Efecto de la espirulina (Arthrospira platensis) (Oscillatoriales: Cyanobacteria) en la cría experimental de Pseudosuccinea columella (Basommatophora: Lymnaeidae)

Abstract

<p>Snails of the family Lymnaeidae, as <em>Pseudosuccinea columella</em>, are the intermediate hosts of <em>Fasciola hepatica</em>, the causative agent of fasciolosis in human and livestock all over the world. A thorough knowledge of snail biology is essential for describing the transmission dynamics and for controlling this disease. Since food quality has had a significant effect on snail growth, fecundity and fertility, in this study we evaluated the use of spirulina (<em>Arthrospira platensis</em>) as a food resource for the artificial breeding of <em>P. columella</em>, an invasive snail and the main intermediate host of <em>F. hepatica</em> in Northeastern Argentina. The main purpose was to measure the effect of spirulina on fitness parameters such as survival rate, growth rate, size at first reproduction, lifetime fecundity and viable offspring. A total of 20 676 newly-laid F₂ eggs were used; half of them were fed with lettuce (treatment L) and the other half with lettuce plus spirulina (treatment L+S). In comparison with <em>P. columella</em> snails fed only with lettuce, we found that <em>P. columella</em> fed with lettuce plus spirulina: <strong>1)</strong> showed higher survival rates, <strong>2)</strong> grew faster and showed higher growth increments, <strong>3)</strong> attained sexual maturity earlier in time (L+S:60 days vs. L:120 days) and at a smaller size (L+S:4.8mm vs. L:8.2mm), <strong>4)</strong> had a longer reproductive period (L+S:150 days vs. L:90 days), <strong>5)</strong> produced a higher number of eggs/snail (L+S:29.6 vs. L:13.3), and <strong>6)</strong> showed a higher offspring hatching rate (L+S:70% vs. L:40%). The supplementation of <em>P. columella</em> diet with commercial spirulina enhances it fitness and improved the artificial breeding of this species. Spirulina may have a direct positive effect on <em>P. columella</em> development by consuming it, along with an indirect positive effect by improving the water quality. This rearing technique provided large number of reproducing adults and a continuous production of offspring, which are essential for developing future experimental studies in order to improve our knowledge on <em>P. columella</em> biology.</p>