Livestock SCANNING ULTRASOUND. Inside this issue: SPRING EDITION 2011 WORKING TOGETHER FOR A HEALTHIER FUTURE.

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1 SPRING EDITION 2011 Livestock WORKING TOGETHER FOR A HEALTHIER FUTURE Inside this issue: 3.25 MATTERS COLOSTRUM MANAGEMENT We investigate the importance of calves receiving high quality colostrum to prevent calf disease, the key to calf survival. ULTRASOUND SCANNING How to get more from this ever improving technology. 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 SPRING 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 03 BVD Case Study - Diagnosis and Control: Michael Sexton, Riverview Veterinary Group, looks at the diagnosis of BVD and gives advice on controlling the disease. REPORTS 05 Colostrum Management: Caitriona Stuart, Donal Lynch Veterinary, reports on the importance of calves receiving high quality colostrum to prevent calf disease. 07 Ultrasound Scanning: Michael O Meara, Gortlandroe Veterinary Clinic, reports on why ultrasound scanning has emerged as an important tool for pregnancy diagnosis and the service it can provide for better herd management. CONTENTS DAIRY FEATURE 09 Preventing Milk Fever in dairy cows... Vet Kieran O Mahony, Glen Veterinary Clinics, investigates this typically seen disease that affects mainly freshly calved cows. 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 BVD CASE STUDY MICHAEL SEXTON MVB I explained the AHI document to the client and showed how his herd was in effect an S5 herd, meaning active infection... BVD CASE STUDY DIAGNOSIS AND CONTROL One of the more progressive clients of the practice contacted me last March concerned that there was something amiss with his herd. He is milking about 100 cows in South Cork and has always had, what could only be described as, chronic sub-optimal fertility results i.e. circa 20-25% empty rate almost every year. By most other metrics - calf mortality, S.C.C., mastitis rates etc - this is an above average herd. The farmer enquired as to whether BVD infection could have a role to play. Veterinary Surgeon Michael Sexton XLVets Practice Riverview Veterinary Group, Co.Cork INVESTIGATING I arranged to have a BVD Herd Scan performed. This involved a bulk tank milk sample to be checked for BVD antibodies (ELISA) and virus (PCR) as well as 5-10 individual juvenile (>9 month old) BVD antibody tests. By the middle of March there were many cows yet to calve and it would therefore be too soon to do the bulk milk tests. The farmer was still anxious to proceed and do the juveniles. On 16/03/2010, six January 2009 born heifers were blood tested for antibodies. Five had sero-converted, three very strongly and one was still naive (#1162). It was decided in our lab, Animal Health Laboratories Ireland Ltd (AHLI), to test 1162's sample for virus. The result came back as positive! This heifer appeared no different to the others in the same batch; however the farmer insisted that she was being held back by something all year, which he now concluded must be BVD was now confirmed as a transiently infected animal (TI). Three weeks later, 07/04/2010, both 1162 and her Dam 249 were tested for both antibody and virus by blood ELISA. 249 was positive for antibodies and negative for virus was positive for virus and negative for antibody - the exact same results as three weeks previously! We could now declare 1162 as a persistently infected animal (PI).1162 was immediately destroyed. Her dam was the only family member in the herd. Also the farmer had isolated 1162 between tests as we were suspicious that she was a PI, but needed the second set of results to confirm the PI status. CONTROLLING I explained the AHI document to the client and showed how his herd was in effect an S5 herd, meaning active infection. He decided he wanted the whole herd tested individually and that there was no point doing the bulk milk tests which would have completed the BVD Herd Scan stage. Before embarking on the herd wide testing I again pulled out the AHI document and impressed upon him the importance of enhanced biosecurity, vaccination, monitoring, costs of testing and the fact that despite our one PI already, that he may not discover any more PI's. I was talking to the converted. Shortly afterwards all the animals on the farm, except for the calves born in 2010, were blood tested with the Idexx ELISA antigen test kit and no further virus positives were found. In November 2010, all the 2010 born calves were tested. All tests were negative for BVD virus. MONITORING The herd is closed. The 2011 and 2012 crop of calves will also be tested in due course. Any new purchased stock (unlikely) will be screened for the virus as well as any subsequent offspring. 3 LIVESTOCK MATTERS WORKING TOGETHER FOR A HEALTHIER FUTURE...

