Raptor hematology and chemistry evaluation

HEMATOLOGY AND PLASMA BIOCHEMISTRY REFERENCE INTERVALS FOR FREE-LIVING ADULT CHIMANGO CARACARA (MILVAGO CHIMANGO) DURING THE NONBREEDING SEASON

Hematological and blood biochemistry values are useful in assessing the physiological, nutritional, and overall health status of captive and free-living wildlife. For the chimango caracara (Milvago chimango), the most common raptor species in Argentina, reference intervals (RIs) for hematology and blood biochemistry are lacking. For this study, 86 chimango caracaras were captured and studied in Mar del Plata and neighboring areas (Buenos Aires, Argentina) during winter (April-July) in 2018 and 2019. This is the first study to present RIs for 33 blood parameters in a large number of free-living chimango caracaras during the nonbreeding season. In addition, the variability of blood parameters according to sex and calendar year was analyzed. Overall, values for the studied parameters were similar to those described for other raptor species. There were significant differences between years for absolute monocyte counts, relative eosinophils, monocyte counts, glucose, phosphorus, and alanine aminotransferase. Only the relative count of eosinophils, aspartate aminotransferase, and calcium showed significant differences between the sexes. The values of absolute monocyte counts and the relative count of eosinophils and monocytes, glucose, phosphorus, and alanine aminotransferase were higher in 2019 than in 2018, whereas mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration were higher in 2018. Relative eosinophil counts were higher for males than for females, and aspartate aminotransferase activity and calcium concentration were significantly higher for females than for males. The RIs for hematology and plasma biochemistry from this large number of chimango caracaras is of clinical relevance not only for chimango caracaras under medical care in rehabilitation centers but also in ecological studies aimed to investigate the physiological responses of this species to natural and anthropogenic changes.

Hematological and serum biochemical parameters of the captive long‐legged buzzard ( Buteo rufinus ) in Iran

Background

Although normal haematological and serum biochemical values for both pet and wild birds have been published, little information is available on the haematological and serum biochemical values in long‐legged buzzards (Buteo rufinus).

Objectives

This is the first study that aimed to define reference values of haematological, biochemical parameters, and protein electrophoretic fractions of long‐legged buzzards in Iran.

Methods

Blood samples were collected from 30 clinically healthy adult long‐legged buzzards of both sexes. Hematological, biochemical parameters, and protein electrophoretic fractions were measured. The mean and standard deviations were calculated.

Results

Mean values for red blood cells, packed cell volume, haemoglobin, and white blood cells were 2.72 ± 0.60 ×10⁶/μl, 39.10 ± 3.70%, 13.45 ± 1.30 g/dl, and 3.92 ± 1.39 ×10³/μl, respectively. Mean values for biochemistry parameters were total protein 4.46 ± 1.27 g/dl, albumin 1.78 ± 0.55 g/dl, creatinine 0.54 ± 0.22 mg/dl, uric acid 7.81 ± 2.89 mg/dl, calcium 9.63 ± 2.22 mg/dl, phosphorus 4.31 ± 1.00 mg/dl, glucose 398.87 ± 96.90 mg/dl, blood urea nitrogen 10.46 ± 3.85 mg/dl, alkaline phosphatase 127.01 ± 1.46 IU/L, aspartate aminotransferase 262.22 ± 116.30 IU/L, and alanine aminotransferase 56.63 ± 27.85 IU/L. Mean values for serum protein fractions included pre‐albumin, albumin, α‐1 globulin, α‐2 globulin, β‐ globulin, and ϒ‐globulin was 0.20 ± 0.09, 2.35 ± 0.67, 0.28 ± 0.13, 0.32 ± 0.07, 0.62 ± 0.24, and 0.68 ± 0.53 g/dl, respectively.

Conclusion

The reference data presented in this study can be used as health assessment values for veterinary laboratories and clinicians when developing release criteria for rehabilitated long‐legged buzzards.

