A move towards earlier in life vaccination of young calves against viral pneumonia is helping the University of Edinburgh’s Langhill Farm based in Roslin, Midlothian mitigate the impact of the disease and rear healthier heifer replacements for its milking herd.

With 240 Holstein Friesian milking cows, all replacements are homebred and reared on farm. Herd health is overseen by vet Paul Wood, principal farm clinician at the Royal (Dick) School of Veterinary Studies R(D)SVS who says the youngstock rearing operation’s immunity-led calf pneumonia management plan has taken a significant step forward in recent years.

“Over the last three years, implementation of a sound colostrum feeding protocol and vaccination of the calves against pneumonia has certainly helped keep this particular disease issue under control. Vaccination has made a significant difference and apart from the odd calf still needing sporadic treatment, we have hardly seen any disease signs in the youngstock,” says Mr Wood.

The adult dairy herd has used more sexed semen over the last four or five years to boost the heifer count because they require 80-100 female herd replacements to be reared each year. The youngstock rearing operation is supervised by Wilson Lee.

“The herd calves in a winter block between September and March. We ensure all newborn calves receive plenty of high quality colostrum via two feeds during the first 24 hours of life.

"Calves are kept near their mothers for five days in small groups of about seven calves, before moving into our calf rearing shed and kept in penned batches of 20-25 animals until weaning at eight weeks of age. The calves are reared on milk replacer using computerised feeders. We have one feeder that can rear up to 60 calves and another that can manage 30 calves,” explains Mr Lee.

After weaning the calves move on to what Wilson calls ‘primary school’ – another shed where they are fed concentrates and straw until six months of age. From there they move into ‘high school’ at which stage they are fed silage, meal and straw until 12 months of age. Mature youngstock are grazed over the summer months, bulled at 15 months of age and calve down at a 24-month-old target.

When it comes to herd health management, Wilson says the Langhill dairy farm team relies heavily on the input of Paul Wood and his veterinary-qualified colleagues based at the R(D)SVS.

“We are fortunate to have access to some of the best veterinary brains in the country, so it would be foolhardy not to use them,” he says.

One of the key interventions has been vaccination of young calves against pneumonia. Over the last three years, this has been done at between two and three weeks of age.

“These heifer replacements are very valuable animals,” says Mr Wood. “We are using more sexed semen to boost the number of heifer calves, but our female and male calves do still mix. Pneumonia is a real threat because of this and various other environmental risk factors, as it is on any rearing unit.

“We also know that pneumonia in early life leaves significant lung damage, which means that growth and subsequent milking performance as an adult can be compromised, even in those calves that apparently recover from a pneumonia infection. That’s why vaccination against this disease has become very important.”

Paul Wood is an advocate of intranasal pneumonia vaccines. “We’ve seen good responses on farms following the use of these type of vaccines. Onset of immunity is quicker than with injectable vaccines and that is important in terms of protecting vulnerable young calves,” he says.

“We see so many older cattle with chronic lung damage that it makes sense to protect heifer calves at as young an age as possible. Early life vaccination against pneumonia is important for growing beef animals too, so that growth rates are not adversely impacted.”

Mr Wood adds that just as any immunity gained from colostrum wanes, many calves often start facing a potential disease challenge – typically when they move from individual pens into group housing.

“There are many early stresses for these young calves, so it makes sense to boost their immunity early,” he said.

Last winter, Mr Wood recommended that the youngstock rearing unit started vaccinating calves with the new Bovilis INtranasal RSP Live pneumonia vaccine. “It’s a new vaccine that can be used in calves as young as a week of age and, on reviewing the datasheet, we noted that no other vaccine protects calves earlier or faster. Immunity to BRSV and Pi3 is gained just 5-7 days after application and this lasts for 12 weeks,” he says.

So far so good though. Calves born between December and March have performed very well and in the main have been free from disease.

“We will assess their growth performance through the year and certainly don’t expect to lose any or see any knock-backs as a result of viral pneumonia,” Wilson says.

The team used the new vaccine for the first time last December. “We kept the protocol the same and administered it to 2-3 week old calves, but Paul has suggested we take advantage of its opportunity for earlier use during the 2020 calving season later this year.

“We plan to vaccinate the calves at a week to 10 days of age prior to moving them into the group housing. This makes sense because the stress of moving them and the fact they are likely to encounter a higher pathogen load when in a group housed situation, is a significant risk,” added Wilson.