Sheep and Goat Science Commons^™

Anthelmintic Resistance In Sheep Across Ireland And The Uk: A Literature Review Of The In Vivo Versus In Vitro Methods, Megan Tumulty

SURE Journal: Science Undergraduate Research Experience Journal

Background: The animal welfare and production consequences of gastrointestinal nematode infections, namely Nematodirus battus, on sheep are compelling. The control of gastrointestinal infections has been heavily reliant on the administration of anthelmintics since their introduction into mainstream use in 1960. However, their frequent and often excessive use has resulted in anthelmintic resistance being reported extensively in several gastrointestinal nematode species. The prevalence of anthelmintic resistance as well as the increase in the number of cases of multiple-drug resistance in nematode populations now poses substantial hindrance on the viability of sheep production systems. However, despite the threat N. battus poses …

Ai : Artificial Insemination Of Sheep, David Windsor

Journal of the Department of Agriculture, Western Australia, Series 4

Artificial insemination (Al) is used widely in the dairy and beef industries and often performed by farmers themselves. By contrast, sheep breeders generally require assistance from vets when frozen semen is to be used. However, recent experiments with frozen semen are indicating that do-it-yourself Al may soon become a reality.

Lupin Stubbles : Getting The Best With Weaner Sheep, Keith Croker, Colin Mcdonald, Jeremy Allen

Journal of the Department of Agriculture, Western Australia, Series 4

Sweet lupins are now grown on about a million hectares in Western Australia each year. If half of the State's seven million weaners were grazed as recommended on half of the lupin stubbles, it could generate about $15 million from reduced supplementary feeding, greater wool production and other advantages. But correct management is important, particularly knowing when to take weaners out. Research by the Department over the last five years is now indicating how this should be done.

Choosing Shower Dips For Sheep Lice, Tony Higgs, Bob Love

Journal of the Department of Agriculture, Western Australia, Series 4

The performance of all shower dip chemicals for sheep lice can vary depending on the active chemical and the conditions under which they are used.

Department of Agriculture trials have indicated that the wettable powders coumaphos and magnesium fluorosilicate were less effective at eradicating sheep lice than were synthetic pyrethroid and organophosphate dipping chemicals.

However, failure to eradicate sheep lice may be the result of several factors, many of them related to management.

Do Farmers Really Want To Eradicate Sheep Lice?, Chris Hawkins

Journal of the Department of Agriculture, Western Australia, Series 4

With the termination of Western Australia's Sheep Lice Eradication Campaign in 1993 farmers' views about the eradication of sheep lice are of greater relevance now than in the past. Lice control now rests with individual farmers and continuing local lice cell groups .

A recent survey of producers in the Moora Shire provides some key insights into farmers' thoughts about sheep lice and their eradication.

Progress Toward Eradication Of Virulent Footrot, Bob Mitchell

Journal of the Department of Agriculture, Western Australia, Series 4

Western Australia is well placed to eradicate virulent footrot from the State's sheep and goat populations.

Between 1950 and 1993 the proportion of sheep flocks with footrot fell from about 15 per cent to less than 2 percent, and the 1990-92 outbreak has been turned around. One hundred and eighty properties (]. 7 per cent) of flocks, mostly in the high rainfall South-West, are in quarantine for footrot today.

This high level of footrot control is the result of strong support from the sheep industry and years of good cooperation between farmers and the Department of Agriculture.

Western Australia leads …

Are Foxes Serious Predators Of Stock?, Peter Mawson, John Long

Journal of the Department of Agriculture, Western Australia, Series 4

Commercial farming of goats for mohair, cashmere and meat production is a rapidly developing industry in the south-west of Western Australia.

In this article, the authors discuss the results of two studies conducted by the Agriculture Protection Board in which the levels of predation of kids and lambs by foxes in commercial goat flocks, and an experimental multiple-birth genotype sheep flock in the southwest of Western Australia, were measured.

Understanding The Importance Of Eperythrozoon Ovis Infection In Sheep, Marc Kabay

Journal of the Department of Agriculture, Western Australia, Series 4

Assigning priorities for research on sheep diseases relies in part on understanding the prevalence and economic impact of each disease.

Eperythrozoon ovis infection in sheep, for example is a common, but not costly, disease.