The prevalence of Leucocytozoon spp. in nestlings of three wild raptor species including implications on haematological and blood chemistry values

Leucocytozoonosis is a vector-borne infection of birds, caused by members of the haemosporidian genus Leucocytozoon. The clinical presentation may range from asymptomatic to severe disease. Consequences of Leucocytozoon infection on blood profiles remain to be described, especially for different host species in the wild. In the current study, the prevalence of Leucocytozoon infection was determined in wild nestlings of three European raptor species, the common buzzard (Buteo buteo, n = 464), red kite (Milvus milvus, n = 46) and northern goshawk (Accipiter gentilis, n = 18). Among 528 nestlings, 51.9% (n = 274) were infected with Leucocytozoon spp., whereby the highest prevalence was found in common buzzards (54.9%), followed by red kites (32.6%) and northern goshawks (22.2%). For a subset of 87 individuals (50 common buzzards, 29 red kites, 8 northern goshawks), a detailed analysis of differential leukocyte counts and several blood chemistry parameters in response to infection was conducted: AP (alkaline phosphatase), AST (aspartate aminotransferase), GLDH (glutamate dehydrogenase), LDH (lactate dehydrogenase), GGT (gamma glutamyl transferase), CK (creatine kinase), BuChE (butyrylcholinesterase), BA (bile acids), ALB (albumin) and TP (total protein). Even though in the physiological range, infected nestlings displayed significantly increased levels of heterophils, aspartate aminotransferase, lactate dehydrogenase, bile acids and butyrylcholinesterase, but decreased lymphocyte and monocyte values compared to uninfected ones. Furthermore, significant species differences with regard to blood parameters, but no sex differences were found. Overall, obtained results show a high prevalence, but a low pathogenicity of Leucocytozoon spp. in wild raptor chicks, presumably resulting from coevolutionary adaptation, but show signatures of infection in the haematological and blood chemistry profiles.

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Leucocytozoon prevalence in nestlings of three wild raptor species was 52%.

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Common buzzards (Buteo buteo) showed the highest prevalence (55%).

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Examined blood parameter values varied with species, age and infection status.

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Leucocytozoon infections were associated with increased AST and BuChE.

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Leucocytozoon infections in Accipitridae nestlings seem to be of minor pathogenicity.

Molecular detection and phylogenetic relationship of Haemosporida parasites in free-ranging wild raptors from Brazil

The order Haemosporida is widely distributed parasitizing members of the Aves class. In birds of prey, infection with Plasmodium spp. parasites varies from an apathogenic form to a clinical syndrome. However, studies on Haemosporida in raptors from the neotropical region are scarce. The aim of this study was to investigate natural infection by Plasmodium spp., Haemoproteus spp. and Leucocytozoon spp. in free-ranging wild raptors from southern Brazil. For this, we sampled 206 individuals of 21 species: 94 live-trapped Southern Caracaras (Caracara plancus) and 112 raptors from other species that were brought to rehabilitation centers. The presence of infection was investigated using a nested-PCR for Haemosporida performed on blood samples. Overall, 56 out of 206 birds were positive for Plasmodium spp./Haemoproteus spp. Twenty-two percent (21/94) of the C. plancus samples were positive. Of the 112 wild raptors rescued, 31% (35/112) of those belonging to 15 other species tested positive. No sample was positive for Leucocytozoon spp. Herein, we demonstrated nine lineages of Haemosporidian parasites (eight Plasmodium sp. and one Haemoproteus sp.) in free-living species of Brazilian birds of prey, being six of them potential novel lineages. It suggests that information currently available on South-American haemosporidian from these birds greatly underestimate the potential lineage diversity in this region.

More massive but potentially less healthy: black vultures feeding in rubbish dumps differed in clinical and biochemical parameters with wild feeding birds

Background

Organic waste is one of the most important anthropogenic food subsidies used by different species. However, there is little information about the health impact that rubbish dumps produce on species foraging in these sites.

Methods

We studied the effect that rubbish dumps produce on the health of a scavenging bird from the Americas, the black vulture (Coragyps atratus). We sampled and studied clinical and biochemical parameters in 94 adult black vultures from two different sites in North Western Patagonia, a rubbish dump and the wild steppe.

Results

We found differences in clinical and biochemical parameters between sites. Body mass was greater in individuals from the dump, whereas in the steppe there were more individuals clinically dehydrated. Biochemical parameters such as uric acid, calcium, alkaline phosphatase, glycaemia, globulins and haematocrit had higher values in individuals using the dump than in individuals from the steppe. Other biochemical parameters such as aspartate aminotransferase, alanine aminotransferase, creatine phosphokinase and urea were higher in individuals from the steppe than in individuals from the dump.

