Livestock CRYPTOSPORIDIUM INFECTION IN CATTLE. Inside this issue: WINTER EDITION 2010 WORKING TOGETHER FOR A HEALTHIER FUTURE.

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1 WINTER EDITION 2010 Livestock WORKING TOGETHER FOR A HEALTHIER FUTURE Inside this issue: MATTERS BOVINE ABORTION We investigate the many causes of bovine abortion and look at preventative measures and treatment options available to farmers. CRYPTOSPORIDIUM INFECTION IN CATTLE We look at the key issues of Cryptosporidium, the life cycle of this infection and most importantly how we can prevent Cryptosporidium affecting our herds. Ireland

2 EXCELLENCE IN PRACTICE XLVets - We Excel The members of XLVets have worked hard to create what they see as a model of how practices can work together, sharing the latest ideas and passing on savings and joint expertise to clients. The group comprises of a number of the foremost farm practices in Ireland. With many years of combined experience, it is able to give expert advice on all areas of farm livestock, health and production. Ireland Invest in Health Don t pay for Disease XLVets member practices are dedicated to providing a high quality, cost effective service to their clients, to support long-term growth and future prosperity within the Irish livestock industry. Adare Veterinary Surgery Adare, Co.Limerick Telephone: Donal Lynch Veterinary Tullamore, Co.Offaly Telephone: Killenaule Vets Thurles, Co.Tipperary Telephone: Ormonde Veterinary Kilkenny, Co.Kilkenny Telephone: All Creatures Veterinary Clinic Roscommon Town, Co.Roscommon Telephone: Glen Veterinary Clinics Tipperary Town, Co.Tipperary Telephone: Mulcair Veterinary Clinics Cappamore, Co.Limerick Telephone: Riverview Veterinary Group Bandon, Co.Cork Telephone: Avondale Veterinary Clinics Arklow, Co.Wicklow Telephone: Glenbower Veterinary Group Killeagh, Co.Cork Telephone: O Connor Julian Vets Cashel, Co.Tipperary Telephone: Sliabh Luachra Veterinary Centre Rathmore, Co.Kerry Telephone: November 2010 Clerkin Vets Cootehill, Co.Cavan Telephone: Comeragh Veterinary Kilmacthomas, Co.Waterford Telephone: Gortlandroe Veterinary Clinic Nenagh, Co.Tipperary Telephone: Old Church Veterinary Hospital Ballyshannon, Co.Donegal Telephone: The future of agriculture needs a healthy industry, which needs healthy animals. XLVets is committed to being a part of this healthy future. Southview Veterinary Hospital Clonmel, Co.Tipperary Telephone: The Veterinary Hospital Gorey, Co.Wexford Telephone:

3 WINTER EDITION XLVets is a novel and exciting initiative conceived from within the veterinary profession. We are all independently owned, progressive veterinary practices located throughout Ireland committed to working together for the benefit of our clients. XLVets Ireland Member Practices Adare Veterinary Surgery Station Road, Adare, Co.Limerick All Creatures Veterinary Clinic Lanesboro Street, Roscommon Town, Co.Roscommon Avondale Veterinary Clinics Ferrybank, Arklow, Co.Wicklow Clerkin Vets 90 Bridge Street, Cootehill, Co.Cavan Comeragh Veterinary Main Street, Kilmacthomas, Co.Waterford Donal Lynch Veterinary Killurin Cross, Killeagh, Tullamore Co.Offaly Glen Veterinary Clinics Blind Street, Tipperary Town, Co.Tipperary Glenbower Veterinary Group Clashdermot East, Killeagh, Co.Cork Gortlandroe Veterinary Clinic 6 Church Street, Nenagh, Co.Tipperary Killenaule Vets Killenaule, Thurles, Co.Tipperary Mulcair Veterinary Clinics Dromsally, Cappamore, Co.Limerick O Connor Julian Vets 67 Main Street, Cashel, Co.Tipperary Old Church Veterinary Hospital The Mall, Ballyshannon, Co.Donegal Ormonde Veterinary 14 Barrack Street, Kilkenny, Co.Kilkenny Riverview Veterinary Group Distillery Road, Bandon, Co.Cork Sliabh Luachra Veterinary Centre West End, Rathmore, Co.Kerry Southview Veterinary Hospital Irishtown, Clonmel, Co.Tipperary The Veterinary Hospital Arklow Road, Gorey, Co.Wexford CONTENTS DAIRY HEALTH 07 Cryptosporidium infection: Sean Coffey, Mulcair Veterinary Clinic, looks at the detection of Cryptosporidium, its life cycle and advice on its prevention. REPORTS 03 Bovine abortion: Paschal Gibbons, Ormonde Veterinary, reports on the many causes of abortion, as well as providing advice on the prevention programmes available. 