Histopathologic lesions in conventional pigs experimentally infected with Haemophilus parasuis serovar 5.

OBJECTIVE: In the present study various tissues of pigs were investigated for the presence of histopathologic lesions after an experimental infection with Haemophilus (H.) parasuis serovar 5. MATERIAL AND METHODS: Conventional pigs (n = 36) were divided into a control group B (n = 9) and a challenge group A (n = 27), which was infected intratracheally. Pigs that did not die prior to study termination were euthanized on day 14 post inoculation. Postmortem samples of the lung, heart, liver, kidney, spleen, left tarsal joint capsule and brain were collected. RESULTS: All but one pig with detectable histopathologic lesions (n = 11) showed typical macroscopic changes. Histopathologic examination of all tissue samples identified pyelitis (n = 10), synovitis (n = 7) and meningitis (n = 7) and all those animals were euthanized prior to study termination. No histopathologic lesions were found in pigs of the control group. The correlations between pyelitis and meningitis, pyelitis and synovitis and synovitis and meningitis were significant (p < 0.001). No significant correlation could be observed between the histopathologic and the clinical examination of the joints. The investigation of samples from the joints by PCR was not significantly correlated with the observed synovitis. The clinical observation of neurologic signs was significantly correlated with meningitis (p = 0.03). A significant correlation (p < 0.001) could be detected between meningitis and the detection of H. parasuis by PCR in brain samples. CONCLUSIONS: H. parasuis constantly causes clinical signs and pathologic lesions as soon as it infects the brain while it can infect the joints without causing histopathologic lesions. Pigs with histopathologic lesions do not always show typical clinical signs. Only few studies described the finding of kidney lesions in pigs with Glässer's disease and this is the first study to describe a pyelitis in pigs experimentally infected with H. parasuis. The observed pyelitis mainly occurred in acute cases.

Microscopic and ultrastructural lesions of the ureter and renal pelvis in sows with regard to Actinobaculum suis infection.

Tissues from ureter and renal pelvis of 18 sows naturally (n = 15) and experimentally (n = 3) infected with Actinobaculum suis (former Actinomyces, Eubacterium suis) were studied using light and scanning as well as transmission electron microscopy. The results were compared with the findings from 11 clinically healthy sows as controls. The lesions in both the ureter and renal pelvis of naturally and experimentally infected animals were similar. In severe cases there were necrotizing ureteritis and pyelitis with accumulation of bacterial colonies in some cases. Several superficial epithelial cells were found phagocytosing necrotic debris. In mild cases the main lesions included epithelial cell hyperplasia, desquamation of the superficial epithelial cells and goblet cell metaplasia with intraepithelial cyst formation. The goblet cells were found in the superficial as well as in the intermediate cell layers. Generally, it was observed that severe purulent ureteritis and pyelitis/ pyelonephritis in sows were to be expected only in mixed infection of A. suis with other bacteria. The findings were compared and discussed with the changes in the infected urinary bladder of sows and the alterations induced by urinary tract infection in man.

[Pyelocystitis in breeding sows]. / Die Pyelozystitis der Zuchtsau.

Pyelocystitis results from ascending infection of the urinary tract with Corynebacterium suis in sows. Infection occurs regularly during coitus by healthy boars, which are often contaminated with Corynebacterium suis. Characteristic clinical signs of pyelocystitis are haematuria, anemia and emaciation. The whole urinary tract shows severe purulent-necrotic inflammation with progressive vascular lesions. Diagnosis is based on clinical, pathological and bacteriological findings. Distinct changes in urine samples are present. Treatment is only successful in sows with intact function of kidneys. In early detected cases treatment can be effective with repeated application of appropriate antibiotics, e.g. penicillin or ampicillin. There are no proven methods of prevention.

[Isolation of group D streptococci in pyelitis cystica of swine]. / Izolirane na streptokoki ot grupa D pri tsistopielit po svinete.

A disease was noted among the replacement sows on a pig-breeding complex, exhibiting signs of pyelonephritis, cystitis, and metritis. Bacteriologic studies revealed the presence of streptococci. Streptococcus typing was carried out by means of biochemical, immunodiffusion, and immunoelectrophoretic investigations. The isolated strains were shown to belong to group D--Str. suis. The treatment of HCL-extracts to D-group streptococci with pepsin considerably raised the value of the respective immunoelectrophoretic method in the process of typing.

[Studies of the etiology of cystopyelitis in hybrid swine]. / Prouchvaniia vurkhu etiologiiata na tsitopielitite po khibridnite svine

Studies were carried out on the etiology, clinical picture, morphologic changes, and methods of prophylaxis of the cystopyelitis in hybrid pigs. It was established that in the cases studied the etiologic part is most probably played by Escherichia coli having pronounced virulence for albino mice. Clinically the disease was manifested with hematuria--the cardinal diagnostic symptom; histologically there were nephritis, pyelonephritis, and strong edemas on the wall of the bladder. When hematuria appeared the affected pigs died (at the rate of 100 per cent) as a result of acute anemia. Prophylactic measures have been especially successful with the use of streptomycin to which the isolated coli strains proved sensitive.

Frequency of pyelitis, pyelonephritis, renal perivasculitis, and renal infarction in dogs.

The frequency of pyelitis, renal perivasculitis, and renal cortical inflammation was determined in 104 apparently normal dogs, 50 dogs with disease that were necropsied, and 20 dogs with experimentally induced cystitis. Abnormalities occurred least often (19%) in the apparently normal group and most often (55%) in the cystitis group. The frequency of specific lesions was generally higher in males than in females. Bacteria were isolated from kidney and urine of some of the apparently normal dogs, but their relationship to the lesions observed was not established.