Oxygen Consumption during Spontaneous Amphibian Metamorphosis

Energetics of metamorphic climax in the southern toad ( Bufo terrestris )

“…Because of the energetic requirements of metamorphic climax, the minimum age at which an individual can metamorphose may be limited by the need to store energy (Crump 1981). Although metabolic rate during metamorphic climax has been measured in several species of anurans (Funkhouser and Mills 1969;Funkhouser and Foster 1970;Sivula et al 1972;Feder 1982), total energy expenditures during metamorphic climax have only been examined in one other species (Rana tigrina; Pandian and Marian 1985). Furthermore, the extent to which energy metabolism during metamorphosis varies among and within species of anurans, and what factors might lead to variation in energy metabolism, remain largely unexplored.…”

“…Resting metabolic rates of amphibian larvae are quite variable among species (see Table 12.3 in Gatten et al 1992). In addition, metabolic rates may vary throughout development within a species (e.g., Funkhouser and Mills 1969;Funkhouser and Foster 1970;Sivula et al 1972). Although much variation in metabolic rate during development is due to changes in body mass (Feder 1982), the relationship between body mass and metabolic rate may not be constant throughout development (Feder 1982).…”

Dynamics of body mass and oxygen consumption in the ontogeny of the Spanish ribbed newt (Pleurodeles waltl): 2. Larval stage

“…The oxygen consumption intensity decreases dur ing newt larval development, as in the case of most studied amphibian species (Etkin, 1934;Fletcher, Myant, 1959;Funkhouser, Mills, 1969;Feder, 1982;Vladimirova et al, 2003). During the metamorphosis period, only an insignificant decrease in the oxygen consumption intensity can be pointed out.…”

“…As a result, the newts that have undergone metamorphosis have a greater body mass than the larvae entering it. This trait sets the Spanish ribbed newt apart from the studied represen tatives of anurans, in which the metamorphosis pro cess is accompanied by body mass decrease caused by cessation of feeding due to the reorganization of mouth parts and the gastrointestinal tract (Wills, 1936;Fletcher, Myant, 1959;Funkhouser, Mills, 1969;Schwartz et al, 1973;Beck, Congdon, 2003;Orlofske, Hopkins, 2009). The morphological and functional changes in organs, including the digestive system, that take place during metamorphosis, in the case of the Spanish ribbed newt, a representative of tailed amphibians, are less profound than in anurans, which, obviously, explains why their larva body mass does not decrease during metamorphosis (Fig.…”

“…After the larva switches to external nutrition, the ratio between these coefficients changes; the value of the power coefficient k lies in the range between 0.78 and 1 in most studied amphibian species and does not change until metamorphosis (Funkhouser, Mills, 1969;Feder, 1982;Vladimirova et al, 2003). During the metamorphosis process, the parameters of the dependence between oxygen consumption and body mass change in some amphibian species (Feder, 1982;Beck, Congdon, 2003) and remain the same as earlier in others (Funkhouser, Mills, 1969).…”