09 Neospora in cattle: Donal Murphy, Sliabh Luachra Veterinary Centre, reports on why Neosporosis has emerged as an important reproductive disease in cattle throughout the world and how it is now one of the most commonly diagnosed causes of abortion in Ireland. CONTENTS DAIRY AND BEEF 05 Johne s disease Vet Donal Lynch, Donal Lynch Veterinary, investigates this chronic debilitating disease that affects both dairy and beef breeds of cattle. XLVet Ireland Ltd Registered Office at: Dromsally Cappamore County Limerick Tel: XLVet Ireland No part of this publication may be reproduced without prior permission of the publisher. Disclaimer: XLVets does not necessarily share the views of contributors. No responsibility can be accepted for opinions expressed by contributors, or claims made by advertisers within this publication.

4 BOVINE ABORTION PASCHAL GIBBONS MVB MRCVS There are many causes of bovine abortion which can result in a serious economic impact on our farms. BOVINE ABORTION Bovine abortion is a serious economic loss to both dairy and suckler farms. Each abortion is estimated to cost around 710. Financial losses include the value of the calf, infertility and the forced culling of cows. CAUSES Veterinary Surgeon Paschal Gibbons XLVets Practice Ormonde Veterinary, Co.Kilkenny There are many causes of abortion, including genetic/developmental defects, raised temperature from any cause, trauma, certain drugs and infectious causes. A low level of abortion (1% to 3%) may be considered normal. Abortion storms, resulting in 20% to 30% of a herd aborting over a two or three week period can occur from brucellosis, Neosporosis or Salmonellosis. Salmonellosis is caused mainly by S.dublin and occasionally by S. typhimurium. The source of S. dublin is usually a carrier bovine animal, while S. typhimurium may be spread by rats, mice or wild birds. Salmonella abortion frequently occurs on its own, but occasionally adult animals may have fever and severe diarrhoea, often with blood, and calves can have diarrhoea. Abortions often peak at seven or eight months' gestation and the aborted foetus may be very decomposed, smelly and gassy. Abortions due to Salmonella peak between October and December. Leptospirosis is caused by Leptospira hardjo, which lives in the kidneys of carrier animals and is shed in urine. The spread of infection is facilitated by wet weather. In addition to abortion, Leptospirosis can cause milk drop syndrome (flabby udder with severe drop in milk production and spontaneous recovery in two or three weeks), infertility and the birth of weak calves. Leptospirosis is quite difficult to detect in foetuses. Neosporosis is caused by Neospora caninum. Abortions occur at any stage, but peak at four or five months' gestation. Many of these foetuses are never found. Dogs and foxes are the source of the infection. Neospora abortion often results in mummified (dried out) foetuses. If an infected animal produces a full-term live calf, then the calf is likely to be infected too. Therefore, if Neosporosis is diagnosed in a particular animal, its dam and its progeny could well be infected. Once infected with Neospora, animals are infected for life. Infected animals will be two to six times more likely to abort than Neospora-negative animals in the same herd. The agent is transiently shed (for up to three weeks). Even if the current farm dog was the source of the infection, by the time abortions commence, the dog has probably stopped shedding, so the farm dog should not be put down or got rid of once an outbreak occurs, as it poses no further danger. Dogs should be removed from calving areas and should not be allowed access to foetuses and placentas. BVD (Bovine Viral Diarrhoea) is known to cause a wide variety of conditions, including infertility, early or late abortions, and congenital defects. The source of infection is an animal shedding the virus. Such animals can shed either continually - called persistently infected (PI) animals - or for a short period (transiently infected animals). 3 LIVESTOCK MATTERS WORKING TOGETHER FOR A HEALTHIER FUTURE...

