Poultry Nutrition Guide: Feed Requirements & Dietary Science
A comprehensive guide to poultry dietary requirements, metabolizable energy, amino acid balance, and mineral nutrition for commercial flocks.
Scientific Overview
Poultry nutrition is the applied science of formulating feeds that precisely meet the biological requirements of growing, laying, and breeding birds. Feed accounts for 60–70% of total production costs, making nutritional precision the single most impactful lever for profitability. This guide covers the essential principles of energy, protein, amino acids, vitamins, and minerals in commercial poultry diets.
Metabolizable Energy (ME) in Poultry Feed
Metabolizable Energy (AMEn) is the primary energy currency in poultry nutrition. It represents the gross energy of feed minus the energy lost in feces, urine, and gaseous combustion — corrected for nitrogen retention (n).
- Broiler Starter requirement: 2,950–3,050 kcal AMEn/kg
- Broiler Grower requirement: 3,050–3,150 kcal AMEn/kg
- Layer requirement: 2,700–2,800 kcal AMEn/kg
When energy is too low, birds consume more feed to satisfy their energy needs, elevating FCR. When energy is too high without corresponding protein balance, fat deposition increases and meat quality declines.
Protein and Amino Acid Requirements
Modern poultry nutrition does not use crude protein as the primary specification. Instead, it focuses on digestible amino acids — specifically Lysine as the first limiting amino acid, around which all others are balanced using the Ideal Protein Profile:
- Digestible Lysine: Set at 100% (the reference amino acid)
- Methionine + Cystine: 74% of Lysine
- Threonine: 65% of Lysine
- Tryptophan: 18% of Lysine
- Valine: 80% of Lysine
Formulate precise amino acid-balanced diets using the Feed Formulation Mixer.
Vitamins and Minerals in Poultry Feed
Key micronutrients and their roles in commercial poultry:
- Calcium (Ca): Critical for skeletal formation and eggshell calcification. Deficiency causes rickets in broilers and thin shells in layers.
- Phosphorus (P): Must be supplied as 'available P' (phytate-bound P is unavailable without phytase enzyme). Ca:P ratio of 2:1 is optimal for broilers.
- Vitamin D3: Required for calcium absorption from the gut. Deficiency leads to leg disorders (rickets, angular bone deformity) in broilers.
- Vitamin E + Selenium: Antioxidant duo protecting cellular membranes. Deficiency causes Exudative Diathesis and Encephalomalacia.
- Sodium, Potassium, Chloride (electrolytes): Regulate fluid balance, acid-base status, and feed/water intake. Heat stress rapidly depletes electrolytes.
All scientific data, diagnostic criteria, and performance benchmarks presented on this page are derived from published peer-reviewed journals and official veterinary codes:
- Avian Pathology & Diagnostics: World Organisation for Animal Health (WOAH, 2023). Manual of Diagnostic Tests and Vaccines for Terrestrial Animals. Paris, France.
- Poultry Diseases & Histology: Swayne, D.E., et al. (2020). Diseases of Poultry (14th ed.). Wiley-Blackwell / American Association of Avian Pathologists.
- Nutrition & Feed Chemistry: Leeson, S. & Summers, J.D. (2001). Commercial Poultry Nutrition (3rd ed.). University Books, Guelph, Ontario.
- Commercial Breed Standards: Aviagen (2024). Ross 308 & Cobb 500 Broiler Performance Objectives. / Lohmann Breeders (2024). Lohmann Brown Management Guide.