Different Species Of Birds Research Articles

Analysis of Newcastle disease virus prevalence in wild birds reveals interhost transmission of genotype VI strains.

Surveillance of Newcastle disease viruses (NDVs) has been conducted primarily in poultry, but their prevalence in wild birds remains largely unknown. Increasing our understanding of the ecology and evolution of NDVs in different species of birds will help us develop better prevention and control strategies. In this study, large-scale epidemiological sampling of resident wild birds in Guangxi from 2016 to 2019 was performed. The results demonstrated that different genotypes, especially genotype VI NDVs, circulated among resident wild birds. Our findings highlight the potential threat to the pigeon industry and public health.

Recording potential predators of herpetofauna in southern Mexico using camera traps and realistic models

ABSTRACT Knowledge of biotic predator–prey interactions is essential for understanding the role of species in the food web; however, information on these interactions is scarce for most species. Our aim in this study was to gather information on the potential predators of two species of herpetofauna abundant in the rainforest they inhabit, the frog Craugastor loki and the snake Ninia sebae. For this, realistic models of the two species were placed, and monitored using camera traps, in 13 sites located in a forest fragment belonging to a private protected natural area in southern Veracruz in three seasons (dry, rainy and windy) in 2019. In addition, the temporality and seasonality of the events and some behaviours of the potential predators are described. The recorded events were classified into four categories: presence, interest, contact and aggression. For C. loki, 159 events of appearances of potential predators were identified (32 with interaction: 18 events of interest, 2 contact and 12 aggressions). The aggressions were carried out by the mammals Didelphis marsupialis and Peromyscus sp. In the case of N. sebae, 201 appearances of potential predators were identified (75 with interaction: 36 events of interest, 7 contact and 32 aggressions). The aggressions were carried out by 10 species (seven birds and three mammals). Bird predation events towards models of both species occurred during daytime while the attacks by mammals occurred at night. Agonistic behaviours included pecking, biting and urine marking, previously unknown. Events of each category were recorded every season. Our results indicate that C. loki and N. sebae may have more predators than were previously known, and suggest that these species can be an important food resource for different species of birds and mammals in the environments where they live.

Heterogeneric Diversity and Richness of Avifauna in a Degraded Landscape of Arial Beel in Bangladesh

Bird diversity and richness reflect the habitat quality of ecosystems. The species composition, diversity, and richness of birds were studied at Shologhar Union, a degraded landscape of Arial Beel, from March 2016 to February 2017, using line transect and point count methods. A total of 75 species of birds belonging to 14 orders and 35 families were recorded; most of them were residents (83%). Non-passerine birds were predominant (40 species, 53% of total species), with 18 families and 38 genera. Only one near-threatened species (Yellow Wattled Lapwing Vanellus malabaricus) was recorded. Among resident birds, Baya weaver (Ploceus philippinus) was dominant, and the Yellow Wagtail (Motacilla flava) was predominant among migratory birds. Most species were terrestrial (51 spp., 68% of total birds), contributing only 23% of the population. The individual rarefaction revealed the highest species richness in March and the lowest in May and June. The highest population was recorded in winter (38%), and insectivore species (40%) were the highest. No significant seasonal variation occurred in the richness of birds (Kruskal-Wallis test: K = 0.05 df = 2, p = 0.971) and in different feeding guilds (Kruskal-Wallis test: K = 0.86, df = 5, p = 0.65). Ardeidae and Sturnidae represented the highest diversified families (6 species in each, RDi = 8), and Baya Weaver contributed the highest (26%) population. The presence of different species of birds suggests that this site could provide a suitable habitat for wild birds, and restoration management of this part of Arial Beel should require conserving the habitat of avifauna. Jagannath University Journal of Life and Earth Sciences, 9(1): 19-44, 2023 (June)

Feature alignment via mutual mapping for few-shot fine-grained visual classification

Few-shot fine-grained visual classification aims to identify fine-grained concepts with very few samples, which is widely used in many fields, such as the classification of different species of birds in biological research, and the identification of car models in traffic monitoring. Compared with the common few-shot classification task, it encounters difficulties due to significant variations within each class and small gaps between different categories. To address such problems, previous studies primarily project support samples into the space of query samples and employ metric learning to classify query images into their respective categories. However, we observe that such methods are not effective in resolving inter-class variations. To overcome this limitation, we propose a new feature alignment method based on mutual mapping, which simultaneously considers the discriminative features of new samples and classes. Specifically, besides projecting support samples into the space of query samples for reducing intra-class variations, we also project query samples into the space of support samples to increase inter-class variations. Furthermore, a direct position self-reconstruction module is proposed to utilize the location information of objects and obtain more discriminative features. Extensive experiments on four fine-grained benchmarks demonstrate that our approach is competitive when compared with other state-of-the-art methods, in both 1-shot and 5-shot settings. In the case of 5-shot, our method achieved the best performance on all four datasets, with 92.11%, 85.31%, 96.09%, and 94.64% accuracies on CUB-200-2011, Stanford Dogs, Stanford Cars, and Aircaft, respectively.

