Protein electrophoresis as a diagnostic and prognostic tool in raptor medicine

Diagnostic value of serum amyloid A in differentiating the inflammatory disorders in wild birds

Rescued wild birds have very high rates of inflammatory diseases; however, there have been limitations in assessing them sensitively. Few studies have examined acute-phase proteins in wild birds. In this study, serum amyloid A (SAA) was evaluated as an inflammatory indicator along with traditional indices such as white blood cell count, albumin, and albumin/globulin ratio. In total, 291 samples from 139 birds of six avian species were analyzed. All samples were divided into four groups (severe, moderate, mild injuries, and clinically healthy) based on clinical examinations and evaluated by group. SAA levels were measured using an anti-chicken SAA ELISA kit and compared with leukocyte counts, albumin concentrations, and albumin/globulin ratios. Differences among groups were evaluated using the Kruskal-Wallis test, followed by a post hoc test using Dunn's multiple comparisons with SPSS V27. Statistical significance was set at a value of p of <0.05. The median concentration and interquartile range (ng/mL) of SAA in each group were 78.10 ng/mL (50.71-109.30), 31.15 ng/mL (19.85-49.24), 9.68 ng/mL (4.71-22.06), and 3.10 ng/mL (1.50-6.00). We observed a significant difference in the mean levels between the groups (p < 0.001), with the same results observed across species. All four indices showed significant differences in mean values between the groups (p < 0.001). In addition, SAA showed rapid changes in periodically collected samples, reflecting either a positive treatment response or the onset of subclinical diseases. SAA can be used to detect inflammatory conditions and asymptomatic disease in wild birds and is helpful in accurately identifying current health status, which is essential for successful treatment and release.

Comparison of agarose gel and capillary zone electrophoresis methods with preliminary reference interval generation using capillary zone electrophoresis in bald eagles (Haliaeetus leucocephalus)

BACKGROUND

Electrophoresis can be used to aid in the diagnosis of different diseases in avian species. Capillary zone electrophoresis (CZE) is an automated method that is proposed to be superior to the dye methods used in agarose gel electrophoresis (AGE). However, reference intervals (RIs) for CZE in avian species and comparison studies between electrophoretic methods are lacking.

OBJECTIVES

The goals of the current study were to compare AGE and CZE methods and determine reference intervals for CZE using plasma from bald eagles (Haliaeetus leucocephalus).

METHODS

Heparinized plasma samples from 44 bald eagles (mean age 18.7 years) under managed care were examined by AGE and CZE. Method comparison analyses were completed, as well as the generation of preliminary RIs using the CZE method and ASVCP guidelines.

RESULTS

Passing-Bablok regression and Bland-Altman plots demonstrate that these methods are not equivalent. All fractions were significantly correlated between the methods except for alpha 1 globulin. Inter-assay and intra-assay CVs for CZE were lower or comparable to AGE and ranged from 2.4% to 15.4%, and 0.8% to 8.3%, respectively. CZE resolved more fractions than AGE with two fractions observed in the beta and gamma region vs one for AGE in each region.

CONCLUSIONS

CZE provided improved resolution and reproducibility for the quantitation of protein fractions in the bald eagle. Although most fraction results correlated with AGE, these methods were judged as not equivalent, necessitating method-specific Rls. Reference intervals generated from a limited number of mostly aged individuals under managed care should be considered preliminary; additional studies will aid in the production of more robust intervals.

Avian Inflammatory Markers

Inflammation represents a fundamental response to diverse diseases ranging from trauma and infection to immune-mediated disease and neoplasia. As such, inflammation can be a nonspecific finding but is valuable as an indicator of pathology that can itself lead to disease if left unchecked. This article focuses on inflammatory biomarkers that are available and clinically useful in avian species. Inflammatory biomarkers are identified via evaluation of whole blood and plasma and can be divided into acute and chronic, with varying degrees of specificity and sensitivity. Evaluation of multiple biomarkers may be necessary to identify subclinical disease.

Challenges to establish the diagnosis of aspergillosis in non-laboratory animals: looking for alternatives in veterinary medicine and demonstration of feasibility through two concrete examples in penguins and dolphins

Aspergillosis remains difficult to diagnose in animals. Laboratory-based assays are far less developed than those for human medicine, and only few studies have been completed to validate their utility in routine veterinary diagnostics. To overcome the current limitations, veterinarians and researchers have to propose alternative methods including extrapolating from human diagnostic tools and using innovative technology. In the present overview, two specific examples were complementarily addressed in penguins and dolphins to illustrate how is challenging the diagnosis of aspergillosis in animals. Specific focus will be made on the novel application of simple testing in blood based on serological assays or protein electrophoresis and on the new information garnered from metabolomics/proteomics to discover potential new biomarkers. In conclusion, while the diagnostic approach of aspergillosis in veterinary medicine cannot be directly taken from options developed for human medicine, it can certainly serve as inspiration.