5 BOVINE ABORTION DIAGNOSIS Abortion is a notifiable disease, so every farmer is obliged to report each case... Each case of abortion should be reported to the Department of Agriculture by sending a blood sample to the brucella laboratory, or by sending a foetus and placenta to the local Regional Veterinary Laboratory (RVL). The overall diagnostic rate is low at 30%. PREVENTION A. Biosecurity Biosecurity includes measures to prevent the entry of new infections to a farm, while biocontainment refers to strategies to minimise the spread of existing infections between various groups of cattle. Animals must be isolated for at least three weeks after purchase and be tested, treated or vaccinated for diseases of interest before mixing with animals in the new herd. Purchase of maiden heifers rather than springers reduces the risk of abortion. Exposure to a causal agent already on your farm by a naïve purchased animal can also result in abortion in that animal. Spoiled or musty feed or roughage should not be fed to pregnant animals for fear of fungal abortion or Listeriosis. Avoid soil contamination of grass during silage making, as this predisposes to Bacillus licheniformis abortion. Organisms such as Salmonella may persist for many months in slurry, so slurry should be spread on arable/silage fields rather Any animal suspected of aborting should be isolated until a few days after she has cleansed and all visible vaginal discharges have ceased. The isolation box should be carefully cleaned and disinfected after use. than on land that will be grazed soon. All farms, with or without a Neospora problem, should minimise contact between dogs and cattle, particularly at calving. Dogs should be kept away from feed storage areas and feeding areas, and ideally should not be allowed to defecate on pasture. B. Vaccination Vaccines against Leptospirosis, IBR, BVD and Salmonellosis are available and are commonly used. For maximum benefit, animals should be vaccinated before being exposed to infection, e.g. heifers should be vaccinated against Leptospirosis at as young an age as is recommended by the manufacturers. Many farms organise their booster vaccination routines to administer BVD and Leptospira vaccines in spring, when most of the herd is between calving and breeding and administer the Salmonella vaccine in autumn, when the cow is in mid-pregnancy (August or September). Much of the information in this article was provided by Donal Toolan V.S. Regional Veterinary Laboratory Kilkenny CASE STUDY Michael Marnell farms a fifty cow dairy herd in Pollagh, Kilmanagh Co Kilkenny. Over a number of years he was having occasional cows aborting, however in the winter of 2008 he had a number of cows aborting at approximately seven months. He consulted with Paschal at Ormonde Veterinary and two foetuses were submitted to Kilkenny regional laboratory. Salmonella dublin was isolated from both these. Following consultation with Paschal it was decided to implement a vaccination programme and all breeding stock was vaccinated with Bovivac S vaccine. This contained the problem and has resulted in greater calving rates subsequently. Michael highlights the importance of investigating such problems sooner rather than later. Initiation of this vaccination programme represented a significant investment but this has been repaid handsomely since. Farmer Michael Marnell FIGURE 1. FREQUENCY AND DETECTION OF CAUSAL AGENTS Agent Peak time of abortion Other possible signs Main source of infection Frequency* Brucellosis Seven to nine months Weak calves at birth Inflammation of the testicles in bulls A. pyogenes Any time Found in mastitis and womb infections Often a secondary invader Salmonella dublin Seven to eight months High temperature Severe diarrhoea often with blood Leptospira Five to six months Milk drop Weak calves Poor return to service Carrier cattle - Environment, gut and tonsils of healthy cattle 5.7% Faeces of carrier cattle 4.6% Urine of carrier cattle 4% Bacillus licheniformis Seven to nine months None Soil contamination of grass during silage making 2.7% Listeria/fungal Seven to nine months None Mouldy silage 1.8% Neospora Four to five months Recurrent abortion may occur, with a normal pregnancy in between Aborted foetuses may be mummified BVD Virus Any time Early embryonic death Ill thrift Diarrhoea Mucosal disease *Frequency in Ireland in 2008 Mostly from dam; some from feed contaminated with dog faeces Carriers shedding virus; either transiently infected or persistently infected 6% 5.8% WINTER 2010 ISSUE LIVESTOCK MATTERS 4