The Effect of Maternal Hormones on the Avian Offspring: A Review

Maternal hormones have a significant impact on the development of avian embryos, controlling vital physiological functions such as immune system development, metabolism control, and productive traits. This review will examine the different types of maternal hormones, synthesis, regulation, and effects on avian physiology and productivity, as well as the implications for embryonic development. Additionally, it appears that how they might affect hatchability and chick quality. Studies have shown that maternal hormones transfer to eggs and subsequently affect the offspring's development, greatly influencing the behavior and phenotype of avian offspring overall. Understanding these mechanisms can help improve our knowledge of developmental biology, parental investment, and evolutionary processes that influence avian traits. Different species of birds may experience different effects when exposed to maternal hormones. For example injecting testosterone into bird eggs can increase the rate at which certain species hatch, such as quail, other species may see a decrease in hatchling weight. This emphasizes the complexity of hormonal influences on bird development and the necessity of more research. In particular, it is still unclear how yolk steroids affect birds' immune systems; early research indicates that they may chickens' ability to produce antibodies. Undertaking further research is necessary to completely understand the implications of avian immunity to fill in these gaps in knowledge across species and developmental stages.

Mapping Dissolved Organic Carbon and Organic Iron by Comparing Deep Learning and Linear Regression Techniques Using Sentinel-2 and WorldView-2 Imagery (Byers Peninsula, Maritime Antarctica)

Byers Peninsula is considered one of the largest ice-free areas in maritime Antarctica. Since 2006, the Spanish Polar Program has taken part in a large number of environmental studies involving the effects of climate change on biological life cycles, limnology, and microbiology. Soils from maritime Antarctica are generally weakly developed and have chemical, physical, and morphological characteristics that are strongly influenced by the parent material. However, biological activity during the short Antarctic summer promotes intense transference of nutrients and organic matter in areas occupied by different species of birds and marine mammals. Mapping and monitoring those areas that are highly occupied by various species could be very useful to create models prepared from satellite images of the edaphic properties. In this approach, deep learning and linear regression models of the soil properties and spectral indexes, which were considered as explicative variables, were used. We trained the models on soil properties closely related to biological activity such as dissolved organic carbon (DOC) and the iron fraction associated with the organic matter (Fe). We tested the best approach to model the spatial distribution of DOC, Fe, and pH by training the linear regression and deep learning models on Sentinel-2 and WorldView-2 images. The most robust models, the pH model built with the deep learning approach on Sentinel images (MAE of 0.51, RMSE of 0.70, and R2 with a residual of −0.49), the DOC model built with linear regression on Sentinel images (MAE of 189.39, RMSE of 342.23, and R2 with a residual of 0.0), and the organic Fe model built with deep learning (MAE of 116.20, RMSE of 209.93, and R2 of −0.05), were used to track possible areas with ornithogenic soils, as well as areas of Byers Peninsula that could be supporting the highest biological development.

Composition of encephalic arteries and origin of the basilar artery are different between vertebrates.

Intracranial arterial anatomy is lacking for most mammalian and non-mammalian model species, especially concerning the origin of the basilar artery (BA). Enhancing the knowledge of this anatomy can improve animal models and help understanding anatomical variations in humans. We have studied encephalic arteries in three different species of birds and eight different species of mammals using formalin-fixed brains injected with arterial red latex. Our results and literature analysis indicate that, for all vertebrates, the internal carotid artery (ICA) supplies the brain and divides into two branches: a cranial and a caudal branch. The difference between vertebrates lies in the caudal branch of the ICA. For non-mammalian, the caudal branch is the origin of the BA, and the vertebral artery (VA) is not involved in brain supply. For mammals, the VA supplies encephalic arteries in two different ways. In the first type of organization, mostly found in ungulates, the carotid rete mirabile supplies the encephalic arteries, the caudal branch is the origin of the BA, and the VA is indirectly involved in carotid rete mirabile blood supply. The second type of encephalic artery organization for mammals is the same as in humans. The caudal branch of the ICA serves as the posterior communicating artery, and the BA originates from both VAs. We believe that knowledge of comparative anatomy of encephalic arteries contributes to a better understanding of animal models applicable to surgical or radiological techniques. It improves the understanding of rare encephalic variations that may be present in humans.

