Keeping on top of youngstock health means taking several important measures, as Gemma Mackenzie reports.
A calf that suffers from serious illness will fail to perform to its full potential in later life, so keeping disease and parasites at bay is essential for getting the most from your youngstock.
And according to National Youngstock Association chairman Tim Potter, from Westpoint Vets, the key youngstock health concerns producers need to look out for are pneumonia and scours. He describes both of these as “multi-factorial” health problems that require arm-specific solutions.
Pneumonia can come from various sources – viruses, bacteria and mycoplasmas – but can also be caused by a poor environment, stress on the animal and poor immunity, says vet Harriet Fuller, from Marches Vet Group.
Although respiratory viruses may not actually cause severe disease on their own, they cause damage to an animal’s airway, letting in bacteria that then results in illness or death.
What’s more, Dr Potter says once a calf has suffered from pneumonia, its lungs never fully repair themselves, resulting in long-term damage to that animal.
“This is a disease we see throughout an animal’s life and is one of the biggest health concerns for calves in the early stages – it is very much a disease where prevention is better than cure,” he adds.
“It can impact on growth rates and make animals more susceptible to other diseases, so farmers need to identify the disease quickly when checking stock.”
He advises checking the temperature of any calves suspected of having pneumonia, as well as looking out for ones with coughs and snotty noses.
Both Dr Potter and Ms Fuller are keen to stress the link between stressors – disbudding, castration, weaning and fluctuations in temperature – and pneumonia.
In particular, grouping animals must be done with care, warns Ms Fuller: “Any stressful situation will reduce an animal’s immunity and predispose it to illness and disease. And mixing animals is very stressful, so if you are buying in stock, try to buy a group all at once rather than buying a few at a time and adding to a group.”
They recommend the following measures to keeping pneumonia at bay:
• Ensure buildings are well ventilated with minimal humidity (for more information on housing, see Farmers Weekly’s youngstock housing feature in 2 December issue)
• Avoid stressors or “periods of challenge” on the animals
• Ensure calves get the right amount of colostrum in the first 24 hours after birth – this can be backed up by a blood test in the first 10 days
• Avoid grouping animals of different age groups and from different sources, where possible
• Keep an eye out for other diseases that can trigger pneumonia, such as BVD and lungworm; this is particularly relevant in animals that have been brought inside from outdoor grazing.
Another big health concern in youngstock is scours – a multifactorial illness that can be caused by viruses, bacteria and parasites, explains Dr Potter.
“Although there are different causes, fortunately the treatment is pretty much the same. And often we can reduce a lot of this risk through good colostrum management, and by vaccinating the dam against viruses prior to calving,” he explains.
“Dirty calving sheds and equipment are a source of this problem. Producers really need to go back to basics with hygiene if they want to get on top of scours.”
He recommends the following hygiene measures to keep scours under control:
• Make sure all feeding equipment is kept clean, paying particular attention to sick calves by feeding them first and cleaning the equipment before feeding other stock
• Ensure the calf pens are clean, and make sure to properly muck out, disinfect and allow to dry, before bringing a new group into a pen
• If using a feeding tube for feeding colostrum and one for feeding sick calves, make sure they are labelled clearly to avoid feeding newborn calves with equipment infected by sick calves
• When moving from different pens of calves, make sure to wipe or clean your boots.
“If a farmer discovers scours in their youngstock, they need to work hard to replace the fluids lost in the calves and minimise the spread – this could involve isolating a sick calf from the rest of the group,” adds Dr Potter.
“Prevention is all down to practical measures like minimising the spread between groups, and making sure to clean your boots when you move from one group to another.”
There are a wide range of vaccines available on the market for scours and pneumonia, but, as Ms Fuller warns, these are not a “magic bullet” against disease, and they should only be used in conjunction with other measures as part of a farm’s overall health strategy.
Dr Potter adds: “Vaccines need to be used in combination with other measures; you cannot put a calf in a horrendous environment and expect it to do well just because you have vaccinated it.”
Furthermore, he says, when faced with disease outbreak, farmers should get diagnostics done to correctly identify what vaccines are needed to tackle the problem.
He adds: “When you come to putting the vaccines into the animals, you need to make sure they are given prior to any period of challenge such as disbudding or castration.
“People also need to be more careful about how they handle vaccines; they are quite delicate in their nature so they need to be kept in controlled conditions. And producers need to make sure they are being given to the animals immediately after they have been prepared, because often once they are made up they will deteriorate very rapidly.”