Discussion

Foraging in organic waste could be considered beneficial for black vultures because they increase body mass and parameters associated to nutritional status like calcium and haematocrit. However, foraging in dumps can also affect their health status due to nutritional problems, potential kidney damage or infections that are signalled by the higher values of glycaemia, uric acid and globulins found in individuals from the dump. Our results highlight the contrasting effects that rubbish dumps may produce on wildlife health. They are relevant to different species using these sites, and are also an additional instrument for managing waste.

Synthesis, docking and biological activities of novel hybrids celecoxib and anthraquinone analogs as potent cytotoxic agents

Herein, novel hybrid compounds of celecoxib and 2-aminoanthraquinone derivatives have been synthesized using condensation reactions of celecoxib with 2-aminoanthraquinone derivatives or 2-aminoanthraquinon with celecoxib derivatives. Celecoxib was reacted with different acid chlorides, 2-chloroethylisocyanate and bis (2-chloroethyl) amine hydrochloride. These intermediates were then reacted with 2-aminoanthraquinone. Also the same different acid chlorides and 2-chloroethylisocyanate were reacted with 2-aminoanthraquinone and the resulting intermediates were reacted with celecoxib to give isomers for the previous compounds. The antitumor activities against hepatic carcinoma tumor cell line (HEPG2) have been investigated in vitro, and all these compounds showed promising activities, especially compound 3c, 7, and 12. Flexible docking studies involving AutoDock 4.2 was investigated to identify the potential binding affinities and the mode of interaction of the hybrid compounds into two protein tyrosine kinases namely, SRC (Pp60v-src) and platelet-derived growth factor receptor, PDGFR (c-Kit). The compounds in this study have a preferential affinity for the c-Kit PDGFR PTK over the non-receptor tyrosine kinase SRC (Pp60v-src).

Hematologic and biochemical reference intervals for wild osprey nestlings (Pandion haliaetus)

A retrospective study of blood samples from 95 osprey (Pandion haliaetus) nestlings from Scotland and England, collected opportunistically over a 10-yr period, was performed to determine hematologic and plasma biochemistry reference intervals. The age of the sampled nestlings was estimated to be between 4 and 8 wk. Ninety-five percent reference intervals were determined for all hematologic and biochemical variables using parametric and nonparametric methods as appropriate. No blood parasites were detected. This is the first published study providing baseline reference data for osprey nestlings, and it is hoped the data will be of use to wildlife veterinarians and biologists in assessing the health of this species.

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.

Hematologic parameters in raptor species in a rehabilitation setting before release

To be considered for release, raptors undergoing rehabilitation must have recovered from their initial injury in addition to being clinically healthy. For that purpose, a good understanding of reference hematologic values is important in determining release criteria for raptors in a rehabilitation setting. In this study, retrospective data were tabulated from clinically normal birds within 10 days of release from a rehabilitation facility. Hematologic values were compiled from 71 red-tailed hawks (Buteo jamaicensis), 54 Eastern screech owls (Megascops asio), 31 Cooper's hawks (Accipiter cooperii), 30 great-horned owls (Bubo virginianus), 28 barred owls (Strix varia), 16 bald eagles (Haliaeetus leucocephalus), and 12 broad-winged hawks (Buteo platypterus). Parameters collected included a white blood cell count and differential, hematocrit, and total protein concentration. Comparisons were made among species and among previously published reports of reference hematologic values in free-ranging birds or permanently captive birds. This is the first published report of reference values for Eastern screech owls, barred owls, and broad-winged hawks; and the first prerelease reference values for all species undergoing rehabilitation. These data can be used as a reference when developing release criteria for rehabilitated raptors.