Protein electrophoresis of non-traditional species: A review

EPH has been demonstrated to be a useful tool in companion animals while providing an opportunity to characterize globulinemias, including paraproteinemia. In EPH of non-traditional species, these same applications are important, but the primary use is to gauge the acute-phase and humoral immune responses. This includes the valid quantitation of albumin as well as the examination of fractions reflective of increases in acute-phase reactants and immunoglobulins. Agarose gel EPH and, more recently, capillary zone EPH have been applied to samples from these species. Performing these analyses provides special challenges in the placement of fraction delimits, generation of RIs, and interpretation of results. Recommended as part of routine bloodwork, EPH can also provide key results that are helpful in clinical and field-based health assessments as well as in prognostication.

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.

Comparison of Capillary Zone Electrophoresis in Greater Flamingos (Phoenicopterus roseus) and American Flamingos (Phoenicopterus ruber)

Electrophoresis can be used to aid in the diagnosis of infectious diseases (eg, aspergillosis) in avian species. Reference intervals for blood plasma proteins of 2 different flamingo species (Phoenicopterus roseus and Phoenicopterus ruber) and their hybrids were calculated by capillary zone electrophoresis (CZE) and differences between these species, sexes, and age groups were evaluated. Lithium-heparinized plasma samples from 111 animals from a zoological collection were analyzed by CZE and statistically evaluated. Differences were only found between greater and American flamingos (P = .003) and between greater flamingos and hybrids (P = .001) in the γ-globulin fraction. Male greater flamingos showed significantly higher α-globulins (P = .022) and females higher total albumin by CZE (P = .037). In American flamingos, the percent total albumin (P = .017), total albumin (P = .025), prealbumin (P = .005), and albumin/ globulin (A/G) ratio (P = .008) were higher in females, and α- (P = .023) and β-globulins (P = .021) were higher in males of the same species. The following parameters differed significantly between the age groups: γ-globulins (P = .048) in greater and α- (P = .021) and β-globulins (P = .001) in American flamingos increased with increased age and percent total albumin (P = .002), total albumin (P = .024), and A/G ratio (P = .002) decreased with age in American flamingos. The results showed only small differences between the species, but greater differences between the sexes and ages, especially in American flamingos, which must be considered when interpreting laboratory results.

PLASMA BIOCHEMISTRY AND PROTEIN ELECTROPHORESIS REFERENCE INTERVALS OF THE COMMON LOON (GAVIA IMMER)

There are no published plasma biochemistry reference intervals for any species within the order Gaviiformes, which includes the common loon (Gavia immer). Because of their unique classification and lack of close taxonomic relatives, species-specific values for clinical data in loons are needed. This study determined reference intervals for plasma biochemical values in adult common loons, and reference intervals for protein electrophoresis values in both adult and juvenile common loons. Healthy, wild adult (n = 148, age >3 yr) and juvenile (n = 31, age 4-12 wk) common loons were sampled on freshwater summer breeding territories at study sites across North America. Plasma biochemical analytes included glucose (Glu), total calcium, phosphorus, sodium, potassium, chloride, blood urea nitrogen (BUN), uric acid, cholesterol, triglycerides, creatine kinase, γ-glutamyl transferase, alkaline phosphatase (ALP), lactate dehydrogenase, aspartate aminotransferase, amylase, and bile acids. Protein electrophoresis data included albumin to globulin ratio (A: G), prealbumin, albumin, α1-globulin, α2-globulin, β-globulin, and γ-globulin. Adult females had significantly higher Glu, ALP, and BUN than adult males. Juvenile loons had higher β-globulins than adults, whereas adults had higher α1-globulins. Establishment of complete reference intervals will improve clinical assessment of captive loons, and allow researchers to better understand the health of wild loons in response to the multiple environmental stressors faced by these species.

