Interrelation between frequency of anti-leptospira spp. Antibodies and findings of histopathological examinations (hematoxylin-eosin and warthin-starry) in pigs slaughtered in the semiarid of Paraiba state, northeastern Brazil

Abstract

This work was conducted in slaughtered pigs in Patos County, Paraiba State, Brazil, with the aim to determine the frequency of anti-leptospira antibodies and to compare the serological findings with the histopathological findings of kidney, liver, ovary and uterus. The microscopic agglutination test (MAT) was performed on 126 animals. The histopathological examination performed in sections of livers, kidneys, ovaries and uteruses stained with hematoxylin-eosin (HE) was conducted in 20 randomly chosen animals (10 from group with serological titer > 100 and 10 from group < 100). Parallel to this, a direct search for leptospires was carried out by Warthin-Starry technique in kidney samples from all seropositive animals and in the 10 seronegative animals submitted to HE. In the 126 animals examined, 18 (14.6%) were seropositive, with prevalence of reactions to Autumnalis serovar (11 animals; 8.73%). Four seropositive and two seronegative animals showed different degrees of inflammatory infiltrate and necrosis in liver or kidney. The ovaries and uterus no showed lesions. Direct analysis of leptospires by the Warthin-Starry technique did not reveal positive animals in any sample tested. The rate of seropositivity found (14.6%) suggests the importance of awareness by producers about the implementation of preventive measures aimed at preventing, or at least reducing the spread of leptospiras in pigs and thereby blocking the possible transmission of the agent to humans