Comprehensive Guide to Feeding Grit to Pasture-Raised Chickens, Turkeys, and Poultry

This article originally appeared in APPPA Grit issue 83 (September/October 2014) by Nathan Boggs. Edited for presentation on the web.

Lack of grit can result in as much as 20% greater feed consumption.

Poultry which are fed grit have gizzards which are as much as 50% larger than those not fed grit. This results in a more powerful masticating muscle and, consequently, better digestion.

Grit requirements vary depending on poultry species, soil type, feed type/grain size, and forage type/quantity/size.

Cost

Gran-i-Grit currently costs $78.50/ton ($0.04/lb. or $1.96/50 lb. bag). Prices are rounded for clarity and are based upon current Gran-i-Grit direct sales prices.

Layers

Each will consume 1/6-1/3 lbs. of grit per month (2 to 4 lbs./yr.). Highest consumption is in early winter and when new feathers are being formed. Lowest consumption is in spring and summer.

Budget one to two tons of grit per year for a flock of 1,000 Layers (between $78.50 and $157 for each 1,000 Layers/yr.).

 On average, grit results in 7% to 9.6% greater egg production coupled with a 6.3% to 7.1% decrease in feed consumption. The highest percentage improvements are made by feeding both insoluble grit (granite) and soluble grit (oyster shells or limestone). For the purposes of this document, “grit” refers to “insoluble granite grit.”

 Grit intake also results in thicker egg shells and an overall increase in flock health.

Soluble grit consumption varies depending on egg production. Higher lay rate equals more soluble grit consumed. Consumption averages 0.64 oz./layer/week or 2.08 lbs./layer/yr.

Broilers

Each will consume up to 1/20th their diet in grit. Therefore, a bird eating 12 to 14 lbs. of feed over the course of its life will eat up to 0.6 to 0.7 lbs. of grit.

Budget as much as 60 to 70 lbs. of grit for every 100 Broilers ($2.36 to $2.75/100 Broilers).

Grit intake results in better feed conversion/weight gain of up to an additional one pound per broiler and an overall increase in flock health.

Turkeys

Turkeys can consume the equivalent of 1/5th their diet in grit. Therefore, a bird which eats 60 lbs. of feed in its lifetime will likely consume approximately 12 lbs. of grit if given the opportunity. Over the course of their life, they may even consume the equivalent of their carcass weight in grit.

Budget 12 to 16 lbs. of grit per turkey for a flock projected to average 16 lbs. dressed weight ($0.47 to $0.63/turkey).

Grit intake results in better feed conversion/weight gain and an overall increase in flock health.

Grit Feeding Guide

Feed the largest size grit which your birds will eat in normal quantities. If a flock eats too much grit, change to the next larger particle size.

 Feed grit free choice. Poultry will only eat as much grit as they need. Offer grit either by itself or mixed with feed or whole grains such as wheat (recommended grit:wheat ratio or 1:4).

Generally, if mixing grit into feed rations, add at a rate of .5% to .75% of total ration.

Grit Feeding Schedule

Chicks and poults can mistake grit for feed with damaging results. Help them establish correct feeding habits by sprinkling grit over their feed for the first two days. After that, offer grit free choice in separate hoppers. Alternatively, avoid all grit on days for the first two days and begin feeding it on day three.

 Layers:

• Starter: Weeks 1-3
  
• Grower: Weeks 4-7
  
• Developer-Layer: >Week 7
  

Broilers:

• Starter: Weeks 1-2
  
• Grower: Weeks 3-6
  
• Developer/Layer: >Week 6

 Turkeys:

• Grower: Weeks 1-3
  
• Developer-Layer: Weeks 4-8
  
• Turkey: Weeks 9-14
  
• Turkey Finisher: >Week 15

 Waterfowl:

• Grower: Weeks 1-3
  
• Developer-Layer: Weeks 4-8
  
• Turkey: Weeks 9-14
  
• Turkey Finisher: >Week 15