New Project Hopes To Solve OPA Riddle

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1 Issue 24 Spring 2006 more from New Project Hopes To Solve OPA Riddle Scientists at Moredun are leading a new project to evaluate the potential for controlling OPA in the Scottish national sheep flock. The objective of the three year project will be to try and identify some of the risk factors involved in the transmission of JRSV, the virus which causes Ovine Pulmonary Adenocarcinoma (OPA or Jaagseikte) in sheep. OPA is an infectious lung cancer of sheep, caused by a retrovirus, JSRV. There is no treatment or preclinical diagnosis for OPA at this time and the disease is invariably fatal. OPA is a particular problem to the Scottish sheep industry with some farmers reporting the loss of 5-10% of sheep per year to this disease. Moredun has the largest research group looking at OPA and although our knowledge of this disease continues to increase, there are still lots of questions that remain unanswered. It is hoped that this project, which is being conducted in partnership with SAC and BioSS and funded by SEERAD, will help determine; how common JSRV infection is in Scotland how JSRV is transmitted in the field how long JSRV survives in the environment how common OPA is, how many flocks are infected and what proportion of animals are infected in an affected flock Farms throughout Scotland will be selected at random and asked if they wish to take part in this survey. Vets from local VI centres throughout Scotland will then visit 125 farms who have agreed to take part and collect blood samples from sheep selected at random by computer. These blood samples will then be screened by the new serodiagnostic test developed by Moredun to see if the sheep are infected with JSRV. Farmers will also be visited by a researcher from SAC who will help them complete a questionnaire about the flock history of OPA and to look for possible risk factors for JSRV infection or OPA disease on their individual farm. Results of both the test and the questionnaire will be anonymous. It is hoped that at the end of this study we will be in a much better position to assess the effectiveness of various control strategies for OPA and advise farmers and vets about how they can best deal with this disease at farm level. OPA leads to the production of excessive amounts of lung fluid, full of JSRV In this Issue Moredun supports new cattle health forms 2 Worm Control strategies - ACME 3 Zoonotic risks at lambing 4 Update on Chlamydial abortion 5 Summer show schedule 7

2 Editors Comments Best wishes to all our members and supporters for What Moredun has always had as a major priority is the translation of good research into good practical advice. A wonderful example of this is the feature on ACME, a four point plan to control worm infestations in sheep. By following the clear and logical steps detailed in this programme farmers can effect dramatic improvements in the control of parasites in their flocks. Please spare the time to digest this article and I am sure you will see the sense of the strategy. The article on chlamydial abortion in this issue of MFM is timely both in the sense that the lambing season is now upon us and Moredun is hosting an international conference on the subject later this year. The latter highlights the role that Moredun plays in international science and it is fitting that Pentlands Science Park will host this prestigious event. Safety is an ever present concern when we are engaged in our work and there is a timely warning in this issue to watch out if you are pregnant and may be involved with lambing. The New Year always brings the mouthwatering prospect of spring and summer agricultural shows and events. As always Moredun will be present with our displays and experts at the shows listed inside and keep an eye on our website for further details of events in your area. Professor Willie Donachie Deputy Director of Moredun and Editor Moredun and QMS partnership high-lights liver fluke problem Moredun has teamed up with Quality Meat Scotland to produce two free fact sheets on liver fluke. The fact sheets, one focusing on the disease in sheep and the other in cattle, are available direct from Quality Meat Scotland ( info@qmscotland.co.uk) or can be downloaded from Moredun Voted One Of Scotland s Healthiest Employers Moredun has been voted one of the top ten organisations in Scotland at promoting its workers health and wellbeing by the BBC Big Challenge Health Works Awards Golf, cricket, football, badminton and running are just some of the activities that Moredun staff can regularly take part in. On-site pilates classes and the chance to experience massage and reflexology have also proved popular. Moredun has also built deluxe shower rooms on-site for staff to use as well as a secure bike shed to encourage workers to cycle to and from its base at Pentlands Science Park, near Penicuik. This award, for best medium sized employer will supplement the Gold Standard that Moredun was awarded by the Scotland s Health and Work Initiative (SHAW) in December Professor Julie Fitzpatrick, Scientific Director and Chief Executive was delighted that Moredun had received this National award. She