Effects of environmental light colors on the larviculture of the Amazon River prawn Macrobrachium amazonicum

Abstract

This study aimed to investigate the effects of red, yellow, green, violet, blue, and white light in Macrobrachium amazonicum larviculture. The trials were composed of six treatments (i.e., colors red, yellow, green, blue, violet, and white light in tanks) with four replicates each. Transparent tanks of 1 L of water, 10 salinity, and 2400 newly hatched larvae were used in trials. The larvae were fed Artemia salina nauplii and complemented with commercial shrimp feed daily. The light color affected the temperature, pH, and dissolved oxygen in the water culture and nauplii consumption, survival, and productivity of M. amazonicum. In the tanks with red light, the mean temperature was lower, while the oxygen and pH levels were higher than those with other colors. The mean consumption of A. salina nauplii was 15% higher by M. amazonicum in tanks with blue and violet light than red light. No difference in larval development was observed; however, larvae cultured under white light completed the larval cycle four days earlier than those cultured under red light. The productivity of larvae cultivated under white and violet light was 45% greater than larvae cultured under red light, and the survival was > 75%. Results indicated that M. amazonicum larval cultivation should be performed in tanks under bright light, preferably white, since other colors may negatively affect the larval development.