Clinical Pathology
A minimum database of clinical pathology should be obtained to establish a
baseline and determine the degree of organ dysfunction. On problem farms
or with valuable foals it may be prudent to run blood samples in the apparently
healthy foal. The author would advise routinely running a haematology, SAA,
fibrinogen, TSP (alb and glob), IgG and creatinine on day 2 of life (>18 hrs of
age). Many foal values are different to adult values, and then changing in the
first few days, weeks and months of the foal’s life so it is imperative to ensure
that the correct reference ranges are used relating to the age of the foal.
Laboratory data to consider collecting includes:
Haematology
Biochemistry (including inflammatory proteins SAA and fibrinogen)
Electrolytes
IgG levels
Blood glucose
Blood lactate
Blood cultures
Urinalysis
Faecal culture/toxin assays/ELISA
Blood pressure
Blood gases
Haematology
PCV/RBC count - The PCV and Hb values reach adult values by 300 days
gestation, then drops over first 2 weeks of life, (influenced by transfer of
placental blood flow, catecholamine secretion and fluid balance adjustment
(osmotic effect of colostral immunoglobulins)).
Low RBC count – premature cord rupture, NIE (often with jaundice) or
haemorrhage (can be secondary to ulceration), occasionally immune
mediated (can be drug related).
Haemoconcentration – dehydration - lack of suckling and/or fluid loss e.g.
septicaemia, acute enteritis.
WBC count – Although most healthy foals are born with a total WBC count
similar to that of adults, there can be a wide normal range. In utero, absolute
neutrophil values are low (<1.5 x 10 9/l) upto 300 days of gestation, increasing
to a mean of 5.5 by birth. Band neutrophils should be absent in the healthy
foal and the importan