commented As a relative newcomer to Moredun, I was delighted to be involved in a group where the ethos was very much work-hard, playhard. We look forward to continuing to promote health in the workplace. New Look Cattle Health Declaration Forms Representatives from Moredun have helped to develop a new, industry wide cattle health declaration form to improve the consistency of information provided to buyers in Scotland. Until recently, many different formats have existed for cattle health declarations in Scotland, all trying to convey the same information. An all industry stakeholder group made up of breed societies, auction marts, vet bodies, producer groups and health scheme providers was therefore established by NFU Scotland to look at how the current forms could be improved. The new look form, which is both clearer and simpler, was launched at the Perth Bull Sales in February. Professor Willie Donachie and Dr Mark Dagleish from Moredun both sat on the stakeholder group and were delighted to be able to assist in the development of these improved forms. Nigel Miller from NFU Scotland shared their enthusiasm. It is a superb achievement that this group of stakeholders has managed to share expertise and achieve a common goal. As we near the resumption of beef exports, it could not have come at a more crucial time for the industry. 2

3 Helping To Keep Parasitic Worms At Bay Parasitologists from Moredun have developed a four point plan (ACME) to help farmers develop effective worm control strategies on their farms. The ACME message forms the central core of recommendations promoted by SCOPS (Sustainable Control of Parasites in Sheep) in a Defra initiative. A dopt a quarantine strategy C heck the efficacy of the anthelmintics M onitor flocks to decide when to treat E nsure that you follow best practice Adopt a quarantine strategy to minimise the risk of importing anthelmintic resistance. Drench new stock being brought onto the farm with a macrocyclic lactone (clear drench) and a drug from another anthelmintic class such as a levamisole (yellow drench). Administer the drenches sequentially NOT simultaneously never mix different drenches within their containers or in your drenching equipment. If possible hold the animals off pasture for hours post treatment to allow the anthelmintics to work and for worm eggs that were produced pre treatment to pass out, minimising the risk of pasture contamination. The animals should have access to feed and water whilst off pasture. Parasitic intestinal roundworms cost the sheep industry millions each year In lost production samples are a good indicator of the situation in the flock as a whole. Samples taken and submitted from animals at the time of dosing can give a clearer picture of drench effectiveness. Monitor flocks to decide when to treat and what parasites to treat against. Faecal egg count (FEC) monitoring provides valuable information relating to which parasites are present and the seasonal patterns of worm infection on your farm. This information can aid in the decision of which treatments may be needed and those which would be most suitable. Monitoring can potentially help reduce the amount of drench used over a grazing season, by providing a guide to the appropriate drenching times and minimising off-target usage. Caution should be observed particularly when Always follow best practice when drenching interpreting low FECs. Egg production may not always relate to worm burden and the extent of worm associated damage. Also at certain times of the year worm populations may consist largely of immature or arrested worms. Ensure that you follow best practice advice regarding the use of anthelmintics. 1. Dose at the manufacturers recommended rate, do not underestimate weights. 2. Ensure that anthelmintics are stored correctly and that all dosing equipment is checked regularly. 3. Deliver the anthelmintic over the back of the tongue and not into the mouth to ensure that drench is taken up by the sheep efficiently. Check the efficacy of the anthelmintics you are using, using a post drench efficacy test. The collection and examination of fresh faecal samples from at least10 animals following treatment for worms can quickly indicate anthelmintic efficacy. The time after treatment depends on the drug being tested: 7 days levamisoles (II); days benzimidazoles (I) & days for avermectins (III). Mob (bulk) 3

4 Moredun hosts International Conference on Chlamydia Moredun is delighted to host the 4 th Annual Workshop of COST Action 855 between 3-5 September The conference, which will attract scientists from across the world, will focus on animal chamydioses, how they can be diagnosed and the development of effective vaccines. Chlamydia is a zoonotic agent, i.e. it can infect both animals and humans, so this two day event will also look at the zoonotic threat of this group of bacteria and how they can be minimised. Advice to pregnant women during the lambing season As many farmers start to prepare for the lambing period, Moredun would like to highlight the following Defra recommendations and strongly advise pregnant women to avoid helping out at lambing time. Pregnant women who come into close contact with sheep during