A New Efficient Classifier for Bird Classification Based on Transfer Learning

The problem of classification of different species of birds in the images is relevant in the modern world. The essence is to automatically determine the species of birds depicted in the photo using artificial intelligence. It is important for several areas of human life, in particular for nature conservation, environmental research, education, and ecotourism. The development of a classifier, based on deep learning methods, can help to effectively solve the problem of classifying different species of birds, ensuring high accuracy. The work developed a new effective algorithm for the classification of different species of birds in the images. An optimal model architecture was built using the transfer learning approach. A dataset of 525 bird species was analyzed and preprocessed in detail. The model training process was carried out, which includes two phases: only the upper layers are deactivated and the last 92 layers of the pretrained EfficientNetB5 model (not including BatchNormalization layers) and the top layers are activated. As a result, efficacy indicators were obtained: accuracy = 98.86%, precision = 0.99, recall = 0.99, and F1 score = 0.99, which showed improvement in comparison with modern research. The developed classifier is best suited for such areas of human life as education and ecotourism because for them the number of different species of birds that the classifier can determine is very important.

Neurological examination of clinically healthy pigeons (Columba livia domestica), mute swans (Cygnus olor), common buzzards (Buteo buteo), common kestrels (Falco tinnunculus) and northern goshawks (Accipiter gentilis).

A neurological examination is essential for determining the localisation of neurological lesions. However, in avian species, quantitative data regarding the practicability and feasibility of neurological tests are very limited. Therefore, the aim of this study was to establish normative data for the neurological examination of clinically healthy birds of different species. Forty-two domestic and feral pigeons (Columba livia domestica), 42 mute swans (Cygnus olor), 12 common buzzards (Buteo buteo), 24 common kestrels (Falco tinnunculus) and six northern goshawks (Accipiter gentilis) were examined. All birds underwent a predefined neurological examination. Interobserver variations between three examiners were investigated in 11 pigeons and 11 mute swans. All postural reaction tests, except for the drop and flap reaction in mute swans, provoked a consistent response in pigeons and mute swans, whereas postural reaction tests of the legs in raptors were often not performable. Cranial nerve tests and most of the spinal reflexes revealed variable responses in all birds. The gastrocnemius reflex was not provokable in any bird. Interobserver agreement was almost perfect (Gwet's AC1 coefficient ≥0.81) for 16 of 21 parameters in the examination in pigeons and for 14 of 21 in mute swans. The inclusion of free-ranging birds, which were not used to handling and for which limited information regarding age, history of previous diseases, etc. was available, may have influenced the results. The normative neurological examination data provided in this study will help improve clinicians' interpretation of neurological examinationresults in the respective bird species.

Fine-Scale Map Reveals Highly Variable Recombination Rates Associated with Genomic Features in the Eurasian Blackcap.

Recombination is responsible for breaking up haplotypes, influencing genetic variability, and the efficacy of selection. Bird genomes lack the protein PR domain-containing protein 9, a key determinant of recombination dynamics in most metazoans. Historical recombination maps in birds show an apparent stasis in positioning recombination events. This highly conserved recombination pattern over long timescales may constrain the evolution of recombination in birds. At the same time, extensive variation in recombination rate is observed across the genome and between different species of birds. Here, we characterize the fine-scale historical recombination map of an iconic migratory songbird, the Eurasian blackcap (Sylvia atricapilla), using a linkage disequilibrium-based approach that accounts for population demography. Our results reveal variable recombination rates among and within chromosomes, which associate positively with nucleotide diversity and GC content and negatively with chromosome size. Recombination rates increased significantly at regulatory regions but not necessarily at gene bodies. CpG islands are associated strongly with recombination rates, though their specific position and local DNA methylation patterns likely influence this relationship. The association with retrotransposons varied according to specific family and location. Our results also provide evidence of heterogeneous intrachromosomal conservation of recombination maps between the blackcap and its closest sister taxon, the garden warbler. These findings highlight the considerable variability of recombination rates at different scales and the role of specific genomic features in shaping this variation. This study opens the possibility of further investigating the impact of recombination on specific population-genomic features.

