Glässer's Disease: lateral recumbency
The bacterium is ubiquitous, found throughout the world and is present even in high health herds.
Glässer’s Disease
Glässers Disease is caused by Haemophilus parasuis . H. parasuis is endemic in the majority of pig herds and is frequently isolated from the nasal cavities of healthy pigs.
Introduction of H. parasuis in a naïve herd, (mixing pigs of different origins), may lead to high rates of morbidity and mortality. Introduction of naïve pigs into a H. parasuis contaminated environment, (mixing pigs of different origins), may cause severe economic loss.
Etiology
Haemophilus parasuis
is a very small bacterium. At least fifteen different serotypes have been identified.
The bacterium is ubiquitous, found throughout the world and is present even in high health herds. It is often associated with stress, especially during transport of pigs. In naïve populations the bacterium may cause severe disease on its own. It can also be the cause of secondary bacterial infections in other diseases, particularly enzootic pneumonia (M. hyopneumoniae ).
Clinical signs
In the majority
of H. parasuis endemic herds, piglets usually have a strong maternal immunity until 6 to 10 weeks
of age. As a result, the effects of infection in weaners are usually minimal. If however maternal immunity
wears off before infection piglets may develop severe disease. Outbreaks of disease are sometimes experienced
in sucking pigs, particularly in gilt herds.
Acute disease
Pigs with Glässers disease become rapidly depressed,
have a high temperature, stop eating and are reluctant to rise. H. parasuis attacks
joint surfaces and the smooth membranes around the intestines, lungs, heart and brain. In young
growing pigs meningitis or middle ear infections are common together with pneumonia, pericarditis,
peritonitis and pleurisy.
H. parasuis also causes individual cases of arthritis and lameness with acute pain, fever and inappetence. It is spread via the respiratory tract and a characteristic feature is a short cough of only 2-3 episodes. Sudden death in healthy sucking piglets is not uncommon in herds with a problem particulary when immunity in gilt litters is low.
Chronic disease
Sucking piglets are often pale and poor doers 10-15%
of the piglets may be affected in each litter. Such pigs then continue into the growing period
with poor growth. If chronic pericarditis is caused, sudden deaths occur.
Diagnosis
A diagnosis of Glässers
disease is confirmed by:
- Clinical signs
- Post-mortem examination
- Isolation of the organism
Conclusive diagnosis can however be very difficult as H. parasuis is difficult to culture, post mortem is seldom conclusive, and the organism can easily be missed in bacteriological examinations.
Differential diagnoses
- Actinobacillus suis
- Actinobacillus pleuropneumoniae
- Mulberry heart disease
- Streptococcal meningitis
- Streptococcal septicaemias
Treatment and Prevention
Ideally, antibiotic treatment should begin before clinical disease is apparent, which requires frequent inspection
of any pigs at risk.
H. parasuis has a wide antibiotic sensitivity including amoxycillin, ampicillin, OTC, sulphonamides, penicillin and ceftiofur.
Management control and prevention
- The lactating and creep rations can be medicated with antibiotics
- Vaccination with inactivated vaccines based on Haemophilus parasuis serotypes. See Vaccines