CONCLUSIONS FROM THIS MEETING. CALF HOUSING Control moisture Introduce air flow Eliminate draughts

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1 Central Scotland Dairy Monitor Farm Auchenheath Farm, Lanarkshire ML11 9XA Meeting report: Calf Pneumonia and Housing Ventilation With Jamie Robertson, University of Aberdeen & Charles Marwood, Clyde Vet Practice CONCLUSIONS FROM THIS MEETING CALF HOUSING Control moisture Introduce air flow Eliminate draughts CALF HEALTH Improve immunity Reduce the infection reservoir COMMUNITY GROUP RECOMMENDATIONS Open the skylights in the calf house Invest in a fan to move air in the calf house Shift the tap and sweep out moisture in the calf house Identify pneumonia strains Useful Contacts Gavin Ballantyne Monitor Farmer Sophie Kinnear- DairyCo facilitator Mobile: Mobile: gavballantyne@hotmail.co.uk sophie.kinnear@dairyco.ahdb.org.uk Archie Ballantyne Monitor Farmer Mobile: archie.ballantyne@hotmail.co.uk

2 Meeting Report: Fourth meeting of Lanarkshire Dairy Monitor Farm on 10 th December attended the fourth meeting of the Auchenheath Dairy Monitor Farm project, hosted by Archie and Gavin Ballantyne of Auchenheath Farm, ML11 9XA. Speakers Jamie Robertson, University of Aberdeen Charles Marwood, Clyde Veterinary Group Calf Pneumonia Meeting Objectives holistic approach to manage calf disease in calf housing other ways to reduce calf disease types of pneumonia we should be aware of Meeting Overview Auchenheath Village Hall 1. Farm Update- Gavin & Archie Ballantyne 2. Leatherjackets- Grant Conchie, SAC Lanark 3. Farm walk and talk on buildings and housing environment- Jamie Robertson, Aberdeen University 4. Pneumonia and calf health- Charles Marwood, Clyde Vet Farm Update (Gavin & Archie Ballantyne) Since the last meeting 20 cows have calved with no problems. There have been no major health problems in the calves; although two have had had scour. - Milk recording commenced on 18 th November with good results overall. Ketosis is low, heifers are milking well and a few cows are giving over 40litres which is pleasing. Metabolic profiling results have just returned but there hasn t been time for interpretation before this meeting. - Shed update: The Ballantyne s have decided on a new-build 180x100ft shed continuing on from the gable end of the existing shed, with 2 rows of cubicles and a centre feed passage. The new build will incorporate shed bays for calves, store and robots. Discussions with builders have commenced. - Colostrum testing programme has started with 5calves per week being blood sampled. Colostrum testing has shown that the cows are giving good colostrum following from good condition for calving with no health issues. Heifer colostrum is generally thought to be poorer quality; however Auchenheath testing shows heifer colostrum to be very good quality- lesson from this is that testing shows accuracy not fallacy. Testing also means surplus colostrum of good quality can be selected for freezing. When asked, few people were using colostrometers and were urged to take advantage of the free kits supplied at the meeting. Leather jackets (Grant Conchie, SAC) The Ballantyne s have had leatherjacket damage in the newly sown winter wheat and requested information on what to do. Leatherjackets are a significant problem this year, with around a third of the 2013 spring sown crops lost and now autumn crops heavily affected. Grubs are larger than normal and the impact on 2014 spring crops is a concern. Crops at highest risk are grass swards, ploughed up for cereals. Observation is critical to assessing the onslaught and extent of damage from leatherjackets. There are two forms of control; mechanical, after ploughing/cultivation, rolling in early morning can kill up to 50% of larvae; and chemical control, spraying is cost effective with larvae counts of more than 1m/ha in grassland and 600,000/ha in cereals. It is extremely important to spray sooner rather than later so vigilance is necessary from the date of sowing. The brand spray to use is DursbanWG, ensure the soil temperature is minimum 5 C, following label instructions and all guidance. Spraying can result in a 17% yield response in September, and 7% by February March. 80% dry matter increase can be achieved by early treatment of grass. LEATHER JACKET CONTROL Observe Sample fields Treat promptly

