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Showing papers by "Michael L. Power published in 2010"


Book ChapterDOI
01 Jan 2010
TL;DR: Interestingly, however, these marmosets share an ability to digest gum despite their differences in gum kinetics, and in captivity both species have been shown to be more able to digest Acacia gum than related species that feed less often on gum in the wild.
Abstract: Gum is an unusual food that presents significant challenges to animals that feed on it. Gum is limited in availability; trees generally secrete it only in response to damage. Gum is a β-linked complex polysaccharide, and as such is resistant to mammalian digestive enzymes and requires fermentation by gut microbes. It contains little or no lipid, low amounts of protein, and no appreciable levels of vitamins. As a food, gum can be characterized as difficult to obtain, potentially limited in quantity, difficult to digest, and primarily a source of energy and minerals. Despite these drawbacks, many primates feed extensively on gums. Among mammals, gum-feeding largely appears to be a primate dietary adaptation. Why are there so many primate gum-feeders and what adaptations have allowed them to make a living on such a problematic food? This is the central question of this book. This chapter examines digestive and nutritional aspects of gum. Specific examples of biological adaptations found in common and pygmy marmosets (Callithrix jacchus and Cebuella pygmaea), small New World primate gum-feeding specialists, will be examined. These marmoset species have many similarities in their behavior, morphology and metabolism, but also some instructive differences in their digestive function. C. pygmaea is the smallest of the marmosets but has the slowest passage rate of digesta. This might represent an adaptation to retain difficult-to-digest material, such as gum, within the gut to allow fermentation. In contrast, C. jacchus has a rapid passage rate. Passage rate in C. jacchus appears adapted more for rapidly excreting indigestible material (e.g., seeds) than for retaining gum within the gut to enable more complete digestion. Fruit is a rare component of C. pygmaea’s diet; hence any constraint on feeding caused by filling the gut with ingested seeds is greatly relaxed, apparently enabling digestive kinetics that favor digestive efficiency over maximizing food intake. Interestingly, however, these marmosets share an ability to digest gum despite their differences in gum kinetics. In captivity both species have been shown to be more able to digest Acacia gum than related species that feed less often on gum in the wild.

67 citations


Journal ArticleDOI
TL;DR: Further research is needed to determine the extent to which the milk oligosaccharide patterns observed among these taxa represent wider phylogenetic trends among primates and how much variation occurs among individuals or species.
Abstract: Human and great ape milks contain a diverse array of milk oligosaccharides, but little is known about the milk oligosaccharides of other primates, and how they differ among taxa. Neutral and acidic oligosaccharides were isolated from the milk of three species of Old World or catarrhine monkeys (Cercopithecidae: rhesus macaque (Macaca mulatta), toque macaque (Macaca sinica) and Hamadryas baboon (Papio hamadryas)) and three of New World or platyrrhine monkeys (Cebidae: tufted capuchin (Cebus apella) and Bolivian squirrel monkey (Saimiri boliviensis); Atelidae: mantled howler (Alouatta palliata)). The milks of these species contained 6–8% total sugar, most of which was lactose: the estimated ratio of oligosaccharides to lactose in Old World monkeys (1:4 to 1:6) was greater than in New World monkeys (1:12 to 1:23). The chemical structures of the oligosaccharides were determined mainly by 1H-NMR spectroscopy. Oligosaccharides containing the type II unit (Gal(β1-4)GlcNAc) were found in the milk of the rhesus macaque, toque macaque, Hamadryas baboon and tufted capuchin, but oligosaccharides containing the type I unit (Gal(β1-3)GlcNAc), which have been found in human and many great ape milks, were absent from the milk of all species studied. Oligosaccharides containing Lewis x (Gal(β1-4)[Fuc(α1-3)]GlcNAc) and 3-fucosyl lactose (3-FL, Gal(β1-4)[Fuc(α1-3)]Glc) were found in the milk of the three cercopithecid monkey species, while 2-fucosyl lactose (5'-FL, Fuc(α1-2)Gal(β1-4)Glc) was absent from all species studied. All of these milks contained acidic oligosaccharides that had N-acetylneuraminic acid as part of their structures, but did not contain oligosaccharides that had N-glycolylneuraminic acid, in contrast to the milk or colostrum of great apes which contain both types of acidic oligosaccharides. Two GalNAc-containing oligosaccharides, lactose 3′-O-sulfate and lacto-N-novopentaose I (Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc) were found only in the milk of rhesus macaque, hamadryas baboon and tufted capuchin, respectively. Further research is needed to determine the extent to which the milk oligosaccharide patterns observed among these taxa represent wider phylogenetic trends among primates and how much variation occurs among individuals or species.

39 citations


Journal ArticleDOI
TL;DR: Despite decreased optimism about the likelihood of patients following advice, modest improvements occurred in some obstetrician/gynecologists' obesity prevention practices between 2005 and 2007.
Abstract: Objective: To describe associations between dissemination of educational materials and U.S. obstetrician/gynecologists' prevention and management of obesity in nonpregnant patients. Method...

