Hematological, protein electrophoresis and cholinesterase values of free-living nestling peregrine falcons in Spain

Protein Electrophoresis of Serum and Heparinized Plasma in the Common Mynah (Acridotheres tristis)

Although serum protein electrophoresis is a diagnostic tool available through many veterinary laboratories, there currently are no reference intervals for protein fractions in healthy common mynahs (Acridotheres tristis). Therefore, electrophoretic patterns of proteins in serum and heparinized plasma of the common mynah were evaluated. Blood specimens were collected from 55 healthy adult common mynahs of unknown age (26 males and 29 females). The serum total protein and protein fractions were measured using the biuret method followed by cellulose acetate electrophoresis (CAE). The serum level of albumin was compared with bromocresol green (BCG) dye-binding and CAE methods. Four protein fractions, including albumin and α, β, and γ globulins, were recorded in the electrophoretogram of serum specimens. Sex appeared to have no significant effect on the measured parameters. The serum BCG albumin fraction was significantly higher than the CAE albumin fraction (P = .01). Also, the comparison of total protein and protein fractions in serum and plasma specimens of 25 of the 55 birds sampled showed that total protein (Cohen index d = 0.66, P = .03), gamma globulin (d = 1.13, P = .00), and total globulin (d = 0.67, P = .00) in plasma samples were significantly higher than those in serum samples. The results of this study provide the specific reference intervals for total protein and protein fractions in common mynahs, which are essential for proper interpretation of laboratory results and also revealed that the albumin measurement by the BCG method yields unreliable results in common mynahs.

The Influence of Biological Factors on Haematological Values in Wild Marsh Harrier (Circus aeruginosus) Nestlings

Simple Summary

Haematological examination can be used to address the health state of birds. The present study aimed to investigate how hatching order, brood size, and nest initiation date influence the haemoglobin level, red blood cell count, white blood cell count, and glucose level in the blood of raptor nestlings in which brood reduction occurs during nestling rearing. Blood samples were collected to assess the health status of wild marsh harrier nestlings in the agricultural landscape of eastern Poland. Statistical analyses revealed that hatching order, but not brood size or nest initiation date, had an impact on the haematological data of nestlings. Hatching order affected these data in that haemoglobin levels and red blood cell counts gradually decreased, whereas glucose levels and white blood cell counts increased, from the first- to the last-hatched nestlings. The poor condition of the youngest nestlings reflected in these indices may increase the likelihood of their perishing, and consequently, of brood reduction.

Abstract

Marsh harrier (Circus aeruginosus) is a species with obligatory cainism, in which hatching asynchrony creates a pronounced size hierarchy in nestlings. The size-related competitive advantage of older nestlings means that they tend to dominate the younger ones, and brood reduction occurs in most nests. The aim of the study was to reference values and carry out a haematological examination in order to evaluate the physiological status and health of nestlings with respect to hatching order, brood size, and nest initiation date. To do so, we examined 19 nests with a total of 58 nestlings from a free-living population of this species located in fishpond complexes in the agricultural landscape of eastern Poland. Repeated blood samples (118 in all) were collected from nestlings. The following parameters were measured using fresh full blood: red blood cell count (RBC), haemoglobin level (Hb), white blood cell count (WBC), and plasma glucose level (Glu). The data were analysed using generalized linear mixed models and linear mixed models ((G)LMM). The study revealed that hatching order, but not brood size or nest initiation date, affected the physical condition of marsh harrier nestlings. Hb levels and RBC counts gradually decreased, whereas Glu levels and WBC counts increased from the first- to the last-hatched nestlings. This result points to the generally poorer condition of the youngest nestlings compared with their older siblings. The poor physiological condition of the youngest nestlings may consequently increase the likelihood of their perishing, and hence, of brood reduction.

