A deep litter system starts with 15 cm of straw or wood shavings and adds fresh bedding on top of the soiled layer instead of cleaning daily, letting the lower layers compost in place and warm the pen, with total depth reaching 30-60 cm before cleanout. Add bedding when the surface turns wet rather than on a fixed schedule, because weekly additions of 5-10 cm would reach the top of that depth in 5-9 weeks.
Part of Manure Management
A bedding system is the layer of straw, shavings or similar material that absorbs manure and urine and keeps animals dry, either replaced often or built up as deep litter.
Deep Litter Saves Labour By Replacing Cleaning With A Slow Compost Pack
Instead of cleaning daily, you add fresh bedding on top of soiled bedding. The bottom layers begin composting in place, generating heat. That reduces daily labour dramatically, provides warmth in winter (composting generates 40-50 °C at depth), and produces pre-composted material when it is cleaned out, 2-4 times a year. The system works only while the pack stays dry on top and aerobic underneath. A pack that goes wet and sealed turns anaerobic, and anaerobic manure makes hydrogen sulphide and ammonia.
What You Need
- Bedding: straw, wood shavings or similar dry, absorbent material
- A pen with a dry floor and good ventilation — see Ventilation Without Drafts and Shelter Requirements
- A fork and barrow, for cleanout
- A cloth mask, for working a dusty or moldy pack
Method: Manage The Pack
Step 1: Start at 15 cm. Lay 15 cm of fresh bedding over a dry floor.
Step 2: Add when the surface gets wet. Add 5-10 cm of fresh bedding whenever the surface becomes wet, or on a weekly cycle if you find it needed. Check by pressing a hand into the pack: it should be dry and springy on top.
Step 3: Watch the depth. Total depth can reach 30-60 cm before cleanout. Past that, the pack gets too deep to work.
Step 4: Clean out 2-4 times a year. Fork out the whole pack, leaving a thin layer of old bedding to seed the next. Move it to the composting area; see Collection & Composting.
Step 5: Check the smell. A pack that smells strongly of ammonia is too wet or too deep, or has too little ventilation. Add dry bedding and open the vents.
Worked Example
Depth against time. Start 15 cm. Adding 5 cm a week reaches the 60 cm upper limit after (60 − 15) / 5 = 9 weeks. Adding 10 cm a week reaches it after (60 − 15) / 10 = 4.5 weeks. To reach only the 30 cm lower limit takes (30 − 15) / 10 = 1.5 weeks up to (30 − 15) / 5 = 3 weeks.
Cleanouts 2-4 times a year are every 52 / 4 = 13 weeks up to 52 / 2 = 26 weeks. If you added 5 cm every week for 13 weeks the pack would be 15 + 13 × 5 = 80 cm, which is above the 60 cm limit. So a fixed weekly top-up of 5-10 cm cannot be combined with cleanouts only 2-4 times a year. Add bedding when the surface is wet, or clean out more often, and let the depth be set by how wet the pack is, not by the calendar.
Common Mistakes
- Fixed weekly additions — the depth overruns before the next cleanout.
- Letting it go wet and compacted — it turns anaerobic and gives off ammonia and hydrogen sulphide.
- Cleaning out in a closed building — forking a deep pack releases trapped gas and dust.
Safety
Gas and dust from a deep wet pack
A deep, wet, compacted pack, especially under a pen with little ventilation, generates hydrogen sulphide, ammonia, methane and carbon dioxide. Hydrogen sulphide is heavier than air and deadens the sense of smell at dangerous concentrations, so “I can no longer smell it” means it is getting worse, not better. Turning or forking out the pack releases a slug of gas: open every door and vent first, work with another person present, and leave at once if anyone feels dizzy, headachy or short of breath. Never climb into a pit or channel under a pen.
Moldy, dusty bedding can cause lung disease: wet it down and wear a cloth mask over the nose and mouth when forking it out. Do not test the air with a flame.
What’s Next
- Learn next: Collection & Composting — what to do with a cleanout
- Combine with: Straw and Hay — straw as insulation and bedding