Defining priority areas for conservation based on multispecies functional connectivity

Habitat fragmentation poses a significant challenge to biodiversity conservation. Well-designed ecological corridors can effectively enhance connectivity between habitat areas, particularly within Protected Areas (PAs), thereby mitigating biodiversity loss. Herein, we proposed a methodological approach for identifying Priority Areas for Conservation (PACs) of biodiversity based on functional connectivity for different species of birds and terrestrial mammals. We applied the proposed methodology in a biodiverse region in Brazil that harbors a mosaic of PAs and remaining areas of natural vegetation under anthropogenic pressure, primarily from mineral extraction activities. We used ecological corridor simulations as input data and a set of geographic information systems tools to delineate the priority areas. In total, we identified 24 priority areas for the conservation of 10 bird and 5 mammal species under different extinction threat levels and preferential habitat types, which varied among seasonal semideciduous forests, savannas, and rupestrian grasslands. The sizes of the priority areas identified ranged from 834.42 to 7954.36 ha. The proposed methodology can be applied to define priority areas for biodiversity conservation at a regional scale for different species or groups of species worldwide.

Characterization and seminal cryopreservation of three species of birds of prey.

Assisted reproduction techniques in birds have contributed to many species' conservation and sustainable use. One of these techniques is semen cryopreservation, which is possible following the discovery of suitable cryoprotectants. This study aimed to characterize the fresh and post-thaw ejaculates of different species of birds of prey. The following species were included in the study: red-tailed hawk (Buteo jamaicensis) n=3, golden eagle (Aquila chrysaetos) n=3, and Harris's hawk (Parabuteo unicinctus) n=3. Twenty-five ejaculates were obtained for each species. The percentage of spermatozoa motility, viability, and morphology were evaluated. Evident differences were observed among the ejaculates of the three species, particularly in sperm length and between the fresh and post-thaw parameters of the same species in which the motility reduced to approximately 40% after thawing. It was demonstrated that sperm cryopreservation of the studied species was possible using the same freezing protocol. This study showed that sperm characteristics could influence the parameters obtained during their in vitro conservation, both in the fresh and post-thaw states.

Comparative Macro- and Micro-morphological Study on the Syrinx of Three Avian Species

This study aimed to explain and compare the anatomical, histological, histochemical & histomorphometric analyses of the syrinx in different species of birds. This study includes 21 healthy birds from geese (Anser Anser Domesticus), cattle egrets (Bublucus ibis) & house sparrows (Passer domesticus), seven from each species. Results: Anatomically, the syrinx of the three studied species was tracheobronchial type composed of 2 different cartilaginous groups arranged in three parts: Tracheo-Syringeal cartilage in (cranial, intermediate part (tympanum)) and broncho-syringeal cartilage; as well as the trachea's muscles were once thought to be the syrinx's extrinsic muscles. Histologically, the lamina epithelialis of the Tracheo-Syringeal part was represented by pseudostratified ciliated columnar epithelium in the three investigated species with goblet cells in geese, house sparrows and lack goblet cells in cattle egrets. The pessulus in all three investigated species was triangular and positioned at the tip of the tracheal bifurcation. The bulla of house sparrow was considered the intrinsic syringeal muscles and these muscles in sparrows are not only present in geese or cattle egrets.

Performacnes comparison of CNN-based models for fine-grained image classification

Fine-grained visual classification is regarded as a more refined classification that can identify specific types of objects. It has been widely used in commodity sales, vehicle recognition and person recognition, etc., and has played a great value in many fields. For example, it requires an algorithm to identify different species of birds or dogs to facilitate more practical applications. This task is difficult since the objects has similar appearance and there exist obvious intra-class variance and limited inter-class differences, where different kinds of birds could share very similar appearance. Deep learning techniques has been applied to image recognition, natural language processing, and many other fields. Several approaches tackling the fine-grained classification problem are proposed. To further demonstrate the different designs of these solutions, in this paper, fine-grained identification methods are compared and analyzed, among which WS-DAN achieves better results and it is preferred to be an effective method, which is expected to be more widely used in this field.

