The latest National Statistics from the Defra (The Department for the Environment, Food and Rural Affairs) Pig and Poultry Farm Practices Surveys are the result of a one-off specialist survey to assess how pig and poultry farming practices are affected by current agricultural and environmental issues.

The data are used in the calculations for the ammonia emissions inventory, according to Defra, and focus on housing and the storage and use of poultry manure. For the purposes of the survey, farms were classified in one of two main categories: layers or broilers/turkeys.

Storage and Use of Manure

The survey revealed that most poultry manure is not stored on farms. For layers, 60 per cent of manure is either spread or exported within one week, while this is even higher at 72 per cent for broiler/turkey litter. One-quarter of manure in both categories of farm was stored in the open, i.e. with no concrete base.

Typical storage periods for both groups were six to seven months.

On the most common final use of the manure on both types of farm was spreading on farm land (55 per cent for layer farms and 44 per cent for broilers/turkeys), followed by transfer to another farm (36 and 26 per cent, respectively). Only two or three per cent of the manure was composted.

Application of Poultry Manure

Poultry manure was applied to fields across all the time periods given in the survey, i.e. August, September, October and November to July.

Typical application rates were seven tonnes per hectare for layer manure, and nine tonnes for litter-based manure. Where contractors were used to spread manure (45 per cent of farms in both categories), nearly all spreading was done by them.

No incorporation of the manure was practised by a minority of both types of farm (31 per cent for layer manure and 22 per cent for litter-based manure). Of those farms that did incorporate the manure, nearly all did so within one week of spreading, and most within 24 hours.

Broiler and Turkey Farms Surveyed

The average number of birds on the holdings surveyed with deep litter systems was just under 131,000 birds, while on free-range farms, the average was almost 9,900. The proportions of holdings with in-house drying of litter were 19 and 20 per cent, respectively.

For turkeys, there were an average of 11,800 birds on farms using deep litter systems, and 2,600 on free range. In-house litter drying was practised on 11 per cent of the deep-litter farms and none of the free-range farms.

The survey showed that the average growing cycle of a broiler is 48 days to slaughter, and that holdings with broilers have an average of seven production cycles per year with an average of 11 days between cycles. Turkeys are slaughtered at 145 days for the females and 134 days for the males. There are usually just two cycles per year with an average of 51 days between cycles.

Breeding Hens

The average number of breeding hens on each holding varied between different housing types: the averages were 21,600 for deep litter, 263 for free-range and 27,700 for barn/perchery houses.

Pullets and Laying Hens

The average number of laying hens on the holdings at the time of the survey also varied with housing type: deep pit cages, 105,000; belt or scraper cages, 65,000; free-range, 11,000 and barn/perchery, 24,000. The average numbers of pullets were 59,000, 36,000, 8,600 and 34,000, respectively.

For the free-range systems, the majority (56 per cent) of holdings provided grass and trees on the range, and 41 per cent had only grass.

Also for free-range systems, the average outdoor range was 14 hectares, with 1,720 square metres of house. The proportion of time birds spend out on the range averaged 52 per cent.

Half of the holdings used paddock rotation, with an average of six paddocks and 24 weeks between rotations.

Most of the paddocks (60 per cent) were re-seeded once in three years or less often. Seventeen per cent were re-seeded every year, and 24 per cent every one or two years.

Further Reading

-

You can view the full report by clicking here.

May 2010