Anais da Academia Brasileira de Ciências (Sep 2008)
The importance of feeding in the larval development of the ghost shrimp Callichirus major (Decapoda: Callianassidae)
Abstract
The present study investigated whether the callianassid Callichirus major shows a lecithotrophic behaviour during larval development. Two experiments were carried out. In the first experiment, larvae were subjected to an initial period of feeding, while in the second they were subjected to an initial period of starvation. In Experiment 1, 80% of C. major larvae succeeded moulting to juvenile stage in treatment with larvae fed every day. In the treatments with larvae fed for 1, 2 and 3 days there was total mortality before they reached the megalopal stage. In Experiment 2, zoea larvae showed more resistance when subjected to an initial period of starvation in which larvae starved for 1, 2 and 3 days and had survival rates of 100, 60 and 80%, respectively. But, a delay in the development duration of the zoeal stages was observed. Total mortality was observed for larvae reared in the treatment with entire starvation. The results suggest that zoeal stages of C. major are not lecithotrophic.O presente estudo investigou se o callianassid Callichirus major apresenta um comportamento lecitotrófico durante o desenvolvimento larval. Dois experimentos foram realizados. No primeiro experimento, larvas foram submetidas a um período inicial de alimentação, enquanto no segundo elas foram submetidas a um período inicial de inanição. No experimento 1, 80% das larvas de C. major mudaram com sucesso para o estágio de juvenil no tratamento com larvas alimentadas diariamente. Nos tratamentos com larvas alimentadas por 1, 2 e 3 dias, houve uma mortalidade total antes de alcançarem o estágio de megalopa. No experimento 2, as larvas zoés mostraram mais resistência quando submetidas a um período inicial de inanição. Nos tratamentos nos quais as larvas estiveram em inanição por 1, 2 e 3 dias, as taxas de sobrevivência foram100%, 60% e 90%, respectivamente. Porém atrasos na duração do desenvolvimento dos estágios de zoés foram observados. Houve mortalidade total para as larvas cultivadas no tratamento com ausência constante de alimento. Os resultados sugerem não existir um comportamento lecitotrófico nas zoés de C. major.
Keywords
