Optimal water volume for transportation of male Siamese fighting fish (Betta splendens)

Abstract

The smallest water volume that humanely supports Siamese fighting fish (Betta splendens) during local transportation was determined. Mature male Siamese fighting fish (1.46 ± 0.01 body weight, n = 90) were individually packed in transparent bags containing different water volumes (40, 60, 80, 100, 120, and 140 mL) that gave a 1: 3 ratio of water to air. The packaging procedures followed the Thai Post Office’s standard. The fish were domestically transported to five different destinations and returned. The total duration of transit was approximately 48 h. On arrival back at the laboratory, the specimens were immediately harvested, and water quality, survival, morphometric changes, digestive enzyme activities, skin coloration, muscle quality, and whole-body composition were determined. The results were compared with a group (n = 15) that was not transported. Water pH, temperature, dissolved oxygen, alkalinity, and ammonia were significantly affected by water volume (P < 0.05). Survival and weight loss variation indicated against using water volumes of 40 or 60 mL (P < 0.05), although weight and length characteristics were similar to other treatments (P > 0.05). Fish transported in 80 and 100 mL of water showed similar characteristics for skin coloration and muscle quality (P > 0.05) but no difference in whole-body composition was observed between the two treatments compared to the control (P > 0.05). The findings of our study indicated that the minimal water volume that B. splendens tolerated well during transportation was 80 mL. This study can be used as a guide for local overland shipping of male Siamese fighting fish.