5 BVD CASE STUDY

6 COLOSTRUM CAITRIONA STUART MVB Healthy cows produce a better quality colostrum, while concurrent disease, poor nutrition and a shortened dry cow period reduces colostrum quality. Veterinary Surgeon Caitriona Stuart XLVets Practice Donal Lynch Veterinary, Tullamore, Co.Offaly Colostrum Management in Newborn Calves... Colostrum - the most important factor in preventing calf disease is to ensure calves get enough high quality colostrum Colostrum - the key to calf survival The structure of the cow's placenta does not allow whole proteins to pass across to the calf before birth. A newborn calf therefore has none of the immunoglobulins (Ig) that are essential to protect it against disease. Colostrum is the milk produced by the cow in the days immediately after calving and it is rich in protective immunoglobulins, as well as containing nutrients, vitamins and minerals. A calf will begin to produce its own Ig at approximately 10 days of age, with normal levels reached by 8 weeks of age. Before this age the newborn calf is totally dependent on the immunoglobulins contained in colostrum to protect it against infection. The earlier and the more the calf sucks the greater the amount of immunoglobulin absorbed. 5 LIVESTOCK MATTERS WORKING TOGETHER FOR A HEALTHIER FUTURE...

7 COLOSTRUM Colostrum - cow factors Immunoglobulins are actively transferred from the cow's blood to the udder in the weeks before calving. IgM, IgA and IgG are all involved, however IgG is by far the most numerous. The level of immunity provided by a cow's colostrum reflects her own immune status. A mature cow's colostrum tends to be more concentrated and provide protection against a wider range of disease than a heifer's would because the cow will have been exposed to more disease in the main herd. Healthy cows produce a better quality colostrum, while concurrent disease, poor nutrition and a shortened dry cow period reduces colostrum quality. Cows that have been vaccinated against specific diseases eg scour vaccines will transfer this immunity to the calf via the colostrum. The vaccination should be completed 4 weeks before calving to allow maximum production of Ig and its transfer from the cow's blood to the colostrum. CALF FACTORS In the first hours of life the calf's gut is very permeable to the large Ig proteins and the enzymes that would normally digest these proteins are not yet present. This allows the immunoglobulins to pass whole through the gut wall into the calf's bloodstream. The maximum ability to absorb these proteins lasts about 6-8 hours. It then declines until little transfer is possible after hours of age. However, even after this age the nutritional value of colostrum is important to the calf, and it also provides local immunity in the gut that helps protect against E.coli and rotavirus. Colostrum should therefore be fed to the calf for several days after birth. To achieve adequate colostral immunity a calf should receive 2 litres in the first hour after birth and 5 litres in the first 6 hours. The ability of the calf to suck this amount depends on how active he is after birth, as well as on the size and conformation of the udder and teats. A cow that is down after calving or one that doesn't take to the calf will also affect colostral intake. If you are in doubt about the amount the calf received the cow should be milked and the calf tube fed.. Big pendulous teats are difficult for newborn calves to suck resulting in poor colostrum intake Colostrum is essential for healthy calves Storing Colostrum Colostrum quality varies with time from calving so first day colostrum from cows rather than heifers should be stored. Keeping it in one litre packs allows it to be thawed effectively. The best method of thawing is to immerse the packs in warm water until they reach body temperature. They should not be microwaved or heated in boiling water because this will destroy the Ig proteins. While the best source of colostrum for a calf is from its own mother, stored colostrum from another healthy cow on the same farm will provide adequate Ig levels once it is fed in the correct amount. Colostrum from neighbouring farms should be used with caution because of the danger of spreading disease. It is not always possible to get the required amount of good quality colostrum from the dam to feed a newborn calf. It is recommended therefore to keep a store of MEASURING COLOSTRUM INTAKE ZST Readings colostrum to feed to newborns in these cases. Colostrum will keep for at least 6 months, and probably several years, in the freezer. Measuring Colostrum intake... Good quality colostrum is thick and pale yellow in colour. It should not contain blood or mastitis clots. To assess the quality and quantity of colostrum absorbed by a calf laboratory tests can be done. The most common of these is the zinc sulphate turbidity (ZST) test, which is performed on a blood sample taken from a calf at least 24 hours old. This test is widely available in most veterinary laboratories, such as the regional veterinary labs. A low ZST reading may mean that the calf didn't receive enough colostrum, or that the colostrum it did get was of poor quality. 0-5 None Inadequate 6-15 Minimal Minimal Moderate Moderate 24+ Adequate Good To ensure adequate colostrum intake tube feed weak calves Amount of absorption Level of protection Colostrum Management and Johne s Disease Proper management of colostrum is vital in preventing the spread of Johne s disease within a herd. Feeding colostrum from an infected cow to calves is the single greatest risk factor in spreading the disease to the herd's potential replacement breeding animals. The practice of pooling colostrum allows the infection to spread from a single infected cow to a large number of calves. To prevent this only colostrum from its own mother or stored colostrum from a single mature (> 8 years) cow that is not showing any clinical signs of Johne's should be given to a calf. SPRING 2011 ISSUE LIVESTOCK MATTERS 6