Getting The Best Out Of Weaner Sheep In The Eastern Wheatbelt, Sally Revell

Journal of the Department of Agriculture, Western Australia, Series 4

A study of the growth of Merino weaner flocks over summer and autumn in Western Australia 's eastern wheatbelt during 1989 and 1990 has identified efficient weaner management strategies, and provided a basis for future research and extension needs of this area. The average liveweight of several weaner flocks was unexpectedly low at the start of summer. Weaner flocks may need to be supplemented before the start of summer to prevent undue weight loss at this time.

New Technique Joins The Fight Against Footrot, Laurie Depiazzi, Mike Palmer, David Pitman

Journal of the Department of Agriculture, Western Australia, Series 4

The diagnosis of footrot in sheep and goats is not an easy task. Two main techniques are used for diagnosis - inspection of diseased feet on a farm and laboratory testing of bacteria isolated from foot scrapings. The interpretation of the results obtained by these methods requires a good understanding of the various forms of footrot.

A new laboratory technique has halved the time taken to detect those strains of the bacterium, Bacteroides (Dichelobacter) nodosus, that cause each form of the disease.

Phomopsis-Resistant Lupin Stubbles As Feed For Weaner Sheep, Colin Mcdonald, Keith Croker, Jeremy Allen

Journal of the Department of Agriculture, Western Australia, Series 4

The breeding of sweet, narrow-leafed lupins with increased resistance to Phomopsis leptostromiformis, the fungus that causes lupinosis in sheep, is a breakthrough for the summer nutrition of weaner sheep. The new resistant varieties, Gungurru for the medium (325 to 450 mm) rainfall areas and Yorrel for low rainfall areas (less than 325 mm), were released by the Department of Agriculture in 1988.

This article discusses progress in a four-year project which is examining liveweight and wool production of weaners grazing Gungurru stubbles.

The Accumulation And Run-Down Of Dieldrin In Wethers Grazed On Paddocks Previously Treated With Dieldrin, Tony Albertsen, Roy Casey, Keith Croker

Journal of the Department of Agriculture, Western Australia, Series 4

In mid 1987, the organochlorines (O/Cs) DDT, dieldrin, heptachlor and chlordane were deregistered for agricultural and horticultural use in Australia. These chemicals had been used widely, and land on several hundred Western Australian farms, particularly where potatoes had been grown, was contaminated with chemical residues. Livestock grazing pastures on such land was also contaminated, and our beef exports were threatened. In 1988, the Western Australian Department of Agriculture started a two-year project to collect information from sheep which were grazed on land that had previously been treated with O/Cs, particularly dieldrin. The levels of O/Cs in body and wool fats …

Choosing A Calcium Supplement For Sheep Fed Cereal Grains, R L. Peet, Michael Hare

Journal of the Department of Agriculture, Western Australia, Series 4

Sheep fed cereal grains as an energy source over summer usually need added calcium because cereal grains are generally low in calcium (for example, 0.03 per cent calcium compared to 0.26 per cent phosphorus), and there may not be a natural source such as clover, weeds, leafy stubble or edible bush in the paddock.

The safestt and most effective calcium supplement is finely ground limestone added to the feed, but some farmers have used other sources of calcium such as gypsum and superphosphate in this manner.

Farmers' Estimations Of Sheep Weights To Calculate Drench Dose, R B. Besier, Diane Hopkins

Journal of the Department of Agriculture, Western Australia, Series 4

Undersosing with drenches is a mojor cause of anthelmintic (drench) resistance in worm parasites of sheep.

When farmers use a drench at less than the recommended dose rate, some worms may survive, and their ability to resist treatment with the chemical involved is passed to their offspring. Over a period of time, matings between worms with different degrees of resistance can produce individuals able to resist the drench at the recommended dose rate or even higher.

Farmers must use adequate dose rates so that worms do not have a chance to survive treatment.

Weighing Scales For Sheep Do Pay, W D. Roberts

Journal of the Department of Agriculture, Western Australia, Series 4

Sheep producers can improve production by using weighing scales and keeping accurate records of weights.

Withiut some objective measurement, such as weighing, producers have no accurate method of identifying the heaviest, lightest and average weight of a group of sheep.

They could try to esstimate weight by eye - but most people are poor judges of body weight.

