13 March 1998

Phase feeding boosts

Phase feeding boosts

pig profits

Improved phase-feeding at FWs Easton Lodge could cut

feed costs by more than £10,000. Unit manager

Jasper Renold talks to a pig scientist to find out whats

involved. Simon Wragg reports

CHECKING the specification of pig diets against growth rates can highlight areas where nutrition can be improved, even for producers who have moved towards the principle of phase-feeding.

Thats the finding of MLC pig scientist, Pinder Gill, after a visit to FWs Easton Lodge pig unit. He found that lysine levels were not being reduced in line with body requirements as pig weight increased, despite three different diets being fed between 43-99kg liveweight.

"You may believe youre feeding three diets, but protein to digestible energy ratios are similar. In effect youre feeding one diet all the way through," Dr Gill told Easton Lodge pig unit manager Jasper Renold.

Research at MLC Stotfold (see panel) suggests a 30kg pig requires about 0.9g lysine/MJ DE when phase feeding. At 90kg this requirement falls to about lysine:DE 0.6g/MJ.

At Easton Lodge, Dr Gill calculates that under the present feeding regime, and especially at higher pig weights, lysine is over-fed putting a brake on growth rates (see Table 1).

Pigs at 73kg are over fed lysine:DE – currently 0.86g/MJ compared with a recommended 0.64g/MJ. Energy is being used for deaminating excess lysine in the form of dietary protein rather than increasing growth.

However, optimum level of lysine depends on many factors including age, weight, genotype, health status and production system.

Mr Renold is wary of cutting lysine levels too far, especially during the finishing period. "Im concerned that growth rates will reduce, especially for smaller pigs with a low appetite."

However, Dr Gill suggests reducing lysine:DE ratios in the Easton Lodge rations (see Table 2) would improve growth rates and save £5/t on the diet currently fed between 43-73kg, and £14/t for the diet fed between 73-100kg.

Easton Lodge figures suggest these estimated lower diet costs would save 38p a pig and £1.01 a pig in feed costs for the two groups respectively. Over the annual output of 7700 finished pigs, total savings amount to £10,700.

"We cannot afford to overlook savings of that size, but Im still a little unsure it can be achieved," comments Mr Renold.

However, research at MLC Stotfold on reducing 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.

In a commercial environment producers have a tendency to increase lysine levels to compensate for health status, appetite and digestibility of lysine in finisher rations, says Mr Renold.

But, to test what improvement can be achieved in a commercial environment, Easton Lodge is introducing a new trial diet specification for pigs from 73kg to finishing.

Lysine % has been reduced to 0.95, rather than lower MLC recommendation of 0.88% lysine, to allow for differences in health status, says Mr Renold. Feed saving will be nearer £10/t.

Trial groups of 160 pigs from the 73kg to finishing stage will be split equally – one half receiving the existing diet and the remainder receiving the new lower lysine specification, closer to MLC recommendations.

After three batches of finished pigs we will have an indication of how stock are performing on the new diet, suggests Dr Gill. However, FW will report on trial progress.

"The danger of on-farm trials is that theyre not controlled as rigorously as research trials. You might not, therefore, see the results you want when comparing figures with the Stotfold work," he adds.

The refined phase feeding trial began at at Easton Lodge last week. &#42

Is the present feeding regime at Easton Lodge, where lysine is being overfed, especially at higher pig weights, putting a brake on growth rates?

Table 2: Recommended change to diet specification for    pigs between 43-73kg and 73-100kg


Current Recommended

Pigs between 43-73kg

DE (MJ/kg) 14.00 14.00

Lysine (%) 1.20 1.05

Lysine:DE ratio 0.86 0.75

Cost saving (£/t) – 5

Pigs between 73-100kg

DE (MJ/kg) 14.00 13.75

Lysine (%) 1.20 0.88

Lysine:DE ratio 0.86 0.64

Cost saving (£/t) – 14

Summary of MLC Stotfold phase feeding research

Reducing dietary protein fed from 0.9g/MJ DE to 0.6g/MJ DE between 30-90kg liveweight improved pig liveweight gain by about 20% to 980g a day. It also saved feed costs of 80p/head for 90kg and £1.50/head for 107kg finished pigs.

Table 1: Growth rate comparison (g/day)


E.Lodge Stotfold opitmum

Gain Ly:DE Gain Ly:DE

30 to 50kg 783 0.97 750 0.87

50 to 70kg 868 0.86 800 0.72

70 to 90kg 861 0.86 850 0.67

90 to 110kg 797 0.84 900 0.62

Reducing lysine levels for heavier pigs could save over £10,000 in feed costs says Pinder Gill (right). Unit manager Jasper Renold is unsure if it can be achieved.