Meningoencephalomyelitis in a foal due to Salmonella agona infection.

The research discusses a case of a newborn thoroughbred horse that developed severe meningitis and sepsis due to infection from Salmonella agona, which eventually led to its demise. This occurrence is the first documented case of such a severe Salmonella infection in a horse neonate.

Introduction and Case Presentation

• The subject of the study was a newborn racer horse that reported multiple birth complications such as fractures in ribs and lameness in the front left limb owing to dystocia – a condition characterized by abnormal or difficult childbirth.
• Throughout the course of hospitalization, the foal developed many alarming symptoms like a head tilt, seizures, and watery diarrhea, and unfortunately died seven days post-birth.

Examinations and Observations

• Post-mortem examination of the foal’s brain and spinal cord showed a suppurative meningoencephalomyelitis (an indicative of severe bacterial infection leading to the inflammation of the brain, spinal cord, and their covering membranes) with cases of vasculitis (inflammation of blood vessels).
• Similar pathological signs were observed in the foal’s lungs, umbilicus, and the interstitium (network of tissues) of the kidney’s medulla (innermost part of the kidney).
• The presence of many gram-negative bacilli, a specific group of bacteria, was found within the lesions observed.
• Immunohistochemical analysis was conducted to identify the exact type of the bacilli present in the brain, spinal cord, and umbilicus. The results pointed towards Salmonella Group B.

Cultural Analysis and Findings

• The researchers isolated the bacteria in a pure culture form from various organs viz., the brain, lung, liver, kidney, and intestine. The bacilli were then identified as Salmonella agona.
• This marks the first-ever documentation of complications as grave as meningoencephalomyelitis and septicemia due to an infection caused by Salmonella in a newly born horse.