October 2017



Signalment (JPC # 2127420):  2‑year‑old ewe

HISTORY:  This ewe had sustained severe weight loss over the winter while receiving a ration adequate for maintenance.

HISTOPATHOLOGIC DESCRIPTION:  Lung:  Diffusely, alveolar septa are expanded up to eight times normal by a cellular infiltrate composed of lymphocytes, macrophages and neutrophils admixed with minimal fibrous connective tissue (fibrosis) and small amounts of fibrin and edema.  Multifocally, there is an increased amount of bronchiolar and alveolar smooth muscle (smooth muscle hypertrophy). Multifocally, the peribronchiolar and perivascular connective tissue is expanded by a similar inflammatory infiltrate, increased clear space and dilated lymphatics (edema) and numerous variably-sized aggregates of lymphocytes forming lymphoid follicles with germinal centers.  Multifocally, bronchi and bronchioles occasionally contain amphophilic fibrillar to flocculent material (mucin) that is admixed with sloughed epithelial cells, cellular and karyorhectic (necrotic) debris and/or pale eosinophilic homogenous (seroproteinaceous) fluid, fibrin and small amounts of hemorrhage. 

MORPHOLOGIC DIAGNOSIS:  Lung:  Pneumonia, interstitial, lymphohistiocytic, chronic, diffuse, marked, with peribronchiolar and perivascular lymphofollicular proliferation (BALT hyperplasia) and bronchiolar smooth muscle hypertrophy, breed unspecified, ovine.

ETIOLOGIC DIAGNOSIS:  Ovine lentiviral pneumonia

CONDITION:  Ovine progressive pneumonia (OPP)

CAUSE: Small ruminant lentivirus

Signalment (JPC #2127420):  2-year-old LaMancha goat

HISTORY:  This LaMancha goat had severe weight loss and clinical signs of respiratory disease.

HISTOPATHOLOGIC DESCRIPTION:  Lung:  Lung:  Multifocally, 70% of bronchioles and blood vessels are surrounded by large aggregates of inflammatory cells that form follicles with prominent germinal cells and are composed predominantly of lymphocytes and macrophages with fewer plasma cells (lymphoid hyperplasia).  Diffusely alveolar septa are expanded to up to 50 um by lymphocytes, alveolar macrophages, fewer plasma cells, and fibrosis, and they are often lined by plump cuboidal pneumocytes (type II pneumocyte hyperplasia).  Alveolar lumina are filled with abundant eosinophilic proteinaceous fluid (surfactant and edema), mucin, macrophages with foamy cytoplasm, few neutrophils, cellular debris, and occasional small areas of hemorrhage and mineral.  Bronchi and broncioles multifocally contain edema and mucin admixed with degenerate and viable neutrophils and sloughed epithelium.  Multifocally, the interlobular septa and pleura are expanded up to two times normal by ectatic lymphatics (edema), moderate amounts of fibrin, low numbers of lymphocytes, macrophages, rare eosinophils, occasional mineral and a focally extensive area of mild hemorrhage.  

MORPHOLOGIC DIAGNOSIS:  Lung:  Pneumonia, interstitial, lymphohistiocytic, chronic, diffuse, severe with lymphoid (BALT) hyperplasia, type II pneumocyte hyperplasia and abundant pulmonary edema, LaMancha, caprine.

ETIOLOGIC DIAGNOSIS:  Lentiviral pneumonia

CAUSE:  Small ruminant lentivirus; caprine arthritis encephalitis virus (CAEV)

SYNONYMS:  Lymphoid interstitial pneumonia, maedi-visna (MVV), Graaff-Reinet (South Africa), Zwoegerziekte (Netherlands) and La bouhite (France)










Equine infectious anemia virus  (EIAV)


Human immunodeficiency virus (HIV)


Bovine immunodeficiency virus (BIV)


Jembrana disease (JD)


Feline immunodeficiency virus (FIV)


Simian immunodeficiency virus (SIV)

Nonhuman primate



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