lambing may risk their own health and that of their unborn child, from infections that can occur in some ewes. These include chlamydiosis (enzootic abortion of ewes - EAE), toxoplasmosis, Q Fever and listeriosis, which are common causes of abortion in ewes. To avoid the possible risk of infection, pregnant women are advised that they should: not help to lamb or milk ewes; avoid contact with aborted or new-born lambs or with the afterbirth; For further information please contact Dr David Longbottom, Chairman of the organising committee at Moredun on or log onto the conference website avoid handling clothing, boots etc which have come into contact with ewes or lambs. Although the number of reports of these infections and human miscarriages resulting from contact with sheep is extremely small, it is important that pregnant women are aware of the potential risks. In the unlikely event that pregnant women experience fever, influenza-like symptoms or persistent headache following contact with potentially contaminated material, medical advice should be sought. If a ewe aborts, farmers are advised to consult their veterinary surgeon and arrange for samples to be examined at their local VI centre to determine the cause. In the interests of hygiene, farmers should dispose of all afterbirths promptly and safely in accordance with relevant legislation. Thank You As a registered charity Moredun is indebted to donations from its members and supporters which help ensure that vital areas of our work can continue. However, special thanks must go to the following organisations, all of whom have made donations to Moredun in the last twelve months. Their support is greatly appreciated by us all. Border Union Agricultural Society Buckland Charitable Trust Bute Agricultural Society Caithness Agricultural Society Hybu Cig Cymru (Meat Promotion Wales) Janssen Animal Health J & JR Wilson Trust Langford Sheep Discussion Group Novartis Animal Health Pennine Sheepkeepers Association Perth Ram Society Pfizer Animal Health Romsey Agricultural & Horse Show Society Schering Plough Animal Health Volac International Limited William Angus Anderson (the estate of) Thank You Many thanks to everyone who ordered Christmas cards and gifts from Moredun in Nearly 4,000 was raised through the sale of cards and seasonal gifts which is a tremendous amount. Remember that we have a large range of books, videos and gifts available all year round and they can be ordered direct through our payment secure website Moredun PhD student numbers increase Neil Sargison bringing Moredun s PhD total to 15 4 Moredun has always been actively involved in education and training, not just for its staff but for undergraduates, postgraduates and visiting workers. The research institute has always attracted PhD students and the latest to join Moredun is Neil Sargison from the Royal (Dick) School of Veterinary Studies. Neil Sargison is one of the three vets currently undertaking a PhD based at Moredun, through the Veterinary Training Research Initiative (VTRI) and brings the total number of PhD students currently at Moredun to fifteen. His PhD, which will last 3 years, will focus on looking for markers for ivermectin resistance in Haemonchus contortus, a blood sucking parasite of sheep and goats. Although Neil will be based largely at Moredun, he will have supervisors at Moredun and Glasgow and Edinburgh Vet Schools. Neil is interested in all aspects of sheep health and production and was delighted to be given the opportunity to study at Moredun.

5 Protecting your flock against Chlamydial Abortion Chlamydial abortion is the most commonly diagnosed cause of infectious abortion in sheep in the UK and was responsible for 46% of cases submitted to veterinary investigation centres between 1995 and The disease is caused by a highly specialised bacterium called Chlamydophila abortus which is part of a family of bacteria known as Chlamydiaceae. Infection in sheep During pregnancy, C. abortus spreads to the womb of infected sheep where it causes inflammation in the placenta (afterbirth). This may lead to death of one or more of the lambs or to the birth of weak lambs. Sheep pick up infection via contact with infected ewes and their lambs at lambing time. Discharges, dead lambs and placentas from aborting ewes are heavily contaminated with the bacterium. If ewes are in early pregnancy when exposed to infection then they may abort that year, however, if they are in late pregnancy then infection may remain dormant (silent) until the next pregnancy when abortion may then occur. Ewe lambs may also become infected and abort in their first pregnancy. Ewes which have aborted due to C. abortus develop immunity and will not usually abort again due to this cause. Disease Chlamydial abortions typically occur in the last few weeks of pregnancy. Work at Moredun has shown that regardless of when sheep become infected, the organism does not cause disease until after 90 days of pregnancy. It multiplies in cells of the placenta instigating an intense inflammatory response the diseased placenta is usually dark red, thickened and will often have dirty yellow material sticking to the membrane between the button-like cotyledons. The typical