Evaluation Of The Crack Approach For The Control Of Drench Resistance In Sheep Worms, J R. Edwards, Helen Chapman, Jon Dunsmore

Journal of the Department of Agriculture, Western Australia, Series 4

The Department of Agriculture launched the CRACK approach to worm control in September 1985 in response to finding that anthelmintic (drench) resistant worms were present on 68 per cent of a random selection of Western Australian sheep farms.

The high cost of internal parasites in terms of lost production and drench costs, together with the high prevalence of resistant worms of farms, confirmed that changes were needed to existing parasite control measures in sheep.l

Sheep Lice : Prospects For Eradication, F C. Wilkinson

Journal of the Department of Agriculture, Western Australia, Series 4

Sheep biting lice have been controlled over the past 86 years in Western australia by a combination of routine insecticidal treatment after shearing and action by the department of Agriculture officers under legislation.

In July 1987 the sheep industry and the State Government will implement a plan to eradicate lice from sheep flocks in the agricultural areas and eventually in the pastoral areas. To achieve this the co-operation of many sectors of the industry will be required. Assuming co-operation is forthcoming, it is possible that by 1996 wool from agricultural areas will be free of lice and insecticidal treatment form …

Reproductive Wastage In Sheep, R W. Kelly

Journal of the Department of Agriculture, Western Australia, Series 4

The average lambing performance of Western Australia's ewe flock fluctuates between 60 and 70 per cent. Although this level of performance and variation between years is important for the sheep industry, individual farmers are more concerned about performance of their own flocks.

Figure shows the range in lambing performances that exist between farms in this State in 1983-84. The seriously poor performance of many flocks is apparentm - 28 percent of farms had less than 60 per cent lambing. By contrast, 24 farms had performances better than 100 per cent. The reasons for the large differences between farms ( and …

Ovulation Rate Of Ewes : Role Of Energy And Protein, E Teleni, J. B. Rowe

Journal of the Department of Agriculture, Western Australia, Series 4

Western Australia's sheep farmers are familiar with the low ovulation rate of Merino ewes and how this limits the lambing performance of ewe flocks.

One way in which ovulation rate and therefore lambing percentage may be increased is to feed seed of sweet lupin (Lupinus augustifolius) to ewes at mating. However, Department of Agriculture research has found that these increases do not show up consistently, and that there is considerable variability between farms.

If improved nutrition is to be a useful way to increasing ovulation rate, the mechanism by which nutrition affects ovulation rate must first be understood. This article …

Pregnancy Diagnosis Using Ultrasound, M A C Johns

Journal of the Department of Agriculture, Western Australia, Series 4

Few Western Australian ewe flocks are diagnosed for pregnancy despite the precence of high numbers of barren ewes. Surveys of farm flocks in the early 1970s recorded that between 14 and 29 per cent of ewes failed to lamb each year.

Techniques for diagnosing pregnant ewes have been available for many years, but ultrasonic devices and computer technology have made it possible for skilled operators to determine whether ewes are pregnant and more importantly, whether they have one, two or more foetuses.

Once the number of pregnant ewes is known farmers can use labour more efficiently. They can minimise the …

More Lambs From Feed And Chemical Treatments, K P. Croker

Journal of the Department of Agriculture, Western Australia, Series 4

The ovulation rate, or the number of eggs shed per ovulating ewe, represents the upper limit of the capacity of a flock of ewes toproduce lambs. Several methods can be used to increase ovulation rates and lambing percentages of ewes, including selection for better breeding, feeding and the use of chemicals.

The potential for improving the reproductive performance of Western Australia's ewe flocks by the use of different approaches to breeding was discussed by L.G. Butler and R.P. Lewer in the Journal of Agriculture in 1983.

This article mainly discusses the research conducted by the Department of Agriculture's Sheep and …

A Survey Of Drench Resistance In Sheep Worms, J R. Edwards, R. Wroth, G. C. De Chaneet, R. B. Besier, J. Karlsson, P. W. Morcombe, D. Roberts, G. Dalton-Morgan

Journal of the Department of Agriculture, Western Australia, Series 4

Sheep worms which are resistant to chemical drenches have been detected with increasing freuency is Western Australia's south-western farming areas between 977 and 1980. These worms have anthelmintic resistance and such genetis resistance puts essential internal parasite control practices at risk.

This prompted veterinarians in the Esperance, Albany, Bunbury, Geraldton and Northam areas to survey farms to determine the prevalence of resistance to drenches and to define those sheep management practices which encourage its development.

