SURVEY OF ANAPLASMA PHAGOCYTOPHILUM ANTIBODIES IN CAPTIVE PRZEWALSKI’S HORSES (EQUUS FERUS PRZEWALSKII).

The research article focuses on the survey and analysis of Anaplasma phagocytophilum antibodies in captive Przewalski’s horses, exploring its prevalence, the associated gender differences, and a potential correlation with age.

Introduction and Background

• The study looks into Anaplasma phagocytophilum, a tickborne pathogen that is known to infect domestic horses and leads to a condition called equine granulocytic anaplasmosis.
• Following the identification of clinical anaplasmosis in a captive Przewalski’s horse at the Smithsonian Conservation Biology Institute in 2008, researchers decided to conduct an opportunistic serosurveillance of the herd.

Research Methodology

• Within a period of 2008 to 2014, the researchers gathered 57 serum samples from 27 Przewalski’s horses, including 10 males and 17 females.
• The study applied indirect immunofluorescent antibody assays to detect antibodies against Anaplasma phagocytophilum within these samples.

Findings and Analysis

• The research findings show a high prevalence rate of 53% of Anaplasma phagocytophilum antibodies in the sampled population. This suggests that over half of the captive Przewalski’s horses had been exposed to the pathogen.
• The study found no significant differences in the prevalence between male and female horses.
• An interesting discovery was a statistical association between increasing age of horses and seropositive status, suggesting that older horses carry a cumulative risk of exposure to Anaplasma phagocytophilum.
• Upon excluding four clinical cases of anaplasmosis from the analysis, it was found that every year, between 22% to 57% of the horses sampled were seropositive despite being clinically normal. This indicates that most Przewalski’s horses develop subclinical or self-limiting anaplasmosis after exposure to the pathogen.