Chicken Feed Calculator

Poultry Nutritional Biochemistry, Amino Acid Ratios, and Feed Conversion Efficiency

Domestic chickens (Gallus gallus domesticus) possess a hyper-metabolic avian digestive anatomy characterized by a crop (storage and enzymatic pre-digestion), proventriculus (acidic stomach), gizzard / ventriculus (muscular grinding mill), and paired ceca (hindgut fiber fermentation).

Formulating a scientifically complete poultry ration requires balancing Crude Protein (CP), bioavailable amino acids (Methionine & Lysine), energy (metabolizable kcal/kg), and exact Calcium-to-Phosphorus ratios established by the National Research Council (NRC) Nutrient Requirements of Poultry.

Poultry Life Stage Nutritional Standards:
- Chick Starter (0–6 Weeks): 20% to 22% Crude Protein (Crumbled, 1.0% Calcium)
- Grower / Pullet (7–18 Weeks): 16% to 18% Crude Protein (1.0% to 1.2% Calcium)
- Active Laying Hens (19+ Weeks): 16% Crude Protein + 3.8% to 4.2% Calcium (Pellets/Crumbles)
- Broiler / Meatbirds (Finisher): 18% to 20% Crude Protein (High Energy Density)
Daily Feed Intake: Standard adult layers consume 110 to 130 grams (0.25 to 0.28 lbs) daily

The Vital Calcium Balance: Preventing Eggshell Failure & Kidney Gout

• Laying Hens (The 4% Calcium Mandate): Synthesizing a single eggshell requires 2.0 to 2.2 grams of pure calcium carbonate. If dietary calcium is below 3.5%, the hen's body strips calcium from her own leg and wing bones (cage layer fatigue / osteoporosis), leading to broken bones and soft rubbery eggs.
• Young Pullets & Roosters (The Kidney Toxicity Hazard): Never feed layer feed (4% Calcium) to chicks or growing pullets under 18 weeks old. Excess dietary calcium cannot be utilized before active eggshell formation and precipitates in the kidneys, causing fatal visceral gout and renal failure.

The Essential Role of Insoluble Granite Grit

Unlike mammals, chickens have no teeth. Food passes whole into the muscular gizzard, where ingested stones and grit act as teeth to grind whole grains, bugs, and fibrous grass into a digestible paste.

• Insoluble Granite Grit: Must be offered free-choice in a separate container (size-matched: chick grit for babies, grower grit for pullets, coarse granite grit for adults).
• Soluble Oyster Shell vs Insoluble Grit: Crushed oyster shell is soluble calcium that dissolves in stomach acid to build eggshells—it does NOT function as mechanical grinding grit in the gizzard. Hens need both.

The 10% Treat Ceiling: Preventing Fatty Liver Syndrome

Backyard chicken keepers frequently overfeed scratch grains, cracked corn, mealworms, and kitchen scraps. Corn is high in starch and low in protein (only 7–8% CP). Treats must never exceed 10% of total daily intake. Excessive scratch dilutes essential protein and triggers fatal Fatty Liver Hemorrhagic Syndrome (FLHS).

Calculate coop space with the Chicken Coop Size Calculator, track egg capacity using Egg Production Estimator, check nesting boxes via Chicken Nesting Box Count Calculator, and review poultry nutritional science at USDA NIFA.