Veterinární medicína - In Press
A reproducible rat model for warfarin studies: Prothrombin time assessment with minimal blood using the CoaguChek XS and determination of an effective warfarin dosageOriginal Paper
ET Akyol, MT Hekim, M Erol
Warfarin research in rats is often challenged by methodological inconsistencies and large blood volume requirements. This study aimed to validate a refined, reproducible rat model for serial prothrombin time (PT) monitoring using the CoaguChek XS, in alignment with the 3R principles, and to determine an effective warfarin sodium dosage. Male Wistar albino rats received daily oral warfarin (0.125–0.750 mg/kg) for 5 days. PT was measured using the whole-blood CoaguChek XS and two laboratory plasma assays (Innovin, Thromborel S). Agreement was assessed using Bland–Altman and Passing–Bablok regression. The CoaguChek XS consistently yielded higher PT values than laboratory tests but showed strong agreement up to 25 seconds. A daily dose of 0.125 mg/kg resulted in a stable anticoagulant effect without mortality. Doses > 0.250 mg/kg were toxic, causing PT prolongation beyond the device’s range and death within 4–7 days after the initiation of treatment. In conclusion, the CoaguChek XS is a reliable tool for experiments requiring repeated measurements. Values remain reliable up to 25 seconds, and 0.125 mg/kg is a safe dose for short-term studies, effectively supporting animal welfare and the 3R principles.
Antimicrobial resistance in veterinary medicine: Mechanisms, regulation and control strategiesReview
P Matlakova, K Nedbalcova
Antimicrobial resistance (AMR) represents a major global threat to both human and animal health. Within the One Health framework, farm and wild animals serve as critical reservoirs of resistant bacteria and resistance genes, which can disseminate through food, water, and the environment. The excessive and inappropriate use of antibiotics in veterinary medicine exerts selection pressure that fosters the emergence and spread of antimicrobial resistance. Current mitigation strategies aim to reduce antibiotic consumption and promote prudent use through hygiene measures, vaccination, individualised therapy, pharmacokinetic-pharmacodynamic (PK/PD) dosing optimisation, and comprehensive AMR monitoring. European legislation (EU Regulations 2019/4 and 2019/6) provides stringent guidelines on antibiotic prescription, usage, and residue limits. In this context, antibiotic combination therapy represents a promising approach to enhance antimicrobial efficacy, broaden the antibacterial spectrum, and suppress the emergence of resistance by targeting multiple bacterial pathways simultaneously. In addition to developing new drugs, renewed focus on reviving older antimicrobial molecules – supported by updated PK/PD data and optimised dosing – could provide an effective alternative in combating multidrug-resistant pathogens.
Oral efficacy of controlled-release Doxycycline against Ichthyophthirius multifiliis infestation in SalmonidsOriginal Paper
Z Mikulkova, K Matejickova, J Motlova, P Ginterova, M Jerabek, L Pojezdal
Ichthyophthiriosis, caused by Ichthyophthirius multifiliis, is a major threat in the salmonid aquaculture. This study evaluated the efficacy of orally administered standard doxycycline and controlled-release doxycycline formulations in experimentally infected brook trout (Salvelinus fontinalis). Fish received medicated feed for 10 days starting seven days post-infection. Controlled-release doxycycline achieved the highest survival rate (84.2%), followed by standard doxycycline (73.7%), while no control fish survived after day 25 post infection. Both drug formulations eliminated trophonts from the skin and gills by 20 days post-treatment. Despite a 2.5-fold lower dietary dose, the controlled-release doxycycline reached a tissue concentration equivalent to ~32% of the standard doxycycline, with similar retention rates. Levels of doxycycline residues in water declined over time for both groups, indicating limited environmental release. These results demonstrate the effective mitigation of ichthyophthiriosis with orally administered doxycycline and the enhancement of antiparasitic efficacy and the reduction of drug load in the tissues and environment via controlled-release technology, supporting its potential as a sustainable medicated feed strategy in salmonid aquaculture.