8 ULTRASOUND MICHAEL O MEARA MVB Pregnancy can be detected by ultrasound scanning in cows and heifers from about 25 days. Early pregnancy scanning also acts as an early warning system... ULTRASOUND SCANNING Get more from this ever improving technology... Ultrasound scanning is widely used on Irish farms as a tool for pregnancy diagnosis. Improvements in equipment and upskilling of operators however means we can get far more from this service leading to more cows in calf and better herd management. Veterinary Surgeon Michael O Meara XLVets Practice Gortlandroe Veterinary Clinic, Co.Tipperary After calving, the cows uterus undergoes involution, a process which takes about 3 weeks. This may be delayed by factors such as clinical/subclinical milk fever, retained afterbirths and difficult calvings. Further changes to the lining of the uterus mean that most cows need at least 42 days before they are ready to resume reproductive activity. Ultrasound scanning of cows pre breeding is a useful tool to assess the progress of involution and to identify potential problems such as non cycling cows and those with uterine infections. Non cycling cows early in the breeding season may simply need more time to resume reproductive activity but some will be suitable for hormonal stimulus. A high proportion of non cycling cows in a herd may indicate problems with nutrition or mineral deficiencies. Early investigation and treatment of such problems are vital for a successful breeding season. Cows found to have uterine infections will usually need treatments such as uterine flushing or induction of heat. Pre breed scanning is also useful to determine the stage of the oestrus cycle which aids heat detection and allows more appropriate timing of hormonal treatments. The pre breed scan can also be used to select the cows most suitable for the use of high value AI semen. Pregnancy can be detected by ultrasound scanning in cows and heifers from about 25 days. However up to 10% of these pregnancies will be lost so it is more useful to confirm pregnancy from day 35 post breeding. Old Modern housing, portable with cracks scanners and work crevices, well at farm level are hard to reach with disinfectants 7 LIVESTOCK MATTERS WORKING TOGETHER FOR A HEALTHIER FUTURE...

9 ULTRASOUND 38 day pregnancy Early pregnancy scanning also acts as an early warning system where problems such as a sub fertile bull or issues with AI will be identified quickly and appropriate action can be taken. Scanning of early pregnancies will identify early embryonic deaths and these cows can be brought back into heat much more quickly than would naturally occur. A higher than expected rate of early embryonic deaths may indicate the presence of diseases such as BVD, neospora, leptospirosis or nutritional imbalances. Too often these problems are only identified at the end of the breeding season leaving little time for action to be taken. Determination of the age of the pregnancy can be accurately assessed up to about 110 days of gestation. This is very valuable information for herd management as it allows appropriate dry periods, better nutritional management and ideal timing of vaccinations. It is also useful if surplus stock are to be sold. Ultrasound scanning can also be used to identify twin pregnancies. These are easiest to identify before 90 days of gestation. Cows carrying twins can then be selected for longer dry periods, better nutrition and more attention at calving. Improvements in ultrasound equipment and operator training means that sexing of the bovine foetus is now possible between days of gestation. This information is useful for calving management and selection of animals for sale or culling. 60 day pregnancy Ultrasound scanning is commonly used on a herd basis at the end of the breeding season. Although the size of the foetus and its position deep in the abdomen limits the information available from this procedure it is still useful to identify non pregnant cows which can then be culled or milked on to enter the next breeding season if suitable. Vets frequently comment on the high numbers of pregnant cows seen in abattoirs highlighting the importance of confirming non pregnancy in cull cows. PRE BREEDING SCAN Identify non cycling cows Identify uterine infections Identify stage of reproductive cycle Select cows for expensive AI semen EARLY PREGNANCY SCAN Identify non pregnant cows Identify early pregnancies Identify early embryonic death Age pregnancy up to day 110 Identify twins Sexing of embryo from day LATE PREGNANCY SCAN Identify non pregnant cows to milk on Avoid unnecessary culling Group of XLVets at a recent scanning course given by Italian expert Dr Giovanni Gemini Modern calf houses are easier to clean and disinfect SPRING 2011 ISSUE LIVESTOCK MATTERS 8

