Inclusion effect of jack mackerel,Trachurus japonicus, meal in the diet of rockfish,Sebastes schlegeli, on growth, feed utilization, biochemical composition, and innate immune responses

Abstract

Dietary inclusion effects of various levels of jack mackerel meal (JMM) on growth, feed utilization, biochemical composition, and innate immune response of rockfish were determined. The control (Con) diet included 550 g/kg fish meal (FM). Ten, 30, 50, 100, 200, 400, 600, and 1000 g/kg of JMM were included in the Con diet, referred to as the JMM10, JMM30, JMM50, JMM100, JMM200, JMM400, JMM600, and JMM1000 diets, respectively. Eight hundred and ten fish (initial mean weight of 2.3 g) were distributed into 27 flow‐through tanks. The experimental diets were assigned to triplicate groups of fish. Fish were hand‐fed for 8 weeks. Weight gain of fish fed the JMM400 diet was statistically better than that of fish fed the Con, JMM10, JMM30, JMM50, JMM100, and JMM200 diets. Feed consumption of fish fed the JMM400 diet was statistically higher than that of fish fed the Con, JMM10, JMM30, and JMM50 diets. Dietary inclusion of JMM did not influence feed utilization, biochemical composition, and innate immune responses of fish. In conclusion, inclusion of JMM up to 400 g/kg of FM in diet improved growth and feed consumption of rockfish, and dietary optimum inclusion levels of JMM were estimated to be 396.7 and 403.1 g/kg based on regression analysis of weight gain and feed consumption, respectively.

Impact on Growth and Feed Availability from Including Jack Mackerel (Trachurus japonicas) Meal in Rockfish (Sebastes schlegeli) Feeds Which Otherwise Replace Fish Meal with Chicken By-Product Meal

“…However, no statistical differences in growth, SGR, and feed intake of rockfish which were fed the C20J60 and C20J80 diets implied that the C20J60 diet appeared to be the most recommended dietary treatment in this experiment. However, incorporated JMM levels up to 40% in the 55% FM-based diet improved weight gain, SGR, and feed intake of rockfish; however, JMM inclusion levels higher than 40% (60% and 100%) did not improve further when juvenile rockfish were fed with a 55% FM-based diet or one of the diets which include 1, 3, 5, 10, 20, 40, 60, and 100% JMM at the cost of FM in the 56-day feeding experiment [19]. They also concluded that optimum inclusion levels of JMM were estimated to be 39.7 and 40.3% based on weight gain and feed consumption, respectively.…”

“…However, their attractiveness to fish varies greatly depending on fish species, feeding patterns, and the type and dosage of attractants [14,17]. Some feed ingredients in formulated fish feeds, such as tuna viscera hydrolysates and jack mackerel (Trachurus japonicas) meal (JMM), could improve feed intake [13,[17][18][19]. In particular, Chotikachinda et al [13] unveiled that the inclusion of 3-4% tuna viscera hydrolysates in the 54% poultry by-product meal-based diet enhanced feed palatability and increased the feed consumption and growth of Asian sea bass.…”

“…As the second-highest cultured marine fish species, its aquaculture production reached 16,189 metric tons in Korea in 2022 [27]. With the widespread cultivation of rockfish in the Eastern Asia, many nutritionists are paying attention to development of the rockfish feeds [19,22,[28][29][30][31][32][33][34]. The growth and feed intake of rockfish improved with increased incorporation levels of JMM from 0% to 40% at the expense of FM in diets, and optimum inclusion levels of JMM in diets were estimated to be 39.7 and 40.3% of FM based on weight gain and feed intake, respectively [19].…”

“…With the widespread cultivation of rockfish in the Eastern Asia, many nutritionists are paying attention to development of the rockfish feeds [19,22,[28][29][30][31][32][33][34]. The growth and feed intake of rockfish improved with increased incorporation levels of JMM from 0% to 40% at the expense of FM in diets, and optimum inclusion levels of JMM in diets were estimated to be 39.7 and 40.3% of FM based on weight gain and feed intake, respectively [19]. The highest feeding attractant response of rockfish was also noticed in JMM among 16 crude protein sources [29].…”

Substitution effect of fish meal with various plant protein sources on growth performance and feed utilization in rockfish (Sebastes schlegeli) diets including jack mackerel meal used as feed stimulants

“…In addition, 21.5% of wheat flour and 4.5% of each fish and soybean oils were contained as carbohydrate and lipid sources in the Con diet, respectively. In the Con diet, 25% and 50% FM were substituted with CGM, SPC, and CPC, respectively, and then 22% JMM, achieving the best growth and highest feed consumption of rockfish (Kim and Cho, 2023), was added at the sacrifice of FM in all plant-substituted diets, named as the CGM25, CGM50, SPC25, SPC50, CPC25, and CPC50 diets, respectively. All experimental feeds met the dietary protein and lipid requirements of rockfish (Cho et al, 2015).…”