6 JOHNE S DISEASE ARTICLE BY: DONAL LYNCH MVB Donal Lynch Veterinary, Tullamore, Co.Offaly JOHNE S DISEASE In The Beef and Dairy Herd Johne's disease is a chronic debilitating disease of both dairy and beef breeds of cattle. The disease is caused by a bacterium, Mycobacterium avium subspecies paratuberculosis (or Map for short). In 2005 a prevalence study carried out in Ireland estimated that approximately 10% of herds were affected by Johne's disease. Veterinary Surgeon Donal Lynch XLVets Practice Donal Lynch Veterinary, Tullamore, Co.Offaly At herd level Johne's is a cause of significant economic loss due to reducing the productivity of the animal i.e. reduced milk production along with reduced fertility in the dairy cow and reduced beef performance and fertility in the suckler cow. In an individual animal the symptoms of Johne's disease are non-specific and include: Poor Body Condition Score (BCS) Reduced milk yield Prolonged periods of scour Bottle jaw (similar to that seen with liver fluke) Since symptoms of Johne's disease could easily apply to a number of parasites such as liver or rumen fluke and stomach worms, no response to treatment of these conditions would increase the suspicion of Johne's disease. Typically Johne's disease is seen in older animals (over 3 years old) but it can be seen at any age. Bottle jaw may be as a result of Johne's disease. Donal Lynch MVB Vet Tullamore Possible causes of persistent scour in cows Liver fluke Rumen (stomach) fluke Stomach worms Salmonella Mucosal disease caused by BVD 5 LIVESTOCK MATTERS WORKING TOGETHER FOR A HEALTHIER FUTURE...

7 JOHNE S DISEASE Johne's disease in your herd... Poor condition may be as a result of Johne's disease....what to do if you believe you may have a Johne's disease problem in your herd... Remember, every herd problem starts somewhere so even if you have only one animal showing signs it is worth investigating. Consult with your vet for advice; they will be able to take a number of samples to confirm presence of disease. Dung and blood samples are useful to detect the presence of Johne's disease in an animal. Dung samples are very specific, but are very time consuming with results taking up to 16 weeks. Blood samples are somewhat less accurate and need to be interpreted along with the clinical picture. What to do if you have confirmed Johne's disease on your farm? If Johne's disease is confirmed in your herd you will need to alter your management practices to rid your herd of the disease. To understand such a programme it is necessary to understand how Johne's is transmitted. An infected animal sheds the JOHNE S CONTROL PLAN Blood test all breeding animals and divide into management groups as follows: Cull animals: all positive animals showing clinical signs should be culled. High risk * : All positive animals not showing clinical signs should be dung sampled and considered to be high risk, any animals that show clinical signs even if negative on blood test should be included here, and any animals that were bred from cows that now prove positive are also considered high risk. Lower risk: All animals that test negative on the blood and show no signs of disease and are bred from negative dams. * Animals of unknown status should be considered high risk until status established. Minimise risk of spread: Attend all cows calving and wash away any faeces that lands on the calf immediately. Remove calves from the calving pens immediately following birth. Only feed colostrum from known negative cows (i.e. those in the low risk group) to your calves. Prioritise