Serum Bile Acids Concentrations in Healthy and Clinically III Neonatal Foals

Abstract

Background: Reference ranges for serum bile acids (SBA) concentration are well established in healthy adult horses. Increased values are indicative of hepatic disease.Hypotheses: SBA concentrations are significantly greater in the neonatal period compared with mature horses, and illness in the neonatal period will further increase SBA.Animals: Ten healthy mature horses, 12 healthy foals, and 31 clinically ill foals. Methods: Prospective cross-sectional study. Blood samples were obtained once from the mature horses, from healthy foals immediately after birth, at 2 days, and at 1, 2, 3, 4, and 6 weeks of age; and from ill foals less than 1 month of age at the time of admission to the Veterinary Teaching Hospital. SBA concentrations were determined enzymatically and by radioimmunoassay. Total and direct bilirubin and triglyceride concentrations were measured, as well as sorbitol dehydrogenase (SDH) and c-glutamyltransferase (GGT) activities.Results: There was a significant negative correlation between age and SBA concentration. Compared with mature horses, SBA concentrations were significantly greater in healthy foals at each collection time over the first 6 weeks of life. Radioimmunoassay values were lower than enzymatic SBA values, with increasing bias as the mean difference between values increased. When comparing age-matched values between healthy and ill foals, there were no significant differences in SBA. None of the ill foals had a primary diagnosis of hepatic disease. There was no significant correlation between the SBA concentration and the bilirubin or triglyceride concentrations or the GGT activity. There was a significant direct correlation between increased SBA and serum SDH activity in healthy foals only.Conclusion and Clinical Importance: SBA concentrations in foals are significantly higher in the early neonatal period, underscoring the importance of using age-matched references when evaluating clinical pathology values during the neonatal period.

Plasma iron concentrations and systemic inflammatory response syndrome in neonatal foals

“…27 Other markers of systemic inflammation currently validated in equine neonatology are plasma fibrinogen, serum amyloid A 28,29 and C-reactive protein concentrations. 30 In and as explained before, colostrum and milk are the major source of iron for newborns. Perhaps measuring plasma and colostrum/milk iron concentration of the mares and the amount of colostrum ingested would have been useful in explaining the differences between the control populations.…”

“…Age differences between the stud control and healthy hospitalized foals (1.5 versus 4.5 days, respectively) could at least partly explain the differences observed in plasma iron concentrations (Figure 2). To rule out the age effect in future studies, we suggest classifying foals according to age (ie, 1‐3 days, 3‐7 days, and <14 days), in order to differentiate plasma iron concentrations in SIRS and non‐SIRS neonates as some other authors have done measuring age‐dependent plasma biochemical variables in neonatal foals 31 …”

Physiological variations of serum biochemical profile in quarter horse mares at peripartum and in their neonatal foals

“…This result is similar to the findings of Patterson and Brown (1986), who reported that serum GGT activity in Standardbred foals was significantly superior to that of the mares. It should be emphasized that GGT levels on the day of birth is not a result of colostrum ingestion, as observed in ruminants, once mares have low levels of GGT in the colostrum (AOKI; ISHII, 2012;BARTON;LEROY, 2007). These 976 Physiological variations… BARBOSA, F. C. et al higher levels in the foals, thus, may be an indication that serum GGT levels are probably a result of endogenous sources (PATTERSON; BROWN, 1986).…”