Nikola Krstić

Evolutionary and paleogeographical effects on the distribution of the Triturus cristatus superspecies in the central Balkans

A synthesis of all known data on the crested newt group assigns the Balkan peninsula as the center of origin or, at least, the area where the basic lineage of its species was limited in the late Miocene. According to the recent literature, the geological structure of the Balkan region changed considerably during the Tertiary. These geological processes could have had a considerable impact on crested newt divergence and on the recent distribution of species. Using the number of rib-bearing vertebrae (RBVN), recently suggested as a simple and powerful tool for distinguishing four taxa of the T cristatus superspecies, we analysed 36 population samples collected all over former Yugoslavia. The hypothesised recent distribution of the crested newt species, based on frequency distribution of RBVN, appears to correspond well to neotectonic events in the past.

Skin and skeletal system lesions of european pond turtles (Emys orbicularis) from natural habitats

Water pollution is known to play an important role in the pathogenesis of plastron, carapace and skin diseases of turtles. In this study, a total of 150 European pond turtles (Emys orbicularis) of different age and both sexes, originating from natural habitats in Serbia, were examined for morphological changes of the skin, plastron, carapace and skeletal system. The turtles were taken out from their natural habitats in Lake Ludas, Lake Palic and Lake Tresetiste. After artificial hibernation, they were subjected to detailed examination, sampled and treated, and finally returned into their natural habitat. Biopsies from the skin and shell were subjected to histopathological examination and microbiological analysis. X-ray scanning was also performed to detect changes in the skeletal system. Macroscopic changes of the skin, most frequently degenerative, inflammatory or neoplastic diseases, were diagnosed in 49.33% of the turtles examined. Dermatitis of different origin and form was the most prominent histopathological finding (28.00%). In the plastron, inflammatory and degenerative processes were frequently found. Osteopathy and mechanical injuries were the dominant findings. Macroscopic changes of the plastron, carapace and skeletal system were diagnosed in 67.33% of the turtles examined. Using X-ray scanning, generalised osteopathy, anomalies and malformations of different aetiology were also diagnosed on the tail and legs. Microbiological examinations showed the presence of a variety of bacterial and fungal agents, either primary pathogens or potential polluters, which invaded the skin and shell, or were present in cloacal swab samples. Bacterial infection was diagnosed in 76.66% of the turtles, first of all in those with skin and shell necrosis. Mycoses were diagnosed in 33.33% of the animals.

Incidence patterns of ectodermic lesions in wild populations of Common Wall Lizard (Podarcis muralis)

Skin lesions frequently present in adult lizards may be due to a variety of causes, both physical and infectious, including excessively high humidity and environmental temperature, malnutrition, concurrent disease etc. On the other hand, skin lesions in lizards could be simple evidence of various behavioural patterns and biotic interactions. However, studies on frequencies of dermal lesions and their anatomical and environmental correlates in lacertid lizards are rare. Here, we use Podarcis muralis to analyse the relations between occurrence of ectodermal lesions and three possible indicators of environmental stress (body condition index – BCI, infestation by ticks and tail condition) by evaluating differences among local populations at uni- and multivariate level. Our results showed that BCI, together with body size and sexual size dimorphism, varied between populations but had no direct influence on the presence of lesions. Males had higher frequencies of lesions and ticks but lower frequencies of broken tails than females. All three parameters varied between sites likely due to differences in predation/parasite exposures and agonistic interactions with conspecifics between sexes and populations. Results of multivariate analyses suggested that the occurrence of lesions is decoupled from the other morphological stress indicators. Detected associations indicated that relations between presence of lesions and other analysed variables are rather complex. Directions for further research on ectodermal lesions in lacertid lizards are provided.

Radiological assessment of apex formation following use of hydroxyapatite

The treatment of pulp in teeth with incomplete apex formation is still a clinical challenge. In addition to the most widely used medication for this purpose, calcium hydroxide, other materials have also been tested. Following the use of synthetic biomaterials for restoring bone tissue, and considering their recognized biocompatibility and bioconductivity, our intention was to explore the possibility of using synthetic biomaterials in the endodontic treatment of permanent teeth with incomplete apex formation. The aim of this study was to observe the effectiveness of hydroxyapatite in apexogenesis of young permanent teeth. In this study a 100 µm synthetic hydroxyapatite material, Beohap (HAP) powder, was applied to 24 teeth in 3 dogs of 5.5 months of age, after incomplete root development was established on radiographs. The treated teeth were radiographed monthly and the radiographs compared with those of the corresponding teeth on the other side of the jaw until completion of apex growth. The tested teeth were divided into three groups according to the method of treatment: the first was direct pulp capping, the second was amputation of the pulp at the enamelcement junction and the third was high amputation at the radiographically identified point of root growth. On the basis of radiographic analysis, apex formation was successful in all test groups, with no significant differences between the three groups and the controls (Fishers and χ 2 test). Deformities of the root apex were observed in two teeth (25%) in the third group.

Testing the effect of different electrotherapeutic procedures in the treatment of canine ankylosing spondylitis.