Producers keeping youngstock should create a health plan in partnership with their vet and nutritionist, says Dr Potter.
“There’s a lot of talk about the impact of health planning, and I think that certainly when looking after youngstock. It’s a great way to agree with the people involved what is going to happen with the calves.
“You need to be ready to investigate the causes, if a disease outbreak occurs. And lots of protocols need to be decided beforehand about how you are going to manage the problem, alongside recommendations for how to change the management, should a problem occur.”
In addition, he recommends keeping up-to-date records of youngstock disease instances and mortality.
“It’s useful to have a snapshot of what’s going on with the calves so you can identify when you need to do something about a disease outbreak. It also comes in handy when you come to review your system.”
Case study: Steven Bland, Abbott Lodge, Clifton, Penrith
Youngstock are often the forgotten group, particularly when undergoing herd expansion, says Steven Bland of Abbott Lodge, Clifton, Penrith.
Speaking from experience – having increased cow numbers from 120 to 300 over 10 years – Mr Bland explains how calf housing had been the limiting factor to calf performance as stocking rates had increased.
“Calves were doing poorly – poor ventilation meant bedding was damp and pneumonia was a big problem. Whatever we did, we couldn’t get on top of the problem.”
In fact, Mr Bland recalls a time when batches of 35 calves were having to be jabbed for pneumonia.
“Drainage was poor and we couldn’t get the calf through-put or clean out pens quick enough,” he says.
However, since installing a brand new calf building, designed to maximise youngstock health, pneumonia has become a thing of the past and overall calf mortality rate (of those born alive) is 2%.
“Having visited other farms, we decided to build the calf housing in isolation from other buildings,” explains Mr Bland. “Experience showed buildings with shared air spaces performed badly in terms of calf health.”
The whole building was designed for optimum ventilation, with panels up to 1.2m high and then vented metal cladding on the south-east and north sides of the shed. This allows air in, but keeps the elements out.
An insulated roof also keeps the shed warm in winter, but cool in the summer. A raised ridge that is designed to prevent rain from coming in has also been installed.
Calves are kept in individual pens up to two weeks of age and then moved on to automated milk feeders.
“In the old shed, we only had room for one group on one automated machine – this meant there was no break between groups and a big age difference within a group.”
Now, the system is set up with two machines in two pens, each housing up to 25 calves. Mr Bland says: “We have always been religious with steam cleaning the individual pens, but in the old system, we couldn’t follow this through with the group pens – now we can.
“Calves are your future stock – farmers commonly look at investing in a shiny, new tractor, but instead we should be looking at investing in calf buildings.”
He also stresses the need to establish individual farm targets. “Our aim is to rear every calf born alive. Good staff is also really crucial – when staff are keen, let them make the decisions and be proactive.”
Mr Bland’s top tips for maximising calf health
• It’s worth housing calves in a separate air space to other stock – don’t just tack on new buildings to existing sheds for convenience
• Ventilation is key
• Design a simple system that is ‘human proof’
• Automatic calf feeding systems are not an excuse for poor management – always visually observe calves and monitor performance
• Visit other farms to get an idea of the best set-ups
• Ensure breaks between groups and steam clean between batches
• Put coats on smaller, young calves up to two weeks of age in winter
• Good colostrum management
• Provide water and course mix from a young age, as well as quality barley straw.
Case study: Anthea Kitching, Crathorne Farms, Yarm, Yorkshire
Don’t wait to the afternoon to treat a calf if you notice a problem in the morning, advises calf rearer, Anthea Kitching.
“Act now rather than later on,” she says. “Take the calf’s temperature, treat accordingly and if a calf isn’t drinking in the morning don’t wait until the second feed to get them drinking – once they’re down, they’re hard to get back up.”
Ms Kitching rears 400 dairy calves a year from an autumn block calving system at Crathorne Farms, Yarm, North Yorkshire. “I’m a strong believer in always using pain relief when a calf is ill. If you don’t use an antibiotic, rehydrate them and use pain relief, you are fighting a losing battle.”
She also stresses the need to be observant at every feeding and make sure every calf has drunk. “We’ve got new feeders with individual compartments and it’s marked how drinking speed varies between calves. I would definitely recommend this set up to tracking intakes.”
Housing calves in a dry, clean environment was also crucial, she said. “Hair in the nose is a calf’s first line of defence against bacteria. When a calf is lying in a damp environment, ammonia will burn the hair and increase the likelihood of infection.”
By installing igloos on the edge of an open sides shed at Crathorne Farms, ventilation has been greatly improved and no coughing has been seen this season.