Effects of Meal Size, Meal Type, Body Temperature, and Body Size on the Specific Dynamic Action of the Marine Toad, Bufo marinus

Specific dynamic action (SDA), the cumulative energy expended on digestion and assimilation, can contribute significantly to individual daily energy expenditure (DEE). The Common Garter Snake (Thamnophis sirtalis (L., 1758)) is a widely distributed generalist predator that could experience considerable variation in SDA and hence the contribution of SDA to DEE. We examined the effects of meal size, meal type, and body temperature on the postprandial metabolic response and SDA of the Eastern Garter Snake ( Thamnophis sirtalis sirtalis (L., 1758)) and generated predictive models of SDA based on meal size, body mass, and body temperature, and separately based on meal energy. Postprandial peak in oxygen consumption, duration of significantly elevated oxygen consumption, and SDA increased with increasing meal size (5%–45% of body mass). Postprandial metabolic response digesting six different equal-size prey items varied significantly; vertebrate prey generated larger SDA responses than soft-bodied invertebrates. Increases in experimental temperature (15–35 °C) yielded a matched increase in postprandial peak in oxygen consumption and decrease in digestive duration. For a 1-month hypothetical feeding history for an adult T. sirtalis, the cumulative predicted SDA varied by 4.5% among the three models (minimal, intermediate, and maximal intake of prey) and averaged 8%, 22%, and 38% of DEE, respectively.

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Ratio Representations of Specific Dynamic Action (Mass‐Specific SDA and SDA Coefficient) Do Not Standardize for Body Mass and Meal Size

Physiological and Biochemical Zoology ◽

10.1086/425195 ◽

2005 ◽

Vol 78 (1) ◽

pp. 126-131 ◽

Cited By ~ 24

Author(s):

Steven J. Beaupre

Keyword(s):

Body Mass ◽

Specific Dynamic Action ◽

Meal Size ◽

Dynamic Action

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Specific dynamic action, apparent assimilation efficiency, and digestive rate in an arboreal pitviper, Trimeresurus stejnegeri stejnegeri

Canadian Journal of Zoology ◽

10.1139/z08-090 ◽

2008 ◽

Vol 86 (10) ◽

pp. 1139-1151 ◽

Cited By ~ 16

Author(s):

Tein-Shun Tsai ◽

How-Jing Lee ◽

Ming-Chung Tu

Keyword(s):

Assimilation Efficiency ◽

Specific Dynamic Action ◽

Meal Size ◽

Digestive Physiology ◽

Postprandial Metabolism ◽

Preferred Temperature ◽

Time To Peak ◽

Dynamic Action ◽

Effects Of Temperature ◽

Arboreal Snakes

The major aims of this study were to assess the effects of temperature (15–35 °C) and meal size (less than 30% snake mass) on the metabolism and digestive physiology of Trimeresurus stejnegeri stejnegeri Schmidt, 1925 and to compare the results with those of terrestrial snakes. Specific dynamic action (SDA), peak Vo2, and scope of peak Vo2 increased with meal size. Temperature had little effect on SDA. With regression analysis, we found that baseline metabolic rates of T. s. stejnegeri were generally smaller than that for frequent feeders and larger than that for infrequent feeders. We generalized three types of SDA profiles among T. s. stejnegeri and terrestrial snakes (including frequent and infrequent feeders). Trimeresurus stejnegeri stejnegeri had a more shallow and extended profile of postprandial metabolism, which did not support our hypothesis that the pace of digestive metabolism of arboreal snakes is faster than that of terrestrial snakes. The apparent assimilation efficiency (range 0.698–0.884) was significantly lower at 15 °C. At the preferred temperature (26.5–28.8 °C) for a postprandial 50 g snake, the simulated ratios of four parameters (time to peak Vo2, first defecation time, gastric digestion time, and final defecation time) to SDA duration approximated 0.2, 0.5–0.7, 0.7, and 1.1, respectively.

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