Obituary: James Campbell Percival discovered the toxin that causes facial eczema

by Neil Percival, M.Agr.Sc (Massey)                                                               

The late Cam Percival, a former Ruakura Animal Research Centre scientist, had three distinct sides to his life’s work:  Cam the scientist at Ruakura and Uruguay, Cam the specialist livestock advisor for the World Bank, and Cam the farmer.

Through all of those roles Cam made significant advances for agriculture in New Zealand and internationally.

After he returned from the Japan Occupation Force, he gained work at the Ruakura Animal Research Centre as one of its first scientists. 

His initial research was with the feeding regimes for early and late weaned calves. This was published in the annual Ruakura Farmers’ Conference and the NZ Society of Animal Production Proceedings.

Cam’s major contribution was the discovery that facial eczema (FE) was caused by a fungal toxin called sporidesmin.  This was the key to getting the momentum going for today’s sophisticated FE control systems.

Around 1956/57 he observed a “black cloud” of dust coming from the mowers used to harvest the grass for feeding trials. Samples of this “black cloud” were fed to guinea pigs which then showed FE symptoms.

This work was published in Nature, Proceedings of the NZ Society of Animal Production and The New Zealand Journal of Agricultural Research.

The initial work was undertaken with R H Thornton from the Soil Bureau of the DSIR.  It took about 20 years from the formation of the Ruakura Animal Research Centre to publication of this work, underscoring the immense importance of the finding.

After the discovery of the cause of FE, it wasn’t long before controls were appearing. These included spraying pasture with fungicide, feeding alternate forages, predicting risk periods based on grass minimum temperatures and rainfall data, dosing sheep and cattle with zinc to negate the effect of the toxin, and breeding sheep that can handle the toxin. 

By the time these controls were developed, Cam had moved on to new challenges, in Uruguay!

His success at Ruakura led to work with the Food and Agricultural Organisation , a branch of the United Nations, at the La Estanzula Research Centre in Uruguay. He did a lot of agronomic work there from 1965-1967, such as trialling different grasses and clovers.

Cam subsequently became a consultant to the World Bank as a loan appraisal officer for projects where livestock improvement was sought. He was involved in assessing about 20 projects between 1969–1981, mainly in Central and South America.

Some of those projects were hugely successful, such as funding widespread irrigation in Spain and setting up the research stations in Ireland, where Moorepark and Grange are as famous in their own right as Ruakura.

Finally, Cam the farmer. Cam’s father had been a farmer, in Ireland. Within two years of starting at Ruakura Cam leased the Pirongia race course with 700 ewes. Then in 1950 he bought 10ha of swampy land next to Ruakura and for a while milked 20 cows before and after work.

 He later owned 20ha in Te Rapa and 80ha of undeveloped scrub land at Mamaku, which he developed into pasture. 

His farming days ended when he joined FAO in 1965, but that practical experience probably influenced his perspective in subsequent roles.

Although Cam made a major contribution to agriculture in NZ with his pioneering work on FE, he was modest about this work. He was widely known as a good practical scientist.

Cam was predeceased by his wife Mavis and survived by their children Anne (Sydney) and Murray (Auckland).


Author: Bob Edlin

Editor of AgScience Magazine and Editor of the AgScience Blog

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