This paper presents the results of studies on the effects of suppression of chronic pain by currents with low (TENS), medium (Intf) and high (MT) frequencies, in dogs with ankylosing spondilytis. Prior to imaging diagnostics the dogs were clinically observed, trias was estimated, as well as habitus, neurological signs and degree of pain. After a 10 day treatment it was clear that all three treatments resulted in a significant decrease of pain at rest, during activity or during palpation. TENS currents have shown the highest degree of effect. All treated animals have shown improved motility after a few months of therapy. Despite the fact that all animals had an improved clinical picture none of the applied currents resulted in a complete loss of limping. Dogs treated with Intf currents displayed a decrease in muscular atrophy. Motility of the coxofemoural joint was most evident in the group treated with microwaves.

Clinical study on the influence of hydroxyapatite on apexogenesis in monkeys.

Management of the affected pulp in teeth with incomplete root formation is still an issue. Calcium hydroxide and other materials have been employed for this purpose to a greater or lesser success. Bioceramic materials are in the last decades well established in a number of different medical fields. Having its constituents the same as those of the unorganic portion of bone tissue, hydroxiapatite (HAP), one of the two forms of calcium-phosphate ceramics, is already accepted in endodontic treatment of teeth with completed root formation. The aim of this study was to examine apexogenesis in teeth with immature roots, following the use of HAP on their affected pulp. Examination was performed on eight young monkeys (Cercopithecus Aethiops) with incomplete root development. The 100 _m synthetic HAP material was applied on 32 teeth divided into two groups of 16 teeth each. In one group teeth underwent pulpotomy, in the other high pulpotomy. Evaluation of root growth was recorded from radiographs (pre-treatment, 3 and 12 months following treatment) and by Demjrians scale for dental maturity and tooth age determination. On the basis of radiographic analysis, immature teeth with affected pulp treated with HAP, both with pulpotomy and high pulpotomy, reached the same stage of root development as control teeth in 50% of cases at 3-months radiographic assessment. After 12 months all tested teeth had the same rate of root development as control teeth, except for 1 of 8 with high pulpotomy. Dentinal bridge was radiographically visible in 50% and 87.5% of pulpotomized teeth after 3 and 12 months, respectively. Neither obliteration of the root canal, presence of denticles nor the presence of deformities in the periapical region were found in any of the observed teeth.

Spavin in red deer: A case study from the Early Neolithic Blagotin, Serbia

Pathological modifications are rarely observed in the remains of wild animals from archaeological sites. We present one such specific, pathological change - a case of spavin in a red deer specimen from the Early Neolithic site of Blagotin, in central Serbia. The left tarsal joint presented proliferative new bone formation, which was analyzed macroscopically, then subjected to X-ray and computed tomography (CT) imaging. We assume that the initial degenerative changes in this red deer tarsal joint were probably caused by ageing, although the environment may have likely contributed to the progression of the disorder. Spavin usually results in stiffness of the joints and in lameness, perhaps contributing in the animals capture by Neolithic hunters. This case is important in that it demonstrates that spavin is not necessarily a consequence of riding or traction work.

X-ray diagnostics of most common periodontal diseases in dogs and cats.

Dental diseases in dogs and cats are of increasing importance in veterinary practice. If not diagnosed and treated on time, they can significantly affect the quality of life and pet health as well. Roentgenography of orofacial system, as a part of veterinary dentistry, is an important diagnostic tool that provides insight into diseases and irregularities of the teeth, shows macrostructure of bone parts, and also may indicate the etiology and genesis of various pathological conditions of the teeth. The objective of this paper is to point out to most common pathologies which small animal veterinary dentistry daily meets, as well as to foster the systematic development in this area in order to find more quality to both diagnostic and therapeutic procedures.

Efficiency of modified therapeutic protocol in the treatment of some varieties of canine cardiovascular dirofilariasis

Abstract The paper presents clinical diagnostic approaches and therapeutic effects of a specific protocol for the treatment of dogs with cardiovascular dirofilariasis in the Belgrade City (Serbia) territory. The study involved 50 privately owned dogs of different breeds, gender, and age, all showing signs of cardio - respiratory disorders. In addition to a general physical examination, blood tests were done to detect microfilaria and adult forms, and X-ray, ECG, and echocardiography were performed as well. At the first examination, 34 out of 50 examined dogs were positive for microfilaria and adult forms. Because of a lack of drug used as „the golden standard“ in dirofilariasis treatment, it involved a combination of doxycycline (10 mg/kg) and ivermectin (6 μg/kg) supported with Advocate - Bayer spot-on. After six months, the first control was performed while continuing treatment with the aforesaid protocol, and the second control was performed after 12 months. Of the 34 treated dogs, all were negative for microfilaria, as early as after the first six months of the treatment (100%). One dog was positive for adult forms of the parasite after six and 12 months. In echocardiography and X-ray examination after 12 months, six dogs showed evident chronic changes. At controls conducted at sixth month and at one year, the implemented therapy was successful in 97.05% (33/34) of primarily infected dogs.

Manifestations of joint disease of domestic carnivores in X-ray view

Changes caused by joint diseases that are manifested in X-ray are very diverse. Some of them are present in all arthroparthies while some are specific to certain diseases. For all the arthropathies it is specific that the duration of a disease significantly influences the presence and intensity of radiological changes. In this paper there analyzed in detail some basic radiological joint diseases manifestations such as: distension of the joint capsule, change of size (width) of the joint space, change of position of corresponding bones within the joint, change in quality of subchondral bone, the appearance of intra-articular mineralization and calcified structures, as well as the presence of perichondral and periarticular bone proliferations. Beside that, there are described in detail arthropathies of different etiology. [Projekat Ministarstva nauke Republike Srbije, br. 175061]