Two trials were conducted at the BOCM Silcock Development Unit at Stoke Mandeville. The first trial evaluated the response on doe and progeny, from mating to 8 weeks after parturition, of rabbit compound diets containing 0, 100, 200 and 300 g sodium hydroxide-treated straw per kg. Performance data showed no detrimental effect of inclusion levels up to 300 g sodium hydroxide-treated straw per kg despite its high sodium concentration.

A second trial was made to ascertain whether these findings were due to the treated straw itself or to increasing sodium concentrations. A standard rabbit compound diet containing 2·5 g sodium per kg was compared with diets containing either 5·0 or 10·0 g sodium per kg, and with experimental compound diets containing either 80 g sodium hydroxide-treated straw or 80 g untreated straw per kg and both containing 2·5 g sodium per kg. Peak food conversion was estimated to occur at a dietary sodium concentration of 4·6g/kg, although the slope of the dose response curve was not statistically significant at the P ≤ level.

The results indicate that compound diets containing up to 80 to lOOg sodium hydroxide-treated straw per kg may be fed to rabbits and that inclusion of levels of up to 300 g sodium hydroxide-treated straw per kg are not detrimental to performance. On the other hand, an inclusion of 80 g untreated ground straw per kg in compound diets for rabbits had a growth-depressing effect.