CLINICAL CHEMISTRY, VITAMIN, ELECTROPHORESIS, AND HEMATOLOGIC ANALYTES OF BLACK-HEADED IBIS (THRESKIORNIS MELANOCEPHALUS)

The evaluation of laboratory blood analytes is an important tool for health assessment in avian medicine. Unfortunately, there is a lack of suitable reference values for many zoo bird species. The goal of the present study was to establish reference intervals for a wide range of blood analytes in healthy black-headed ibis (Threskiornis melanocephalus) kept in a zoologic garden. Lithium heparinized blood samples from 15 individuals were collected, and 18 different clinical chemistry analytes were measured. New are especially the minimum and maximum values for bile acid (2.38-49.4 µmol/L), cholinesterase (439-1260 U/L), vitamin A (0.65-1.70 mg/L), vitamin E (26.3-52.5 mg/L), and capillary zone electrophoresis (prealbumin, 10.2-23.4%; albumin, 35.9-44.1%; A/G ratio, 1.07-1.69; α-, 15.7-20.0%; β-, 13.5-19.1%; γ-globulin, 6.08-11.3%). The measured values for clinical chemistry, vitamin, electrophoresis, and hematologic analytes are a basis for further studies and for diagnostics and clinical treatment in this ibis species.

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.

APPLICATION OF 3-HYDROXYBUTYRATE MEASUREMENT AND PLASMA PROTEIN ELECTROPHORESIS IN THE DIAGNOSIS OF ASPERGILLOSIS IN AFRICAN PENGUINS ( SPHENISCUS DEMERSUS)

New alternative laboratory means are needed to improve the options for antemortem diagnosis of avian aspergillosis. In this study, 3-hydroxybutyrate was measured in plasma samples collected from a cohort of African penguins ( Spheniscus demersus) maintained under human care. Results were interpreted in combination with those of protein electrophoresis and compared with anti- Aspergillus antibody and galactomannan antigen detection. Overall, 3-hydroxybutyrate levels were found significantly increased in Aspergillus-diseased cases versus the control penguin group ( P = 0.002). Mean absolute concentration of β-globulins was increased >20% in samples from infected birds, and α2-globublins were also found to be significantly increased versus clinically normal controls ( P < 0.001 and P = 0.001 respectively). Of note, the α2-globulins were also significantly increased versus penguins with inflammatory (non-aspergillosis) diseases ( P = 0.001). The specificity of 3-hydroxybutyrate, β-globulins, and α2-globulins for aspergillosis was 78.6%, 79.6%, and 92.2%, respectively. Using these measures in tandem resulted in high specificity (>90%) and negative predictive value (≥80%). In contrast, anti- Aspergillus antibody and galactomannan antigen did not distinguish between infected cases and controls ( P > 0.05). This study demonstrates that basic testing in tandem with the new biomarker 3-hydroxybutyrate may provide reliable evidence for the diagnosis of aspergillosis in penguins.

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 biochemistry RIs and age effect in European Strigiformes

BACKGROUND

Blood biochemistry and hematology are essential in the laboratory diagnosis of disease. In Strigiformes, little information regarding reference values and influence of different preanalytic factors is available, while age is known to have an effect on some biochemistry analytes, especially in early life characterized by a rapid growth rate and increase in body mass.

OBJECTIVE

The objective of this study was to determine baseline data for 29 blood biochemistry variables in 5 species of Iberian Strigiformes assigned to different age classes.

METHODS

Healthy nocturnal birds living in wildlife health centers of Catalonia, Northeastern Spain were assigned to different age classes (chicks, juveniles, adults where possible and available) and their blood was collected and analyzed for different standard biochemistry variables. Species included Tawny owls, Little owls, Long-eared owls, Scop owls, and Barn owls.

RESULTS

A total of 276 clinically healthy animals were sampled, including between 179 chicks, 52 juveniles, and 45 adults. The RIs of cholesterol, albumin, and osmolality were the only variables that did not show interspecific variability. Common trends between age class groups were observed in 4 species. Phosphorus and calcium concentrations and ALP activities decreased with increasing age, while concentrations of sodium and γ-globulins tended to increase in the Strigidae family. Differences were concentrated in chicks and no differences were observed between juveniles and adults in any variable.

CONCLUSIONS

Our results demonstrate the importance of defining biochemical RIs specific for certain age classes.

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.

