Wheat germ as an alternative ingredient to a fair average quality fishmeal in diets for European seabass

Abstract

Wheat germ (WG) is a by‐product of the flour milling industry and could be a sustainable ingredient to replace a fair average quality fishmeal (FM) in aquafeeds. Subsequently, three diets were tested in European seabass juveniles (IBW: 16.7 ± 2.8 g): control diet without WG (CTRL); two diets with 75 g/kg and 155 g/kg WG (WG8 and WG16, respectively) at the expense of FM. Diets were isoproteic (500 g/kg dry matter, DM) and isoenergetic (21 MJ/kg, DM). After 18 weeks of feeding, apparent digestibility coefficients (ADCs) were determined and growth performance evaluated. Intestine and muscle were collected for histology and fatty acid profile, respectively. Innate immune parameters were evaluated in plasma. DM, protein and phosphorous ADCs increased concomitantly with the inclusion of WG; WG16 reached significantly higher values (p < 0.05) than CTRL. Feed conversion ratio was lower in fish fed WG16 than in those fed CTRL (1.5 vs. 1.6), while protein efficiency ratio increased with WG inclusion (1.4 vs. 1.2). Results demonstrate WG's potential to partially replace a fair average quality FM in diets for European seabass juveniles without impairing growth and body composition. WG inclusion at 16% (WG16) improved protein ADC and feed utilization, resulting in the lowest economic efficiency ratio, ECR (€/kg fish).

Seeking the best alternatives:Asystematic review and meta‐analysis on replacing fishmeal with plant protein sources in carnivorous fish species

“…Acccordingly, many studies have been conducted on plant protein sources, including soybean, 9–15 cottonseed, 15–18 rapeseed, 15,19–22 and lupin 23,24 . However, most of the studies were conducted by supplying one type of plant protein to single fish species such as Rainbow trout ( Oncorhynchus mykiss ), 25,26 Atlantic salmon ( Salmo salar ), 27,28 seabass species, 29,30 and catfish species 31,32 . Although a small proportion of articles have reported on the comparison between different protein sources, 33,34 and have analysed the effects of plant protein sources on multiple species, 35 to the best of our knowledge, no research has comprehensively evaluated the effects of replacing FM with various plant protein sources on different species.…”

Growth, Biochemical Characteristics, Flesh Quality, and Gut Microbiota of the Pacific White Shrimp (Penaeus vannamei) Fed a Defatted Superworm (Zophobas atratus) Larvae Meal

“…However, the expansion of shrimp production, the deterioration of the marine environment, and the reduction in fishery resources have led to a decrease in fish meal production and an increase in prices. Therefore, the search and development of alternative protein sources based on renewable natural resources is an urgent need for the sustainable development of the aquafeed industry [7][8][9][10].…”

Rapeseed proteins as fishmeal alternatives: A review

“…These desired attributes remain unchanged until today and multiple protein sources of plant origin have been investigated as fishmeal replacements in different species of fish due to their global availability and low market prices 2 over the past decades. These alternative plant proteins included sources from corn, 15–17 lupine, 18–20 pea, 21–23 rapeseed, 24–26 soy, 27–29 sunflower, 30–32 wheat 33,34 and others. Today it is commonly recognised that not a single protein source but rather a mixture of different protein sources will be able to replace fishmeal in aqua feeds completely 35 .…”