EFFECTS OF GENOTYPE, DIETARY PROTEIN AND ENERGY ON THE REPRODUCTIVE AND GROWTH TRAITS OF PARENTS AND F1 HATCHLINGS OF Achatina achatina (L) SNAILS IN NIGERIA
Okon, B., Ibom, L. A., Ettah, H. E.; Ukpuho, I. E.

Abstract
Ninety (90) adult breeder snails, forty-five (45) each of the black-skinned (BS) and white-skinned (WS) ectotypes were fed on a mixed feeding regime of pawpaw leaves (Carica papaya) supplemented with formulated diets containing different protein and energy levels to evaluate the reproductive and growth performance traits of these snails and their F1 offspring respectively. The weights of the parent snails ranged from 58.25 g to 60.75 g. Three (3) mating groups or genotypes namely BS x BS, WS x WS and BS x WS consisted the five (5) treatment groups, corresponding to the different protein and energy level diets. Each group was replicated three (3) times with two (2) snails to a replicate in the randomized complete block design (RCBD). Traits measured on the parent breeder snails included clutch size, incubation period (days), percent hatchability and weight of hatchling at day-old (g), while final body weight (g) and feed intake (g) were measured on the F1 hatchlings. Body weight gain (g), daily growth rate (g/day) and feed efficiency of the F1 hatchlings were estimated from the two traits earlier measured. Results of the study showed that significantly differences (P<0.05) existed in reproductive traits (clutch size, egg weight and percent hatchability) and growth performance traits (final weights, increment in shell length, shell width, aperture length and aperture width). The purebred BS genotype is the best genotype in terms of clutch size among the three genotypes studied. Prospective snail farmers are encouraged to select BS genotype of A. achatina for rearing under good environment with 23 % protein and 2995 Kcal/kgME for faster reproductive and growth traits, and better return on investment.

Full text: PDF