Mare Reproductive Loss Syndrome Essay Example | Topics and Well Written Essays - 500 words

Mare Reproductive Loss Syndrome - Essay Example t the weather at that time in March was unusually cold followed by above normal temperatures in April, which stimulated rapid plant growth and concurrent increase in the number of eastern tent caterpillars. Wild Cherry trees were the principal source of food for these caterpillars. Lack of abortion in areas where these caterpillars did not exist and later experimental intragastric inoculation of pregnant mares with caterpillar extracts confirmed the reason for these abortions (merckvetmanual.com). The MRLS syndrome in addition to early/late fetal loss is characterized by uveitis, pericarditis and encephalitis and occurs due to tissue penetration by barbed setal fragments from Eastern tent caterpillars, Malacosoma americanum (Tobin et al, 2004). After ingestion the barbed setal fragments migrate through moving tissues followed by rapid spread of bacteria, bacterial emboli and septic fragments of setae, collectively known as septic materials (Tobin et al, 2004). A number of bacteria are carried by the setal fragments in moving tissues, blood, uterus and fetal membranes of pregnant mares. Pharmacokinetic studies and studies on the structure of the setae revealed barbs on them which facilitated the rapid spread of bacteria as hitchhikers. Clinically affected tissues show a poor antibacterial response as bacterial contamination of tissues and extracellular fluids is very rapid. It has been proposed that MRLS also includes an immunosuppressive mechanism which predisposes the affect ed horses to opportunistic bacterial infection (Flaminio et al, 2005). Pathological lesions when MRLS is suspected are consistent with bacterial infection as the cause. Streptococcus, Actinobacillus species and Serratia were some of the prominent bacterial species isolated from horses suffering from MRLS. Sebastian M.M. et al (2008) propose two hypotheses for MRLS. According to one, the syndrome is produced due to an Eastern tent caterpillar toxin complicated with secondary bacterial