Hematology and blood chemistry of the marsh harrier (Circus aeruginosus)

Hematocrit and plasma chemistry values in adult collared scops owls (Otus lettia) and crested serpent eagles (Spilornis cheela hoya)

In this study, we report hematocrit and plasma chemistry values for adult captive collared scops owls (Otus lettia) and crested serpent eagles (Spilornis cheela hoya). In particular, we address the gender-specific differences within these values. We measured hematocrit (HCT) and plasma chemistry values for uric acid (UA), plasma urea nitrogen (BUN), total protein (TP), albumin (ALB), glucose (GLU), cholesterol (CHO), triglyceride (TG), aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), total bilirubin (TBIL), creatine (CRE), creatine phosphokinase (CPK), amylase (AMY), calcium (CA), ionic phosphorous (IP) and sodium (NA), potassium (K) and chloride ions (CL) in 37 adult captive collared scops owls and 39 adult captive crested serpent eagles. Significant differences between the sexes were found for UA, GLU and CPK in the collared scope owls. UA and GLU concentrations were significantly higher (P<0.01 and P<0.05) among males than females, while the CPK concentration was significantly lower (P<0.05) in males. There were no significant differences in of all of the measured parameters between male and female eagles. These finding suggested that HCT and plasma chemistry values of raptors vary individually according to species and sex. Our results provide the 1st available reference data for ranges of plasma values in adult captive collared scops owls and crested serpent eagles, making them a potentially useful complementary diagnostic tool for veterinary care of individuals for both species in captivity.

Blood chemistry and hematologic values in free-living nestlings of Montagu's harriers (Circus pygargus) in a natural habitat

The establishment of reference intervals for hematologic and blood chemistry values in a given species is essential for subsequent diagnosis of disease at rehabilitation facilities and in captive breeding programs. In this study, blood samples were obtained from nestlings (18 males and 22 females) of a natural-vegetation breeding population of Montagu's harrier (Circus pygargus) in eastern Spain in order to establish reference intervals for blood values. This is the first study documenting hematologic and biochemical reference intervals for free-living Montagu's harriers. The studied population may reflect typical blood values for the species, since it is a free-living population that seems not to be constrained by food availability, as it is the population of Montagu's harriers with the highest productivity within Europe. Differences related to sex, year, clutch size, brood size, and number of fledglings were analyzed. Packed cell volume and hemoglobin were significantly lower from nests with five chicks compared to values from nests with fewer chicks, indicating that the cost of rearing more than four chicks in this species may be excessive. Total protein, calcium (Ca), and phosphorus (P) were significantly lower in the year with lowest mean rainfall, which correlates with the worst breeding success rate since the population has been monitored. No gender differences were found; this is likely a result of the prepubertal age of the animals sampled.

Total plasma protein level as an indicator of condition in wild American kestrels (Falco sparverius)

Total plasma protein levels were determined for 292 female and 228 male American kestrels (Falco sparverius) in the wild. Plasma protein levels were significantly higher in females than in males, and higher during prelaying than during incubation. For both sexes, plasma protein levels did not vary significantly with the number of days before or after egg laying on which the sample was taken, time of sampling, prey abundance, age, molt, or infection by the blood parasite Haemoproteus sp. Protein levels in females increased with date of sampling and body condition during prelaying, while the same pattern was seen in males during incubation. With the exception of those of prelaying females, plasma protein levels increased with ambient temperature. The results of this study suggest that at least some of the variation observed in total protein levels is attributable to physical condition. However, further investigation is required before the reliability of using total plasma protein level as a tool to assess the health and condition of kestrels is known.