Meloxicam blood levels are not affected by sex-related hormones in male and female goatsOriginal Paper
A Gokceoglu, Z Ozdemir Kutahya, GF Yarim, P Piner Benli, C Gokbulut
The present study aims to investigate the interaction between the non-steroidal anti-inflammatory (NSAID) drug meloxicam and sex hormones in seasonal polyoestrous male and female Saanen goats. It was hypothesised that sex hormones, both steroidal and non-steroidal, may influence the serum concentration of the lipophilic drug meloxicam. In the study, the relationship between plasma drug meloxicam concentration (μg/ml) and levels of Follicle-Stimulating Hormone (FSH), Anti-Müllerian Hormone (AMH), Testosterone, Estradiol (E2), and Progesterone (P4) was evaluated. For this purpose, six male and six female Saanen goats aged 1 year were intravenously administered a 0.5 mg/kg dose of meloxicam, and blood samples were collected at different time points (0, 5, 30 minutes, and 2, 8, 24, 48 hours) to obtain plasma and serum. Hormone levels were determined by ELISA method, following the manufacturer's instructions, and drug concentrations were measured by HPLC-UV technique. While the study found no direct correlation between meloxicam levels and sex hormones, significant differences in hormone levels by sex underscore the importance of considering sex-related physiological differences in veterinary pharmacology. These results will establish a scientific basis for future research on species- and sex-specific dosage adjustments.
An experimental challenge model for infecting African catfish (Clarias gariepinus) with Edwardsiella tardaOriginal Paper
I Toulova, V Vaibarova, I Papezikova, K Matejickova, I Mikulikova, H Novotna, M Palikova
Edwardsiella tarda is an important fish pathogen that causes outbreaks leading to significant losses in aquacultural species such as African catfish (Clarias gariepinus). In order to study host-pathogen interactions and design preventive strategies, it is essential to prepare a reliable experimental infection model. The aim of this study was to develop a reproducible immersion challenge model for E. tarda infection in C. gariepinus. The present study consisted of preliminary experiments and a main experiment evaluating the different routes of infection and the bacterial concentrations and exposure durations in an immersion bath. Preliminary experiments demonstrated that infection could be induced by either intraperitoneal injection or immersion bath, and that infection was more successful at higher concentrations. The main experiment involved two concentrations (10⁸ and 2×10⁸ CFU/ml) of immersion bath and two immersion durations (1 and 2 hrs), each repeated twice. The fish were monitored for clinical signs and mortality throughout the experiment and samples were collected on day 10 post-infection for haematological, immunological, and pathological assessment. High-dose immersion reliably induced infection, with disease progression depending on bacterial concentration and exposure duration. This established model is a practical and reproducible tool for future studies on the pathogenesis and immunity of C. gariepinus, as well as the use of immunostimulants and therapeutics.
The effect of Lactiplantibacillus plantarum probiotic supplement on rainbow trout challenged with Aeromonas salmonicidaOriginal Paper
I Mikulikova, Z Lepkova, H Bandouchova, J Blahova, I Papezikova, H Novotna, I Toulova, K Kobelkova, K Odehnalova, E Postulkova, M Radojicic, J Mares, D Mudronova, M Palikova
Two probiotic (Lactiplantibacillus plantarum) supplementation strategies (continuous and cyclic) were evaluated for their ability to enhance resistance of rainbow trout (Oncorhynchus mykiss) to Aeromonas salmonicida infection. Neither of these strategies demonstrated an improvement in post-challenge survival. Instead, cyclic administration resulted in a significantly higher mortality rate (73%) compared with continuous supplementation (52%) and the control group (46%). One week post-challenge, most haematological, plasma biochemical and immune parameters showed no significant difference between treatments, though fish receiving cyclic supplementation did exhibit a reduced lymphocyte count. However, three weeks post-challenge, this same group showed a significant decrease in total phagocyte number and in proportion of phagocytes within white blood cells. IgM concentrations were significantly lower in both probiotic-supplemented groups compared with the control. In the cyclic group, a reduction in interleukin-10 and an elevation in total protein levels were also observed. Microbiome analysis of gut content three weeks post-challenge revealed a marked decline in microbial diversity in both probiotic-treated groups. These findings indicate that, under the conditions of the experiment, probiotic supplementation did not provide protection against A. salmonicida infection and that cyclic administration may disrupt immune homeostasis and intestinal microbial stability, ultimately compromising host resilience.
