This document discusses bovine respiratory disease (BRD) in calves, which is caused by various viruses and bacteria. It can cause pneumonia of varying severity. Common viral causes include respiratory syncytial virus, parainfluenza 3, and bovine viral diarrhea virus. Bacterial pathogens like Mannheimia haemolytica may cause secondary infections. Calves aged 2-5 months are most susceptible. Clinical signs include cough, nasal discharge, fever and respiratory distress. Diagnosis involves virus isolation, serology and histopathology. Treatment consists of antibiotics and supportive care. Vaccination helps control the spread of BRD.

2. 📌Definition
• it is multifactorial respiratory
disease of calves caused by
different types of virus and
characterized by variable
degree of severity of
pneumonia.

3. 📌 Etiology
• virus agents:-
• respiratory syncytial virus, parainfluenza 3, Reovirus,
Rhinovirus, Adenovirus, BVDv and Herpes virus.
• Bacterial agents:- Pneumonia of calve may be
complicated with secondary bacterial infections such as
Chlamydia sp, Mycoplasma sp, Mannheimia haemolytica,
Streptococcus pneumonia, Corynebacteria bovis and
E.coli .
• Environmental factors:-
• The disease is often associated with low environmental
temperatures and a high humidity It is thought that the cold
may allow infection to flare up partly by affecting the
respiratory defence. Housing of calves in close pox help in
transfer of infection.

4. 📌 Epidemiology
. stribution: widely spread and present in Egypt.
. Animal susceptibility: The disease is most common in
young calve of 2-5 M of age and young cattle.
• Seasonal incidence: winter months with bad
management in calve housing.
• Mode of transmission:
• The source of infection is nasal discharge of clinical
infected animal and the infection can be transmitted
through inhalation of aerosol infection.

5. 📌Clinical signs
 IP is varies and morbidity rate reach 100% while the
mortality rate is less than 30%.
• Acute form:
• Several animals will usually become sick within the
next 24–48 hours. There is normally a reduction in feed
intake of the group and widespread coughing will be
apparent.
• a mucoid or mucopurulent oculo-nasal discharge,
tachypnoea (respirations are usually over 40 per
minute), dyspnoea and hyperpnoea are normally
present .

6. .Chronic form:
•The condition is one of gradual
onset. It may have a slight mucoid or
mucopurulent oculonasal discharge.
The temperature is normal or slightly
raised at 38.5–39.5 C. There is a dry,
explosive cough that is usually
produced singely.

8. 📌Postmortem lesions
•There is localized consolidation particularly of the
cranial lobes of lung and the tissue is dark red,
friable and there is no gross evidence of necrosis.
•The lesion present after bacteria infection are
differ according to type of bacteria as pasteurella
sp. And mycoplasma sp cause extensive
heptaization with mottled and red and gray lobules
and fibrinous pleurisy.

9. 📌Diagnosis
• field diagnosis: based on history and
epidemiology of disease, signs of pneumonia
and postmortem lesions.
• Laboratory diagnosis:
• virus isolation on cell cultures.
• serological examination: ELISA, FAT, SNT and
HI tests.
• Histopathological findings.

10. 📌Treatment
• Several antibiotics are of use, including tylosin at
4–10mg/kg body weight, spiramycin at a dose of
20mg/kg body weight
• Expectorants. One drug used at present as a
spasmolytic is bromhexine hydrochloride, which
can be given orally or by intramuscular injection at
a dose of about 0.5 mg/kg body weight for five to
seven days.
• Corticosteroids. The drugs commonly in use
today include dexamethasone, prednisolone.

11. 📌Control
• . Early detection and diagnosis of the disease and isolation of
infected one. Suspected cases should be isolated and received
symptomatic treatment
• Proper management
• Vaccination
• Combined inactivated respiratory virus vaccines (pneumo 3
and pneumo 4)
• The pneumo 3 vaccine contains BVD, IBR, PI-3. The pneumo 4
vaccine contains BVD, IBR, PI-3, and adenovirus. They are used
I/M injection in 2
doses 5 ml/calf for each with 2 week apart
• Cattle Master 4 vaccine (IBR, BVD, PI-3 and RSV)I/M injection of
2 ml in 2 doses with 2-4 weeks apart

13. 🧷Presented by:-
Ahmed Alaa Abdelfattah
🧷 Section no. 1
🧷 Contact:01016235733