The Effects of Soybean Lecithin Supplementation to a Practical Diet Formulation on Juvenile Channel Catfish, Ictalurus punctatus: Growth, Survival, Hematology, Innate Immune Activity, and Lipid Biochemistry

Abstract

A feeding trial was conducted to determine the effects of soy lecithin supplementation on production performance of juvenile channel catfish, Ictalurus punctatus (mean ± SE; 5.8 ± 0 g). The basal diet consisted of a practical dietary formulation for channel catfish, containing 4.3% endogenous phospholipids (PL) from dietary ingredients, to which supplemental PL from soybean lecithin were added. The study diets were 1 control and 2 experimental diets to which 0, 2, or 4% supplemental lecithin was added, respectively. Soy lecithin inclusion did not affect survival, growth, feed consumption, whole‐body total lipid, innate immune response, plasma cholesterol or triglyceride concentrations, or hepatosomatic index. Feed conversion (gain/intake) improved in fish fed 4% supplemental lecithin compared with 0% lecithin. Whole‐body crude protein was greater in fish fed 2% supplemental lecithin compared with 0% lecithin, while 4% supplemental lecithin was intermediate. Phosphatidylcholine (PC) content was greater in fish fed 2 or 4% lecithin than 0% lecithin. Plasma concentrations of PC were inversely proportional to dietary concentrations. Liver glycogen was greater in fish fed 0% lecithin compared with 2 or 4% lecithin. Liver lipid and phospholipid were lower in fish fed 0% lecithin than 2 or 4% lecithin. The dietary phospholipid requirement, if any, of juvenile channel catfish for growth and survival is less than or equal to 4.3% (1.5% PC) of the diet. Feed conversion is improved in channel catfish fed diets supplemented with 4% soy lecithin (7.2% phospholipid; 5.1% PC), which might offset additional costs due to phospholipid supplementation. Dietary soy lecithin inclusion altered plasma and liver lipid composition, but it is unknown whether these effects can alter the ability of juvenile catfish to survive and grow under various conditions.

Lecithin‐containing bioemulsifier boosts growth performance, feed digestion and absorption and immune response of adult Nile tilapia ( Oreochromis niloticus )

“…Tissue protein in the present study was also increased with increasing Lysomax concentration. Similar results were also reported in channel catfish fed graded levels of dietary lecithin (Sink & Lochmann, 2014).…”

“…On the contrary, larger fish may not benefit from supplemental PL, due to their capacity to synthesize PL from dietary precursors (Poston, 1990). On the other hand, supplemental soy lecithin did not affect survival, growth rates and feed efficiency in fingerling and juvenile channel catfish (Sink & Lochmann, 2014; Stickney & Andrews, 1972).…”

“…The effects of supplemental emulsifiers including lecithin, lysolecithin, bile acids and phosphatidylcholine (PC), on the growth rates, feed digestion and absorption have been tried in marine fishes (Benedito‐Palos et al, 2008; Bergman et al, 2018; Feng et al, 2017; Fountoulaki et al, 2009; Liu et al, 2002), freshwater fishes (Azarm et al, 2012; Sink & Lochmann, 2014); and shrimp (Khan et al, 2018). Results indicated that these emulsifiers can improve fish performance, feed efficiency, survival and immune response.…”

Effects of dietary soybean lecithin oil on the immunoglobulin level and fat globule size of milk in lactating sows

“…Sun, Wu, Zhang, Yue, and Qi (2010) showed that the contents of total phospholipid and PC in eggs were significantly increased relative to the control group when 0.5%, 1.0%, 2.0% and 4.0% SL was added in laying hens. Sink and Lochmann (2014) reported that PC content was greater in catfish fed 2% or 4% lecithin than fed 0% lecithin. Additionally, SL is one of the sources of choline and fatty acids.…”

Channel catfish, Ictalurus punctatus, nutrition in the United States: A historical perspective

“…Some studies were a collaboration with economist/Center Director Dr. C. R. “Carole” Engle, who was running feeding trials with catfish to establish the most profitable production practices, and with the NWAC in Mississippi. Several trials were conducted involving the grow‐out of catfish, including investigating alternative feedstuffs (Engle, Kumar, Lochmann, Bosworth, & Thompson, ; R. Lochmann et al, ; R. T. Lochmann, Islam, Phillips, Adam, & Everette, ; Pugliese, Heikes, Engle, Bosworth, & Lochmann, ; Renukdas et al, ; Sink & Lochmann, ), prebiotics (Thompson, Lochmann, Phillips, & Sink, ), lipid sources (Faukner et al, , ; Sink & Lochmann, ; Suja, Lochmann, Sink, Phillips, & Chen, ), dietary protein and feeding frequency (Engle, Ruebush, Leyva, & Trimpey, ), and winter feeding (Bastola, Engle, Haukenes, & Freeman, ; Nanninga, Engle, Stone, & Goodwin, ). Research was also conducted on the nutrition of catfish fry (Sink, Lochmann, & Kinsey, ) and broodfish (Sink & Lochmann, ; Sink, Lochmann, Pohlenz, Buentello, & Gatlin, ).…”