Assessing the seasonal and intrinsic variability of neurotoxic and cyto-genotoxic biomarkers in blood of free-living Eleonoras' falcons

In the present study we investigated seasonal and intrinsic variability of neurotoxic and cyto-genotoxic biomarkers in blood plasma and erythrocytes of free-living Eleonoras' falcons, captured during the pre-breeding (May of 2017 and 2018) and breeding period (September of 2017) on the Antikythira Island (Greece). Specifically, blood samples of captured birds were prepared for the determination of cholinesterase (ChEs, i.e. acetylcholinesterase/AChE and butyrylcholinesterase/ BChE) activity, as well as the formation of nuclear (i.e. the formation of micronuclei into the cells/MN, binucleated cells/BN and others), and cellular/cytoplasmic (i.e. echinocytes/EC, acanthocytes/AC and notched cells/NC) abnormalities in blood plasma and erythrocytes, respectively. Our results indicated that birds sampled in late May had higher ChE and BChE activity levels, as well as higher frequency of total nuclear abnormalities. The latter were also higher in second calendar year (2cy) birds. Cellular/cytoplasmic abnormalities were less frequent in falcons having better body condition, sampled in late May, as well as in light-morph falcons. The observed ChEs activities, as well as nuclear and cellular/cytoplasmic abnormalities revealed that Eleonora's falcons are likely to be exposed to chemical agents with neurotoxic and cyto-genotoxic potential year round, while different aspects of their biology and ecology, such as their reproductive and nutritional status, could mediate their levels. Although we encourage more sampling campaigns to verify the identified seasonal and intrinsic sources of variation in biomarkers tested, the current study enriches the existing knowledge about their usefulness in the environmental monitoring and risk assessment of migratory birds, like Eleonoras' falcon.

Advances in Exotic Animal Clinical Pathology

Over the last 10 years, exotic animal clinical pathology has been evolving, improving health assessment in avian, mammal, fish, reptile, and amphibian patients. These advances are reviewed in this article. Species-specific reference intervals for blood parameters are becoming more available (eg, for ionized calcium, endocrine panels, and vitamin D plasmatic concentrations). In addition, new technologies are being developed to facilitate targeted metabolite detection and result acquisition by veterinarians. Novel techniques, biomarkers, and clinical changes related to disease have been described in avian, mammal, fish, reptile and amphibian species. The use of mobile applications may also be helpful.

The influence of natural variation and organohalogenated contaminants on physiological parameters in white-tailed eagle (Haliaeetus albicilla) nestlings from Norway

Environmental exposure to organohalogenated contaminants (OHCs), even at low concentrations, may cause detrimental effects on the development and health of wild birds. The present study investigated if environmental exposure to OHCs may influence the variation of multiple physiological parameters in Norwegian white-tailed eagle (Haliaeetus albicilla) nestlings. Plasma and feather samples were obtained from 70 nestlings at two archipelagos in Norway in 2015 and 2016. The selected physiological parameters were plasma concentrations of thyroid hormones (thyroxine, T4 and triiodothyronine, T3), plasma proteins (prealbumin, albumin, α₁-, α₂-, β- and γ-globulins) and selected blood clinical chemical parameters (BCCPs) associated with liver and kidney functioning. Feather concentrations of corticosterone (CORT_f) were also included to investigate the overall stress level of the nestlings. Concentrations of all studied physiological parameters were within the ranges of those found in other species of free-living birds of prey nestlings and indicated that the white-tailed eagle nestlings were in good health. Our statistical models indicated that perfluoroalkyl substances (PFASs) and legacy OHCs, such as polychlorinated biphenyls, organochlorinated pesticides and polybrominated diphenyl ethers, influenced only a minor fraction of the variation of plasma thyroid hormones, prealbumin and CORT_f (5-15%), and partly explained the selected BCCPs (<26%). Most of the variation in each studied physiological parameter was explained by variation between nests, which is most likely due to natural physiological variation of nestlings in these nests. This indicates the importance of accounting for between nest variation in future studies. In the present nestlings, OHC concentrations were relatively low and seem to have played a secondary role compared to natural variation concerning the variation of physiological parameters. However, our study also indicates a potential for OHC-induced effects on thyroid hormones, CORT_f, prealbumin and BCCPs, which could be of concern in birds exposed to higher OHC concentrations than the present white-tailed eagle nestlings.