Применение желточных антител птиц в медико-биологических исследованиях

Passive immunization, proposed by E. Behring, is still a sought-after treatment option using mammalian antibodies. This principle was developed by F. Klemperer in 1893, showing that antibodies that could inactivate the pathogen appeared in the egg yolks of chickens immunized with tetanus toxin. At this time, E. Behring, S. Kitasato, and other investigators studied the inactivating properties of mammalian sera, and an article by F. Klemperer on the transfer of active antibodies from chicken blood to egg yolk remained unattended. Only after the publication of the 3Rs principles by W.M.S. Russell and R.L. Burch in 1959, it was realized that the extraction of egg yolks from immunized birds was fully consistent with the principles of bioethics because the procedure was physiological and non-invasive. Researchers in many countries began to study the yolk immunoglobulins of birds of different species and use them in the diagnosis, therapy and prevention of human and animal diseases. The following species of birds are used for production of IgY-antibodies: chicken, quail, duck, goose, ostrich. Extraction of immunoglobulins from egg yolks of birds is not a difficult task. Many options for the isolation and purification of yolk immunoglobulins from different avian species have been described in the literature. IgY technology has attracted a lot of interest among researchers, especially in the last 10 years. In addition, advances in laboratory techniques and the application of other technologies in the field have resulted in IgY technology becoming more mature for industrial production of specific antibodies and commercialization of the process. Companies are emerging in many countries producing transovarian (yolk) antibodies against pathogens that cause dental caries, peptic ulcer, celiac disease and other diseases. IgY-technologies are a relatively new direction in immunology, based on the passive immunization technology of E. Behring, but it is not sufficiently appreciated in Russia. The replacement of mammalian IgG with avian transovarial IgY allows to develop commercially significant amounts of specific antibodies that do not cause side effects, expands the possibilities of passive immunization methods for the treatment of lesions caused by viruses, bacteria and toxins. This review describes the properties of IgY from different avian species and examples of their application in therapy and disease prevention.

A retrospective study on the treatment of bone fractures in 14 wild birds of different species and ages by bone muffs

Various kinds of fracture fixation methods have been applied in bird orthopedics. Although each one has comparative advantages and disadvantages, the best results can be obtained with the orthopedic technique chosen according to the location, shape and type of the fracture. In addition, postoperative care of animals, especially rehabilitation of wild birds, will yield positive results. The aim of this retrospective study was to evaluate the advantage of bone muffs in comparison to other routine fracture treatment methods, such as a bandages, intramedullary pins, and cerclage applications. Several wild birds with leg and wing fractures were admitted to the Clinical and Animal Hospital of the F.Ü. Veterinary Faculty between 1986 and 2011, and were treated with bandages, cerclage, and intramedullary pin techniques. Of these, 14 birds were treated with bone muffs. The animals were anesthetized for osteosynthesis with Pentobarbital (Nembutal sodium 50 mg/cc, ABBOTT) or ketamine (ketalar 50 mg/ml PARKE-DAVİS). Appropriately sized cattle and bird bone muffs were firmly fixated onto fractured bone fragments and their recovery was monitored. After the operation, the animals were taken for post-operative care. Animals with muff transplants did not need to be treated with bandages, and hence they were calmer, more comfortable and healed quickly. In birds treated with a bone muff, the bone to which the muff was applied was observed by histopathology to have normal callus formation and it was reported that a bone callus formed at that region. On the other hand, animals treated with other routine fracture management methods and bandaged animals were uncomfortable, aggressive, and were observed to be under stress. These bandaged birds had a longer recovery time, and during this time, most of the animals refused to eat and died. Due to the bandage, the animals could not find their balance on a single wing, they became disturbed psychologically, and did not continue to feed, so began to vomit when fed by hand and died in a short time. From this point of view, bone muffs provided significant advantages over other routine applications, as they did not cause psychological stress to animals because they were light and the birds did not require bandages, and they were easily resorbed because they were made of bone tissue. Recovery time was also shorter. The study showed that bone muffs may be better than conservative treatment, however, further research is needed as real long-term results are lacking.

Cell culture adaptation of Avipox viruses isolated from different species of birds

Avianpox (AP) is an infectious, slow spreading viral disease that has been reported to affect numerous species of birds including poultry. There is very limited information available regarding the molecular and biological characteristics of the avipox viruses (APVs) circulating in India. In the present study, APVs from fowl [FP/As- K(R)], pigeon [P2/ As- K9(R)] and duck [D2/ As- N] origin isolated from natural outbreaks of the disease in different areas of Assam were selected for adaptation in different cell culture. All the three isolates were propagated in chicken embryo fibroblast (CEF) primary cell culture and Vero cell line and their propagation was confirmed by observing virus specific cytopathic effects (CPE) and by performing PCR targeting the 4b gene of APV. All three isolates were adapted in the CEF primary culture with production of virus specific CPE. However, a high degree of CPE was observed in the cultures infected with the fowl isolate from an earlier passage (P-11) in comparison to the other two isolates. Even the time required for completion of CPE was considerably less in case of the fowl isolate. The log TCID50 of the fowl isolate was found to be 4.18 ± 0.11, 5.29 ± 0.06 and 6.29 ± 0.13, respectively in the 5th, 15th and 20th passage, which was higher in comparison to the other two isolates. Interestingly, none of the isolates showed any virus specific CPE in vero cell line on propagation till the 10th passage. Moreover, all the passages were found to be negative by PCR.

