In lieu of an abstract, here is a brief excerpt of the content:

Chapter 12 Sheep Breeding in Colonial Canterbury (New Zealand) A Practical Response to the Challenges of Disease and Economic Change, 1850–1914 Robert Peden Sheep farming was the most important agricultural industry in New Zealand from the 1850s to late in the twentieth century. The industry was founded on fine-wooled Merinos imported from the Australian colonies, and wool was the most valuable single agricultural export until the late 1960s.1 However, the year 1882, when the first shipment of frozen mutton was made from New Zealand to Great Britain, marked a watershed. From that time, meat became increasingly important to New Zealand’s economy. The crossbreeding of sheep, and in particular the development of the Corriedale breed in colonial Canterbury, is often seen in the context of the establishment and expansion of the frozen-meat industry.2 The argument, put simply, is that, before the advent of refrigeration, farmers raised Merino sheep for their wool; after 1882, they raised crossbred sheep for their wool and their meat. However, experiments crossing British rams over the base Merino flock began almost from the outset of organized settlement and were a response initially to the disease of footrot. There were also economic conditions in the prerefrigeration era that encouraged sheep breeders to experiment with crossbreeding—in particular, the  | Robert Peden increasing demand for combing wool by English processors and the requirement for a larger-framed, meatier, and faster-maturing type of sheep than the Merino for the local butchers’ market and for boiling down. In fact, it was the very success of these experiments in crossbreeding that enabled Canterbury farmers to take advantage of the new market made available by the opening of the frozen-meat trade with Great Britain after 1882. In this chapter, I examine these issues and explore the dilemma that breeders faced in trying to develop a sheep breed that was suited to the local environment, one that would resist the challenges of footrot and at the same time satisfy the changed demands in the marketplace for wool and surplus sheep. I contend that footrot was a primary reason for the early experiments in crossbreeding. Footrot was the most serious sheep disease in the Canterbury region from the late 1860s, and it continues to be a major animalhealth concern for present-day farmers who raise fine-wooled sheep. A 2001 survey of New Zealand Merino farmers cited footrot as the second most significant disease after gastrointestinal parasitism.3 Footrot has significant economic costs for farmers. Sheep become lame and are less inclined to graze, with the result that they lose weight, grow less wool, have a lower lambing performance, and are more prone to fly strike, which, if not treated, will lead to their slow and painful deaths. Over and above the costs from the loss of production, the management of the disease is expensive in terms of the cost of treatment and the cost of labor. If the disease is such a problem for Merino farmers in the twenty-first century—when we know its etiology and have a sound understanding of its management and when farmers have access to vaccines and antibiotics —then pity the farmer in the nineteenth century who had none of this knowledge and only limited scientific and veterinary support. Etiology of Virulent Footrot To set a context for the problem of footrot in the colonial setting, we should firstlookattheetiologyof thedisease.Footrotiscausedbythecombinedeffect of two gram-negative anaerobic bacteria: Fusobacterium necrophorum and Dichelobacter nodosus.4 In warm, moist conditions, the skin between the claws of sheep can become softened and raw, allowing the hoof to be invaded by these bacteria. Epidermal penetration by F. necrophorum creates the condition of ovine interdigital dermatitis. The presence of D. nodosus at this stage results in virulent footrot.As the disease spreads in the hoof,it destroys infected tissue so that the horny part can become almost completely detached.Virulent footrot is highly contagious and can result in 100 percent morbidity.5 Sheep Breeding in Colonial Canterbury |  D. nodosus is able to survive for long periods within the hoof with no external signs that the hoof is infected, but it does not survive outside the host for more than two weeks.The transmission of infection is determined by environmental conditions, and moist conditions above ten degrees centigrade are a precondition for the development and spread of the disease. Increased stocking rates will increase the rate of disease spread.A long spell of dry conditions will result in a...

pdf

Additional Information

ISBN
9780821443101
Related ISBN
9780821418857
MARC Record
OCLC
681350866
Launched on MUSE
2012-01-01
Language
English
Open Access
No
Back To Top

This website uses cookies to ensure you get the best experience on our website. Without cookies your experience may not be seamless.