Apparent Faecal Digestibility of Essential Amino Acids from Ω3 Pufa Diets for Laying Hens

Abstract

The apparent faecal digestibility of the essential amino acids from Ω3 PUFA layer diets and feeding solutions to avoid possible adverse effects of such diets were investigated in two experiments conducted on Lohmann Brown laying hens. Experiment 1 used 72 layers assigned to three groups (C1, E1-1, E2), while experiment 2 used 96 layers assigned to four groups (C2, E1-2, E3, E4). All experimental diets have been enriched in Ω 3 PUFA by supplementing a conventional diet (C1, C2) with 5% flaxseed meal and 2% camelina meal. Diets E2 and E4 had an increased level of Cu (150 mg/kg), diets E3 and E4 were supplemented with 0.0125% enzyme mix, while diets E1-1 and E1-2 were only supplemented with 5% flaxseed meal and 2% camelina meal. The digestibility coefficients of the studied essential amino acids (threonine, valine, phenylalanine, isoleucine, leucine, lysine, cystine, methionine) were lower (p≤0.05) in groups E1-1 and E2 from experiment 1, than in the control group (C1). In experiment 2, the supplemental enzyme mix (E3) increased (p≤0.05) the digestibility coefficients of phenylalanine, lysine, cystine and methionine, compared to the diet with camelina and flaxseed meals (E1-2). The simultaneous inclusion of copper and enzyme mix in the E4 diet increased (p≤0.05) lysine digestibility compared to group E1-2 and sulphur amino acids digestibility, compared to the other groups (C2, E1-2 and E3). In both experiments, only the feed conversion ratio was different (p≤0.05) in favour of the control groups (C1 and C2), compared to the other groups.

Xylanases in diets with alternative feeds and energy reduction in commercial layers

“…This result indicated that XP was effective in increasing the protein metabolizability of diets, possibly by reducing anti-nutritional factors (NSP) in corn and soybean meal. By hydrolyzing NSPs, xylanase allows the unavailable protein to be digested and amino acids to be absorbed, improving the MCCP (Varzaru, Panaite, Cornescu, & Olteanu, 2019). The metabolizability of proteins is directly influenced by the NSPs present in diets; therefore, by catalyzing dietary arabinoxylans, the enzyme allows amino acids, previously encapsulated in the cell walls of corn and soybean meal, to become readily available to perform the action of endogenous proteases, reducing endogenous production, which may be a secondary result of the xylanase response (Yaghobfar & Kalantar, 2017).…”