Top Pig Diseases to Know for Boards Success Part 1_Respiratory conditions _ Zuku Review

What is Porcine Reproductive and Respiratory Syndrome (PRRS)?

PRRS is the most costly pig disease worldwide, characterized by a range of symptoms in pigs including mild to severe respiratory issues and high neonatal mortality.

What are the effects of PRRS in breeding herds?

PRRS may cause mild to severe abortions, early farrowing, anorexia, and up to 100% neonatal mortality.

What is the primary diagnostic method for detecting PRRS?

Diagnosis can be performed through necropsy, histopathology, and serological tests such as ELISA.

What are key clinical signs of Influenza A virus (IAV) in pigs?

Sudden onset of fever, cough, nasal discharge, and 100% morbidity, especially prevalent in younger pigs.

How is IAV typically diagnosed in pigs?

Diagnosis can be made through gross lesion examination, microscopic examination of lung tissue, and PCR testing.

What is the primary treatment approach for pigs infected with IAV?

Supportive care, including the use of NSAIDs to reduce fevers and treating secondary bacterial infections.

What is Actinobacillus suis and its significance in pig health?

A. suis is a bacterial disease that can cause respiratory issues and acute death across all age groups of pigs.

What lesions are commonly associated with A. suis infection?

Visible lesions may include petechial to ecchymotic hemorrhages in multiple organs and sero-fibrinous exudates in cavities.

How do pigs typically contract Actinobacillus suis?

The disease spreads nose to nose among pigs.

What is the importance of vaccinating for Porcine Circovirus diseases (PCV2)?

Vaccination is crucial as PCV2 can lead to severe syndromes, and the prognosis is poor in unvaccinated pigs.

What is the classic age range affected by Mycoplasma hyopneumoniae?

Typically affects late finishing pigs over 15 weeks of age.

What are the significant clinical signs of Mycoplasma hyopneumoniae infection?

Deep, barking, and/or non-productive cough, along with poor growth patterns.

What is the classic presentation of Atrophic Rhinitis in pigs?

Sneezing, nasal discharge, tear staining, and decreased growth rate, mainly in three- to six-week-old pigs.

What are common diagnostic findings in pigs with Atrophic Rhinitis?

Mild to moderate turbinate atrophy and disruption of normal bone formation in the turbinates.

What is the main treatment strategy for Atrophic Rhinitis in pigs?

Vaccination of sows before farrowing and providing antimicrobial treatment at parturition.

PRRS clinical signs?

They can be subclincal, i.e. pigs have no CS.

In the breeding herd the CS vary from mild to severe. See abortions, early farrowing, anorexia and up to 100% mortality in neonatal pigs.

In growing pigs see transient diz w/ up to 20% morality. Cough, fever and sec. inf. with streptococcus, glaeserella parasuis and mycoplasma are common.

PRRS etiology

RNA Arterivirus, has many different strains. It invades the pulm. alveolar macrophagesand causes immune suppression, leading to secondary infections.

Necropsy PRRS?

Lungs fail to collapse w/ multifocal consolidation, enlarged LNN

Histopath. findings PRRS?

Necrotizing interstitial pneumonia, lymphoid hyperplasia and focal follicular necrosis

PRRS Dx?

Perform ELISA or PCR on oral fluids or serum of sows and newly weaned piglets. PCR on lungs

PRRS Tx?

No spec. tx, supportive care - prevent sec. infections. Its very common, low level doesnt cause significant economic losses, can just monitor.

How to prevent PRRS?

Its highly infective and cont. Biosecurity is key, test new animals before entry.

Influenza A virus CS?

Acute - transient disease, worse in pigs, better in vaccinated pigs, see CS:

1. sudden onset of fever and cough

2. 100% morbidity

3. Nasal discharge

Endemic IAV in sows and nursery pigs, see:

1. Poor reproductive performance

2. Piglets coughing in farrowing crates

3. Cough and poor performance in nursery

Influenza etiology?

Influenza A virus, major Ag types in swine are H1N1 and H3N2

Necropsy and histopath. findings in influenza?

