Pigs:Too little early and too much late
By Simon Wragg
MOST pig producers over-feed protein in finisher rations, thereby jeopardising the UK competitive position.
MLC pig scientist Pinder Gill. says that trials at the commissions Stotfold pig unit which reduced the amount of dietary protein fed as pig liveweight increased cut feed costs by 80p a head for 90kg and £1.50 a head for 107kg finished pigs.
"As the pig gets older its protein requirement falls. A 30-50kg grower may need 0.83g/MJ DE lysine requirement – 21% protein – whereas a 70-90kg finisher requires 0.50g/MJ DE lysine – 16% protein.
"Too little protein is fed in the early stages and too much in the later stages. Ideally, the ration should be altered daily, but that is impractical."
To counter this a four-phase batch feeding system has been introduced to the ad lib dry feed system at the 270-sow unit. Liveweight gain has increased by about 20% to 980g a day for 30-90kg pigs (P2 10mm backfat), increasing the number finished.
"Protein requirement for boars and gilts up to 90kg is similar in ad lib systems without jeopardising meat tenderness, which goes against past research."
Over 90kg, boar feed conversion increases to 40% over that of sows, improving net margin a pig sold from £2.31 to £4.34. The margin for gilts falls from £1.28 to £0.83, suggesting taking sows to heavier weights is uneconomic.
"While there is an economic benefit of taking boars to a heavier weight, producers will have to carefully research the target market," he warns.
A wet feed system is better suited for batch feeding, according to Mr Gill, giving more opportunity to replace concentrates with cheap proteins, such as cereal and distillery by-products.
Although wet feeding can cut feed costs further, only 15% of UK units have adopted the system.
"The benefits of the batch system will be mainly seen when pigs are evenly matched by size and age. Individual pigs are not under or over fed so feed efficiency is maximised."
The batch system means overheads can be spread over more finished pigs.
Closer profiling of protein requirements reduces nitrogen excretion by 0.5kg a pig (0.2 finished pig places a hectare under NVZ rules), reducing the risk of pollution, he adds.
Matching rations more closely to protein requirements could save up to £1.50 a pig and reduce nitrogen excretion, says the MLCs Pinder Gill.
PHASE FEEDING POINTERS
• Improve growth rates with phase feeding.
• Evenly-sized growers do better.
• Reduce risk of nitrogen pollution.
• Look for market opportunities for heavier pigs.