The contribution of polymer additives to microplastic toxicity: A long-term study with Oncorhynchus mykiss exposed to polystyrene microparticles with different hexabromocyclododecane contentOriginal Paper
N Hodkovicova, J Blahova, K Stastny, M Charvatova, A Franc, F Tichy, L Sedlackova, J Mares, M Faldyna, Z Svobodova
Although microplastic toxicity in fish has been extensively studied, the role of polymer additives remains insufficiently understood. This study investigated the combined effects of polystyrene (PS) microplastics and the brominated flame retardant hexabromocyclododecane (HBCD) on the health of rainbow trout (Oncorhynchus mykiss) following six weeks of dietary exposure. Fish were exposed to PS particles with varying HBCD content (0.0 mg/g – PS-HBCDfree, 0.2 mg/g – PS-HBCDlow, 1.0 mg/g – PS-HBCDhigh) or to HBCD alone (HBCDonly). The combination of PS and HBCD induced the most pronounced biological responses at molecular, biochemical and histological levels. In the liver, oxidative stress and upregulation of pro-inflammatory cytokines (il8, il2) were observed, together with decreased glutathione reductase activity and increased catalase expression, indicating an imbalance in antioxidant defence. Histopathology confirmed liver dystrophy and renal lesions, while elevated vitellogenin expression suggested endocrine disruption. Although HBCD accumulation was confirmed only in the HBCDonly group, the polymer-bound form caused comparable physiological alterations, supporting its contribution to combined toxicity. Overall, the study demonstrates that PS microparticles can act as vectors enhancing the bioactivity of embedded additives such as HBCD, resulting in complex multi-organ effects and emphasising the importance of assessing additive–polymer interactions when evaluating the environmental risks of microplastics.
Effect of praziquantel´s 24-hour bath on haematological and biochemical profile and selected parameters of oxidative stress in grass carp (Ctenopharyngodon idella)Original Paper
R Dobsikova, P Marsalek, J Velisek, J Blahova
This study assessed the effect of a 24-hour bath with praziquantel (2 and 4 mg/l) on grass carp (Ctenopharyngodon idella) by monitoring haematological parameters, plasma biochemical profile, and oxidative stress indices. Fish were sampled at 24-, 48-, 72-, and 96-hours post-exposure (hpe). Haematological analysis revealed a significant increase (P < 0.05) in white blood cell count immediately after treatment at both concentrations, with no subsequent changes. Within the plasma biochemical profile, a significant decrease (P < 0.05) was observed only in chloride (24 hpe at 2 mg/l; 72 hpe at both concentrations) and in magnesium (48 hpe at 2 mg/l). Oxidative stress responses indicated that the gill was the most responsive tissue. In the gill, catalase and glutathione S-transferase activities increased significantly (P < 0.05) at 48 hpe at 4 mg/l. Lipid peroxidation in the gill decreased at 48 hpe but increased at 72 hpe following exposure to 4 mg/l. In the hepatopancreas, glutathione peroxidase activity significantly decreased at 48 hpe at 2 mg/l. In plasma, significant changes (P < 0.05) were detected only in ceruloplasmin activity, which showed a decrease at 72 hpe at 2 mg/l group. These findings provide essential baseline data supporting the potential future application of praziquantel in aquaculture.
Drugs and products in beekeeping: efficacy and perspectives of natural alternativesReview
I Szabo, L Sabova, R Sabo, M Sucik
Honeybee health is a key factor in sustainable apiculture, with the most significant colony losses attributed to the mite Varroa destructor and microsporidia of the genus Nosema spp. The aim of this review article is to summarise current knowledge on the use of pharmaceuticals and preparations in the prevention and treatment of these diseases and to highlight promising alternatives to synthetic acaricides. Commonly used active substances such as amitraz and pyrethroids show decreased efficacy in many countries due to the development of resistance. Therefore, organic acids (formic, oxalic, and lactic acids), essential oils, and plant extracts are increasingly applied as environmentally friendly, residue-free alternatives. Some plant preparations and extracts have been shown to be effective against Nosema ceranae. In addition to therapeutic interventions, the importance of preventive measures and immune support through supplements containing vitamins, amino acids, and probiotics is emphasised. The article highlights the need for integrated bee health management combining pharmacological, natural, and biotechnological approaches to limit resistance development, minimise residues in bee products, and promote overall colony vitality.