calves that will be kept for breeding. Manage youngstock grazing to minimise contact with potentially contaminated dung. Graze calves on paddocks that have not been grazed by older animals that year, and have not had slurry spread that grazing season. Control in the beef suckler herd will be limited to culling high risk cows, and if this can't all be done in one year ensure that only offspring from low risk cows are used for breeding. Ongoing monitoring of the herd: All breeding animals should be blood tested every year and categorised into risk groups; this is because an animal bacteria in body secretions, the most significant of which are milk (and colostrum), and faeces. The younger an animal, the more likely they are to pick up the disease. For this reason calving time and the first few weeks of age are the highest risk period. The elements of a Johne's control plan will include: that tests negative this year may prove positive in the future. Be vigilant for clinical cases and address immediately. Reduce the risk of buying in Johne's disease: Enquire about the Johne's status of the herd from which you intend to buy. Blood test all bought in breeding animals for Johne's and if possible blood test their dams before purchasing. There is no vaccine available for Johne's and control and eradication is based on management practices supported by diagnostic testing. As all herds are different you will need to consult with your own veterinary surgeon for specific advice in relation to your herd. You can minimise the risk of Johne's becoming a problem in your herd by: Good hygienic practices at calving. Proper colostrum management. Following advice when buying breeding animals. Following up on any animals that show signs consistent with Johne's disease. Persistent scour may be as a result of Johne's disease. WINTER 2010 ISSUE LIVESTOCK MATTERS 6

8 CRYPTOSPORIDIUM Asmall, spring calving dairy herd was investigated for diarrhoea in calves at 5 to 15 days old, midway through the calving season. The farmer had noticed that calves were getting scour and not responding to his on-farm routine protocol of electrolytes and oral antibiotics. His older calves were not thriving as they should. He had vaccinated the cows during the dry period for Rotavirus and Coronavirus. Faecal samples were taken from affected calves. The results showed a heavy burden of Cryptosporidium. Cryptosporidium Infection incalves... KEY POINTS Cryptosporidium parvum is usually only one component in an overall syndrome causing diarrhoea in calves. Cryptosporidium is a zoonosis i.e. it can cause serious diarrhoea in man. There is no definite protocol to cure Cryptosporidium - it can only be controlled Gerard Gilligan and prevented. Veterinary Surgeon Sean Coffey XLVets Practice Mulcair Veterinary Clinic, Cappamore, Co.Limerick What is Cryptosporidium? Cryptosporidium is a protozoan parasite similar to coccidia that is extremely common in the environment. It is becoming an important infectious agent causing diarrhoea in young, immunosuppressed mammals including man. It is prevalent worldwide. In a disease outbreak many animals contract the disease and it causes ill thrift and poor weight gain but with heavy burdens it can cause debility and death. What is the life cycle of Cryptosporidium? Adult animals (carrier animals) excrete oocysts in low quantities in their faeces without showing clinical signs. Oocysts are like small thick walled eggs, they are resistant to many disinfectants and are very resistant in the environment. These oocysts infect newborn calves at, or soon after birth. Once infected the oocysts enter the lining of the gut causing severe damage and multiplying at the same time. Within four days of infection, calves will start shedding vast quantities of oocysts into the environment infecting other calves in the vicinity rapidly. In a short period of time there is massive environmental contamination. Old housing, with cracks and crevices, are hard to reach with disinfectants 7 LIVESTOCK MATTERS WORKING TOGETHER FOR A HEALTHIER FUTURE...

