A Method to Analyze the Relationship Between Locomotor Activity and Feeding Behaviour in Larvae of Betta Splendens

The transition from live to artificial feed is a critical step for fish larvae with potential for cultivation. Determining the moment to initiate the introduction of artificial feed based on larvae swimming behaviour can reduce mortality levels resulting from this dietary transition. Kinovea® is a cost-free software used as a tool to study sports kinematics; its use can help to establish locomotor parameters to determine the best time to introduce artificial feed in Siamese fighting fish larvae diets, reducing the negative effects of weaning. The objective in this study was to evaluate the locomotor behaviour of Siamese fighting fish larvae under different feeding regimes using Kinovea® as a tool to study fish locomotor behaviour. A total of 234 larvae of Siamese fighting fish (Betta splendens) were used; they were divided into three dietary strategies (treatments): live feed, artificial feed and co-feeding. Each treatment had four replicates. The experimental units were video recorded for 1 min after feed was offered. It was observed that the weaning strategy resulted in higher zootechnical performance (p < 0.05). Larvae fed exclusively with live feed had higher swimming speed, and larvae fed with artificial feed displayed low velocity (p < 0.05). The results indicate that the use of artemia nauplii and high swimming speed are correlated. Based on the results, it is possible to conclude that the weaning strategy proposed in this study is efficient and that Kinovea® can be used as a software to access locomotor behaviour for fish larvae.