Comparison of blood biochemical parameters of four species of vultures

Abstract

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.

Relationship between blood lead levels and clinical and physiological factors in Bonelli's eagle

“…In cases of chronic lead exposure, AST and CPK activities and uric acid concentration may be elevated (Puschner and Poppenga 2009); however, we did not observe any association between lead levels and these biochemical parameters in our study, probably because lead levels were moderate. The higher CPK values found in wild animals are probably due to physical restraint and handling stress (Heatley and Russell 2020, Chaprazov et al 2023, Paterlini et al 2023. During capture and handling of wild birds, it is easy to find occasional increases in AST and CPK due to muscle damage (Doussang andPalma 2018, Heatley andRussell 2020), so the value obtained could be affected by factors other than lead levels.…”