Toxic effects of dietary methylmercury on immune function and hematology in American kestrels (Falco sparverius)

Fifty-nine adult male American kestrels (Falco sparverius) were assigned to one of three diet formulations including 0 (control), 0.6, and 3.9 µg/g (dry wt) methylmercury (MeHg). Kestrels received their diets daily for 13 weeks to assess the effects of dietary MeHg on immunocompetence. Immunotoxic endpoints included assessment of cell-mediated immunity (CMI) using the phytohemagglutinin (PHA) skin-swelling assay and primary and secondary antibody-mediated immune responses (IR) via the sheep red blood cell (SRBC) hemagglutination assay. Select hematology and histology parameters were evaluated to corroborate the results of functional assays and to assess immunosuppression of T and B cell-dependent components in spleen tissue. Kestrels in the 0.6 and 3.9 µg/g MeHg groups exhibited suppression of CMI, including lower PHA stimulation indexes (p = 0.019) and a 42 to 45% depletion of T cell-dependent splenic lymphoid tissue (p = 0.006). Kestrels in the 0.6 µg/g group exhibited suppression of the primary IR to SRBCs (p = 0.014). MeHg did not have a noticeable effect on the secondary IR (p = 0.166). Elevation of absolute heterophil counts (p < 0.001), the heterophil to lymphocyte ratio (p < 0.001), and total white blood cell counts (p = 0.003) was apparent in the 3.9 µg/g group at week 12. Heterophilia, or the excess of heterophils in peripheral blood above normal ranges, was apparent in seven of 17 (41%) kestrels in the 3.9 µg/g group and was indicative of an acute inflammatory response or physiological stress. This study revealed that adult kestrels were more sensitive to immunotoxic effects of MeHg at environmentally relevant dietary concentrations than they were to reproductive effects as previously reported.

Quantitative ultrasound, magnetic resonance imaging, and histologic image analysis of hepatic iron accumulation in pigeons (Columbia livia)

Iron overload was induced by iron dextran i.v. in clinically healthy adult pigeons, Columbia livia, (n = 8). Hemosiderosis was induced in all treated birds. Two control pigeons received no iron injections. Pigeons did not show clinical signs of iron overload during the 6-wk study. Ultrasound examination of the liver in the pigeons receiving iron dextran was performed on days 0, 13, 28, and 42. No ultrasound images were collected on the control pigeons. Magnetic resonance imaging was performed on days 0, 13, 28, and 42 on all study pigeons and imaging sequences were collected in three different imaging formats: T1, T2, and gradient-recalled echo (GRE). Surgical liver biopsies were performed on pigeons receiving iron dextran on days 2, 16, and 45 (at necropsy). A single liver sample was collected at necropsy from the control birds. Histologic examination, quantitative image analysis, and tissue iron analysis by thin-layer chromatography were performed on each liver sample and compared to the imaging studies. Although hemosiderosis was confirmed histologically in each experimental pigeon, no significant change in pixel intensity of the ultrasound images was seen at any point in the study. Signal intensity, in all magnetic resonance imaging formats, significantly decreased in a linear fashion as the accumulation of iron increased.

Raptor medicine: an approach to wild, falconry, and educational birds of prey

A veterinarian receiving birds of prey (raptors) will often be presented with wild, educational, or falconry raptors. Raptors trained for the sport of falconry and educational raptors are handled in a precise manner, often differently from the wild raptors. It is imperative for veterinarians treating raptors to be familiar with the equipment and terminology used by the individuals caring for these birds. The hospital staff must also be educated to handle the raptors properly, both wild and tame, because differences do exist between the approaches. Raptor medicine requires a thorough diagnostic work-up and aggressive therapeutic plan to help ensure a fast and complete recovery.

Clinical chemistry of companion avian species: a review

Birds have evolved alternate physiologic strategies to contend with dehydration, starvation, malnutrition, and reproduction. Basic anatomic and functional differences between birds and mammals impact clinical chemistry values and their evaluation. Interpretation of the results of standard biochemical analyses, including BUN, alanine aminotransferase, aspartate aminotransferase, creatine kinase, gamma glutamyltransferase, bilirubin, ammonia, alkaline phosphatase, cholesterol, bile acids, glucose, albumin, globulins, calcium, phosphorus, prealbumin (transthyretin), fibrinogen, iron, and ferritin, is reviewed and discussed in relation to these physiological differences. The use and interpretation of alternative analytes appropriate for avian species, such as uric acid, biliverdin, glutamate dehydrogenase, and galactose clearance, also are reviewed. Normal avian urine and appropriate use of urinalysis, an integral part of laboratory diagnosis in mammalian species that frequently is omitted from avian diagnostic protocols, is discussed.