Gross lesions - sharply demarcated multifocal areas of consolidation

Microscopic lesions:

1. Degeneration and necrosis of the epithelium in the bronchi and bronchioli

2. Hyperemia and dilatation of the capillaries

3. Infiltration of the alveolar septae with Ly etc.

Influenza Dx?

PCR on oral fluids (less commonly virus isolation). Nasal swabs on febrile pigs for PCR. PCR of lung tissues

Influenza Tx?

In an outbreak:

1. Supportive care with aspirin, NSAIDs like flunixin meglumine

2. Get fever down so pigs can eat and drink

3. Tx sec. bact. inf. with ABx

Influenza prevention?

Vaccination of sows and piglets, homologous protection is best

CS of actinobacillus suis?

Acute death:

1. Affects all ages from sows and neonates to finishing pigs

2. May be accompanied by cough, lethargy, epistaxis and sometimes discoloration of ears

Respiratory diz in finishing pigs:

1. Dyspnea

2. Acute death

What is actinobacillus suis?

An ubiquitous small G- rod

Actinobacillus suis Dx?

Culture visible lesions

Necropsy findings A. suis??

1. Petechiae to ecchimotic hemorrhages in multiple organs

2. Serous to serofibrinous exudates in the thoracic and abdominal cavities

3. Pleuritis, pericarditits, arthritis and miliary abscesses in a variety of organs

Microscopic lesions A. suis?

• Foci of necrosis in multiple organs associated with bacterial thromboemboli

A. suis Tx?

1. ABx

2. Spread nose to nose so inject ABx into those pigs that have nose to nose contact with pigs that died

3. Follow up with ABx in the water

4. Good prognosis with Tx

Porcine circovirus 2 CS?

Pigs early in grower (>10wks) have 2 syndromes:

1. Post weaning multisystemic wasting syndrome (PMWS) with diarrhea

2. Porcine dermatitis and nephropathy syndrome with pale to icteric skin with coalescing raised red to purple lesions covering the rump

Gilts in sow heards:

1. Increased mummified fetuses

2. Late term abortions

What type of virus is PCV2?

A small, nonenveloped DNA virus

Necropsy PCV2?

1. Enlarged LNN

2. Lungs dont collapse with interlobular edema

3. Kidneys are enlarged and pale and subscapular surface may have spotted white foci

Microscopic lesions PCV2?

1. Lymphocytic histiocytic infiltration of lymphoid tissues

2. Sloughing of lung epithelium with fibroplasia

PCV2 Dx?

PCR on oral fluids

IHC or PCR on lung and LNN

Histopath. lesions PCV2?

Lymphocytic histiocytic infiltration of lymphoid tissue

PCV 2 Tx?

No tx, prevent with vaccination. Poor Px if unvaccinated.

Enzootic pneumonia CS?

Late finishing pigs (>15wks) have deep, barking and non productive cough and they stop growing.

Can occur in sow farms if + pigs are introduced to - farm/

Enzootic pneumonia etiology?

Mycoplasma hyopneumoniae, a slow growing bacterium

Necropsy and histopath. enzootic pneumonia?

Gross:

1. Cranioventral consolidation (apical, cardiac and accessory lobes)

Microscopic lesions:

1. Lymphocytes in perivascular, peribronchial, and peribronchiolar tissues

2. Cuffing and lymphoid hyperplasia around the airways

Enzootic pneumonia Dx

1. PCR: lungs, oral fluids, tonsil scrapings

2. ELISA in negative herds

Enzootic pneumonia Tx?

ABx during outbreaks in late finishing pigs, hard to eliminate cough.

Prevent: vaccination in piglets 2x, in replacement gilts depending on status of sow heard they are entering.

Atrophic rhinitis CS

3-6wk old pigs:

1. Sneezing

2. Nasal discharge

3. Tear staining

4. Decreased growth rate

Atrophic rhinitis etiology?

Cause is a combination of B. bronchiseptica ± toxigenic P. multocida + management factors (like poor air quality)

Necropsy and histopathology atrophic rhinitis?

Gross lesions:

1. Mild to moderate turbinate atrophy

2. ± Devination of nasal septum

Microscopic lesions:

1. Disruption of normal bone formation in the turbinates

Atrophic rhinitis Tx?

ABx to sows post partum, vaccinate sow 2x pre farrowing, piglets twice