Protein electrophoresis in Andean condors (Vultur gryphus): Reference values and differences between wild and rehabilitating individuals

The study of wildlife health greatly contributes to understanding population dynamics and detecting conservation threats. The determination of the different fractions of plasma proteins (proteinogram) is an important laboratory tool to study wildlife health. The aim of this study was to characterize protein electrophoresis in wild Andean condors (Vultur gryphus) from north-western Patagonia and to evaluate differences according to age and sex classes. Once reference values of wild, apparently healthy individuals, were established, we compared these values to those of individuals received at the Buenos Aires Zoo in Argentina for rehabilitation due to various health problems. Reference proteinograms from wild Andean condors differed only in the α 1 and β 2-fractions between sex categories. Males showed higher concentrations of these protein fractions than females. We found clear differences between wild birds and rehabilitating individuals. Total proteins, globulins, α 1-globulins, total α-globulins, β 2-globulins, total β-globulins, and γ-globulins were significantly higher in rehabilitating than in wild individuals, whereas albumin, α 2, and β1-globulins were similar between these groups. The albumin/globulin ratio, as a general indicator of health, was significantly lower in rehabilitating than in wild individuals. The results indicate the effects on different protein fractions of pathologic processes occurring in individuals undergoing rehabilitation. Our results provide useful insights, contributing to improving diagnoses and prognoses in this species. This information may also be useful to assess the health status of Andean condors in studies of wild populations and for comparisons with other bird species.

Plasma protein fractions in free-living white-tailed eagle (Haliaeetus albicilla) nestlings from Norway

BACKGROUND

Capillary electrophoresis of plasma proteins has shown great potential as a complementary diagnostic tool for avian species. However, reference intervals for plasma proteins are sparse or lacking for several free-living avian species. The current study reports electrophoretic patterns and concentrations of plasma proteins determined for 70 free-living white-tailed eagle (Haliaeetus albicilla) nestlings from two locations in Norway (Steigen and Smøla) in order to establish reference values for this subpopulation using capillary electrophoresis. The nestlings were between 44 and 87 days of age, and the plasma protein concentrations were investigated for age, sex, year (2015 and 2016) and location differences. To our knowledge, this is the first report of reference intervals of plasma proteins analysed by capillary electrophoresis in free-living white-tailed eagle nestlings.

RESULTS

The plasma protein concentrations (% of total protein, mean ± SE) were determined for prealbumin (13.7%, 4.34 ± 0.15 g/L), albumin (46.7%, 14.81 ± 0.24 g/L), α₁-globulin (2.4%, 0.74 ± 0.03 g/L), α₂-globulin (11.7%, 3.72 ± 0.06 g/L), β-globulin (15.9%, 5.06 ± 0.08 g/L) and γ-globulin (9.6%, 3.05 ± 0.09 g/L). Significant differences were found between the two locations for prealbumin, α₂- and γ-globulins. No significant differences were found between the two sampling years or sexes, and no effect of age was found for any of the plasma proteins. However, prealbumin levels were several folds higher than previously reported from adults of closely related birds of prey species. There were no other studies on capillary electrophoresis of nestling plasma available for comparison.

CONCLUSION

Significant differences were found between sampling locations for prealbumin, α₂- and γ-globulins, which may indicate differences in inflammatory or infectious status between nestlings at the two locations. Sampling year, sex or age had no significant effect on the plasma protein concentrations. These results provide novel data on plasma protein concentrations by capillary electrophoresis and may be useful for evaluation of health status in free-living white-tailed eagle nestlings.

Plasma protein electrophoresis as a prognostic indicator in Aspergillus species-infected Gentoo penguins (Pygoscelis papua papua)

BACKGROUND

Avian aspergillosis presents a significant threat to captive penguin populations. Currently, a lack of objective prognostic factors limits disease staging, objective reassessment throughout treatment, comparative evaluation of treatment regimes, and appropriate timing of euthanasia.

OBJECTIVE

The study objective was to investigate absolute and relative plasma protein fractions by agarose gel electrophoresis (EPH) as predictors of survival in Gentoo penguins (Pygoscelis papua papua) under treatment for aspergillosis.

METHODS

One hundred and eighty-three EPH profiles from individual clinical cases were examined retrospectively. Animal survival to 90 days post sampling was established from clinical records; birds either survived (n = 146) or died within 90 days (n = 37), and time to death was recorded.

RESULTS

Fourteen variables showed statistically significant differences (P < .05) between surviving and dying birds. Receiver operating characteristic curve analysis identified total albumin concentration (albumin + prealbumin) and albumin-to-globulin (A:G) ratio as having strongest discriminatory values (95% CI) at 0.788 (0.710-0.866) and 0.784 (0.696-0.871), respectively. Albumin (concentration and percentage of total protein) displayed moderate discriminatory value but additionally a weak positive correlation with time to death (95% CI); r = .353 (0.033-0.608) and .424 (0.116-0.658), respectively.

