Pneumonia and scours are the two main problems in calves that vet advice is asked for. Often these diseases occur in severe outbreaks where calves can be lost if not treated appropriately and quickly, but these can be prevented avoiding stress, production losses and saving you money on vet bills!
Pneumonia
There are several causes of pneumonia (Table 1), most commonly viruses cause some lung damage before secondary bacteria colonise creating further damage. This secondary damage causes clinical signs and often can be so extensive that it becomes permanent.
Table 1: Common Pneumonia-causing pathogens
Clinical signs
Often we see calves needing abdominal effort to breathe, by this time treatment is both expensive and too late, as permanent and irreversible lung damage has already occurred. Cows have a high oxygen requirement, but comparatively small lungs compared to other animals, consequently, any lung damage seriously affects that animal for the rest of its life, reducing its productivity, longevity and profit.
Treatment
Many find the Wisconsin calf respiratory scoring system a useful method to monitor signs and treat early, as this reduces the amount of lung damage. While antibiotics are often needed anti-inflammatories are key in treating pneumonia and are highly effective when given early.
Prevention
As always, prevention is better than cure! There are calf pneumonia vaccines given intranasally from 10 days old. These are highly effective, however, it is important to understand the pathogens causing your calf pneumonia before using them. This can be done simply by blood sampling, post mortems or broncho-alveolar lavage in live calves; so speak to your vet.
Ventilation is also really important in preventing pneumonia. Ensuring appropriate air changes for the calves and not mixing animals of different ages in the same air space is crucial.
Scours
There are several pathogens that cause scours in very young calves including; rotavirus, coronavirus, E. coli and cryptosporidium. It is important to remember that diarrhoea is not the cause of death in scour cases, dehydration is the killer. Consequently looking at how sunken the eyeballs are is an important measure of hydration and influences the treatment decisions.
Treatment
Contrary to many people’s beliefs, milk should not be withdrawn in scour cases. Scouring calves are not only needing energy and nutrients to grow, they are losing large amounts of water through the scour. Milk is essential to provide the energy and nutrients for life and so normal milk feeds should be continued during treatment. These milk feeds should be supplemented with electrolytes in water, which often needs to be stomach tubed. A scouring calf which appears bright often needs at least 4L of water as well as two 2L milk feeds.
If oral rehydration can be started early enough in the disease process, veterinary intervention, such as dripping calves, can often be avoided.
Prevention
Colostrum and cleanliness are key to preventing early calf scours. As calves are born with no immunity, they need to absorb Igs in their first 24 hours of life. Colostrum can be boosted by vaccinating cows for rotavirus, coronavirus and E. coli but calves still need to be given 4L within two hours of birth for optimal immunity transfer. Cryptosporidium can only be combatted with cleanliness. It is important to remember that not all disinfectants kill cryptosporidium, so if this is an issue on your farm ensure you are using the correct product.
Scour kits are quick and easy tests to understand what pathogens are on your farm, so any outbreaks of scour should be tested immediately. Often this will not change treatment choices but may alter your management practices to prevent scours on your farm in the future.
Pneumonia
There are several causes of pneumonia (Table 1), most commonly viruses cause some lung damage before secondary bacteria colonise creating further damage. This secondary damage causes clinical signs and often can be so extensive that it becomes permanent.
Table 1: Common Pneumonia-causing pathogens
| Viruses | Secondary Bacteria |
| Parainfluenza III (PI3) | Mannhaeimia spp. |
| Respiratory syncytical virus (RSV) | Pasturella multocida |
| Infectious bovine rhinotracheitis (IBR) | Histophilun somnus |
Clinical signs
Often we see calves needing abdominal effort to breathe, by this time treatment is both expensive and too late, as permanent and irreversible lung damage has already occurred. Cows have a high oxygen requirement, but comparatively small lungs compared to other animals, consequently, any lung damage seriously affects that animal for the rest of its life, reducing its productivity, longevity and profit.
Treatment
Many find the Wisconsin calf respiratory scoring system a useful method to monitor signs and treat early, as this reduces the amount of lung damage. While antibiotics are often needed anti-inflammatories are key in treating pneumonia and are highly effective when given early.
Prevention
As always, prevention is better than cure! There are calf pneumonia vaccines given intranasally from 10 days old. These are highly effective, however, it is important to understand the pathogens causing your calf pneumonia before using them. This can be done simply by blood sampling, post mortems or broncho-alveolar lavage in live calves; so speak to your vet.
Ventilation is also really important in preventing pneumonia. Ensuring appropriate air changes for the calves and not mixing animals of different ages in the same air space is crucial.
Scours
There are several pathogens that cause scours in very young calves including; rotavirus, coronavirus, E. coli and cryptosporidium. It is important to remember that diarrhoea is not the cause of death in scour cases, dehydration is the killer. Consequently looking at how sunken the eyeballs are is an important measure of hydration and influences the treatment decisions.
Treatment
Contrary to many people’s beliefs, milk should not be withdrawn in scour cases. Scouring calves are not only needing energy and nutrients to grow, they are losing large amounts of water through the scour. Milk is essential to provide the energy and nutrients for life and so normal milk feeds should be continued during treatment. These milk feeds should be supplemented with electrolytes in water, which often needs to be stomach tubed. A scouring calf which appears bright often needs at least 4L of water as well as two 2L milk feeds.
If oral rehydration can be started early enough in the disease process, veterinary intervention, such as dripping calves, can often be avoided.
Prevention
Colostrum and cleanliness are key to preventing early calf scours. As calves are born with no immunity, they need to absorb Igs in their first 24 hours of life. Colostrum can be boosted by vaccinating cows for rotavirus, coronavirus and E. coli but calves still need to be given 4L within two hours of birth for optimal immunity transfer. Cryptosporidium can only be combatted with cleanliness. It is important to remember that not all disinfectants kill cryptosporidium, so if this is an issue on your farm ensure you are using the correct product.
Scour kits are quick and easy tests to understand what pathogens are on your farm, so any outbreaks of scour should be tested immediately. Often this will not change treatment choices but may alter your management practices to prevent scours on your farm in the future.