전복 혼합 사료 공급에 따른 전복 침 성장 및 다양한 스트레스에 대한 내성 평가. 본 연구에서는 전복 혼합사료에 어분과 해조류를 대체하는 발효대두박과 생미강을 각각 사용하여 전복의 성장과 다양한 스트레스에 대한 내성을 평가하였다. 실험식이의 효과를 평가하기 위해 미역(Undaria pinnatifida), 다시마(Laminaria japonica) 등 자연식을 제공하는 실험군을 구성하고, 모든 식이를 2회 반복하였다.
다양한 스트레스 조건(공기노출, 염도급격변화, 수온급격변화)에 노출되었을 때 16주 사육실험에서 살아남은 전복의 누적 폐사율을 측정하였다. 염도와 수온의 급격한 변화에 따른 전복의 누적 폐사율은 복합사료를 공급한 모든 플롯에 비해 천연사료를 공급한 플롯에서 상당히 높았습니다. 결론적으로, 자연식품을 공급한 실험군에 비해 복합사료를 공급한 실험군에서 전복의 성장이 더 좋았으며, 공기노출을 제외한 다양한 스트레스에 대한 내성도 전복사료를 공급한 실험군에서 더 높게 나타났다. 혼합사료를 먹였습니다. 자연식품을 제공받은 실험군보다 자연식품을 제공한 실험군에서 높은 것으로 나타났다.
키워드: 전복(Haliotis discus); 복합사료; 생선 음식; 해초; 스트레스 내성.
Experiment
Introduction
However, in Australia all abalone farms routinely feed using a formulated diet despite similar stressors (Bansemer et al. 2016). These stressors can suppress immunity of abalone and increase their susceptibility to disease (Edwards et al. Mortality of abalone can also occur in nature due to high environmental temperature and salinity changes (Takami et al. 2008, Park et al. 2013).
Few comparative data are available on the aquatic stability of formulated feed and the stress tolerance, growth or survival of abalone fed MA and formulated feed (Cho & Kim 2012, David et al. 2014). The most promising alternative feed ingredients for FM and MA are soybean meal (Uki et al. 1985, Lee et al. 1998, Cho et al. 2008a, Cho 2010) and rice bran, which are nutrient-rich byproducts of agriculture such as . crude protein and vitamins (Kim et al. 2016a). In addition, fermentation of soybean meal increases protein content, removes trypsin inhibitors, and reduces peptide size (Hong et al. 2004).
Oral administration of fermented soybean meal had a promising effect on performance of fish (Lim & Lee 2011, Zhou et al. 2011).
Materials and methods
- Preparation of abalone and rearing conditions
- Preparation of the experimental diets
- Growth measurements
- Proximate analysis of abalone flesh and water stability of nutrients in the
- Stress resistance of abalone subjected to the various stress conditions
- Statistical analysis
One hundred abalone at the start and fifty abalone from each tank at the termination of the feeding trial were sampled and frozen for analysis. Before examination, all samples were slightly thawed, followed by separation of the shell and soft body tissue. Shell length, width, and height were measured to a precision of 1.0 mm with a digital caliper (Mitutoyo Corporation, Kawasaki, Japan), and the ratio of soft body weight to whole body weight (the soft body weight + shell) was calculated to determine a condition index for abalone.
The total separated soft body tissue from sampled abalone from each tank was then homogenized and used for proximate analysis. These containers were then placed in a 5 ton concrete flow tank indoors at a flow rate of 45.6 L/min and subsampled at 72 hours and 72 hours to evaluate the leaching of dietary nutrients to determine their water stability. Nutrient levels in the diets were assessed using the same procedure described above for the abalone meat.
Stress tolerance of abalone under different stress conditions The different stress conditions of abalone were modified based on Cho et al. At the end of the 16-week feeding trial, sixty randomly selected abalones from the 12.5-ton tank were divided into 3.70 L plastic rectangular containers (120 cm × 36 cm) (twenty abalones per container). Twelve 70-liter plastic rectangular containers from each tank were randomly placed in a 1-ton fiber-reinforced plastic (FRP) inner tank, and 3.1-ton FRP tanks were used to withstand the loads of abalone exposed to various stressful conditions (exposure to air, sudden low temperature). salinity and high temperature changes).