CONCLUSIONS

Optimized test cutoffs for total albumins, albumin (concentration and percentage of total protein), and A:G ratio achieved moderate sensitivity and specificity, strong negative predictive values, but weak positive predictive values due to a low prevalence of death. Selection of appropriate test cutoff values may provide valuable adjunctive prognostic tools for clinical decision-making when the prognosis is difficult to assess clinically.

STRESS INFLUENCE ON PLASMA PROTEIN ELECTROPHORESIS IN THE RED-BREASTED GOOSE (BRANTA RUFICOLLIS) AND HAWAIIAN GOOSE (BRANTA SANDVICENSIS)

The objective of this study was to evaluate the effects of stress (as measured by total heterophil + eosinophil counts [THECs] and plasma corticosterone [PC] levels) on plasma protein electrophoresis (PPE) in two Anseriform species. Ten red-breasted geese ( Branta ruficollis ) and eight Hawaiian geese (Branta sandvicensis) were received into quarantine at Beauval Zoo and housed together with other Anseriformes. Two days later, all were examined as part of routine quarantine procedures, and blood was collected. THECs were performed using a Malassez hemocytometer after a 1 : 200 dilution with an eosinophil dilution liquid containing phloxine B. PPE, as well as total protein and PC assays, was performed on lithium heparin plasma. Twenty days after arrival, all birds were similarly restrained, examined, and sampled. Pododermatitis lesions were identified on four geese that were excluded from statistical analysis. For each goose, THECs and PC values were sorted by value (lower or higher) independently from the day of sampling. A Wilcoxon signed rank test showed no significant differences between lower and higher values of THECs for any of the PPE fractions. Higher values of corticosterone were associated with higher values of prealbumin, but none of the other fractions were significantly different. A Spearman rank correlation coefficient showed that THECs and PC were not correlated; this suggested differences in kinetics between these stress markers. Results did not show significant alterations of electrophoresis patterns associated with stress as measured with THECs and PC. The results also highlight the complexity of precisely assessing acute and chronic stress in avian species.

Generalized Tetanus in a Gyrfalcon ( Falco rusticolus ) with Pododermatitis

A 2-yr-old male gyrfalcon ( Falco rusticolus ) was presented for severe and generalized muscle spasticity and pododermatitis. The falcon had been treated for pododermatitis over the previous 4 mo. Muscle rigidity and spasms involved the entire bird but were more severe on the right leg. The bird was also tachypneic and hyperthermic at 45 C. While the plantar pododermatitis lesions had healed, there was still a small abscess on the lateral aspect of the right foot. Clinical signs were consistent with tetanus. Several bacteria were isolated from the abscess including Clostridium tetani . The isolate was confirmed to be toxigenic by PCR. Attempts to detect tetanus toxin in the bird's plasma were unsuccessful. The abscess was debrided. The gyrfalcon received equine tetanus antitoxin, intravenous metronidazole, methocarbamol, midazolam, a constant-rate infusion of Fentanyl, active cooling, and supportive care. Inhalant anesthesia with isoflurane was the only treatment that would lower the body temperature and reduce the clinical signs. The gyrfalcon died a few hours after admission. The characteristic clinical signs and isolation of toxigenic C. tetani from a wound were strong supportive evidence for a diagnosis of tetanus. This case constitutes the first reported natural occurrence of tetanus in an avian species. Further information is needed to determine whether gyrfalcons are more susceptible to tetanus than are other avian species and whether pododermatitis lesions may be risk factors.

Vertebral Osteomyelitis and Septic Arthritis Associated With Staphylococcus hyicus in a Juvenile Peregrine Falcon ( Falco peregrinus )

A 6-week-old, parent-reared peregrine falcon ( Falco peregrinus ) was presented with spastic hypertonus of its hind limbs of unknown origin and duration. Radiologic examination revealed smooth periosteal reactions ventrally at thoracic vertebrae 5 to 7. Contrast-enhanced computed tomography identified the swelling as inflammation; antibiotic, antimycotic, anti-inflammatory, and analgesic treatments were initiated, and vitamins and minerals were supplemented. Because the bird's condition did not improve after 10 days, it was euthanatized and submitted for postmortem examination. On histopathologic examination, chronic, active osteomyelitis was diagnosed in thoracic vertebrae 5 to 7, and chronic, active arthritis was present in both the right shoulder and left elbow joints. Staphylococcus hyicus was isolated from these 3 locations, as well as from lungs and liver, indicating a chronic septic staphylococcosis. Although infections with Staphylococcus species are occasional causes of vertebral osteomyelitis in juvenile poultry with active growth plates, it is only sporadically reported in raptors and companion birds. This case report is the first description of the clinical features and diagnostic and pathologic findings in a juvenile peregrine falcon with hematogenous osteomyelitis and arthritis associated with septicemia caused by S hyicus.

