Use of proteases (resource efficiency)

Last update: 2 June 2023

• Action: Enhancing digestion of dietary vegetable proteins.
• Animal category: Pig and poultry.
• Technique: Adding authorized proteases to feed, facilitating the substitution of highly digestible protein sources (soybean meal) with less digestible co-products (e.g. rapeseed meal) without increasing the total dietary protein level.
• Mode of action: Proteases increase the digestibility of amino acids.
• Potential efficacy: Increased apparent ileal amino acid digestibility in poultry (AIAAD) by 4 % on average.
• Nature of evidence of efficacy: Peer-reviewed scientific publications (meta-analysis); EFSA assessment.
• Factors impacting on efficacy: Nutrient profiles of feed ingredients (different amino acid composition and molecular weight); total protein level in the feed; the type of protease; age of the animal; presence of other enzymes (phytases, NSPases).
• Mode of use: Pre-treatment of the protein source (eg. soybean meal incubation with the protease product under optimal pH and temperature conditions) or adding the enzyme to the feed.
• Requirements/limitations: Must be added in a mixture by a registered feed business operator applying HACCP (Regulation (EC) No 183/2005); only proteases produced from non-GM microorganisms may be used in organic farming.
• Economic consequences: Increase in body weight (1.38%) and reduction in feed conversion ratio (–0.92%) observed for poultry; the use of lower digestibility protein sources reduces feed costs.
• Other considerations: Supplementing protease into diets already containing other enzymes (eg phytase) gives no improvement in AIAAD.
• References:
  • Lee et al. (2018). Meta-analysis: Explicit Value of Mono-component Proteases in Monogastric Diets. Poultry Science – Volume 97, Issue 6, 1 June 2018, Pages 2078-2085. https://doi.org/10.3382/ps/pey042
  • Bertechini et al. (2020). Amino acid digestibility coefficient values of animal protein meals with dietary protease for broiler chickens. PubMed Central (PMC). https://doi.org/10.1093/tas/txaa187
  • Leinonen et al. (2015) Effects of dietary protease on nitrogen emissions from broiler production: a holistic comparison using Life Cycle Assessment. Journal of the Science of Food and Agriculture – Volume 95, Issue 15, December 2015, Pages 3041-3046. https://doi.org/10.1002/jsfa.7202
  • EFSA opinions on safety and efficacy of proteases (various opinions)
• Other techniques: Use of highly digestible protein sources; use of phytase (release of N blocked by phytic phosphorous).