Overview
In the 1800s wool was a major export commodity for New Zealand. But this big money earner was threatened with scab, an infectious disease accidentally introduced from Australia.
Sheep scab was caused by the parasite Psoroptes ovis and was a significant animal health problem here from the 1840s to early 1890s. Signs of the disease were biting, scratching, or rubbing on the shoulders, back, or rump.
Wool came off in clumps, leaving bare patches of flesh that took on ‘a decidedly unhealthy green and watery appearance … If the disease be long neglected the sheep will present a miserable ragged appearance, and in some instances they will be all but naked.’(1) Left untreated, sheep could die from the disease.
The answer was to immerse the sheep in a hot solution of dipping powder like the one advertised in the metal sign shown here. Cooper’s Dipping Powder was an imported brand available to New Zealand farmers from the 1880s. The sign depicts a merino sheep, an important high country breed introduced to New Zealand in the 1800s. This logo was used on Cooper’s packaging too.
William Cooper, an English veterinary surgeon, developed the product after conducting experiments with arsenic and sulphur. Including arsenic was a source of pride for Cooper’s. It was stated in the advertising that ‘Non-poisonous dipping preparations have their uses, but for general purposes only the best results are obtained by arsenical powder, paste or dips.’(2)
Before potent dips were developed, sheep with scab were treated with less effective smears of tar, goose-grease, tobacco stalks, and brimstone or hot baths of tobacco, spirits of tar, and arsenic.
Care had to be taken when dipping. Cooper’s advised farmers that ‘Sheep should not be dipped when thirsty, over-heated, or full of food, or in the wet or very cold weather. Nor should they be excited or overdriven.’
The dipping of sheep couldn’t be hurried either. Long baths were suggested, as the chemicals needed plenty of time to penetrate the wool and reach the skin. Photographs depicting farmers dipping sheep in baths show them holding the animals in with long poles to make sure the chemicals soaked in. A good dip was not meant to discolour the wool, and it also controlled burrowing lice and ticks.
The government introduced legislation like the 1878 Sheep Act to protect the wool export industry. This ‘Act to provide for the Eradication of Scab in Sheep’ consolidated earlier attempts to control the disease. It meant that farmers could be fined for having scabby sheep in their flocks.
References
(1) ‘Scab in Sheep’, New Zealand Country Journal, vol. 1. 1877, pp88 89.
(2) Advertisement for Cooper’s Sheep Dips, F W Hilgendorf, Farmers’ Foes in New Zealand and How to Cope with Them, Auckland, 1924, inside front cover.
Further reading
• Hargreaves, Ray and Holland, Peter. 1997. ‘On the Sheep’s Back: The Heyday of Pastoralism’ (plate 43), in Malcolm McKinnon (ed), Bateman New Zealand Historical Atlas.
• Carter, Bill, and MacGibbon, John. 2003. Wool: A History of New Zealand’s Wool Industry. Wellington.
Text originally published in Tai Awatea, Te Papa's onfloor multimedia database (2006)