Combined effects of feeding enriched rotifers and antibiotic addition on performance of striped trumpeter (Latris lineata) larvae |
| |
| Institution: | 1. Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea;2. Département des Sciences, Université Sainte-Anne, Church Point, NS B0W 1M0, Canada;3. Marine Environment Research Division, National Institute of Fisheries Science, Busan 46083, South Korea;4. Graduate School of Fisheries and Environmental Sciences, Nagasaki University, Nagasaki 852-8521, Japan;5. Organization for Marine Science and Technology, Nagasaki University, Nagasaki 852-8521, Japan;6. Department of Marine Ecology and Environment, College of Life Sciences, Gangneung-Wonju National University, Gangneung 25457, South Korea |
| |
| Abstract: | Striped trumpeter have a complex and extended larval phase and are difficult to culture. Two experiments were conducted in replicated, 300-l hemispherical tanks to determine if larval survival, growth, bacterial or fatty acid profile were improved by feeding non-enriched rotifers or rotifers enriched with algae or commercially available products, as well as the effect of an antibiotic, oxytetracycline (OTC). Larvae were stocked at 25 l? 1 and 15 l? 1 and reared until Day 16 and Day 19 in Experiments 1 and 2, respectively. In Experiment 1, the feeding treatments were non-enriched rotifers, or rotifers enriched on algae, DHA Selco (a fish oil based emulsion) or RotiMac (dried Schizochytrium). There were no significant differences in mean survival (± SD) across treatments, which were generally low at 14.6 ± 5.2%. Larvae reared on rotifers fed DHA Selco and RotiMac, had significantly higher proportions of incorporated DHA but no significant increase in growth. In Experiment 2, larvae were fed rotifers enriched on DHA Selco or AlgaMac 2000 and reared with or without the daily addition of 25 mg l? 1 OTC. At Day 19, there was significantly higher survival for larvae reared on AlgaMac 2000 and OTC, (37.4 ± 5.6%), than DHA Selco and OTC, (16.0 ± 7.4%), AlgaMac 2000 without OTC (7.0 ± 8.0) and DHA Selco without OTC (3.3 ± 1.2). Larvae reared with OTC were larger (279 ± 58 μg and 7.4 ± 0.2 mm) than without OTC (177 ± 40 μg and 6.3 ± 0.2 mm). The addition of antibiotics did not significantly influence fatty acid profiles of larvae. There were no significant differences in the percentage of DHA, 27.6 ± 2.8%, EPA 4.6 ± 1.0% or ARA 4.9 ± 0.4%. Larvae reared with OTC had significantly less ‘grey gut’ (a measure of intestinal dysfunction). The results indicated that bacterial infection was a major source of mortality in striped trumpeter larvae and compromised larval growth. Assessment of the bacterial flora indicated that antibiotic use reduced the bacterial load, but did not eliminate potential pathogens. Our study suggests that microbial control has a greater influence than lipid nutrition on the survival and growth of larvae during the rotifer feeding stage. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
