Donkey milk is highly valued for its unique nutritional characteristics and hypoallergenic properties. However, limited data exist on its mineral composition and potential contaminants. This study aimed to comprehensively analyze the concentration of selected essential and toxic elements from Banat and Balkan donkey breeds reared under extensive organic conditions (free-range) across different seasons. The focus was on determining the concentrations of essential minerals and trace elements (Ca, P, Na, K, Mg, Zn, Cu, Se), and potentially toxic elements (As, Pb, Hg, Cd). Samples were collected monthly over one year, with nine pooled samples per season. Mineral elements were determined using a validated ICP-MS method. The mineral content ranges (mg/kg) were Ca (588.9–744.4), P (355.6–533.3), Mg (71.1–84.4), K (444.4–711.1), Na (355.6–444.4), with trace elements (mg/kg) including Zn (2.06–2.21), Cu (0.31–0.68), and Se (0.02–0.05). Potentially toxic elements were within safe limits, with the exception that Pb levels exceeded permissible limits in two samples. Statistically significant seasonal variations were observed for Ca, P, K, As, and Cu. Donkey milk from both breeds was rich in minerals and low in contaminants. This research highlights the need for further studies on the nutritional and safety aspects of donkey milk.

The Domestic Balkan and Banat donkey (Equus asinus asinus) are native donkey breeds primarily raised in the Special Nature Reserve 'Zasavica', Serbia. The study's objective was to analyze the composition of donkey's milk during the lactation period (12th to 30th week of lactation), regardless of the donkey's breed. The investigated donkey milk composition is characterized by a low content of dry matter, protein and fat and a high amount of lactose, compared to the milk of other dairy animals. The study revealed that content of dry matter ranged from 7.20 to 9.52%, fat ranged from 0.10 to 1.00%, protein ranged from 1.17 to 2.07%, lactose ranged from 4.52 to 6.71%, ash ranged from 0.28 to 0.50% and pH ranged from 6.82 to 7.46. Dry matter, fat, and ash content progressively lowered during lactation, with some oscillations. Milk protein and lactose content were not affected during the lactation stage. The pH value increased progressively during lactation with slight oscillations during the 18th and 21st week of lactation. Statistically significant differences between lactation weeks were established only for lactose content and pH values.

Biocompatibility of materials is one of the most important conditions for their successful application in tissue regeneration and repair. Cell-surface interactions stimulate adhesion and activation of macrophages whose acquaintance can assist in designing novel biomaterials that promote favorable macrophage–biomaterial surface interactions for clinical application. This study is designed to determine the distribution and number of macrophages as a means of biocompatibility evaluation of two newly synthesized materials [silver/poly(vinyl alcohol) (Ag/PVA) and silver/poly(vinyl alcohol)/graphene (Ag/PVA/Gr) nanocomposite hydrogels] in vivo, with approval of the Ethics Committee of the Faculty of Veterinary Medicine, University of Belgrade. Macrophages and giant cells were analyzed in tissue sections stained by routine H&E and immunohistochemical methods (CD68⁺). Statistical relevance was determined in the statistical software package SPSS 20 (IBM corp). The results of the study in terms of the number of giant cells localized around the implant showed that their number was highest on the seventh postoperative day (p.o.d.) in the group implanted with Ag/PVA hydrogels, and on the 30th p.o.d. in the group implanted with Ag/PVA/Gr. Interestingly, the number of macrophages measured in the capsular and pericapsular space was highest in the group implanted with the commercial Suprasorb^© material. The increased macrophage number, registered around the Ag/PVA/Gr implant on 60th p.o.d. indicates that the addition of graphene can, in a specific way, modulate different biological responses of tissues in the process of wound healing, regeneration, and integration.

