A retrospective study of increased plasma progestagen concentrations in compromised neonatal foals.

The research article details a study looking into the plasma progestagen concentrations in sick newborn foals. The study suggested that there might be a link between adrenal stimulation and an enzyme block, contributing to the overproduction of pregnenolone (P5) and pregnenediol (P5 beta beta) in these foals.

Methodology

• The study followed a sample of 35 sick foals retrospectively and tracked their condition by measuring plasma progestagen concentrations daily through radioimmunoassay (RIA).
• The foals were divided into three groups based on how quickly they were able to stand after birth and offered the necessary intensive care according to their individual health severity.
• Additional measurements were made to assess the renal and respiratory status of the foals. This was done by measuring creatinine clearance ratios and arterial oxygen concentrations.
• P5 and P5 beta beta concentrations in plasma and urine were measured using gas chromatography-mass spectrometry.
• Plasma cortisol concentrations, indicators of stress in the body, were also measured by RIA.

Findings

• The study recognized five patterns of plasma progestagen concentrations in the foals. Typically, the progestagen values escalated when the foal’s health deteriorated and decreased as their health improved.
• The foals in Group 1, who were faster to stand after birth, showed decreased median progestagen concentrations over the first three days. Groups 2 and 3, however, maintained elevated progestagen levels.
• Similar tendencies were observed in P5 and P5 beta beta concentrations.
• Cortisol concentrations in the plasma were highest among foals in groups 2 and 3, suggesting higher levels of stress.
• Regardless of the group, foals treated with adrenocorticotrophic hormone displayed the highest mean cortisol concentrations. No significant correlation was found between plasma cortisol and progestagen concentrations.
• The factors of renal clearance, steroid conjugation, and respiratory status did not significantly influence the increase in progestagen concentrations in unwell foals.

Hypothesis

• The research concludes hypothesizing a probable link between adrenal stimulation and an enzyme block in sick young foals. This might be causing overproduction of P5 and P5 beta beta in the foals.