Sun-reactive paint for arks keeps pigs cool

29 September 2000

Sun-reactive paint for arks keeps pigs cool

This years Alastair Mews

Award, run by Freedom Food,

proved to be a close run

affair, with four candidates

vying for top prize.

Emma Penny reports on

their welfare ideas

SOMETIMES the simplest ideas really are the best – and thats what has won Norfolk-based LSB Pigs this years Alastair Mews Award, as well as winning the individual farmer category.

Set up in memory of Mr Mews, who was the inspiration behind Freedom Food, the award recognises individuals and companies who have made an outstanding contribution to animal welfare.

The entry from LSB Pigs does just that – and has resulted in the companys outdoor pigs enjoying much reduced temperatures in arks on hot, sunny days. This has cut heat stress on all pigs – including boars, reduced piglet and sow mortality – and has led to fewer cases of sunburn and sunstroke.

Behind these achievements is a simple initial idea which has been developed by the herds owner Robert Battersby and its manager Robert McGregor, who look after the 850-sow unit near East Rudham, producing 28-day-old weaners.

The pair were concerned about heat stress during hot, sunny days and the effect it was having on herd performance. On some days, temperatures inside arks could hit 40deg or more, resulting in heat exhaustion during farrowing, higher piglet and sow mortality, reduced boar fertility and heat stress on boars. Sunstroke and sunburn were additional concerns as pigs chose to remain outside rather than returning to hot arks.

A solution was suggested by a South African fieldsman, who pointed out that to keep anything cool in hot climates they usually painted it white.

The idea was adopted by LSB Pigs, who began experimenting with different paints. Emulsion and cellulose car paints were tried initially, before settling on a paint developed for the horticultural industry for use inside glasshouses and polythene tunnels. This paint has the advantage that it is sun-reactive, turning white under sunny conditions, but returning to a galvanised metal colour under cloudy conditions, which means arks can absorb some heat during cooler weather.

Painting arks has reduced the average temperature from 40deg on a very sunny day to 32deg, and initial trials on farrowing huts were so successful that all sow accommodation is now painted, including service arks.

Applied within minutes using a knapsack sprayer, the paint has a life of about two years and costs only £1.50/farrowing hut.

"Its a cheap measure that makes a dramatic difference to the pigs quality of life, and turns an oven into a shed," says Mr McGregor. "Its satisfying to view the herd at a distance. When the sun shines and the arks turn white I know the paint is doing its job."

He adds that since painting farrowing arks, sows return more quickly after feeding, rather than spending time in the wallow, which has benefited piglets. Growth rates have increased as a result, with piglet weights at four weeks old increasing from an average of 7.5kg three years ago to 7.9kg now.

Ark temperatures –

Painted v Unpainted


temperature (deg) 35 33 29 24

No paint

applied (deg) 41 35 30 25

Paint applied (deg) 33 30 24 23

Greenhouse paint is proving a success at LSB Pigs, says unit manager Robert MacGregor.

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