3 Housing with Jamie Robertson, Three key elements to improve calf housing environment The 3 elements as raised by Jamie can all be controlled, reduced, and improved to make any livestock housing work better for the health and productivity of the animals. 1- Moisture Controlling moisture reduces the presence of bacteria. Main sources of moisture: - Calves- urine, sweat, breath - Air moisture - Drinking and washing water (taps, troughs, leaks) Bedding Look at the calf shed with fresh eyes and identify the sources of moisture. Once they are identified, what can be done to reduce or preferably eliminate them? 2- Fresh air/ Air Flow - Kills bacteria 20% faster than still air - Removes moisture and heat (perfect environment for pathogens) - Creates zones of fresh air and removes dead air in the shed 3- Air speed How does air flow through the shed? Fast air speed can reduce temperature and make the environment cold, thus introducing temperature stress to the animal An animal under temperature stress uses energy (feed) to increase body temperature rather than towards growth An animal under temperature stress is more susceptible to bacterial threat as it s reserves are focussing on body temperature not disease resistance Auchenheath Calf Housing The current calf shed is a traditional stone building fitted with recycled stock board calf pens, straw bedded, with capacity for 20 calves. Calves are brought into the shed soon after birth, given colostrum and then onto twice-daily milk feeds with access to concentrates. They are shifted in batches to group housing in traditional stone buildings nearby, within 14 days of birth. All calves are kept in batches according to age, with the occasional anomaly. Moisture in the calf shed- There is too much moisture in the calf housing, mainly where the tap and washing facilities are located, with drains running through the centre of the building past each calf pen. The lack of fresh air (ventilation) at the top end of the shed means that any evaporation of excess moisture can only occurring using the energy from the body heat expressed from the calves, resulting in the calf environment being cooler. Jamie s thoughts - Cleaning the gutters every time the tap is turned to help reduce subsequent air moisture - Regular bedding changes will remove wet under-layers and certainly for biosecurity every calf should have a new straw bed. Ensure urine can drain out of the calf pens into the drainage channels. Drainage channels could be filled with sand or sawdust to absorb moisture as long as it is changed regularly to avoid build up of moisture and pathogens. Defra recommend 75% humidity and a relatively cheap hygrometer can be purchased to measure the shed environment before and after changes. 1litre of water/moisture on the floor will take one calf (<3weeks of age) 3.5hours to evaporate- directing energy form the food fed to the calf to keeping warm and not to growth or immunity Air Flow (The Stack Effect) The stack effect is the circulation of air according to temperature of the house. Hot air rises and cold air sinks and thus ventilation can be controlled by how temperature is managed in the house. Hot air needs to be able to escape the building at the highest point; otherwise it will condense and increase humidity, moisture and bacteria. To allow sufficient fresh air into the building, a corresponding inlet is required 2 (minimum) - 4 (ideal) times the outlet area. Ideally, sides of the building should be inlet areas but if not, be imaginative as to how to move fresh air from the inlet throughout the shed and out the outlet. Introduce new inlets/outlets, or consider fans/ducts etc. Refer to the DairyCo 2012 guide Dairy Housing a best practice guide Chapter 13 Ventilation

4 Air Speed (Temperature) Airspeed is not an issue at the doors of the calf shed, but air movement is not effective as the fresh air rushes straight through open doors and does not ventilate to the top end of the shed. The top end of the shed will be full of stale (dead) air. Jamie suggested we think of our sheds in red zones (dead air) and blue zones (fresh air) and picture how the air flows between red and blue. A simple fan at the bottom end would help shift fresh air and ventilate the top end. Jamie is currently doing some work on calf temperature and how cold affects growth rates. Preliminary results show that calves can withstand colder temperatures than we humans imagine, and in the UK it is high temperatures and high humidity in sheds that cause more problems than low temperatures. The low critical temperature for a calf in its first week is 15 C. Jackets can be used in cold conditions, and heat lamps are returning positive results at the previous dairy monitor farm in Brechin where priority calves under heat lamps are growing 15% faster (up to 1kg/day). They have used Quartz linear heat lamps ( 120 each) and can heat up to 20 calves, but position them carefully so the heat reaches the animal. When considering building materials, timber and plastic are warmer than concrete and steel. The Dairy Housing guide should be referred to for critical temperatures and simple designs. ACTION POINTS FOR AUCHENHEATH CALF SHED 1. Measure temperature and humidity in the shed 2. Create an outlet by opening the rooflights 3. Install a ground-floor fan at the doors to move fresh air to top end 4. Brush and squeegee all floor water out of the house 5. Wash less often with less water 6. Invest in heat lamps for priority (newborn or ill) calves 7. Can the water tap be moved to the doors? Jamie and the group also visited the slatted shed where male and cross calves are finished. The shed is 20m long running north to south with rubberised slats. The shed currently holds 98 fattening cattle on two sides, with a central feed passage and working doors at each end of the passage. The building is approximately 50 years old. A quick visual assessment indicated cobwebs, dust and a smell. The group went through the same discussion- deciding which of the 3 key elements weren t working correctly. I. Think of blue air and red air ACTION POINTS FOR AUCHENHEATH SLATTED SHED II. Create an outlet by opening the Yorkshire boarding and the doors III. Shift the drinkers to the passage way Kick the Cough, Charles Marwood, what causes pneumonia? Pasteurella RSV Mycoplasma PI 3 histophilis Bacterial infection, so can be treated Viral but there is a good vaccine Bacterial, common throughout most dairy farms in Scotland Viral, but there is a good vaccine Bacterial infection, so can be treated Because pneumonia is multi-factorial there are two approaches: Control/ Prevention (allies with Jamie s discussion in the morning) versus Treatment (fire fighting in an outbreak), usually too late to avoid losses.

