Aorto-iliac thrombosis in a foal.

The research focuses on the study of a case involving a six-day-old Missouri foxtrotter colt, which showed symptoms of diarrhoea, and was diagnosed with colitis, septicaemia, and disruption of the arterial blood flow to the pelvic limbs. The foal eventually succumbed despite medical intervention, and further investigation revealed multiple health issues, including a large occluding thrombus at the aortic termination.

Clinical Examination and Diagnosis

• The Missouri fox-trotter colt was studied due to its persistent diarrhoea since it was just a day old. This led to the examination and diagnosis of colitis—an inflammation of the colon, septicaemia—a severe infection that spreads via the bloodstream, and disruption in the arterial blood flow to the pelvic limbs.

Medical Intervention and Outcome

• Despite the implementation of intensive medical therapy, the foal failed to survive and died after 13 hours post-examination.

Post-Mortem Examination and Findings

• The post-mortem examination facilitated the identification of multiple severe health conditions. The foal was found to have diffuse fibrinous enteritis, a condition involving inflammation of the intestine with the accumulation of fibrin—a protein involved in the clotting of blood.
• The presence of lymphoid necrosis was noted, which marks the death of lymphoid cells or tissue.
• An occluding thrombus—essentially a blood clot obstructing blood flow, was discovered at the location where the horse’s aorta terminates. This was particularly responsible for the impaired blood flow to the pelvic limbs.
• The foal was also found to be afflicted with multifocal fibrinonecrotic typhlocolitis (localised inflammation and necrosis in the bowels and colon) and disseminated intravascular coagulation—a condition characterised by abnormal blood clot formation and bleeding.

Bacteriological Examination and Conclusions

• Bacteriological culturing was carried out as part of the investigation. The results echoed the original diagnosis of septicaemia.
• The septicaemia, in turn, was identified as the catalyst for triggering the clotting cascade, leading to disseminated intravascular coagulation. This condition was instrumental in causing the aorto-iliac thrombosis and the severe effects on the health of the foal, ultimately causing its premature death.