9 CRYPTOSPORIDIUM SEAN COFFEY MVB Our dairy client accepted that there was no quick solution to his Cryptosporidium outbreak. He set about treating his affected calves electrolytes, a broad spectrum antibiotic and Halocur... How do you diagnose Cryptosporidium? Faecal analysis is the key to diagnosing cases of Cryptosporidium. At least five affected calves should be sampled ideally at around 12 days of age. Samples should be taken directly from the calf and not from the ground. Mixed infections are extremely common and significant as Cryptosporidium overlaps with Rotavirus as a cause of scour and also BVD can be blamed for suppression of the immune system thereby allowing Cryptosporidium to gain a stronger foothold in calves. Calf with Cryptosporidium How do you treat cases of Cryptosporidium? There is no cure or easy solution to Cryptosporidium. Cases must be treated for the symptoms that you see. Dehydrated calves must be given oral electrolytes 2-3 times per day. They must be kept warm and dry. While antibiotics have no effect on Cryptosporidium there may be a role for the use of broad spectrum antibiotics in case of a mixed infection with bacteria. Halofuginone Lactate (Halocur-Shering Plough Intervet) should be given at 2ml per 10 kg bodyweight for seven consecutive days directly after feeding or in milk. The entire group of in-contact animals should be treated at the same time to reduce oocyst shedding. Once an outbreak has been diagnosed and calves are being treated for the disease it is also necessary to treat all newborn calves with Halocur for seven days. There may also be a role for gut protectants and probiotics in the treatment of Cryptosporidium. PREVENTION IS BETTER THAN CURE... Prevention is definitely better than cure as there is no vaccine available and there is only a moderate response to licensed medication. Maternal colostrum is the obvious but essential start for calves in the first hours of life. Equally a healthy cow that has had appropriate parasite control; that is in good body condition and that has had decent nutrition and minerals during the dry period. As Cryptosporidium is only part of a mixed gut infection it is important not to neglect the use of vaccines to control bacterial and viral gut infections i.e. Rotavirus, Coronavirus, Salmonella, E.coli. Control of BVD will reduce the severity of the scour as the calves immune system is better prepared for any infectious agent. THE MAJORITY OF CALF SCOURS ARE CAUSED BY SIX ORGANISMS: (a) Viruses; Rotavirus and Coronavirus (b) Bacteria; E.coli and Salmonella (c) Protozoa; Cryptosporidia and Coccidia. Reports from the veterinary laboratories indicate that Cryptosporidium and Rotavirus are the most frequently found organisms associated with calf scours. Once our dairy client accepted that there was no quick solution to his Cryptosporidium outbreak he set about treating his affected calves with electrolytes, a broad spectrum antibiotic and Halocur. He initiated a protocol for newborn calves revolving around good hygiene at calving, followed by decent colostrum intake, rearing in different areas of the farm from infected calves and prophylactic treatment with Halocur from Day 0 to 7. There were no fatalities but affected calves never achieved weight gain of their earlier comrades. There were reduced clinical signs in the calves born later in the calving season due to the initiated protocols. Blanket disinfection and drying of the calving pens took place during the summer. The farmer's major costs were time and medicines. Calf with scour Since infective oocysts are carried in faeces it is a good idea to have cows teats, udder and lower limbs relatively clean around the time of calving. The oocysts are resistant to many commonly used disinfectants but strong ammonia based disinfectants are effective when used on a clean surface. Oocysts will live for months in cool damp conditions but will die in dry conditions, therefore all calving pens and calf housing should be cleaned out once calving is finished, disinfected and left to dry over the summer. IMPORTANT POINT There is evidence that the infection rate is much higher than the rate of clinical disease. Modern calf houses are easier to clean and disinfect WINTER 2010 ISSUE LIVESTOCK MATTERS 8

10 NEOSPOROSIS DONAL MURPHY MVB MRCVS Neospora caninum was first recognised in the world in 1988 and was initially misidentified as Toxoplasma gondii... NEOSPOROSIS An emerging problem in Irish herds... During the past decade, Neosporosis has emerged as an important reproductive disease in cattle throughout the world. Abortion, occurring in the middle of the gestation period i.e. between the fourth and seventh months of pregnancy, is the primary clinical sign. It is now one of the most commonly diagnosed causes of cattle abortions in Ireland. Veterinary Surgeon Donal Murphy XLVets Practice Sliabh Luachra Veterinary Centre, Co.Kerry The Cause It is caused by a protozoan parasite (a microscopic organism slightly bigger than a bacterium) called Neospora caninum. It was first recognised in the world in 1988 and was initially misidentified as Toxoplasma gondii which causes abortions in sheep. Neospora is similar to Toxoplasma in that they both have a final host, the dog in the case of Neospora and the cat in the case of Toxoplasma. The big difference between them however is that Toxoplasma is potentially very serious for humans, whereas Neospora is not. Life Cycle To understand how cattle pick up the infection, and how we can control it, we must first look at the life cycle of the parasite. The final host is the dog and the dog passes out oocysts in its faeces. The oocyst is like the egg of the parasite, and it can survive for months in the environment, even in harsh conditions. The cow comes along and eats the oocyst on its food or water, which has been contaminated with dog faeces. When the Neospora gets into the cow it goes to the uterus and infects the foetus (calf) and the placenta. The life cycle is completed then when a dog eats an infected placenta ( cleaning or afterbirth ) or when he eats an infected calf carcass, or an aborted calf carcass. Diagnosis Diagnosis of Neosporosis is done by blood testing cows which have aborted or by Laboratory examination of the aborted calf. A bulk milk test will give an indication of the level of infection in the herd. Binscarth Farms 9 LIVESTOCK MATTERS WORKING TOGETHER FOR A HEALTHIER FUTURE...

