in the next one or two. Changes in availability of diet components, nutritional status and gastrointestinal compromise led to irreproducible results making it clinically apparent that we were "simply getting away with" different diets. Unfortunately, none were generally successful. The emphasis became focused on the composition of natural manatee milk which was initially reported by Bachman and Irvine. Since manatee calves present during all stages of nursing it was felt that the milk analysis should be repeated to incorporate expanded analytical techniques and to monitor changes throughout different periods of nursing.

Milk analysis was performed on samples from 5 individuals with one female sampled at 5 different times during nursing covering over one year. The samples were analyzed for amino acid composition, fatty acids, sugar content, total protein, total fat moisture and ash. It should be noted that these samples to date were obtained from captive animals so that analysis may be affected by dietary restrictions. It was also seen that the calf of the multi-sampled female only nursed on one side during the whole nursing period allowing analysis of a non-nursed mammary over the nursing period.

Protein analysis showed levels of 5.4 to 10% in all females examined and levels of 5.4 to 8.3% in the first female sampled through out nursing. Fat analysis showed a level of less than 1 gm of lipid in colostrum to 18 gms per 100 mls during the nursing period. Manatee milk is high in 12:0, 16:0, 18:1 fatty acids. Sugar analysis is currently underway. The short-term implications of the information have led to the addition of canola oil to the current diet of Esbilac. This addition has also led to increased weight gain and a decrease in problems with constipation commonly seen with esbilac use in this species. The long-term implications will be the development of a diet formulated to more closely approximate natural manatee milk.