Methods of analgesia and euthanasia in backyard poultry

The keeping of chickens in the backyard is growing in popularity in urban and suburban areas, numbers of animals are increasing and as a result small animal practitioners are more and more frequently faced with chickens as patient. Clinical conditions in backyard poultry often require the treatment of pain. The challenges regarding the adequate use of analgesics include: 1. Recognition and assessment of pain, which necessitates good knowledge of chicken behaviour, 2. Selection of the adequate drug and dosage based on evidence that is often not available for chickens, but spread over different species of birds, and 3. Implementation of food safety regulations, which result from the dual use of backyard poultry as «food producing pets». Analgesics used in chickens include opiates, nonsteroidal anti-inflammatory drugs and local analgesics. The opiate butorphanol has been shown to have an analgesic effect of approximately two hours in chickens. Tramadol and methadone show some promise as analgesics, but more evidence is needed especially regarding bioavailability. The nonsteroidal anti-inflammatory drugs meloxicam and carprofen appear to have an analgesic effect. Variable metabolism between breeds of chickens and the risk of accumulation, especially when used for periods exceeding five consecutive days, need to be taken into account regarding dosage. Lidocaine and bupivacaine have successfully been used in chickens for nerve blocks and spinal anaesthesia and should be included as part of multimodal analgesia especially during surgery. In cases, where termination of life is necessary the preferred method consists of an injectable anaesthesia followed by intravenous application of a barbiturate.

Pathological features of West Nile and Usutu virus natural infections in wild and domestic animals and in humans: A comparative review

Mosquito-borne flaviviruses are emerging pathogens with zoonotic potential. Due to the recent climate and environmental changes, they are spreading across Europe, becoming a major threat for public and veterinary health. West Nile virus (WNV) and Usutu virus (USUV) are arboviruses that are responsible for multiple disease outbreaks in different species of birds, reptiles, and mammals, including humans. This review reports and compares the clinical signs as well as the gross and microscopic pathological features during natural infection with WNV and USUV in wild and domestic animals, as well as in humans. The main objective of this comparative review is to delineate the common features and the specific differences that characterize WNV- and USUV-induced diseases in each group of species and to highlight the main gaps in knowledge that could provide insight for further investigation on the pathogenesis and neurovirulence of these viruses.

Comparison of blood biochemical parameters of four species of vultures.

Vultures play a very important role in ecosystems by feeding on dead animals and preventing the spread of pathogens. In the mid-20th century in Bulgaria, all species of vultures experienced a rapid population decline and conservation measures include captive breeding and release via adaptation aviaries. Knowledge of the baseline blood biochemical parameters is crucial for the care, rehabilitation and prior to the release of endangered birds of prey. Plasma levels provide valuable information for the evaluation of the physical condition of animals. Between 2020 and 2022, we took blood samples from captive Bearded, Griffon, Cinereous and Egyptian Vultures in Bulgaria (n = 118). We determined the values of 18 parameters - alanine transaminase, albumin, alkaline phosphatase, amylase, aspartate transaminase, calcium, chloride, cholesterol, creatine kinase, creatinine, glucose, lactate dehydrogenase, magnesium, phosphorus, total bilirubin, total protein, triglycerides and uric acid. This research determined the mean blood biochemical indices for aviary Bearded, Griffon, Cinereous and Egyptian Vultures in Bulgaria and compared the values amongst the four vulture species, to serve in determining clinical pathology and nutrition for scavenger birds of different species, age groups and genders in the country. The results of this study suggested that there are significant differences between many of the indicators of the four vulture species. There are fewer differences in the indicators of different ages of birds of a given species and almost no differences are found between the two sexes of a species. These values could be used by scientists, veterinary pathologists, wildlife rehabilitation centres and other researchers. Furthermore, the use of such parameters in assessing population health may enable conservationists to further research environmental conditions affecting the vultures' reproduction and survival.