The low-smell, warm & cosy chicken coop

Provided by New Zealand Lifestyle Block, incorporating Growing Today, magazine.

Manage your coop's floor litter well and you can create a low-smell warm coop and harvest a fantastic compost at the end of the year.

Take a bit of science, mix it with a bit of chicken manure and some wood shavings and you can create a floor litter in your coop that has almost no smell, generates heat and turns into a beautiful compost.

Deep litter is a term used to describe the floor of a poultry house that has a layer of litter material that gradually builds up from an initial base of some sort of loose, dry material, usually wood shavings. Mixed with the birds' manure and additional dry litter as required, it will not need removing for at least six months and can stay "good" for up to 12 months if it is looked after and keeps 'working'.

The deep litter concept uses bacteria to heat and break down the incoming manure so it remains virtually smell-free, healthy and becomes an ideal fertiliser.

The concept of deep litter was started in the 1940s-1950s when it was found bringing poultry flocks inside permanently all year round had the advantages of keeping the birds warmer in winter, free from predators, protected from diseases carried by wild birds, pests and humans (!), better feed efficiency, and better all-year-round egg production when used in conjunction with artificial lighting to create a constant day length.

Over the decades the commercial poultry industry has refined the system so it is either all litter or a combination of litter and slatted areas. Birds housed in these sort of houses are often referred to as 'barn-raised'

In a well-managed deep litter house the shed is not cleaned out at all during the period the birds remain there. In a rearing shed for chicks this would be a period of 16-18 weeks, and in a laying shed usually a period of 60-80 weeks. At the end of 60-80 weeks a well-managed deep litter bed will be about 20-30cm deep, just dry, and a dusty, excellent fertiliser.

Meat chickens or broilers are also kept in barn-type conditions on deep litter in a similar manner, but for a much shorter period so the litter does not become as deep.

Properly managed deep litter is the key, and it doesn't just happen. Any wet areas due to overflowing drinkers, weather or spillage must be removed.

A build-up of droppings in a particular area, for instance under perches, needs to be spread and integrated with the dry areas.

Ventilation is also critical. If a shed is shut up in winter to conserve heat it also raises the humidity from the birds' breath and droppings, dampening the litter and causing the surface to cake. Fresh air and a dry atmosphere are essential.

How to create a deep litter bed

Have the litter deep from the start

You need to have the litter material - ideally dry wood shavings - at least 10cm deep. If your shed or coop has a concrete floor (which is cold) you will need an even deeper bed of litter to start with.

If the litter is too shallow the microbes that break the faeces down do not get warm enough to "work" the litter, and freshly-added droppings need to have the moisture absorbed by the litter for optimum composting.

Use wood shavings

Shavings are better than sawdust because there is not enough air between sawdust particles. Sawdust forms a surface that is too solid for moisture and air to get into to start the breakdown process.

Don't let the litter get wet

Do not let a deep litter bed get wet by rain blowing in doors or windows or from spillage around drinkers.

If it does get wet, move the drinkers and turn the litter over. Hang the drinkers higher to avoid spillage, or create a grill around the drinker with a drip tray beneath it. Remove wet areas and replace with fresh shavings.

Don't let cakes form

Remove any caked dry areas, or break up and stir in with the dry stuff.

Periodically empty any nest box litter onto the floor - once a week would be good, to keep the nests fresh. Top up any areas where litter is a bit thin or where you have removed wet or caked hard litter.

Do not overstock

If you keep your birds indoors all the time New Zealand's animal welfare regulations advise the maximum number of birds per square metre:

• Large heavy breeds should be housed at no more than five birds per square metre;
• Laying strains of birds like Shavers and Hylines can be up to seven birds per square metre;
• If the birds have a free range area outdoors all day their shed needs to be big enough to house 10-11 birds per square metre, to allow for wet days and for the 15 hours of darkness in winter when they will have to stay inside;
• Chicks and growing birds can be stocked at more birds per square metre than adult birds.

Tip - Don't use hay or straw in a deep litter bed

Straw is not suitable as a deep litter material, although it can be useful once the litter bacteria is working. Neither straw nor hay are absorbent in the stalky stage, and hay carries mould and fungi spores which can affect the birds' (and human!) lungs. Hay is not suitable for nests either, because of the risk of mould spores entering the pores of warm wet eggs and infecting the embryo.

8 tips for keeping your deep litter working

1. A scratch feed of grain sprinkled over the litter will encourage your birds to turn the shavings over, assisting in keeping litter dry and warm.
2. Birds won't dust bathe in litter if it is cold and damp, so make sure you stop leaks, spread out damp litter and remove or break up any "cakey" litter.
3. If you only put down a thin layer of shavings and clean it out twice a week you are not creating a true deep litter bed, which makes compost of the droppings which you can then use in your garden. The beauty of the deep litter system is it saves you the chore of a regular clean out.
4. Think of managing the litter as if it were a compost heap. The heat generated by a good aerobic deep litter will help kill off the "bad" bacteria - the ones that cause the horrible smell are usually the anaerobic bacterias which thrive when there is lack of oxygen.
5. Dry litter helps prevent coccidiosis (a parasitic disease caused by coccidian protozoa) developing into a full-blown infection as any "cocci" eggs that are shed cannot develop into massive infective populations in dry conditions.
6. The other side of coccidiosis control is you need to allow the birds to get a continual low dose so they build up immunity. If you clean out the litter all the time they never get a big enough dose to infect them so they get no immunity. Then, the one time you leave the litter for 8-10 days and it is shallow and warm and damp, your unprotected chickens can succumb to a cocci population explosion quickly. It's always a careful balance between enough cocci eggs for immunity, but not too much.
7. Other deep litter materials have been tried and mostly failed. Shredded newspaper was used for a time for broiler chicks, but it has its own problems that requires quite careful management, and it's no good for adult birds as it breaks down to dust very quickly. I think wool has been used too - well-scoured short stuff.
8. Pine post peelings may work for older birds but not for chicks. Shavings from timbers other than pine are OK but some can be very dusty and peppery. Shavings of wood like native totara will get right up your nose. Dry pine shavings are definitely the preferred way to go!