Black-faced spoonbills (Platalea minor) belong to the family Threskiornithidae, which includes ibises and spoonbills. They are endemic to east Asia and listed as endangered by the IUCN criteria. The total population is currently estimated at 1000 individuals. The three major wintering grounds are in Taiwan, Hong Kong and in Vietnam. Up to 25% of the world’s population winters in Hong Kong. The black-faced spoonbill is a flagship species for wetland conservation in Hong Kong.
ISIS physiologic reference database does not contain reference ranges for black-faced spoonbills. The aims of this project were to obtain baseline data for blood values in this species and to provide useful information which can be used to assess ill or injured black-faced spoonbills presented for treatment and rehabilitation.
In December 2002, 11 black-faced spoonbills were captured using a rocket net in Mai Po Marshes Nature Reserve, Hong Kong to be fitted with leg-mounted radio-transmitter to gather information about their utilization of wetland habitats and to investigate the specie’s nocturnal behavior.
Six birds were physically examined. Two milliliters of blood were obtained from the jugular or ulnar vein of each bird, then stored in potassium EDTA and lithium heparin. Two air-dried smears were obtained from whole blood. The smears were examined for the presence of hemoparasites. The EDTA blood was processed for hematology using the Unopette method. The following biochemical parameters were obtained: calcium, phosphorus, total protein, albumin, globulin, uric acid, AST, LDH, glucose, CK, bile acids, zinc, and lead. Two to three drops of blood were used for DNA sexing.
Results and Discussion
Based on physical examination, all birds were healthy at capture. Three birds were male, and three were female. Ranges based on 90% confidence intervals are the following: RBC (106/µl) 2.67–3.10, PCV (%) 42.57–48.76, WBC 9,305–17,315/µl, heterophils 75–86%, lymphocytes 7–19%, monocytes 2–6%, eosinophils 0–2%, basophils 1–2%. The following ranges were calculated for biochemistry values: calcium (mg/dl) 7.53–7.84, phosphorus (mg/dl) 2.20–3.15, total protein (g/L) 29.63–34.51, glucose (mg/dl) 238–278, AST (U/L) 278–405, LDH (U/L) 263–488, CK (U/L) 2597–7067, uric acid (mg/dl) 3.00–7.33, serum bile acids (µg/ml) 1.61–5.75, and zinc (ppm) 1.89–2.35.
Although these data are based on samples from only six birds, they provide a useful working reference for veterinarians treating this species of bird.
The authors wish to thank Hong Kong Agriculture, Fisheries and Conservation Department for granting the permit allowing blood collection, and funding the tracking study, Alexandro Grioni and Vicky Elliot for their assistance with the blood collection, Gail Cochrane, Paul Leader and Ocean Park Corporation for allowing us to complete this project.
1. Walton, R.M. 2001. Establishing reference intervals: health as a relative concept. Semin. Avian Exotic Pet Med. 10(2):66–71.