Teratic larvae

Fig. 4. Toxicity of boric acid to catfish embryos and larvae. Exposure was maintained from fertilization through 4 days posthatching, using a continuous flow system. Teratic larvae were counted as lethals.

Egg samples from the four adult populations were also treated in vitro, using flow-through procedures and the dilution water described previously for embryo-larval tests. Mean mercury concentrations were 0.13 0.01 (fall strain), 0.26 0.04 (spring strain), 0.57 0.11 (fall strain), and 0.57 0.03 /ng/liter (spring strain), and survival of alevins at 4 days posthatching averaged 23, 9, 0, and 3%, respectively. Teratic larvae occurred at appreciable frequencies in hatched populations. Control survival averaged 89%. 

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