# Research note: Nutritive value of cold-pressed flaxseed meal for broiler chicken

## TL;DR

This study compares the nutritional value of cold-pressed flaxseed meal to soybean meal for broiler chickens, finding that flaxseed meal has lower digestibility and energy content.

## Contribution

The study provides new data on the amino acid digestibility and energy value of cold-pressed flaxseed meal as an alternative feedstuff for poultry.

## Key findings

- Cold-pressed flaxseed meal has lower standardized ileal digestibility of most indispensable amino acids compared to soybean meal.
- Flaxseed meal has lower apparent retention of gross energy and nitrogen than soybean meal.
- Flaxseed meal has lower metabolizable energy content than soybean meal, likely due to higher fiber content.

## Abstract

A study was conducted to evaluate standardized ileal digestibility (SID) of amino acids (AA) and N-corrected apparent metabolizable energy (AMEn) values of cold pressed flaxseed meal (CPFM) for broilers. One hundred and twenty broiler chicks were divided into 20 groups of 6 birds/group and fed 2 diets in a completely randomized design (10 groups/diet) from 14 to 21 d of age. The diets were cornstarch-based containing CPFM or conventional soybean meal (SBM; reference feedstuff) as the sole protein source. A N-free diet fed in another study conducted in the same facility and at the same time that the current study was conducted was used to estimate basal endogenous AA losses, and to calculate gross energy retention by difference method. The CPFM had greater neutral detergent fiber and ether extract contents (21.40 vs. 8.18% and 20.4 vs. 2.47% as is, respectively), but lower CP (20.47 vs. 48.28% as is) than SBM. The SID values of all indispensable AA (except for Leu, Phe and Trp) for CPFM were lower (P < 0.05) than those for SBM. The apparent retention of gross energy (65.95 vs. 44.24%) and N (55.53 vs. 9.79%), and AMEn (2,699 vs. 2,491 kcal/kg) for CPFM were lower (P < 0.05) than those for SBM. In conclusion, CPFM can serve as alternative oilseed co-product feedstuff for poultry. However, the CPFM has lower SID of AA and AMEn values than SBM likely due to the greater fiber content in the former than in the latter.