Clinical and radiographic findings in Corynebacterium equi pneumonia of foals

Abstract

Thirty-nine foals with pneumonia were admitted to the Veterinary Medical Teaching Hospital at the University of California, Davis. Corynebacterium equi was recovered from each of them on bacteriologic culture of transtracheal aspiration specimens or lung specimens at necropsy. The foals were divided into 2 groups. Group I consisted of 20 foals that died because of C equi pneumonia and were subsequently necropsied. Group II consisted of 19 foals that were treated and discharged from the hospital. Radiography was performed on all foals. Clinical signs included increased respiratory rate, fever, cough, nasal discharge, increased bronchovesicular sounds over large airways, and wheezing over small airways. Highly significant differences were found in the mean respiratory rate (P less than 0.005) and temperature (P less than 0.001), recorded at admission, between the 2 groups; both factors were higher for group I. Hematology revealed leukocytosis with neutrophilia, monocytosis, and high plasma fibrinogen content in all foals. Significant differences were recorded in the mean total leukocyte count (P less than 0.05), mean neutrophil count (P less than 0.05), mean monocyte count (P less than 0.005), and mean fibrinogen value (P less than 0.05) between the 2 groups; values from group I were higher than those from group II. Although C equi was isolated alone from 25 of the tracheal aspirates and lung specimens, 14 cultures yielded multiple pathogens. At the time of initial examination, all foals had radiographic evidence of pneumonia. Pulmonary consolidation indicative of bronchopneumonia was identified in 31 of the 39 foals.(ABSTRACT TRUNCATED AT 250 WORDS)