Letter: Experimental infection of a horse with an equine adenovirus.

The research article reports an experiment done on a Thoroughbred yearling to examine the effects of equine adenovirus. The foal, isolated from other horses, was inoculated with the adenovirus and the changes were observed over a period of 72 days.

Introduction

• This research article details a scientific investigation where a Thoroughbred yearling was deliberately infected with an equine adenovirus, the results of which had not been reported in previous scientific literature.
• While there have been instances of foals succumbing to natural adenovirus infection, this study aimed to experimentally introduce the virus into a horse and monitor the ensuing changes in its health condition.

Methodology

• Before the adenovirus infection was initiated, a serum sample, nasal, and ocular swabs were obtained from the yearling.
• Around 5 ml of a suspension of equine adenovirus, strain EAM-I, was then inoculated onto the nasal mucous membrane of the yearling.
• Throughout the three-week observation period, various health parameters including temperature, heart rate, respiratory rate, haemoglobin levels, erythrocytes, packed cell volume, serum protein, serum glutamic-oxaloacetic transaminase median corpuscular haemoglobin content, total, and differential white cell counts were meticulously recorded every second day.
• Determination of antibody levels to the EAM-I strain was performed using serum neutralisation, complement fixation, haemagglutination inhibition and gel diffusion tests.

Observations

• Nasal and ocular swabs were collected on the same days as blood samples, and virus isolations were attempted with using monolayers of primary equine foetal kidney cells.

Procedure

• The yearling was kept in isolation from other horses for the 72-day observation period to avoid any cross-contamination and interference with the experiment.
• After 72 days of close monitoring, the yearling was reintroduced to other horses.
• At this point, additional blood samples were taken for further testing and investigation.