11 NEOSPOROSIS FACTS ABOUT NEOSPOROSIS Once infected, cows may abort only once, or they may abort frequently. Infected heifer calves may look normal, but 20% of them will abort at least once in their lives. Each calf born to these animals is likely to be infected. The same thing happens to the next generations of heifer calves born in the herd. Infected calves may also be stillborn, or may be weak at birth and die in the first few days. Bulls do not spread the disease. Even though it has never been conclusively proven that foxes are involved in the spread of Neospora, in an Irish context it is quite likely that they are. SPREAD IN CATTLE Cattle become infected in 2 ways Horizontal spread occurs when the cow eats the oocysts which the dog has passed in its faeces. This can occur on grass, from a feeder wagon, or when cattle eat concentrates which might be contaminated by dog faeces, or when they drink contaminated water. When the cow becomes infected and the infection passes into her uterus she may abort. If a farm has experienced a lot of abortions due to Neospora in a short space of time, it is most likely that this is the way the infection spread. Vertical spread occurs when the infection passes from cow to calf in the uterus. Sometimes the calf in the uterus dies as a result and is aborted, but very often the foetus does not die and is born as an apparently normal calf. However, this calf is carrying the infection and will pass it on to her own offspring which may then subsequently abort. In this way the infection is perpetuated in the herd, and will remain in the herd for generations. CONTROL (1) To control horizontal spread Keep calving pens clean and dry and disinfect regularly. Prevent dogs from coming in contact with cows and heifers at calving time. Carefully dispose of placentas, aborted foetuses and stillborn calves so that dogs or foxes cannot feed on them. Try to stop the possibility of dogs or foxes defaecating anywhere near cattle feed or water supplies, especially the feed ingredients of a feeder wagon. Don't shoot the dog!!! Dogs pass oocysts in the faeces for only 3 weeks after they become infected. (2) To control vertical spread To control vertical spread you must first identify which cows are carrying the parasite. This will include the cows which previously aborted due to Neospora. You can identify the infected cows by blood testing all the female breeding animals. Do not breed replacement heifers from these cows. In a dairy herd you should put these animals in calf to a beef breed, and the progeny should be fattened and slaughtered. In this way you break the cycle of infection. Blood test any bought-in cows and follow the same guidelines if they prove positive in the blood test. WINTER 2010 ISSUE LIVESTOCK MATTERS 10

12 Welcome to the first XLVets readers competition. YOUR CHANCE TO WIN... We have XLVet fleeces to give away to the first three correct entries drawn at random after the competition closes. WINTER 2010 ENTER TODAY To enter, simply answer the five questions below and complete your details on the entry form. All the answers can be found in the articles in this issue of the magazine. Details of where to send your entry can be found below. GOOD LUCK... A winner will be chosen from all the correct entries received before the closing date, Friday 21st January Winners will be revealed in the next issue of XLVets Ireland Livestock Matters. one... two... Approximately what percentage of herds were infected with Johne s disease in Ireland in 2005? 5% 10% 15% What are the two organisms most frequently associated with calf scours in Ireland? My details Name Address three... four... What is the main source of infection of bovine abortion caused by Listeria? What other animals can act as a source of neospora for cattle? Daytime Telephone Number XLVets Practice Name five... How many member practices are there in XLVets Ireland? I would like to receive further information from XLVets by I do not wish to receive further information from XLVets Send your completed entry to: Farm Competition No.1 XLVets Ireland, Dromsally, Cappamore, Co.Limerick The editor s decision is final and no correspondence will be entered into. The actual fleeces supplied may differ slightly from the one pictured. Ireland