manifestation of chlamydial abortion is the appearance of stillborn lambs accompanied by inflamed placentas one to two weeks before the expected start of lambing. However, a chlamydial infection can also produce full-term stillborn or weak lambs and it is not uncommon for an infected ewe to have one dead lamb along with one or more Sheep pick up infection through contact with infected ewes and their lambs at lambing time. live, weak or healthy lambs. Ewes commonly seem healthy following abortion although they may have a dirty vulval discharge for several days afterwards and some may occasionally go on to become sick due to inflammation in the womb. Diagnosis The key to diagnosing Chlamydophila infection is to submit aborted lambs with their placentas to the local veterinary laboratory for investigation. Your own veterinary surgeon may also advise submitting blood samples from aborting ewes. Control of Chlamydial Abortion The selection of a suitable control strategy for chlamydial abortion depends on the infection status of the flock. Veterinary advice should be sought regarding the best approach for your situation. PREVENTING SPREAD OF DISEASE During an outbreak of disease, abortion material and contaminated bedding should be disposed of effectively (e.g. by burning) and aborted ewes should ideally be isolated from the rest of the flock for 6 weeks. These measures should help prevent the spread of infection to other animals within the flock. In flocks which are free of infection, replacements should be purchased from EAE accredited flocks. There are two schemes in the UK that confer EAE accreditation: The Premium Health Scheme (EAE) run by the Scottish Agricultural Colleges Veterinary Services (Telephone ) and the Highlands and Islands Sheep Health Scheme (Tel: ). VACCINATION There are three vaccines commercially available to control chlamydial abortion; Mydiavac (Novartis Animal Health), Enzovax, (Intervet UK) and CEVAC Chlamydophila (CEVA Animal Health Ltd). Your veterinary surgeon will be able to advise you as to which product would be most suitable for use on your farm. The use of a vaccination programme is an effective way of reducing the incidence of disease in a flock over several years by rendering animals immune to infection. TREATMENT During an outbreak of abortion due to Chlamydophila then treatment with long-acting oxytetracycline (20 mg per kg body weight) will reduce the severity of infection. For best effect it should be given at 95 to 105 days of pregnancy. A second injection two weeks later will further reduce losses. However, some ewes will still abort and infection may still spread to other animals in the flock resulting in future disease problems. 5

6 VETAID responds to drought in Tanzania government, local partners, VETAID and community members) visited the area to assess the impact. The drought has negatively affected Community Animal Health Workers activities in 2 ways: Animals have moved in search of water, making the distances to be covered to give treatments often unmanageable. There is currently a severe drought in the Horn of Africa, causing serious food shortages and Simanjiro District in Tanzania has been badly hit by the crisis. Livestock are dying in large numbers since access to forage is extremely limited. Cattle are taken long distances for food and water. Many are too weak to make this journey; some are even unable to support the weight of water in their bellies after drinking and die as a result. This picture, taken by our project co-ordinator, shows the devastation to livestock. Food insecurity is reaching a critical point. The last government food aid assessment was carried out in June 2005 and the conclusion was that 14,000 people from 16 villages needed aid. There has been no rain since and now all 49 villages in the district have requested food aid, including the initial 16 villages. In January 2006 a monitoring team (comprising representatives from CAHWs are not always able to spare enough time to visit cases or attend training as they need to ensure their own animals are able to access water (this can involve waiting at a water point for an entire day). Community animal health treatments and training are continuing, but project progress in this area is slow. We are continually monitoring the project so that we can adjust to meet the ever changing needs of these communities. If you would like to support this, or any of our other projects, please contact the VETAID office at VETAID, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ. Telephone Animal Health Meetings Galore! held its first animal health Roadshow in November Over the years the Roadshow has grown in size and reputation and Moredun has since held a number of Roadshow meetings and joint events with other organisations to ensure that the problems that are highlighted as a concern in different areas of the UK are addressed. The 2005 Roadshow was another huge hit and attracted huge audiences all over the UK. Subjects covered included lameness, abortion, CLA, worm control, liver fluke, coccidiosis, mastitis, joint ill, OPA and cattle abortion. In fact the Roadshow was so successful; some events have spilled over into other months. For example a Moredun meeting was held in Lampeter in January on mastitis and joint ill and two further sheep health meetings have been held in Northern Ireland in February. will be mailed invitations to events in their area, but keep an eye on the Moredun website for information on any other meetings or events that might be being held; Another full house at the Exeter Roadshow meeting in November Frank Malone from Vet Science Division NI (left) and Frank Jackson from Moredun (right) enjoy the craic after the Ballycastle meeting in February Moredun now regularly holds events and evening meetings throughout the year in addition to the main November Roadshow. Members and supporters 6

