Growth, Reproductive Performances, and Brood Quality of Long Snout Seahorse, Hippocampus guttulatus, Fed Enriched Shrimp Diets

Abstract

This investigation examined the effect of using enriched shrimp (Atlantic ditch shrimp, Palaemonetes varians) diets on growth of long snout seahorse, Hippocampus guttulatus, and its effect on the reproduction rate and brood quality. Three diets were (1) natural wild‐caught shrimp (natural shrimp diet‐control diet), (2) wild‐caught shrimp fed an artificial feed for 10 d (enriched shrimp diet), and (3) wild‐caught shrimp fed one large meal of artificial diet and immediately frozen (ingested artificial feed shrimp diet). These diets were fed to seahorses during a 12‐wk growth trial. At the end, significant differences on the final wet weight were found between seahorses fed the three different treatments (P < 0.009). Seahorses fed ingested artificial feed shrimp diet had more broods (9), generated more juveniles per brood (299 ± 87), and significantly bigger juveniles (12.4 ± 1 mm) than seahorses fed natural shrimp diet and enriched shrimp diet. Significant differences in the morphometry of juveniles hatched from parents fed the three different dietary treatments (Wilk's λ = 0.2, F(6,460) = 47.41, P < 0.0001) were also found. Results indicate that the combined use of a natural diet (shrimp) and an artificial diet benefit growth and feed utilization by seahorses and have a direct impact on the reproductive rate and brood quality of H. guttulatus.