Bufo melanostictus

About: Bufo melanostictus is a research topic. Over the lifetime, 196 publications have been published within this topic receiving 1168 citations.

Changes in Plasma Sex Steroids in Relation to Reproductive Behavior of the Toad, Bufo melanostictus (Schn.)

Abstract: Steroid hormones play a critical role in the regulation of reproductive behavior of many amphibians. Changes in the plasma concentration of steroid hormones (testosterone, estradiol, and progesterone) in relation to sexual behavior of males and females were studied in a natural population of the toad (Bufo melanostictus) during the breeding season. Changes in plasma sex steroids were positively correlated with the sexual behavior of male and female toads. Plasma testosterone was low in calling males but reached a peak during amplexus before declining in the spawning and post-spawning males. Plasma estradiol and progesterone increased with the onset of sexual behavior in solitary females ready to breed, reaching a peak during spawning before declining in post-spawning females. The study reveals that B. melanostictus belongs to the type of ‘associated reproductive pattern’ in which plasma steroid hormone concentration is highly correlated with the sexual behavior of male and female toads.

Effects of diazinon on survival and growth of two amphibian larvae

Abstract: Amphibian populations are declining globally at an alarming rate and evidence suggests that pesticides may be a principal cause. The present study investigated the effects of diazinon on the survival and growth of larvae of two amphibians, Bufo melanostictus (Asian common toad) and the Sri Lankan endemic Polypedates cruciger (Common hourglass frog). Larvae were laboratory bred from egg clutches collected from ponds and wells in home gardens in the Gampaha and Colombo districts. Two separate trials were conducted using gill stage hatchlings (Gosner stages 20-22) of each species. The larvae were repeatedly exposed to 4 μg/L, 400 μg/L and 10 mg/L of diazinon for seven days. Results showed that exposure to 10 mg/L of diazinon caused significant elevations (p B. melanostictus and P. cruciger as compared to the controls. No significant increases in mortality were noted at 4 μg/L and 400 μg/L. The trends in mortality were significant and positive for both species. Growth retardation was also noted at the highest dose of 10 mg/L, these larvae being significantly smaller than those in the controls (p Keywords: Amphibian, Bufo melanostictus , diazinon, mortality, organophosphate pesticide, Polypedates cruciger , tadpoles doi:10.4038/jnsfsr.v36i2.149 Journal of the National Science Foundation of Sri Lanka 36 (2) 165-169