17 citations


Journal ArticleDOI
26 Mar 2010-Primates
TL;DR: A reduction in litter size allows C. goeldii mothers to spend more time carrying their infant and to delay weaning, thereby allowing accelerated infant and juvenile growth rates compared with C. jacchus.
Abstract: Callimico goeldii gives birth to single offspring, whereas other callitrichids, including Callithrix jacchus, twin. This study compares maternal effort and infant development in C. goeldii and C. jacchus; it is the first study to look at nursing frequency. Infants were observed from birth for 7 weeks in two captive groups each of C. goeldii and C. jacchus. C. goeldii mothers physiologically invested the same or less than C. jacchus mothers. C. goeldii mothers gained the same amount of weight during pregnancy in absolute terms as did the smaller C. jacchus. This results in a smaller gain in proportion to maternal weight but an equivalent proportional gain on a per fetus basis. C. goeldii mothers nursed their infants less based on duration of nursing bouts compared with C. jacchus mothers. C. goeldii mothers transported their infants exclusively through the first 2 weeks of life, which is longer than C. jacchus mothers, who exclusively transported infants only during the first week of life. As maternal infant carriage declined, other group members transported offspring in both species. C. goeldii infants engaged in independent locomotive sequences later in development and tasted solid foods less frequently than C. jacchus infants when compared at equivalent ages. A single, opportunistic milk sample obtained from a C. goeldii mother when her infant was 48 days old indicates that C. goeldii milk contains gross energy from crude protein within the range of variation observed in Callithrix milk. Despite the similarities in milk quality and prenatal effort in individual fetuses, C. goeldii infants gain weight faster from 0 to 18 months than do C. jacchus infants. A reduction in litter size allows C. goeldii mothers to spend more time carrying their infant and to delay weaning, thereby allowing accelerated infant and juvenile growth rates compared with C. jacchus.

9 citations


01 Jan 2010
TL;DR: The anthropoid primate placenta appears to be unique in producing corticotropin-releasing hormone (CRH), and there are at least two patterns of maternal circulating CRH across gestation among anthropoids as mentioned in this paper.
Abstract: The anthropoid primate placenta appears to be unique in producing corticotropin‐releasing hormone (CRH). Placental CRH is involved in an endocrine circuit key to the production of estrogens during pregnancy. CRH induces cortisol production by the maternal and fetal adrenal glands, leading to further placental CRH production. CRH also stimulates the fetal adrenal glands to produce dehydroepiandrostendione sulfate (DHEAS), which the placenta converts into estrogens. There are at least two patterns of maternal circulating CRH across gestation among anthropoids. Monkeys examined to date (Papio and Callithrix) have an early‐to‐mid gestational peak of circulating CRH, followed by a steady decline to a plateau level, with a possible rise near parturition. In contrast, humans and great apes have an exponential rise in circulating CRH peaking at parturition. To further document and compare patterns of maternal circulating CRH in anthropoid primates, we collected monthly blood samples from 14 squirrel monkeys (Saimiri boliviensis) and ten owl monkeys (Aotus nancymaae) during pregnancy. CRH immunoreactivity was measured from extracted plasma by using solid‐phase radioimmunoassay. Both squirrel and owl monkeys displayed a mid‐gestational peak in circulating CRH: days 45–65 of the 152‐day gestation for squirrel monkeys (mean±SEM CRH=2,694±276 pg/ml) and days 60–80 of the 133‐day gestation for owl monkeys (9,871±974 pg/ml). In squirrel monkeys, circulating CRH declined to 36% of mean peak value by 2 weeks before parturition and then appeared to increase; the best model for circulating CRH over gestation in squirrel monkeys was a cubic function, similar to previous results for baboons and marmosets. In owl monkeys, circulating CRH appeared to reach plateau with no subsequent significant decline approaching parturition, although a cubic function was the best fit. This study provides additional evidence for a mid‐gestational peak of maternal circulating CRH in ancestral anthropoids that has been lost in the hominoid lineage. Am. J. Primatol. 72:1004–1012, 2010. © 2010 Wiley‐Liss, Inc.

7 citations


Journal ArticleDOI
TL;DR: Evidence is provided for a mid‐gestational peak of maternal circulating CRH in ancestral anthropoids that has been lost in the hominoid lineage.
Abstract: The anthropoid primate placenta appears to be unique in producing corticotropin-releasing hormone (CRH). Placental CRH is involved in an endocrine circuit key to the production of estrogens during pregnancy. CRH induces cortisol production by the maternal and fetal adrenal glands, leading to further placental CRH production. CRH also stimulates the fetal adrenal glands to produce dehydroepiandrostendione sulfate (DHEAS), which the placenta converts into estrogens. There are at least two patterns of maternal circulating CRH across gestation among anthropoids. Monkeys examined to date (Papio and Callithrix) have an early-to-mid gestational peak of circulating CRH, followed by a steady decline to a plateau level, with a possible rise near parturition. In contrast, humans and great apes have an exponential rise in circulating CRH peaking at parturition. To further document and compare patterns of maternal circulating CRH in anthropoid primates, we collected monthly blood samples from 14 squirrel monkeys (Saimiri boliviensis) and ten owl monkeys (Aotus nancymaae) during pregnancy. CRH immunoreactivity was measured from extracted plasma by using solid-phase radioimmunoassay. Both squirrel and owl monkeys displayed a mid-gestational peak in circulating CRH: days 45–65 of the 152-day gestation for squirrel monkeys (mean±SEM CRH=2,694±276 pg/ml) and days 60–80 of the 133-day gestation for owl monkeys (9,871±974 pg/ml). In squirrel monkeys, circulating CRH declined to 36% of mean peak value by 2 weeks before parturition and then appeared to increase; the best model for circulating CRH over gestation in squirrel monkeys was a cubic function, similar to previous results for baboons and marmosets. In owl monkeys, circulating CRH appeared to reach plateau with no subsequent significant decline approaching parturition, although a cubic function was the best fit. This study provides additional evidence for a mid-gestational peak of maternal circulating CRH in ancestral anthropoids that has been lost in the hominoid lineage. Am. J. Primatol. 72:1004–1012, 2010. © 2010 Wiley-Liss, Inc.

7 citations