For beef farmer Kevin Sparke, keeping a good weight for age is a high-priority and he is well aware the main threat to achieving this is pneumonia.
Mr Sparke, a fourth-generation farmer, runs 180 suckler cows and 700 ewes on 397 upland hectares (980 acres) at Little Swinburne Farm, Hexham. The cows are Limousin or British Blue crosses with some dairy genetics in the background, bred respectively to Blue and Limousin sires.
A first batch of 60 calve in February, the rest in May. The best February-born females are kept as herd replacements, with the remainder of the group sold either just weaned in November or as yearling stores the following February.
Calves from the May batch are all housed for their first winter, then the best are sold in March and the remainder go in May and August. Among March sales in particular, Mr Sparke is striving for show-winning quality with good length, clean lines, sound legs and feet, and good head width.
At about 300 metres (1,000ft) above sea level on an exposed location, the winter climate brings wild fluctuations, in particular between maximum and minimum daily temperatures, wind speed and direction.
Early January is a predictable risk period for calf pneumonia, triggered by frequent daily temperature swings of 10-15degC, coupled with high humidity.
As the 2014-15 housing period began, calves he considered to be most at risk were given a single-dose intranasal vaccine against two of the most common respiratory viruses – para-influenza 3 virus (Pi3v) and bovine respiratory syncytial virus (BRSv).
Calves which were assumed to be most vulnerable, and therefore selected for vaccination, were smaller and later born. Less than three months later, some classic signs of respiratory disease were observed.
Under advice from David Parkins, Intake Veterinary Services, antibiotic treatment was administered to affected calves, all of which, without exception, were those which had not been vaccinated. Despite being in close proximity, Mr Sparke says none of the vaccinated calves required treatment.
He says: “Our assumption smaller animals were more vulnerable was clearly a mistake. In addition to medicine costs and extra work involved in handling and treating calves, affected animals stopped growing for four to six weeks. When you are still paying out for feed but they are not putting on live weight, it is seriously bad news for margins.”
Following conversations with Mr Parkins a new pneumonia protection policy was created. Calves born indoors in February get an intranasal vaccine licensed for use from nine days of age with three months’ duration of immunity against Pi3v and BRSv pneumonia pathogens. Those born at grass in May and any of the February group being overwintered then get the same single-dose vaccine pre-housing.
Mr Parkins says the justification for pneumonia vaccination is more about performance gain to ensure calves have the best opportunity to hit target growth rates, rather than just disease protection.
All his clients which have a history of poor calf respiratory health are advised to adopt a comprehensive, best practice health plan. This involves ensuring all calves get enough colostrum within six hours of birth, well ventilated housing with dry bedding and vaccine protection.
For the Sparke family, gains made through improved respiratory health are critical to the beef herd’s success. Whether selling potential show-winning calves, or high quality store cattle, the aim is to do so when maximum margin can be realised between each animal’s value and the costs incurred to date.
Mr Sparke says: “We cannot afford standstills. Margins are difficult to achieve, so we need to protect them by eliminating mistakes, in particular by avoiding wrong assumptions. To our cost, we have proved there is no link between bigger size and lesser disease risk.
“The reality, of course, is bigger animals are worth more. So financially, they are a greater risk the longer you keep them.”