Haematological and immunological characteristics of eastern hellbenders (Cryptobranchus alleganiensis alleganiensis) infected and co-infected with endo- and ectoparasites

Disease is among the leading causes of the global decline in amphibian populations. In North America, parasites and pathogens are among the factors implicated in precipitous population declines of the giant hellbender salamander (Cryptobranchus alleganiensis), but the incidence of infections and the responses of hellbenders to infections remain poorly studied. Here, we document the prevalence of leech and trypanosome infections in a wild population of eastern hellbenders (Cryptobranchus alleganiensis alleganiensis) and describe haematological and immunological characteristics of hellbenders harbouring these infections. We hypothesized that hellbenders parasitized by trypanosomes would be anaemic, that individuals infected with either or both parasites would exhibit shifts in white blood cell counts and that hellbenders infected with leeches would exhibit altered plasma bactericidal capacity. We found that 24 and 68% of hellbenders in our sample population were infected with leeches and trypanosomes, respectively, and 20% were co-infected with both parasites. We found no evidence suggestive of anaemia among infected individuals. However, hellbenders infected with either or both parasites exhibited marked shifts in circulating white blood cells that were consistent with predictable responses to parasitic infection. Additionally, we found that hellbenders harbouring leeches had much higher plasma bactericidal capacity than individuals without leeches, and we offer multiple potential mechanistic explanations for this observation. We also found evidence that cellular and serological immune responses to parasites were less robust in juvenile than adult hellbenders. This finding warrants further investigation in light of the demographic characteristics, specifically the scarcity of juvenile age classes, of hellbender populations where disease is a possible contributor to declines. Finally, we describe two methodological advances that will improve future studies seeking to diagnose trypanosome infections and to test the bactericidal capacity of hellbenders and perhaps other amphibians. Our study provides fundamental insights into how hellbenders respond physiologically to endo- and ectoparasites, which could ultimately prove useful for their conservation.

Establishment of reference intervals for plasma protein electrophoresis in Indo-Pacific green sea turtles, Chelonia mydas

Biochemical and haematological parameters are increasingly used to diagnose disease in green sea turtles. Specific clinical pathology tools, such as plasma protein electrophoresis analysis, are now being used more frequently to improve our ability to diagnose disease in the live animal. Plasma protein reference intervals were calculated from 55 clinically healthy green sea turtles using pulsed field electrophoresis to determine pre-albumin, albumin, α-, β- and γ-globulin concentrations. The estimated reference intervals were then compared with data profiles from clinically unhealthy turtles admitted to a local wildlife hospital to assess the validity of the derived intervals and identify the clinically useful plasma protein fractions. Eighty-six per cent {19 of 22 [95% confidence interval (CI) 65-97]} of clinically unhealthy turtles had values outside the derived reference intervals, including the following: total protein [six of 22 turtles or 27% (95% CI 11-50%)], pre-albumin [two of five, 40% (95% CI 5-85%)], albumin [13 of 22, 59% (95% CI 36-79%)], total albumin [13 of 22, 59% (95% CI 36-79%)], α- [10 of 22, 45% (95% CI 24-68%)], β- [two of 10, 20% (95% CI 3-56%)], γ- [one of 10, 10% (95% CI 0.3-45%)] and β-γ-globulin [one of 12, 8% (95% CI 0.2-38%)] and total globulin [five of 22, 23% (8-45%)]. Plasma protein electrophoresis shows promise as an accurate adjunct tool to identify a disease state in marine turtles. This study presents the first reference interval for plasma protein electrophoresis in the Indo-Pacific green sea turtle.

Reference intervals, longitudinal analyses, and index of individuality of commonly measured laboratory variables in captive bald eagles (Haliaeetus leucocephalus)

The objectives of this study were to determine reference intervals, perform longitudinal analyses, and determine the index of individuality (IoI) of 8 hematologic, and 13 biochemical and electrophoretic variables for a group of captive bald eagles (Haliaeetus leucocephalus). Reference intervals were determined from blood samples collected during annual wellness examinations for 41 eagles (23 male and 18 female) with ages ranging between 6 and 43 years (18.7 +/- 7.4, mean +/- SD) at the time of sample collection. Longitudinal analyses and IoI were determined for measured hematologic, biochemical, and protein electrophoretic variables, both individually and as a group, for a subset of 16 eagles (10 male and 6 female) during a 12-year period. This smaller group of eagles ranged in age between 2 and 20 years at the start of the study period, and between 14 and 32 years (21.9 +/- 5.0, mean +/- SD) at the end of the study period. Significant increases with age within the group of 16 eagles were observed only for red blood cells, percent heterophils, total protein, and beta-globulin protein fraction, while albumin:globulin decreased significantly with age. A low IoI (> or = 1.4) was determined for all hematologic and biochemical variables except gamma globulins, which had high IoI (< or = 0.6) for 3 individuals within the subset of 16.