10 DAIRY FEATURE ARTICLE BY: KIERAN O MAHONY MVB Glen Veterinary Clinics, Tipperary Town, Co.Tipperary Preventing Milk Fever in dairy cows 'Milk Fever' is typically seen in freshly calved cows. Cows with clinical milk fever are unable to stand, due to a deficit of calcium in the bloodstream (hypocalcaemia). Veterinary Surgeon Kieran O Mahony XLVets Practice Glen Veterinary Clinics, Co.Tipperary Calcium is required for muscle contraction. If the muscles can't work, the animal can't stand up. The heart muscle is affected, so the heart becomes less efficient, beating faster and with less power. Stomach and gut muscles likewise, so all digestion slows down. The uterus muscle can't contract as effectively, so shrinkage of the uterus after calving is delayed. The small muscle at the teat sphincter is affected meaning an increased risk of mastitis. A cow in an advanced calcium deficit is dull, lifeless, and cold. Untreated, she will eventually die. At calving, the demand for calcium increases dramatically due to new milk production. This calcium requirement is provided in part by the diet, but more importantly by the cow's own calcium stores in her bones. It is vital that release of these stores is encouraged in the final weeks before calving. The inclusion in the diet of trace elements such as Vitamin D3 and Magnesium helps achieve this release, and these are essential components of a good dry cow mineral. The dry cow diet should be as low as possible in calcium. We are all familiar with the 'downer cow' milk fever case, but just as important are the cows suffering from sub-clinical hypocalcaemia. These Binscarth cows Farms won't go down, but will suffer milder forms of all the symptoms, mainly poor uterine tone, poor teat sphincter function, poor digestion. On a herd level this can lead to more cases of retained afterbirths (and subsequent infertility), more cases of mastitis (and increased SCC), and more cases of displaced abomasums (LDA/RDA). Treatment for a clinical case involves infusion of calcium into the vein combined with other supportive therapy. However, prevention should be the focus, and for this, attention to the management and diet of cows in the transition period is essential. The transition period begins 2 to 3 weeks before calving, and continues until 2 to 3 weeks after calving. In this period the cow should be fed as consistent a diet as possible. Due to stresses at calving time, food intake drops significantly. Dry matter intake has been found to decrease by as much as 30% in the week before calving. Energy requirements then rise as the cow joins the herd and produces large quantities of milk. This can lead to a Negative Energy Balance (NEB), where energy output exceeds energy intake. Because feed intake before calving is significantly less than after calving, cows should be fed a high fibre diet, to encourage rumen fill, keeping the rumen large so that when increased feed intake is required, the rumen is ready. Bacteria in the rumen are essential for digestion. By feeding a tailored transition diet, these bacteria are ready and waiting once lactation begins. 9 LIVESTOCK MATTERS WORKING TOGETHER FOR A HEALTHIER FUTURE...

11 DAIRY FEATURE Herd problems associated with Hypocalcaemia: Downer Cows Retained afterbirths Displaced Abomasums Mastitis Prevention of Hypocalcaemia: Establish a consistent transition diet Feed low calcium pre-calving Feed high fibre diet pre-calving (straw, baled silage) Feed a good quality dry cow mineral, high in magnesium and vitamin D3 Kieran O Mahony with John O Dwyer Case Study: John O Dwyer John O'Dwyer milks 80 cows on his farm in Donohill, Co.Tipperary. The cow's average annual milk yield is 1500 gallons, and the calving period runs from 1st February to 1st May. In the years preceding 2008 John's herd suffered an above average incidence of downer cows due to milk fever. The vet would be out to six or seven cows a year explains John, sometimes twice or three times to one cow. (34% Barley, 33% Soya, 33% Distiller's Maize). The cows are calving down in better condition and they are healthier. The Dry Cow Mineral contains 15% Magnesium which aids the release of calcium from the cow's own bone stores, and the straw maintains rumen fill. The spacious cow shed has its benefits too. Cubicle space is optimal, and there are surplus cubicles, which is important for cow comfort. All passageways are wide and potential bottlenecks at each end and around water troughs are wider. There is also plenty of feed trough space so overcrowding is avoided. Because feed intake before calving is significantly less than after calving, cows should be fed a high fibre diet, to encourage rumen fill Kieran O Mahony The cows are fed a Total Mixed Ration In 2008 John built a new shed for the dry cows and purchased a diet feeder. He started to feed a TMR to the cows pre-calving and the effect has been obvious. The springs of 2009 and 2010 have come and gone without a single case of milk fever. John explains, The cows are fed a daily diet consisting of 28kg Silage, 2.5kg Straw, 125g Dry Cow Mineral, 0.7kg Soya Bean Meal, and 0.6kg Ration Wide passageways at each end of the shed SPRING 2011 ISSUE LIVESTOCK MATTERS 10

12 Welcome to the spring XLVets reader s competition. SPRING 2011 YOUR CHANCE TO WIN... We have an XLVets fleece to give away to the first correct entry drawn at random after the competition closes. ENTER TODAY To enter, simply answer the four 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, Saturday 30th April Winners will be revealed in the next issue of XLVets Ireland Livestock Matters. one... What does NEB stand for? two... What does the ZST test check for? Winter 2010 Livestock Matters competition winner: Maurice Maher, Mountrath, Kilbeggan, Co.Westmeath My details Name Address three... four... For what is PI an abbreviation? List 3 herd problems associated with hypocalcaemia Daytime Telephone Number XLVets Practice Name 3. 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.2 XLVets Ireland, Dromsally, Cappamore, Co.Limerick The editor s decision is final and no correspondence will be entered into. The actual fleece supplied may differ slightly from the one pictured. Ireland