Abstract # 208:

Scheduled for Saturday, August 19, 2006 09:00 AM-09:30 AM: Session 19 (Regency East #2) Oral Presentation

A phylogenetic comparison of anthropoid primate milk composition

L. A. Milligan1,2, M. L. Power2,3 and O. T. Oftedal2
1Department of Anthropology, University of Arizona, Tucson, AZ 85721, USA, 2Nutrition Laboratory, Department of Conservation Biology, Smithsonian's National Zoological Park, Washington DC 20008 USA, 3Research Department, American College of Obstetricians and Gynecologists, Washington DC 20024 USA
     The lactation strategy of anthropoid primates is characterized by frequent nursing and the production of dilute milk that is low in energy relative to other mammalian orders. This generalization is based on analysis from a small number of anthropoid primate species, making it difficult to assess possible compositional patterns due to phylogeny, ecology, and life history. This study examined proximate composition of milks from 14 primate species, representing 11 genera from all anthropoid superfamilies (Pan, Gorilla, Pongo, Symphalangus, Hylobates, Macaca, Callithrix, Leontipithecus, Saimiri, Alouatta and Cebus) to investigate variation in milk composition among anthropoids. Sugar was the least variable component, ranging between 6.5 – 8% for New World monkeys, Old World monkeys and apes. Ape milk was more dilute and less variable (dry matter 9 – 12.5 %) compared to New World monkeys (11 - 23%) and Old World monkeys (13 - 23%) indicating that milk composition may be more tightly constrained among apes. This is reflected in fat values, which are highly variable in monkey species (1 - 16%) but consistently lower and less variable in apes (0.6 – 3.1%). Apes also have lower values for protein (0.5 – 1.6%) compared to monkeys (1.2 – 4.2%). These data suggest that variation in milk composition reflects phylogeny, however the phylogenetic pattern is confounded by differences in life history traits, maternal body size, and relative brain size between monkeys and apes.