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.

Applications of serum protein electrophoresis in exotic pet medicine

Serum Protein Electrophoresis (SPE) is a useful diagnostic and prognostic tool in human and companion animals medicine: several experiences show that it can be useful in exotic practice as well. The fundamentals of SPE interpretation as well as some normal and pathological patterns for the species most commonly seen in practice are provided.

Diagnosis of mycobacterial infections in the exotic pet patient with emphasis on birds

The term “mycobacteriosis” encompasses a variety of infectious diseases of animals caused by bacteria of the genus Mycobacterium, which are chronic and debilitating diseases. More than 35 Mycobacterium spp can cause mycobacteriosis. The wide range of possible clinical signs and physical exam findings can make the antemortem diagnosis inconsistent and challenging. Proper sample collection and test modality in relation to the state of the disease process are essential. Clinicians can determine a presumptive diagnosis of mycobacteriosis, but the definitive etiologic diagnosis of mycobacteriosis relies on the correct identification of the mycobacteria through microbiological and molecular diagnostic methods.

Invalid measurement of plasma albumin using bromcresol green methodology in penguins (Spheniscus species)

The purpose of this study was to examine the validity of albumin determinations in penguin plasma by the bromcresol green (BCG) method and the gold standard of protein electrophoresis (EPH). Plasma from 96 clinically normal and abnormal penguins (Spheniscus species) was analyzed. The 2 methods did not yield equivalent results. The BCG method underestimated the albumin level in samples from normal patients (indicated by a normal albumin:globulin ratio) and overestimated the albumin level in samples from clinically abnormal penguins (indicated by a decreased albumin:globulin ratio). After EPH of plasma samples from clinically abnormal penguins samples was performed to separate albumin and globulin fractions, the globulins exhibited marked binding to the BCG dye. There were no significant differences between the variable reaction of paired serum and plasma samples when using the BCG method. These results demonstrated marked differences in the determination of albumin levels when using the BCG method and protein EPH. They further demonstrated that the BCG method can provide erroneous results, which have the potential to significantly impact clinical diagnosis and treatment. This study confirmed findings from previous studies in other avian species that the BCG method yields unreliable results in avian species. It is our conclusion that the BCG method, commonly found on automated analyzers in commercial laboratories and on point-of-care analyzers, should not be used to determine albumin concentration in avian samples.

Natural cross chlamydial infection between livestock and free-living bird species

The study of cross-species pathogen transmission is essential to understanding the epizootiology and epidemiology of infectious diseases. Avian chlamydiosis is a zoonotic disease whose effects have been mainly investigated in humans, poultry and pet birds. It has been suggested that wild bird species play an important role as reservoirs for this disease. During a comparative health status survey in common (Falco tinnunculus) and lesser (Falco naumanni) kestrel populations in Spain, acute gammapathies were detected. We investigated whether gammapathies were associated with Chlamydiaceae infections. We recorded the prevalence of different Chlamydiaceae species in nestlings of both kestrel species in three different study areas. Chlamydophila psittaci serovar I (or Chlamydophila abortus), an ovine pathogen causing late-term abortions, was isolated from all the nestlings of both kestrel species in one of the three studied areas, a location with extensive ovine livestock enzootic of this atypical bacteria and where gammapathies were recorded. Serovar and genetic cluster analysis of the kestrel isolates from this area showed serovars A and C and the genetic cluster 1 and were different than those isolated from the other two areas. The serovar I in this area was also isolated from sheep abortions, sheep faeces, sheep stable dust, nest dust of both kestrel species, carrion beetles (Silphidae) and Orthoptera. This fact was not observed in other areas. In addition, we found kestrels to be infected by Chlamydia suis and Chlamydia muridarum, the first time these have been detected in birds. Our study evidences a pathogen transmission from ruminants to birds, highlighting the importance of this potential and unexplored mechanism of infection in an ecological context. On the other hand, it is reported a pathogen transmission from livestock to wildlife, revealing new and scarcely investigated anthropogenic threats for wild and endangered species.

