This document summarizes enzootic pneumonia in sheep, also known as sheep pneumonia. It is an acute respiratory disease affecting sheep of all ages, caused by a combination of environmental and infectious factors. Viruses damage the respiratory tract lining, allowing bacterial invasion by pathogens like Pasteurella haemolytica. Environmental stressors like overcrowding and weather changes predispose sheep to infection. Clinical signs include fever, nasal discharge, coughing and respiratory distress. Diagnosis involves isolating P. haemolytica from samples. Treatment includes long-acting tetracyclines and sulfonamides. Prevention focuses on minimizing stress and maintaining good sanitation.
1. DISEASES OF RESPIRATORY SYSTEM
Enzootic pneumonia in sheep
, shipping fever,Pasteurellosis
hemorrhagic Septicemia
ovine pneumonia
Prof Dr Mohamed Ghanem
Prof of Veterinary Internal Medicine
Head Animal Medicine Department
2. Definition
• An acute type of pneumonia caused by mixed
environmental and infectious factors affecting
sheep of all ages with high prevalence in nursing
and feedlot lambs,
• characterized clinically by signs of respiratory
distress, mucopurulent often blood tinged
oculonasal discharge, depression, anorexia and
pyrexia and pathologically by pneumonitis and
pleuritis.
3. Etiology and pathogenesis
Microorganisms
(viruses and
bacteria)
environmental
factors
producing
stress
working synergistically to
damage the cells lining the
respiratory tract
allowing invasion of other
organisms
4. Environmental factors predispose for infection include:-I
1- Extensive management systems
• Overcrowdness: Close contact allowing for easy
transmission of infective agents.
• A build up of potential pathogens in the
environment due to bad hygiene.
• The production of noxious gases as ammonia,
H2S and CO2 which irritate or damage the
respiratory mucosa or alter the phagocytic
properties of macrophages.
• Small dust particles from dry feedlot carry
pathogens deep into the respiratory tract.
6. 2-Climatic conditions play a role as
-seasonal variations in the incidence
of the disease.
-The peak incidence occurs at
shearing, lambing, change of diet and
with unsuitable weather.
3- transportation predispose for infection.
7. Infectious causes-II
1- Most respiratory viruses including
parainfluenza virus type 3,
respiratory syncytial virus,
adenoviruses and reoviruses
Causing damage the lining epithelium thus destroying
ciliary action and mucous protection allowing
bacteria to colonize on these damaged areas.
Beside damage of the epithelial cells, viral infections
suppress the function of bronchoalveolar
macrophages.
8. • 2- Pasteurella haemolytica (Mannheimia
haemolytica)
• a common inhabitant of the nasopharyngeal mucosa
of normal animals
• multiply, produce toxins (leukotoxins) and invade
mucosa causing further damage.
• Pasteurella haemolytica proliferation with a cytotoxic
virulence factor can destroy alveolar macrophages.
9. • 3- Stress factors elevates ---- the serum cortisol
levels with a resultant
• immunosupresssion,
• a decrease in lymphocyte
• a decrease in circulating leucocytes.
10. • 5- The bronchoalveolar macrophage activity is
the major means of particle clearance from
alveolar areas of the lung.
11. • The disease begins with acute
rhinitis and pharyngitis and from
this nidus, infection descends to
lower respiratory tract.
12. Clinical signs
1. Fever 41-42oC, drooping ears and lowering head,
2. the sick lambs refuse to eat and loses live weight.
3. Mucopurulent nasal discharge and Lacrimation.
4. Respiratory rates are accelerated, difficult and often
accompanied by coughing.
5. Weakened lambs isolate from the flock.
6. Auscultation of thorax reveals consolidation of the
anterioventral parts of lungs.
7. Morbidity reaches 50%, while mortality reaches
10%.
14. Diagnosis
1. Case history and signs.
2. Isolation and identification of pasteurella
haemolytica.
3. At necropsy, finding of consolidation in the
lung accompanied by pleuritis and
pericarditis.
15. Treatment
• Long acting tetracyclines and sulfonamides are
preferable for 3 days (with other treatment line).
• New drugs:
• Del-phicol: (florfenicol): 3 ml/ 45kg IM repeated after 2
days (other name: nuflor)
• Draxxin: (tulathromycin): 1 ml/40 kg SC only once
• Enro: (enrofloxacin): 1 ml/40 kg BW SC or IM for 3
days
• Colitrim (sulphaiazine + trimethoprim): 1 ml/15 KG BW
IM repeated after 2 days
16.
17.
18.
19. Prevention
• Avoid stress factors as management practices to
minimize the stress of transportation and
adaptation of the lamb to its new environment.
• Ensure that the sanitary measurements including
feed and watering facilities are always good.
• Avoid introduction of lambs from various
sources.
• Immunization against primary and secondary
causes.