Hepatitis E virus (HEV) is the causative agent of acute hepatitis E infection in humans. Two epidemiological patterns of the disease exist—endemic and sporadic. Genotypes 1 (HEV-1) and 2 (HEV-2) are transmitted through contaminated water and are responsible for the outbreaks of many large-scale epidemics in developing countries of Asia and Africa. Genotypes 3 (HEV-3) and 4 (HEV-4) have zoonotic potential and cause sporadic cases and small outbreaks in high-income countries. The first case of HEV infection in swine was confirmed in 1997 and later detected in other animal species. The aim of this study was to investigate the seroprevalence of HEV infection in pig farms in Vojvodina province, Serbia. Three hundred blood samples were collected from five different categories of pigs from 3 different farms on the territory of the South Bačka district in Vojvodina (Serbia). The analyses were conducted by in-house ELISA, while the western blot method was used as a confirmatory test for doubtful results. The presence of HEV IgG was detected on all three examined farms. The established seroprevalence in Farm A was 37%, 31% in Farm B, and 54% in Farm C. The mean seroprevalence for all farms was 40.66%. A higher seroprevalence was found in fatteners compared to younger categories of pigs. We concluded that HEV is widespread on pig farms with intensive management. Further analyses should be conducted with the aim of implementing a surveillance program to prevent possible human infection.

Background: Canine skin and ear infections are common in small-animal practice and increasingly complicated by multidrug resistance (MDR), yet data from Serbia are limited. This study aimed to describe the bacterial etiology and antimicrobial resistance patterns in canine otitis externa and pyoderma. Methods: We retrospectively reviewed laboratory records from the Clinical Bacteriology and Mycology Laboratory, Faculty of Veterinary Medicine, University of Belgrade (January 2017–August 2024). A total of 422 non-invasive swabs from clinically ill dogs were included (ears: n = 210; skin: n = 212). Bacterial identification used conventional methods and commercial systems, and disk-diffusion susceptibility testing followed CLSI/EUCAST guidance. Methicillin resistance in staphylococci was assessed by cefoxitin/oxacillin screening; MRSA was confirmed by PCR and PBP2a detection. Resistance trends were compared between 2017–2020 and 2021–2024. Results: The leading pathogens were Staphylococcus pseudintermedius (ears 48.1%; skin 79.7%) and Pseudomonas aeruginosa (ears 29.1%; skin 7.6%). Staphylococci showed high resistance to macrolides, clindamycin, tetracycline, and first-line β-lactams (amoxicillin–clavulanate, cephalexin), with the highest susceptibilities to amikacin, florfenicol, and rifampicin. P. aeruginosa remained most susceptible to amikacin, polymyxin B, and imipenem. Between the two periods, S. pseudintermedius resistance increased to amikacin, fusidic acid, and cephalexin, while resistance to florfenicol decreased. P. aeruginosa resistance to imipenem increased. The prevalence of methicillin-resistant S. pseudintermedius (MRSP) was 27.4% (74/270). MDR S. pseudintermedius and MDR P. aeruginosa were identified in 38.5% and 53.3% of isolates, respectively. One isolate of each species was resistant to all tested drugs. Conclusions: These findings confirm high levels of antimicrobial resistance in major canine skin and ear pathogens and emphasize the need for susceptibility-based therapy, rational antimicrobial use, and ongoing surveillance in small-animal practice.

The ethical dilemmas of using animals as in vivo models in preclinical and clinical examinations have been increasingly present in recent decades. Small laboratory animals (rats, rabbits) will continue to be used because they are cost-effective and permit the formation of statistically testable cohort groups; a task that, for financial, maintenance and care reasons, is almost prohibitive for larger animals. Technological advances in the production of new biomaterials for clinical use are enormous, but screening tests and methods used to assess biocompatibility lag behind these advances. The assessment of biological responses is slow and based on millennial recovery mechanisms in eukaryotic organisms. Therefore, the goal of researchers in this field is to re-evaluate old methods of biocompatibility assessment and introduce new methods of evaluation, especially for in vivo testing. In that sense, a revision of the ISO standards was planned and conducted in 2017, which insisted on cytotoxicity testing in cell lines and produced concrete proposals on how biocompatibility should be quantified. In vivo biocompatibility evaluation of biomaterials used for soft tissue recovery commonly utilises rats. Rabbits are recommended for implants used for hard tissues, because of the rabbit?s size, the possibility of implanting the biomaterials on a larger bone surface, and because of the peculiarities of rabbit bone tissue that favours rapid recovery after bone defects and enables easy reading of the results