AN INTRODUCED GENERALIST PARASITE, THE STICKTIGHT FLEA (ECHIDNOPHAGA GALLINACEA), AND ITS PATHOLOGY IN THE THREATENED FLORIDA SCRUB-JAY (APHELOCOMA COERULESCENS)

The sticktight flea, (Echidnophaga gallinacea), a major pest of the domestic chicken (Gallus gallus) that can cause severe pathology or death if untreated, is rarely recorded in free-living avian species. Sticktight fleas, however, were observed on the federally threatened Florida scrub-jay (Aphelocoma coerulescens) in February 2004, in south central Florida. Of the 81 Florida scrub-jays (FSJs) sampled before the 2004 breeding season, 12 were infested, with from 1 to as many as 57 fleas. Subsequent survivorship and variation in health indices led us to conclude that the sticktight flea caused the death of several jays. Within 4 mo, 46% of sticktight flea-infested (INF) jays died, whereas in the nonflea-infested (NINF) jays, only 5.9% died. Adult INF birds lost body mass in the time since a previous capture compared with NINF jays, and mass gain was slowed in 1-yr-old INF jays. Hematocrit of INF jays was dramatically impacted, as low as 17%, and was negatively correlated with the extent of infestation. Leukocyte counts were highest in INF jays; however, plasma immunoglobulin levels were lowest. Physiological stress levels, measured using plasma corticosterone, increased more rapidly in INF jays than NINF jays and were positively correlated with heterophil/lymphocyte ratios. The impact of the sticktight flea on the federally threatened FSJ negates previous findings that sticktight fleas are benign in wild avian hosts.

Antioxidant protection and plasma carotenoids of incubating great tits (Parus major L.) in relation to health state and breeding conditions

Carotenoids are biologically active pigments, which are important for animals due to their dual role in health maintenance and ornamental signalling. In adult birds, immunostimulatory properties of carotenoids have been repeatedly demonstrated while much less is known about the importance of carotenoids as antioxidants. We studied the relationships between plasma carotenoid levels, as well as total antioxidant protection, and various hemato-serological health state indices in female great tits (Parus major L.), incubating their second clutches in two contrasting (coniferous and deciduous) habitats in southwest Estonia. To manipulate reproductive effort, four eggs were removed from half of the clutches during laying to stimulate females to lay additional eggs. However, egg removal had no effect on the final number of eggs laid. Plasma carotenoid levels increased seasonally in parallel with caterpillar food availability. However, no between-habitat differences in carotenoid levels, total antioxidant capacity, or indices of health state could be found despite the apparently better feeding conditions in the coniferous habitat. No correlation was detected between plasma carotenoid levels and measures of total antioxidant capacity, which suggests that at least for the adult birds feeding on naturally carotenoid-rich diet, antioxidant function of carotenoids is not of primary importance. A strong non-linear association between the measures of antioxidant protection and leukocytic markers of inflammation was found, which suggests that measures of total antioxidant capacity deserve further attention in ecophysiological studies as potential indicators of immunopathology.

Diagnosis and successful treatment of a presumptive case of aspergillosis in a Micronesian kingfisher (Halcyon cinnamomina cinnamomina)

A 4-yr-old male Micronesian kingfisher was suspected of having an aspergillus infection. The infection was thought to be related to stress associated with movement to a new enclosure/exhibit and cage-mate aggression. The diagnosis was based on an elevated white cell count, positive antibody and antigen aspergillus titers, and abnormal plasma protein electrophoresis characterized by a moderate elevation of alpha2 and severe elevation on the beta protein fractions. The bird was treated with antifungal medication administered systemically and by nebulization for 10 wk. Response to treatment was monitored by serial white cell counts and plasma electrophoresis. Clinical improvement in this bird was correlated with a return of the white blood cell count to normal levels and what was considered a normal protein electrophoresis distribution.

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.

Fungal diseases of birds of prey

Aspergillosis and candidiasis are ranked among the most common infectious diseases in birds of prey. The prevention of these fungal diseases is often easier than treatment. Thus the clinician should strive to prevent infection by minimizing stress, maintaining a healthy environment, limiting long-term use of antibiotics and corticosteroids, and reducing exposure to fungal organisms. Although less commonly diagnosed among wild, free-ranging birds of prey, a high incidence in a free-ranging population should make the clinician think of an immunocompromising factor (i.e., toxins, human encroachment or low prey base) that may be contributing to infection. The diagnosis of aspergillosis and candidiasis often requires more than just the identification of the agent, as these ubiquitous organisms often are cultured from healthy birds of prey. In those birds of prey in which a fungal infection is highly suspected or proven, antifungal drugs remain the mainstay of treatment, although available drugs and modes of delivery have improved in recent years.