Plan now to protect calves and youngstock
A paper published earlier this year reported that Mannheimia haemolytica (formerly known as
Pasteurella) was found in 90% of lung samples taken from calves suffering from pneumonia.
But what does this mean, and is it important?
Bacteria from the pasteurella family are commonly diagnosed in pneumonia outbreaks and
one of this group, M. haemolytica, is known to be able to cause severe disease in younger
animals. Most calves and adult cattle carry the bacteria in their respiratory tracts, and it is
only when they are stressed that they succumb to infection. Stress can be caused by moving
or mixing groups, and the bacteria is often joined by a virus capable of causing pneumonia
which, potentially makes for a very severe outbreak.
Two common viruses that can cause pneumonia are PI3 and RSV. A young animal with a
temperature of between 103-105OF and very noisy lungs – almost asthmatic-sounding – may
be ill with RSV. In comparison, PI3 is a milder syndrome without the lung noises.
An older animal with a temperature as high as 107OF and noisy breathing could be suffering
from IBR. However, reaching a definite diagnosis is rarely as simple as this. In reality, most
pneumonia is due to a mixed infection of viruses and a bacterial infection.
Antibiotic therapy is only effective against the bacteria involved in pneumonia, so to prevent
future outbreaks vaccination should be considered. Bovipast® RSP induces immunity against
RSV, PI3 and M. haemolytica - the three main causal agents of pneumonia, particularly in
younger animals.
In addition to the initial course, calves should receive a Bovipast RSP booster any time up to
a year later. This should be given at least two weeks prior to any period of risk (eg housing,
transportation, or mixing age groups), as it helps build up their immune response and combat
infection.
A study proved that a single booster of Bovipast RSP (the only combined bacterial and viral
pneumonia vaccine on the market) at three, six or 12 months after the initial vaccination,
produces the same antibody response, to the viral components, as that induced by the initial
course.
Ideally, boosters should be given at least two weeks before the risk as it allows the body to
build up its response and gives the animal full protection. As the study proved that boosters
given at different time intervals show no reduction in antibody response, it means that herds
with different calving patterns or buying-in policies can time injections to suit management
systems.
An outbreak of pneumonia can mean that replacement heifers will not reach target bulling or
calving weights which in turn affects lifetime yield. Beef animals, meanwhile, need to be
growing at 0.7-0.9kg/day, but calves affected by pneumonia will fail to achieve this because
they have lung damage. Protecting animals with Bovipast RSP while they are baby calves,
and ensuring that they receive their booster at the best time, will minimise the threat of
pneumonia caused by the most common bacteria and viruses.
Contact the practice to discuss your unit’s pneumonia risk level and disease management.