Abstract:
The study was carried out to investigate the growth performance of juvenile African giant land snails fed diets containing wild castor oil seed meal. The experimental animals were randomly assigned to four treatments with different inclusion levels of castor oil seed meal which replaced groundnut cake at 0%(diet I, control), 25%(diet II), 50%(diet III) and 75%(diet IV) respectively. The performance of the snails on each diet was observed for a period of 56 days. It was observed that the snails fed on diet II had the highest average weight gain (39.6g) followed by diet I and diet IV. The least was recorded for diet III (25.9g).Significant differences (p<0.05) existed among body weight of Archachatina marginata fed on diet II and the snails fed on other diets. African giant land snails fed on diet I, II and III had similar influence (p>0.05) on their body weight gains. An average increase in shell width was recorded for diet III (4.54cm) followed by diets II, IV and I respectively (4.45g, 4.40g and4.26g). The highest average shell length increase was recorded for diet IV (7.41cm) followed by diet II (7.32cm), diet III and diet I respectively. Analysis of Variance also shows that there were significant differences(p<0.05) in shell length of A.marginata fed diets I,II and III, but there was no significant difference(p>0.05) in the increase in shell width of animals under all the diets observed during the study, except for diet IV having the highest mean value.
The result of the organoleptic assessment of Archachatina margisnata fed different inclusion levels of wild castor oil seed meal showed that there were no significant differences (p>0.05) among all the parameters measured during the organoleptic assessment, except for ‘taste’ under diet III which had a higher mean value. Protein digestibility was very in all treatments. The protein in diet I to IV was 28.37%, 30.93%, 29.40% and 27.64%. The result of the proximate composition of feacal samples showed that in diet I, 17.77% of protein was digested from the protein content of the feed. 18.19% was digested in diet II, 15.25% in diet III and 14.32% in diet IV.
This study therefore concludes that wild castor oil seed meal could be used as a replacement for groundnut cake up to 75% level in the diet of African giant land snails and it does not affect the protein digestibility by the snails and the nutritive value and general acceptability of the snail meat to man.
