Hormonal Concentration of Controlled and Naturally Induced Aestivated Snails (Archachatina marginata) at Different Reproductive Phases
O. E. Okhale
Department of Animal Science, Faculty of Agriculture, University of Benin, Benin City, Nigeria
J. M. Omoyakhi *
Department of Animal Science, Faculty of Agriculture, University of Benin, Benin City, Nigeria
O. Edo-Taiwo
Department of Animal and Environmental Biology, Faculty of Life Science, University of Benin, Benin City, Nigeria
O. T. Aremu
Department of Forestry and Wildlife, Faculty of Agriculture, University of Benin, Benin City, Nigeria
*Author to whom correspondence should be addressed.
Abstract
Aims: This research was carried out to examine changes in some hormones perceived to be implicated in the reproduction of giant African land snail (GALS) subjected to varied aestivation lengths and nature have driven natural cycle.
Study Design: Randomized complete block design (RCBD).
Place and Duration of Study: University of Benin Teaching and Research Farm, between November 2015 and October 2016.
Methodology: Apparently healthy Archachatina marginata species of snails were grouped into five. Group 0A was fed and watered throughout the experimental period. Group 6A and 12A were subjected to periods 6 - and 12 - week unbroken aestivation period while snails in group NA and WA were controlled by natural weather elements in captivity and the wild respectively. Hormonal concentrations were determined from each group in a year circle and grouped into reproductive phases.
Results: At dormancy phase, no significant differences were observed among treatments in all studied hormones except the progesterone and testosterone. The estradiol concentration in the pre-spawning phase was significantly higher (57.40 pg/mL) as compared with other treatment groups. During the post-spawning period, the NA and WA groups were statistically similar (p>0.05) but differed significantly from 12A in estradiol concentration. The highest FSH concentration (5.72 µ/L) was recorded in the 6A.
Conclusion: The mean concentrations of the hormones were found to be significantly influenced by the reproductive phases and aestivation treatments.
Keywords: Hormones, Archachatina marginata, aestivation, naturally controlled, reproductive phase