Observations on vascular accidents in the central nervous system of neonatal foals.

This research investigates the occurrence of significant vascular accidents (SVAs) in the central nervous systems of neonatal foals, both alive and dead, and its correlation with the birth process and disease processes. The study uses a special technique to identify these SVAs and suggests that the birthing process may be a major contributing factor.

Study Methodology

• This research employed a specially developed technique for subarachnoid perfusion-fixation of the central nervous system. This technique was utilized on the brains and spinal cords of 24 neonatal foals that were submitted for necropsy (post-mortem examination).

Classification of Significant Vascular Accidents

• Significant vascular accidents (SVAs) were identified as subarachnoid, parenchymal and nerve root haemorrhages, as well as oedema and necrosis.
• These SVAs were found more commonly in the spinal cord as compared to the brain.

Occurrence of SVAs across Different Categories

• The frequency of occurrence of SVAs was similar across different categories: premature and full-term foals, foals born dead and those born alive, and foals born via assisted delivery versus those born unassisted.

Correlation between Neurological Signs and SVAs

• Eight of the live foals in the study showed neurological signs.
• The researchers identified a correlation between the type of neurological syndrome and the site of SVAs. For instance, those foals with syndromes indicative of cerebral disease tended to have brain SVAs. On the other hand, all three cases with signs of spinal cord disease had SVAs located in the spinal cord.

Association between SVAs and Other Diseases

• No specific association was found between the occurrence of SVAs and other disease processes in these foals.
• However, it was noted that two of the prematurely born dead foals, which were infected with equine herpesvirus-1, had SVAs only in the spinal cord.

Comparing SVAs in Live Foals and Foals Born Dead

• Both live foals and those born dead presented a similar distribution of SVAs in the brain and/or spinal cord. Still, the lesions were more severe in the foals born dead.

Conclusions

• The data gathered by the researchers led to the conclusion that the process of birth could be a significant factor contributing to the development of SVAs in neonatal foals.
• The study also suggests that some affected foals may show a syndrome related to spinal cord involvement due to these SVAs.