Effect of feed ingredients on nutrient digestibility, waste production and physical characteristics of rainbow trout (Oncorhynchus mykiss) faeces.

• DOI: 10.1016/j.aquaculture.2023.739621
• Publication Date: 2023-04-27T20:42:45Z
• Authors: Satya Prakash; Roel M. Maas; Peter-Melvin M.M....; Fotini Kokou; Johan W. Schrama; Antony J. Prabhu ...
• Keywords: Digestion

This study assessed the effect of different dietary ingredients on quantity and characteristics faecal waste produced by rainbow trout (Oncorhynchus mykiss). Seven were tested: fish meal (FM), mussel (MM), poultry wet rendered (PM-W) or dry (PM-D), insect (IM), single cell protein (SCP) brewers grain (BGP). Eight experimental diets formulated: a control diet (CON) being predominantly plant-based seven test diets, which contained 70% CON 30% one ingredients. Rainbow juveniles (65 g, 30 fish/tank) fed at satiation for six weeks in triplicate groups. Dry matter (DM) nutrient digestibility measured. To estimate characteristics, particle size distribution (PSD) removal efficiency was determined. Nutrient differed significantly. Growth did not differ between but DM affected diet. Diets amount produced, its (%) non-removed faeces (g DM/kg feed). The highest lowest observed FM BGP respectively. Accordingly, resulted (37 g feed), while (125 feed) faeces. Additionally, it also that differences can compensate variation produced. Consistent with data, PSD influenced diets. MM proportion particles <40 μm size, had largest this range. Furthermore, ingredient composition evident stability faeces, producing most stable, whereas CON, SCP resulting relatively unstable pellets. In addition, due to inclusion level nutrients their corresponding digestibility, chemical Overall, showed influences is an important factor determining efficiency, PSD, trout.