Chronic Endrin Poisoning in Goldfish,Carassius auratus

Abstract

Endrin incorporated into the diet of mature male goldfish for 3–4 months affected growth, gonad development, thyroid activity, serum characteristics, total and differential body fat, behavior, and mortality. A biphasic response to endrin dosage was characteristic. The low doses (4.3–43 μg/kg body weight per day) either caused no detectable effect or were stimulatory, as seen from increased rates of growth and higher total body fat contents. The two highest doses (143 and 430 μg) caused mortality, lowered growth rates, and other chronic symptoms of endrin intoxication; they also caused decreased thyroid cell heights, decreased gametogenesis, and lowered total body fat, as well as less vacuolization in liver cells.All doses except the highest caused elevated serum Na concentrations. The fish receiving the highest dose suffered osmoregulatory failure. Induced spermiation was not affected; fish receiving 143 or 430 μg/kg had greatly reduced, but functional testes.