This article describes the survey which was conducted to assess the extent of drench resistance, what causes its build-up and how it can be controlled …

'Dermo' Fleece Rot And Body Strike On Sheep, S G. Gherardi, S. S. Sutherland, N. Monzu

Journal of the Department of Agriculture, Western Australia, Series 4

Blowfly strike is one of the major problems confronting the sheep industry in Austrsalia, with an estimated totsalcost of control eceeding $100 million each year.

Sheep are susceptible to five types of strike: body, breach, poll, pizzle and wound. Body strike, is of greater economic importance because its sporadic occurence from year to year makes it difficult to predict and cintrol. Outbreaks of body strike after rain can affect large numbers of sheep and inflict severe production losses.

In eastern Australia fleece rot is generally considered to be the main predisposing factor to blowfly strike, but in Western Australia evidence …

Dispelling Some Myths About 'Dermo', J R. Edwards

Journal of the Department of Agriculture, Western Australia, Series 4

There are a lot of misconceptions and myths about dermatophilosis, a disease which can kill young lambs, affect wool quality, make shearing difficult and make sheep susceptible to fly strike.

One misconception is perpetuated by the incorrect use of the name mycotic dermatitis, which implies that a fungus causes the disease. This is not so.

The disease is caused by the bacteria Dermatophilus congolensis, which attacks the sheep's skin and eventually forms a lesion or scab in the wool, and so is better called dermatophilosis, 'dermo' or 'lumpy wool'.

Veterinary Epidemiologist at the Albany Regional Office, J.R. Edwards, discusses …

New Developments In Footrot Control, R B. Richards, L. J. Depiazzi, R. V. R. Gwynn

Journal of the Department of Agriculture, Western Australia, Series 4

The eradication policy for footrot in sheep adopted by the Western Australian Department of Agriculture has produced an overall decline in the number of properties with the disease.

Our knowledge of the disease has improved substantially as a result of the research conducted at the Slabany Regional Veterinary Laboratory in recent years. Laboratory tests now sssist stock inspectors and veterinary officers to distinguish between different forms of footrot and to quarantine and eradicate accordingly.

The recent discovery of more effective foot-bathing solutions by officers of the Victorian Department of Agriculture will greatly assist further eradication procedures.

Western Australia's sheep industry …

Protecting Off-Shears Sheep In Adverse Weather, T M. Ellis

Journal of the Department of Agriculture, Western Australia, Series 4

In January 2982 in the Narrogin-Darkan area of Western Australia, about 14,500 sheep up to 40 days off-shears died after a 48-hour period of heavy soaking rain that followed a thunderstorm three days previously. An estimated 100,000 sheep died throughout the South-West at the time.

P. G. Buckman - at the time Department of Agriculture District Veterinary Officer, Narrogin - surveyed 17 properties in the area. He found that losses in unshedded sheep 0 to 40 days off-shears ranged from 0 to 84 per cent of sheep on the property with an overall average of 27.9 per cent. Rainfall in …

Lupinosis : A Disease Still With Us, Jeremy G. Allen, P. Mcr. Wood, K. P. Crocker, J. Hamblin

Journal of the Department of Agriculture, Western Australia, Series 4

Current research on lupinosis continues to reveal what a complex problem it is, but the improved understanding should help to reduce losses.

Diagnosing Pregnancy In Sheep : The 'Scanopreg', R H. Wroth, M. J. Mccallum

Journal of the Department of Agriculture, Western Australia, Series 4

The "Scanopreg", an ultrasonic machine for diagnosing pregnancy in sheep, is effective as early as eight to nine weeks of pregnancy, and could therefore be a useful management tool.

Controlling Annual Ryegrass Toxicity, C H. Trotman

Journal of the Department of Agriculture, Western Australia, Series 4

Eight years of intensive work has changed annual ryegrass toxicity from an unknown killer to a manageable problem.

Some Basic Facts About Primary Blowflies, N Monzu

Journal of the Department of Agriculture, Western Australia, Series 4

Research has begun on blowfly species attacking sheep in Western Australia. Already this research has indicated the importance of a species in Western Australia which is not a problem in the Eastern States.

Future management of sheep flocks to minimise fly strike may require recognition of the differences between blowfly species. This article gives a description of the primary species - those which can initiate strikes.