The designated diets were fed abalone for two weeks to minimize handling stress to the abalone before being subjected to their stress tolerance test. Seawater in twelve containers of abalone in a 1 ton indoor FRP tank was completely drained and exposed to air for 30 h at room temperature. Twelve containers of abalone in another 1-ton indoor FRP tank at salinity 31 in natural seawater were moved to the second 1-ton FRP tank adjusted to salinity 25 by mixing with tap and seawater.
One-way ANOVA and Duncan's multiple test (Duncan 1955) were used to determine the significance of differences between treatments using SAS version 9.3 (SAS Institute, Cary, NC, USA). The water stability of the experimental diets was tested by repeated measures ANOVA (Cody & Smith 1991).
Results
- Water stability of the experimental diets
- Growth performance of abalone
- Proximate composition of the soft body of abalone
- Cumulative mortality of abalone subjected to various stress conditions · 19
Weight gain and SGR of abalone fed all formulated diets were also significantly (P < 0.05) higher than those of abalone fed the MA. The soft body weight of abalone fed all formulated diets was significantly (P < 0.05) greater than that of abalone fed the MA. The soft body moisture content of abalone fed the FM50 diet was significantly (P < 0.05) higher than that of abalone fed the FM50 + MA50 diet, U.
The crude protein content of the soft body of abalone fed the FM50 + MA100 diet was significantly higher (P < 0.05) than that of abalone fed all other diets. The crude protein content of the soft body of abalone fed the standard and FM50 + MA50 diet was also significantly higher (P < 0.05) than that of abalone fed the FM50 diet, L. The crude lipid content of the soft body of abalone fed the FM50+ MA100 diet was significantly higher (P < 0.05) that of abalone fed in all other diets.
The crude lipid content of the soft body of abalone fed the FM50 + MA50 diet was also 1 Specific growth rate (SGR) = [(Ln(Wf) - Ln(Wi))/feeding days]×100, where Ln(Wf) = natural log of mean final weight of abalone and Ln(Wi) = log natural average initial weight of abalone. Shell length (mm), shell width (mm), shell height (mm), soft body weight (g/individual) and the ratio of soft body weight to total weight of the flask fed the experimental diets for 16 week at the balloon farm.
Chemical composition (%) of the soft body of abalone at the end of the 16-week feeding trial on abalone farm. The cumulative mortality of abalone fed the MA (U. pinnatifida and L. japonica) and Standard and FM50 diets was significant (P. Poor weight gain and SGR were found in abalone fed the diets replacing 50% FM with the fermented soybean meal, regardless of replacement of MA (FM50, FM50 + MA50 and FM50 + MA100), compared to that of abalone fed the Standard diet.
The higher SGR in larger abalone at lower temperature in this study indicates that the growth rate of abalone (H. . discus) is faster than that of abalone (H. discus hannai). The higher protein and lower soft-body ash content of calves fed the formulated diets compared with those of calves fed MA was well reflected by the nutrient content of the experimental diets in this study, falling in agreement with other studies (Mai et al. The cumulative mortality of abalone fed the MA, Standard and FM50 diets was higher than that of abalone fed the FM50 + MA100 diet at 100 h after air exposure in this study.
Cumulative mortality of abalone fed MA was higher than that of abalone fed all other diets at 96 h after the sudden salinity change, but no difference in cumulative mortality was found between formulated diets. For example, survival of 2-year-old abalone (H. laevigate) fed a commercial diet or Ulva lactuca at 26°C was over 90%, but survival (65%) of 3-year-old abalone fed a commercial diet was lower. than that (90.2%) of abalone fed in U. The relatively higher cumulative mortality of abalone fed MA compared to all formulated diets before being subjected to various stress conditions in this study indicated that abalone of fed the formulated diets were more resistant to the various stress conditions commonly encountered during abalone culture throughout the year than MA on the farm.