7 Two new members for Foundation board Alistair Swanson and Tim Bebbington, new Moredun directors Tim Bebbington and Alistair Swanson were both appointed new board members at the AGM in September. Tim works as a vet in farm practice in Cornwall and Alistair is a sheep and beef farmer from Caithness. Both Tim and Alistair have been elected onto the board to represent the views of the farmers and the six regional advisors in their area; Tim for the South of England region and Alistair for the North of Scotland. They join the three existing regional chairmen, Roy Weir (Scotland South), Chris Lewis (Wales) and Judith Charnley (North of England). Summer Show Schedule Moredun in committed to supporting the farming community and attend the main agricultural shows and specialist sheep events throughout the UK. We will have stands or marquees at the following events throughout the summer, so if you plan to attend any of the events below, please come and say hello! Scot Sheep Wednesday 7 June Huntley, Aberdeenshire Royal Highland Show Thursday 22 Sunday 25 June Edinburgh Royal Welsh Show Monday 24 Thursday 27 July Builth Wells National Sheep Event 2006 Wednesday 2 August Malvern Chairman praises dedication of directors Moredun advisor awarded OBE! Warm congratulations to Lesley Stubbings who was awarded an OBE in the New Years honours list for her services to the sheep industry. Lesley Stubbings, who is an independent sheep consultant from Northamptonshire has been a Moredun advisor, regional chairman and board member for many years and her knowledge, experience and enthusiasm has always been greatly appreciated by everyone at Moredun. Lesley Stubbings OBE Past Director and Chairman honoured Two of Moredun s leading figures were awarded Honorary Fellowships of the Moredun Foundation at its AGM in September, in recognition of the outstanding contribution they have both made to Moredun. Professor Quintin McKellar was the Scientific Director and Chief Executive of Moredun between 1997 and 2004 and Professor Sir James Armour was the Chairman of the Moredun Foundation for four years, retiring in Foundation Chairman with retiring Moredun directors (pictured from left Donald Biggar, John Ross, Lesley Stubbings and Robbie Lennox) Three long standing Moredun directors were praised for their commitment as they stepped down from the board at the last Foundation AGM. Donald Biggar, a farmer from Castle Douglas, Robbie Lennox, a farmer from Argyll and Lesley Stubbings, a sheep advisor from Northamptonshire had served over 30 years on the Moredun boards between them, which is quite an achievement! John Ross, Moredun s Chairman, was full of praise for their dedication and thanked them for the long standing support they had given Moredun. Each was presented with a retrial gift, a personally engraved crook for both Donald Robbie and a stunning hand carved wooden bowl for Lesley. John Ross (centre) pictured with Honorary Fellows of the Moredun Foundation, Professor Sir James Armour (left) and Professor Quintin McKellar (right) 7

8 Moredun Foundation Newsheet Book - VOLUME 3 Now Available The Foundation has launched the latest volume of newsheets to be produced in book form. This third compendium of Moredun news sheets contains twenty of our most recent popular articles sent to Moredun Foundation members each quarter as part of their membership package. The topics are a mix of novel articles or an update on earlier publications relating to the diseases which afflict our flocks and herds. Titles include CLA, lameness, sheep scab, worm control strategies, liver fluke and orf. Volume 3 is available to members for just (plus 1.00 postage and packing). Please send orders to: Margaret Bennett Pentlands Science Park Bush Loan Penicuik EH26 0PZ Tel: Fax: margaret.bennett@moredun.org.uk News Sheets 1-20 Volume 3 Moredun Foundation Newsheet Books - VOLUMES 1 & 2 Now Available News Sheets 1-30 Volume 1 News Sheets 1-30 Volume 1 Earlier newsheets produced by the Moredun Foundation are also available as paperback books. Subjects covered in Volume 1 include Jaagsiekte, Watery Mouth, Detection and Treatment of Hypothermia, Border Disease, Footrot and lots more. Volume 2, launched in October 1999, contains newsheets on subjects like Maedi Visna, Pasteurellosis, Scrapie, Effective Ectoparasite Control and Ovine Abortion. Each volume is available to members for just (plus 1.00 postage and packing). Please send orders to: Margaret Bennett Pentlands Science Park Bush Loan Penicuik EH26 0PZ Tel: Fax: margaret.bennett@moredun. org.uk