Investigating endocrine and physiological parameters of captive American kestrels exposed by diet to selected organophosphate flame retardants

Organophosphate triesters are high production volume additive flame retardants (OPFRs) and plasticizers. Shown to accumulate in abiotic and biotic environmental compartments, little is known about the risks they pose. Captive adult male American kestrels (Falco sparverius) were fed the same dose (22 ng OPFR/g kestrel/d) daily (21 d) of tris(2-butoxyethyl) phosphate (TBOEP), tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP), or tris(1,2-dichloro-2-propyl) phosphate (TDCIPP). Concentrations were undetected in tissues (renal, hepatic), suggesting rapid metabolism. There were no changes in glutathione status, indicators of hepatic oxidative status, or the cholinergic system (i.e., cerebrum, plasma cholinesterases; cerebrum muscarinic, nicotinic receptors). Modest changes occurred in hepatocyte integrity and function (clinical chemistry). Significant effects on plasma free triiodothyronine (FT3) concentrations occurred with exposure to TBOEP, TCEP, TCIPP, and TDCIPP; TBOEP and TCEP had additional overall effects on free thyroxine (FT4), whereas TDCIPP also influenced total thyroxine (TT4). Relative increases (32%-96%) in circulating FT3, TT3, FT4, and/or TT4 were variable with each OPFR at 7 d exposure, but limited thereafter, which was likely maintained through decreased thyroid gland activity and increased hepatic deiodinase activity. The observed physiological and endocrine effects occurred at environmentally relevant concentrations and suggest parent OPFRs or metabolites may have been present despite rapid degradation.

Characterization of plasma cholinesterase from the White stork (Ciconia ciconia) and its in vitro inhibition by anticholinesterase pesticides

Blood plasma cholinesterase (ChE) activity is a sensitive biomarker of exposure to organophosphorus (OP) and carbamate (CB) insecticides in vertebrates. Several studies indicate that more than one ChE form may be present in blood of birds. In this study the predominant ChE activity (acetylcholinesterase - AChE- or butyrylcholinesterase - BChE-), the range of ChE activity as well as ChE age-dependent changes in non-exposed individuals of White stork (Ciconia ciconia) have been established. The in vitro sensitivity of ChE to OP and CB insecticides such as paraoxon-methyl, carbofuran and carbaryl was also investigated. Plasma ChE was characterised using three substrates (acetylthiocholine iodide, propionylthiocholine iodide, and S-butyrylthiocholine iodide) and three ChE inhibitors (eserine sulphate, BW284C51 and iso-OMPA). The results indicated that propionylthiocholine was the preferred substrate by plasma cholinesterase followed by acetylcholine and butyrylcholine and the predominant enzymatic activity in plasma of White storks was BChE. Normal plasma BChE activity in White stork was 0.32±0.01μmol/min/ml for adults and 0.28±0.03μmol/min/ml for juveniles. So, the age had no significant effect on the range of BChE activity. The study on the in vitro inhibitory potential of tested anticholinesterase pesticides on plasma ChE activity revealed that paraoxon-methyl is the most potent inhibitor followed by carbofuran and finally by carbaryl. The percentage of in vitro plasma ChE inhibition was observed to be similar between adults and juveniles.

