Evaluation of lung maturity by amniotic fluid analysis in equine neonate.

This study was aimed at evaluating lung maturity in newborn horses using the analysis of amniotic fluid. The research employed techniques traditionally used in human medicine to assess potential methods for an earlier prognosis, hoping to increase the survival rate of equine infants by offering more timely and cost-effective treatment options.

Study Design and Methodology

• The study involved the collection of amniotic fluid from 18 mares at the time of giving birth. Isolating lamellar bodies, a type of cellular structure found in the lung, from the amniotic fluid was an essential step.
• The next part of the process involved the measuring of these lamellar bodies with transmission electron microscopy (TEM), which provided a detailed view of these minute particles in a highly magnified manner.
• The study also involved two conventional tests employed in human medicine: the lecithin/sphingomyelin ratio (L/S) test – which measures the ratio of two essential lung maturity markers and the lamellar body count (LBC) – an enumeration of lamellar bodies in the amniotic fluid.
• The L/S ratio was determined using a technique known as thin layer chromatography (TLC) and, for the first time in this kind of study, with high performance liquid chromatography (HPLC).
• LBC involved using an automated blood cell counter to accurately count the number of lamellar bodies.

Results and Findings

• The mean (average) L/S ratio results from mature foals were found to be 2.5 with TLC and 2.7 with HPLC. The mean LBC in the same group was 48×10(3)/microL.
• A significant correlation was found between TLC and the Apgar score (a quick test performed at 1 and 5 minutes after birth), between TLC and cord pH (the acidity or alkalinity measure of blood in the umbilical cord at birth), and between HPLC and Apgar score. Also, between cord pH and the Apgar score, a remarkable association was discovered.
• The Student’s t-test, a statistical test comparing the means of two samples, revealed no significant difference between the L/S ratio performed with TLC and with HPLC.

Conclusions and Suggestions for Future Research

• The study concludes that these methods could potentially be used for assessing lung maturity in newborn horses.
• While the initial results seem promising, the researchers stress the need for further research involving a larger sample size of both mature and premature foals to devise a standard measure for equine lung maturity.