Any farmer who buys or sells weanlings will be well aware of the detrimental effect a case of pneumonia can have on livestock.
That is why many farmers take no chances when buying weanlings and opt to vaccinate stock as soon as possible following arrival on the farm.
To ensure a weanling remains healthy and pneumonia free, farmers should aim to minimise the animal’s exposure to disease and maximise the weanlings defence against disease.
Minimising exposure to pneumonia
Minimising a calf’s exposure to disease may be achieved through strategies such as the use of a closed herd, screened replacements and positive-herd immunity.
Good housing conditions with particular attention given to adequate ventilation and shed space, plays a key role in preventing respiratory disease in cattle.
An outbreak of pneumonia in a group of weanlings is considered to be closely associated with situations where the animal’s immune system is compromised.
This can occur as a result of stress associated with weaning and therefore stress should be minimised at weaning.
Nutrient deficiency can significantly suppress the immune system, resulting in a poor response to vaccination as well as resulting in calves becoming unable to fight off infections.
Alternatively, adequate nutrition minimises long-term negative effects of disease and permits a more rapid recovery.
A disease prevention programme for pneumonia usually involves vaccination on most farms.
Vaccines
Viral specific vaccines are available but their effectiveness is dependent on management procedures and the timing of administration, according to Animal Health Ireland (AHI).
Depending on the causative agent (virus) and product, the vaccine should be administered prior to weaning, bearing in mind that some products require a booster dose.
Where possible, do not mix calves from different sources until after the vaccinations have had time to produce immunity (2-3 weeks).
According to AHI, it is vital – irrespective of the programme – that vaccines are stored and administered as per manufacturer’s instructions, including being given at the right time, at the right dose and route of administration and right interval between primary and booster (if required).
It is also very important that vaccines are not given to sick calves as sick, or stressed calves will not respond appropriately to the vaccine.
The advice is to work in close association with a veterinary practitioner. Collection of nasal mucous samples or swabs for laboratory diagnosis will direct the selection of the appropriate vaccine and/or antibiotic treatment.