The impact of dental impairment on ring‐tailed lemur food processing performance

Abstract

During mastication, foods are reduced into particles suitable for swallowing and digestion. Smaller particles possess a greater surface area per unit of volume on which digestive enzymes and bacteria may work than relatively larger particles, and are thus more readily digested. As dental morphology facilitates the breakdown of diets with specific mechanical properties, extensive dental wear and/or tooth loss may impede an individual's ability to break down and exploit foods. We present data demonstrating a relationship between dental impairment and particle size in 43 fecal samples from 33 ring-tailed lemurs at the Beza Mahafaly Special Reserve (BMSR), Madagascar. All fecal samples were sifted through three sieves of decreasing size (11.2 mm, 4.75 mm, and 1.0 mm). The resulting fraction in each sieve was then weighed and assessed in relation to individual dental impairment status. With increasing wear, the percentage of each sample within the 1.0 mm sieve decreases, whereas that in the 11.2 mm sieve increases with increasing postcanine wear, although these effects are not present when limited to individuals without tooth loss. Individuals with tooth loss also demonstrate larger proportions of fecal material 1.0-4.75 mm in size. Dental impairment results in larger food particles and potentially less efficient utilization of foods. When fecal material was examined by leaf vs. fruit content, individuals with tooth loss demonstrated reduced proportions of fruit in the 1.0 mm and 11.2 mm sieves. These data suggest individuals with tooth loss consume less fruit than those without loss, potentially reflecting a reduced ability to process tamarind fruit, a key fallback resource at BMSR.

Dust affects chewing efficiency and tooth wear in forest dwelling Western chimpanzees (Pan troglodytesverus)

“…In folivorous koalas it was found that increased tooth wear eventually impinges on the digestive efficiency (Lanyon & Sanson, ), although animals with worn teeth respond with an increased food intake and increased chewing intensity (Logan & Sanson, ). Studies on gallery forest ring‐tailed lemurs ( Lemur catta ) showed that dental abrasion reduced the efficiency with which food was processed and utilized; these lemurs were also observed to adjust their behavior to compensate for tooth loss (Milette et al, ). Furthermore, in rainforest lemurs ( Propithecus edwardsi ) increased tooth wear resulted in overall fitness decrease (King et al, ).…”

“…These authors hypothesized that the mainly frugivorous diet may be mechanically less challenging compared to the more folivorous diet of geladas. Likewise, Milette, Sauther, Cuozzo, and Ness () suggested for ring‐tailed lemurs ( Lemur catta ) that fruits are easier to process and digest than leaves, and Thiry et al () found that proboscis monkeys ( Nasalis larvatus ) had smaller FPS during the wet season when their feces contained higher amounts of seeds, indicating frugivory.…”

Age‐related changes in molar topography and shearing crest length in a wild population of mountain Gorillas from Volcanoes National Park, Rwanda

“…As folivorous primate teeth senesce, compensatory shearing crests become obliterated and teeth lose their ability to shear effectively through foods. This loss of shearing capacity is reflected in the inability to reduce food particles to the same degree as individuals with less worn teeth (King et al, 2005;Millette et al, 2012;Venkataraman et al, 2014). Furthermore, dentally senesced sifaka mothers experience decreases in infant survival, particularly during seasons of resource scarcity (King et al, 2005), indicating that extreme dental wear and the concomitant loss of compensatory shearing crests can have severe fitness consequences.…”

Physically Effective Fiber Threshold, Apparent Digestibility, and Novel Fecal Microbiome Identification of the Leopard Tortoise (Stigmochelys pardalis)

“…Diet particle size analysis could be problematic for studies utilizing free-ranging animals (Hummel et al, 2008;Millette et al, 2012;Matsuda et al, 2014), where sample collection of selected material would not be representative of the ingested material size of the study species. However, diet particle size may be an important feature for future studies to consider including, as it allows the researcher to determine particle size change along the gastrointestinal tract.…”