Unidentified growth factors in fish meal: Experiments with organic arsenic compounds in broiler diets

Synopsis

The effect of adding 50 ppm arsenilic acid and 0.36 and 1.8% of an Ascontaining cod liver hydrolysate (140 ppm As of DM) to a plant protein diet and a similar diet containing 5% capelin meal, was tested in a 2 × 4 factorial experiment. The experiment involved 960 broiler chicks from hatching to 7‐weeks‐old.

Compared with the plant protein diet the addition of 5% capelin meal gave a 4% increase in growth rate and 3% better utilisation of food. These effects were, however, not statistically significant. There was no significant interaction between the fish meal and the other additives.

In agreement with earlier investigations, the retention of arsenic from arsenilic acid was small whereas a large portion of the arsenic compound present in cod liver was retained by the chicks. Arsenic in the capelin meal was less readily retained.