Amphipods as Effective and Viable Live Feed for Juvenile Seahorses

Ornamental aquaculture has shown significant growth, contributing to species conservation and reducing the pressure of wild harvesting on natural stocks. In Brazil, populations of the seahorse Hippocampus reidi are in decline due to environmental degradation and capture for trade. Cultivation of this species has emerged as an alternative to reconcile conservation and commercial interests, but feeding remains a major challenge. Seahorses naturally prey on amphipods, which offer good nutritional quality, low production cost, and potential as an alternative live feed. In this study, two amphipod species (Cymadusa filosa and Parhyale hawaiensis) were tested as a monospecific diet for H. reidi, in comparison to Artemia (Artemia salina). Additionally, C. filosa was cultivated with either algae (Sargassum filipendula) or formulated feed to assess the influence of diet on its nutritional quality and the resulting performance of seahorses. Results showed that amphipods, even when consumed in smaller quantities, promoted greater weight gain, specific growth rate, and feed efficiency compared to Artemia. The observed benefits may be related to the superior nutritional composition of amphipods, especially in terms of essential fatty acids. No significant differences were found between the tested amphipod species or between the diets offered to C. filose, suggesting both factors are suitable and promote similar growth and efficiency. However, C. filosa stands out due to its higher fecundity, lower mobility and ease of culture with formulated feed, favoring its application in ornamental aquaculture. This study indicates that the use of amphipods, especially C. filosa reared on formulated feed, represents a viable, efficient, and sustainable alternative for feeding H. reidi, contributing to the development of cultivation protocols for the conservation of the species.

观赏水产养殖已呈现显著增长态势，既助力物种保护，也缓解了野生捕捞对自然种群的生存压力。巴西海域的里氏海马（Hippocampus reidi）种群因环境退化及贸易捕捞而持续下降，该物种的人工繁育已成为协调保护与商业利益的可行方案，但投喂问题仍是一大核心挑战。海马天然以端足类（amphipods）为食，这类生物不仅营养品质优异、养殖成本低廉，同时也是极具潜力的替代鲜活饵料。本研究选取两种端足类——丝状异钩虾（Cymadusa filosa）与夏威夷钩虾（Parhyale hawaiensis），将其作为单一种类饵料投喂里氏海马，并与卤虫（Artemia salina，Artemia）的投喂效果进行对比。此外，本研究分别以马尾藻（Sargassum filipendula）与配合饲料作为培育饵料来养殖丝状异钩虾，以探究饵料对其营养品质以及后续海马养殖表现的影响。实验结果表明，相较于卤虫，即便投喂量更低，端足类饵料仍可显著提升里氏海马的增重率、特定生长率与饲料利用效率。上述优势可能与端足类更优异的营养组成相关，尤其是其必需脂肪酸含量更为突出。供试的两种端足类之间，以及以不同饵料培育的丝状异钩虾之间，均未出现显著差异，这表明二者均为适配的饵料来源，可实现相近的养殖生长与饲料利用效率。但丝状异钩虾因其繁殖力更强、活动能力更低，且更易通过配合饲料进行规模化养殖，因此在观赏水产养殖场景中更具应用优势。本研究证实，使用端足类饵料——尤其是以配合饲料培育的丝状异钩虾——可作为里氏海马投喂方案的高效、可持续且可行的替代选择，有助于推动该物种保护相关繁育规程的完善与发展。