In the diagnosis of liver diseases the determination of plasma bile acid co
ncentration (PBAC) is used as an endogenous liver function test. To avoid f
alse positive results it is recommended to obtain blood samples after a fas
ting period of 12 hours or to use a separate reference range when taking po
st-prandial blood samples.
In this study the post-prandial development of the PBAC in psittaciformes i
s examined to determine the appropriate time for diagnostic blood withdrawa
l.
For this purpose the PBAC of 6 grey parrots (Psittacus erithacus) was deter
mined every two hours for 12 hours after feed deprivation and of 6 goffin's
cockatoos (Cacatua goffini) and 12 amazons (Amazona spec.) over 8 hours af
ter feed deprivation (following ad libitum feeding before).
In the goffin's cockatoos the PBAC reaches a level after the 2 hour measure
ment and in the grey parrots after the 4 hour measurement, that implies the
recommendation of 20-100 mu mol/l as reference range, if a minimal fasting
period of 2 hours for the goffin's parrots and 4 hours for the grey parrot
s is allowed.
In the amazons the development of the individual PBAC was so variable, that
no direct post-prandial time period can be defined. In this genus of psitt
aciformes a reference range of 20-140 mu mol/l should be used, independent
of the last time of feed intake.