J. R. Reed

Oxidation Pond Algae as a Supplement for Commercial Catfish Feed

Investigations have shown that small (less than 10 cm) channel catfish fingerlings, Ictulurus punctatus Rafinesque, gained as much weight in a 10 week period on a diet of 25%-75% oxidation pond algae-commercial feed as did control animals fed 100% commercial feed. Larger fish (20-25 cm) fed the algal-supplemented diet did not gain as much weight in 10 weeks as did control fish on 100% commercial feed. Whole body protein and fat levels did not differ significantly between control and experimental fish.

A Study On The Biochemistry Of Alarm Substances In Fish

Two cyprinid fishes, rlinostomus funduloides and Notropis cornutus were tested with naturally occurring substances including some well-known biogenic amines. Behavioral responses to histamine were similar to those observed in previous tests with natural alarm substance extracts. A response threshold was obtained at 0.01 ppm. Spectrophotofluorometric emission spectra also indicated that the natural alarm substance known to exist in many species of fish may be a ringed or double ringed compound.