Difference between revisions of "Enzootic Pneumonia - Calves"
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==Signalment== | ==Signalment== | ||
| − | Mainly a problem in calves less than 6 months old and particularly affects 2-10 week old animals. It occurs more commonly in dairy calves than beef calves. | + | Mainly a problem in calves less than 6 months old and particularly affects 2-10 week old animals. It occurs more commonly in dairy calves than beef calves. |
==Diagnosis== | ==Diagnosis== | ||
| − | + | Acutely affected animals: | |
| + | Affects a group of calves. Respiratory signs are present and the animals are dull. To establish the cause nasopharangeal swabs or broncho-alveolar lavage can be undertaken and examined for bacteria, viruses or mycoplasma. | ||
==History and Clinical signs== | ==History and Clinical signs== | ||
Causes unthriftiness in animals < 6 months old | Causes unthriftiness in animals < 6 months old | ||
Revision as of 23:34, 27 July 2010
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This article is still under construction. |
Description
A pneumonic disease which is caused by a range of infectious agents in combination with management and environmental stress causing damage to the respiratory tract. It is principally of viral origin including
- Bovine respiratory syncytial virus (BRSV)
- Parainfluenza- 3 (PI3)
- Bovine viral diarrhoea virus (BVDV)
- Adenoviruses
- Calf coronavirus
- Bovine herpes viruses
Mycoplasmas hve also been implemented and secondary bacterial infection commonly Bacterial agents include
- Manheimia (Pasteurella) haemolytica serotype A1
- Pasteurella multocida
- Arcanobacter pyogenes
- Haemophilus somnus
All agents are transmitted by aerosol and direct contact.
Signalment
Mainly a problem in calves less than 6 months old and particularly affects 2-10 week old animals. It occurs more commonly in dairy calves than beef calves.
Diagnosis
Acutely affected animals: Affects a group of calves. Respiratory signs are present and the animals are dull. To establish the cause nasopharangeal swabs or broncho-alveolar lavage can be undertaken and examined for bacteria, viruses or mycoplasma.
History and Clinical signs
Causes unthriftiness in animals < 6 months old
All transmitted by aerosol and direct contact
Pathology
Gross pathology
Consolidation of the cranioventral lung areas which increases in volume with duration. Exudate is present in the main airway of affected lobules with thickening of the surrounding connective tissue
Micro pathology
Even to proper follicle formation, some of which may be large enough to compress the lumen. A Mixed cell exudate will be present in the airway lumen and substantial lymphoid tissue will be present around the airways. The alveolar walls may be thickened with lymphocytes.
Treatment and Control
Once a diagnosis has been made as to the likely causative organisms a number of management issues on the farm must be addessed. These include ensuring each calf ingests enough good quality colostrum, good nutrition, stress management, good housing, and other management of any concurrent diseases. Additionally group sizes should be assessed and ideally no more than 20 calves per group. Animals shoul be kept in groups of the same age and should not share airspace with adult cattle. If this is not possible animals should be arranged with the air flowing from youngest to oldest. Isolation/ hospital pens should be available to prevent spread of disease and to ensure affeced animals are cared for correctly. Additionally once causative organisms have been identified vaccination programmes can also be put in place for cows 4 weeks pre-partum to improve colostral antibodies that the calves will recieve.