5 Control 1 Pneumonia Reservoirs- reduce the impact of the reservoirs illustrated in diagram 1 Other cattle Mixing with other ages Control 2 Increasing immunity 1-Colostrum is the first defence- full of antibodies, water, fat, protein, minerals, vitamins & trace elements. Colostrum quality depends on the cow and her immune system but it can, and should, be measured. After 6 hours the calf stomach cells start to close up and larger proteins cannot be absorbed. Never assume the calf has sucked so administer colostrum as soon as possible. It is useful to get the calf sucking a teat as soon as possible in preference to a tube, as the sucking action draws the colostrum into the abomasum where it can be digested; tubed colostrum goes to the small rumen and is not directly digested. Atmosphere Moisture, air flow, air speed Neighbours Biosecurity Reservoirs House Temperature Environment Bedding, pens Equipment Teats, buckets Diagram 1, reservoirs of pneumonia risks - If the calf won t suck, tube 2litres at 2 hours old and repeat at 4 hours old. Any leftover colostrum can be frozen, particularly if it is good quality (use a colostrometer or send samples away for analysis). If in doubt calves can be tested before 7 days old for colostrum efficacy. 2-Calf Nutrition is within the control of the stockman. Managing the transition from monogastric to ruminant takes care. During the monogastric (milk) stage it is important to feed less more often, so aim for 3-4 feeds of 2litres per day. A calf needs 15% of their bodyweight to grow so measure birth weight and feed accordingly. If the target is kg at weaning then a calf will need to grow around 50kgs in 8 weeks 1.12kg per day. - Managing the transition from liquid to hard feeds will require around litres of water per day to replace the hydrating properties of milk and ensure sufficient hydration of the body cells. Scours at weaning is not necessarily a sign of infection, but subclinical acidosis which causes an inflamed rumen. If a calf is suffering from acidosis the white blood cells target the rumen and are not available to fight external disease threat, hence immunity drops and susceptibility to infection increases. 3-Other diseases Scour maintain hygiene, bedding and hydration (see above re acidosis) BVD be aware of herd status and PIs. Implement strict biosecurity and vaccinate. Crypto, Rotovirus, Navel ill can all be thwarted with good hygiene, isolation/biosecurity and swift diagnosis. 4-Vaccination There are many good vaccines available for BVD, Pasteurella, IBR, RSV, PI 3 and if testing shows there is a specific disease threat then don t be afraid to vaccinate. Prevention is often cheaper than treating an outbreak and factor in the cost of losses as well as veterinary costs. Know the status of your herd and vaccinate if necessary, relying on antibiotics leads to resistance and the spread of disease. 5-Viruses There are no antiviral veterinary medicines so a viral infection is difficult to treat. Generally anti-inflammatories such as Metacam and Finadyne are used, as these reduce pain and make the animal feel stronger so more bale to fight the infection. 6-Bacteria Antibiotics kill bacterial infections. Always treat early, isolate the animal in warm, dry conditions and complete the course. Antibiotics are very effective when used alongside anti-inflammatories, as in Resflor. Different brands have different clinical conditions so be aware of how fast acting, contra-indications, combined products, treatment period (Nuflor is 1 day, Hexasol is 6 days) and withdrawal dates. Avoid resistance by changing products regularly.

6 Further reading Better Returns Project (EBLEX) has useful material on pneumonia Housing Book (DairyCo) additional material available on housing that includes Jamie s calculations and recommendations The next Lanarkshire Monitor Farm community group meeting: Fertility Date: Tuesday 21 January Time: 10.30am for 10.45am start pm With John Cook & Charles Marwood Hot Lunch provided for those who RSVP Venue: Auchenheath Hall, Auchenheath Lanarkshire ML11 9XE Sophie Kinnear, DairyCo Facilitator Mobile: sophie.kinnear@dairyco.ahdb.org.uk Followed by: Managing grass for productivity Date: Tuesday 11 March Time: 10.30am for 10.45am start pm Lunch provided for those who RSVP Venue: Auchenheath Hall, Auchenheath Lanarkshire ML11 9XE