The suitability of snail (Pomacea sp.) meal as substitute for fish meal in diets of cage-cultured Nile tilapia (Oreochromis niloticus) at three stocking density levels

• Main Author: Reazo, Dante M.
• Format: text
• Language: English
• Published: Animo Repository 1988
• Subjects: Nile tilapia > Feeding and feeds; Snails
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/1206
• Institution: De La Salle University

The suitability and efficacy of formulated feed containing snail meal (SM) was formally evaluated in relation to a fish meal-based diet (FM) and without feeding (Fc) by the growth performance of cage-cultured Oreochromis niloticus. This nutritional bioassay was carried out at three stocking densities of 5, 15 and 30 fish/m3 (D1, D2 and D3). Each treatment combination was replicated in a 123.38m2 concrete pond each over 90 days. Fish in cages that received feed were fed twice daily (one half of the ration at 7:00 a.m. and half at 5:00 p.m.) at a rate of 10 percent of body weight for the first 45 days and 5 percent of body weight for the remainder of the culture period. The average growth (final weight, weight gain and daily weight gain) of O. niloticus at all densities grown on snail meal-based diet (SM) was superior to that obtained with fish meal-based diet (FM) and without feeding (Fc) with extreme statistical differences at 5 percent level of significance. On the other hand, the average growth (final weight, weight gain and daily weight gain) of fed (FM & SM) and unfed (Fc) fish between stocking densities was found highest at 5/m3 (D1), followed by 15/m3 (D2) and 30/m3 (D3) respectively, with statistically significant variations (P0.05). The feed conversion ratio (FCR) was highest (2.5) at 5 fish/m3 (D1) fed with diet SM, followed by those fed with diet FM (2.7). However, the fish fed both diets at stocking densities of 15 and 30/m3 (D2 and D3) gave similar FCR of 2.9 and 3.1, respectively. In addition, 100 percent survival was noted at all treatment combinations except for those stocked at 30 fish/m3 (D3) without feeding (Fc). Finally, the data obtained on physico-chemical parameters (pH, Temperature, Dissolved Oxygen, Phosphate and Nitrate) of interest in this experiment for the entire days of culture (90 days) were within the range of tolerance of the experimental fish, O. Niloticus.