Pesticides induced changes in circulating thyroid hormones in the freshwater catfish Clarias batrachus.
1. Effects of endosulfan, malathion and carbaryl on circulating T4, T3 and T3/T4 ratio in the freshwater catfish, C. batrachus have been studied during reproductively active phases, i.e. vitellogenic and post-vitellogenic phases of its annual reproductive cycle. 2. Endosulfan provoked a significant increase in T4 and a decrease in T3 as well as the T3/T4 ratio. 3. Malathion decreased T3 and T3/T4 ratio without altering the level of T4 in circulation. 4. Carbaryl caused a decline in the level of T4 and an elevation in T3 and T3/T4 ratio.
Fish Endocrinology Laboratory, Banaras Hindu University, Varanasi, India.
N
N
Sinha
B
B
Lal
T P
TP
Singh
D000818:Animals; D002397:Catfishes / Q000097:blood*; D005260:Female; D007306:Insecticides / Q000633:toxicity*; D007928:Lethal Dose 50; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D007306:Insecticides; D014874:Water Pollutants, Chemical; D014284:Triiodothyronine; D013974:Thyroxine