Plasma protein electrophoresis in birds: comparison of a semiautomated agarose gel system with an automated capillary system

Plasma agarose gel electrophoresis (AGE) is recognized as a very reliable diagnostic tool in avian medicine. Within the last 10 years, new electrophoresis techniques such as capillary zone electrophoresis (CZE) have emerged in human laboratory medicine but have never been investigated in birds. To investigate the use of CZE in birds and to compare it with AGE, plasma samples from 30 roosters (Gallus gallus), 20 black kites (Milvus migrans), and 10 racing pigeons (Columba livia) were analyzed by both AGE and CZE. For the 3 species studied, values determined by AGE and CZE were well correlated for albumin and beta and gamma fractions whereas other values differed significantly. Values for alpha-3 fraction in the rooster, alpha-1 fraction in the black kite, and alpha fractions in the pigeon obtained by AGE were very well correlated with the prealbumin fraction values obtained by CZE. Repeatability and reproducibility appeared higher with CZE than with AGE. Although the interpretation of CZE electrophoresis patterns seems to produce results similar to those obtained with AGE, some proteins present in the alpha fraction measured with AGE migrated to the prealbumin fraction found with CZE. Although CZE requires the use of specific reference intervals and a much higher sample volume, this method has many advantages when compared with AGE, including better repeatability and reproducibility and higher analysis output.

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.

Hematologic values in healthy gyr x peregrine falcons (Falco rusticolus x Falco peregrinus)

The gyr x peregrine (Falco rusticolus x Falco peregrinus) hybrid is the most common falcon treated at Nad Al Shiba Veterinary Hospital in Dubai. To improve the health assessment of individual birds in the population treated at this hospital, we established reference ranges of hematologic values for this hybrid falcon. The hematologic parameters of 96 gyr x peregrine falcons were assessed and compared with other published values for the same hybrid falcon.

Health assessment of Black-crowned Night-herons (Nycticorax nycticorax) of the New York Harbor estuary

Blood samples from 145 Black-crowned Night-heron (Nycticorax nycticorax, BCNH) chicks (mean age 3 weeks) were taken from four island colonies (Goose (2004), Canarsie Pol (2005), Hoffman (2004 and 2005) and North Brother (2004 and 2005)) in New York Harbor in 2004 and 2005 to establish baseline health reference ranges for this species and to compare health indices of birds reared on different islands. Packed cell volume (PCV) and total solids (TS) did not differ among islands in either year. Herons raised on Hoffman Island in 2004 had lower white blood cell count (WBC), and higher activities of creatine phosphokinase (CPK), lactate dehydrogenase (LDH), aspartate amino transferase (AST), higher concentrations of potassium (K) and phosphorous (PHOS) and lower liver derived proteins (TP, prealbumin, albumin, alpha 1 globulins, alpha 2 globulins, beta globulins and gamma globulins) compared to herons from Goose and North Brother Islands. These changes suggest compromised health in chicks reared on Hoffman Island in 2004. On Hoffman in 2005, these biochemical analytes did not differ from concentrations and enzyme activities measured from birds on other islands. Although no single etiology can explain these extensive changes, it is likely that exposure to contaminants at foraging sites used by birds nesting on Hoffman and/or changes in prey availability and abundance causing birds to forage in different locations between years, led to differences measured in blood-based health indices. Avian health assessments coupled with foraging ecology serve as an excellent method for evaluating ecosystem health of the New York Harbor estuary system.

Assessment of the reliability of plasma electrophoresis in birds

OBJECTIVE

To determine the reliability of plasma electrophoresis (EPH) in psittacine birds.

ANIMALS

93 psittacine birds.

PROCEDURE

Jugular venipuncture was performed on 93 awake psittacine birds. The plasma was centrifuged, separated, aliquoted into duplicate samples, frozen, and sent to 2 commercial laboratories that routinely perform avian EPH. Samples from 51 birds were sent to laboratory A, and samples from 42 birds were sent to laboratory B. The reliability of EPH results within each laboratory was assessed, but not between laboratories. To determine the reliability (agreement between duplicate samples) of total protein, albumin, prealbumin, alpha1-, alpha2-, beta-, and gamma-globulin concentrations, the intraclass correlation coefficient (r(i)) was calculated.

RESULTS

Both laboratories had excellent agreement between samples for measurement of total protein concentration and only good agreement for albumin concentration. Except for the prealbumin concentration measured at laboratory B, both laboratories had poor agreement for all other values of the EPH.

CONCLUSIONS AND CLINICAL RELEVANCE

These data indicate that plasma EPH for measuring prealbumin, alpha1-, alpha2-, beta-, and gamma-globulin concentrations may not be a reliable tool for assessing avian health. Small amounts of these proteins in birds plus human variation in reading the EPH curves may lead to variable results. Avian veterinarians should cautiously interpret results from plasma EPH assays for these protein fractions.