A comparison of energy substrates and reproductive patterns of two anurans, Acris crepitans and Bufo woodhousei

Long, David R.

doi:10.1016/0300-9629(87)90429-4

Cited by 21 publications

(29 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These were: (1) an increase in V CO2 during cooling, but before the initiation of ice formation (which we henceforth call the 'cooling threshold'); (2) an increase in V CO2 upon freezing; and (3) an increase in V CO2 during thawing (Fig.1). We assumed that lipid was the main fuel source when the frogs were unfrozen [as is the case for all dormant frogs that have been studied (Fitzpatrick, 1976;Long, 1987;Tattersall and Ultsch, 2008)], but that metabolism during freezing, thawing and while frozen was fuelled by carbohydrate (Storey and Storey, 1986). We then used this simulation to predict CO 2 production from microclimate data (see Marshall and Sinclair, 2012) from the microhabitat temperature recordings, and calculated expected total overwinter carbohydrate and lipid consumption (Fig.2).…”

Section: Discussionmentioning

confidence: 99%

“…However, we did explore the consequences of this assumption in our sensitivity analyses. Previous studies have indicated that while frozen, R. sylvatica is dependent on carbohydrate metabolism (Storey and Storey, 1986), and we assumed that, when unfrozen, lipid stores provide the main fuel source (Fitzpatrick, 1976;Long, 1987;Tattersall and Ultsch, 2008). We assumed that carbohydrates were the fuel source during bursts of CO 2 production in cooling, freezing and thawing, and that carbohydrates provided all metabolic fuel when the frogs were frozen.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Real-time measurement of metabolic rate during freezing and thawing of the wood frog,Rana sylvatica: implications for overwinter energy use

Sinclair

Stinziano

Williams

et al. 2013

Journal of Experimental Biology

109

View full text Add to dashboard Cite

SUMMARYEctotherms overwintering in temperate ecosystems must survive low temperatures while conserving energy to fuel post-winter reproduction. Freeze-tolerant wood frogs, Rana sylvatica, have an active response to the initiation of ice formation that includes mobilising glucose from glycogen and circulating it around the body to act as a cryoprotectant. We used flow-through respirometry to measure CO 2 production (V CO2 ) in real time during cooling, freezing and thawing. CO 2 production increases sharply at three points during freeze-thaw: at +1°C during cooling prior to ice formation (total of ). We interpret these increases in metabolic rate to represent the energetic costs of preparation for freezing, the response to freezing and the re-establishment of homeostasis and repair of damage after thawing, respectively. We assumed that frogs metabolise lipid when unfrozen and that carbohydrate fuels metabolism during cooling, freezing and thawing, and when frozen. We then used microclimate temperature data to predict overwinter energetics of wood frogs. Based on the freezing and melting points we measured, frogs in the field were predicted to experience as many as 23 freeze-thaw cycles in the winter of our microclimate recordings. Overwinter carbohydrate consumption appears to be driven by the frequency of freeze-thaw events, and changes in overwinter climate that affect the frequency of freeze-thaw will influence carbohydrate consumption, but changes that affect mean temperatures and the frequency of winter warm spells will modify lipid consumption. Supplementary material available online at

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Real-time measurement of metabolic rate during freezing and thawing of the wood frog,Rana sylvatica: implications for overwinter energy use

Sinclair

Stinziano

Williams

et al. 2013

Journal of Experimental Biology

109

View full text Add to dashboard Cite

show abstract

“…In some species of temperate anurans, testes exhibit seasonal fluctuations in size (Lofts 1974;Rastogi et al 1986;Long 1987). Breeding males of Japanese anuran species were thus collected during the peak breeding seasons of 1986-1990 to adjust for the reproductive state, except for early breeding species such as Rana sakuraii, (Iwasawa 1987), males were collected late in that season.…”

Section: Methodsmentioning

confidence: 99%

Testes size and breeding systems in Japanese annrans with special reference to large testes in the treefrog, Rhacophorus arboreus (Amphibia : Rhacophoridae)

Kusano

Toda

Fukuyama

1991

Behav Ecol Sociobiol

View full text Add to dashboard Cite

Testes size was compared among 19 species of Japanese anurans in relation to their breeding systems. Although the mean body mass of the species examined varied markedly between 1.8 and 116 g, the mean proportion of testes mass to body mass was fairly constant at 0.2 to 0.4% across all species except the rhacophorid species. Foam-nest building rhacophorids had relatively large testes constituting more than 1% of their body mass. Among them, Rhacophorus arboreus had the largest, exceeding 5% of the body mass. Multi-male breeding, where a female is grasped by two or more males during spawning, occurs frequently in these rhacophorids, especially in R. arboreus. This close association between large testes size and multi-male breeding strongly suggests that sperm competition is an important factor affecting the evolution of relative testes size in Japanese anurans.

show abstract

“…Our data showed that R. epeirotica retain enlarged follicles for ovulation in subsequent years. This also was reported for certain semi-arid anurans (Long, 1987). We could adopt the aspect of Long (1987) that this happens because of climatic vagaries that might reduce foraging opportunities, resulting in insuf cient ingestion of nutrients.…”

Section: Discussionmentioning

confidence: 56%

Female reproductive cycle of the water frog Rana epeirotica in northwestern Greece

Tsiora¹,

Kyriakopoulou-Sklavounou²

2002

Amphib Reptilia

View full text Add to dashboard Cite

The reproductive cycle of female Rana epeirotica in Lake Ioannina, northwestern Greece was studied from 1998 to 1999. Young females reached sexual maturity at a weight of 26.3 g and a length of 67.2 mm. The annual cyclic changes in weight and histological composition of the ovaries showed that R. epeirotica has a single reproductive period each year. Weight changes of the oviducts followed those shown by the ovaries. A continuous change in the percentage and diameter size of the ovarian follicles through the annual cycle was found. Clutch size ranged from 600 to 2900 ova of 1.3 to 1.6 mm egg diameter. Ovarian weight, clutch size and ovum size were positively correlated to body weight. The weights of fat body and liver had a peak in August and November respectively and they both were reduced considerably during hibernation.

show abstract

A comparison of energy substrates and reproductive patterns of two anurans, Acris crepitans and Bufo woodhousei

Cited by 21 publications

References 27 publications

Real-time measurement of metabolic rate during freezing and thawing of the wood frog,Rana sylvatica: implications for overwinter energy use

Real-time measurement of metabolic rate during freezing and thawing of the wood frog,Rana sylvatica: implications for overwinter energy use

Testes size and breeding systems in Japanese annrans with special reference to large testes in the treefrog, Rhacophorus arboreus (Amphibia : Rhacophoridae)

Female reproductive cycle of the water frog Rana epeirotica in northwestern Greece

Contact Info

Product

Resources

About