In vitro comparison of anthelmintic efficacy across Gyrodactylus speciesOriginal Paper
M Ondrackova, J Kolarova, K Skocovska
Gyrodactylosis, caused by monogenean parasites of the genus Gyrodactylus, poses a significant threat to aquaculture, particularly under intensive farming conditions. This study evaluated the in vitro effectiveness of three veterinary anthelmintics - fenbendazole (FBZ), levamisole hydrochloride (LHC), and ivermectin (IVM) - against four Gyrodactylus species collected from wild cyprinid hosts. Parasite survival was monitored over 48 hours at 6–7 °C. LHC showed the highest efficacy at both tested concentrations (30 and 50 mg/l), achieving near-complete mortality within 8 hours. FBZ and IVM were significantly less effective, with 23% and 33% of parasites surviving, respectively. Species-specific differences in drug susceptibility were observed, particularly with FBZ and IVM, with G. carassii showing consistently higher sensitivity than G. laevis, G. rutilensis, and G. vimbi. Lower water temperatures probably contributed to reduced drug efficacy and prolonged parasite survival. These findings highlight the importance of species-level evaluation and temperature considerations when selecting anthelmintic treatments for gyrodactylosis. In vitro testing under controlled conditions offers valuable insights into parasite susceptibility and complements in vivo approaches. Further research incorporating broader parasite diversity, temperature ranges, and pharmacological profiles is recommended to optimise treatment strategies in aquaculture.
Protective effect of Loranthus tanakae Franch. & Sav. on allergic asthma induced by ovalbuminOriginal Paper
S-H Park, S-W Pak, W-I Kim, B-R Jin, Y-K Cho, T-W Kim, J-W Ko, J-S Kim, J-C Kim, A Yeong Lee, I-S Shin
Allergic asthma is a widespread disease with elevated eosinophil levels. Although corticosteroids are widely prescribed for allergic asthma, numerous patients experience limited sensitivity and side effects. Loranthus tanakae Franch. & Sav., a traditional herbal plant, has anti-inflammatory and antioxidant properties in pulmonary inflammation caused by Asian sand dust and cigarette smoke condensate. To assess protective effects of L. tanakae, we examined the influence of L. tanakae ethanol extract (LTE) in ovalbumin (OVA)-induced asthma. Mice received intraperitoneal sensitization with OVA, and challenged using OVA inhalation. LTE was consecutively orally gavaged for 6 days. Following sacrifice, bronchoalveolar lavage fluid (BALF) and lung tissue was analyzed. LTE treatment considerably dropped inflammatory cell counts, proinflammatory cytokines in BALF, and immunoglobulin E as opposed to the OVA group, along with a reduction in airway hyperresponsiveness. LTE also improved airway inflammation and suppressed mucus hypersecretion within lung tissues. Additionally, expression of MMP-9 and activation of Erk, JNK, and p-38 were notably diminished in the LTE groups. This study revealed that reduced airway inflammation in OVA-induced asthma via suppressing MMP-9 and mitogen-activated protein kinase associated factors. Consequently, our findings demonstrated that LTE is suggested as a potential remedy for allergic asthma.
From grain to forage: A decade of mycotoxin contamination in ruminant feed in the Czech Republic (2013-2023)Original Paper
J Cahova, L Kvasnickova, J Illek, T Palenik, A Staffa, V Vlasakova, Z Svobodova, L Ravonjison, M Svoboda
This study is based on analytical data focusing on mycotoxin contamination in ruminant feeds in the Czech Republic over a ten-year period (2013—2023), specifically deoxynivalenol (DON), zearalenone (ZEN), T-2 toxin (T-2/HT-2), and ochratoxin A (OTA). Analyses were performed in accredited State Veterinary Institutes using validated immunochemical and chromatographic methods. Samples included forage and concentrate feeds for dairy cows, calf feed and fattening cattle feed. Across the monitoring period, DON was detected within higher concentration ranges, reflecting the susceptibility of field crops to Fusarium infection under local environmental conditions. Forage feeds showed significantly higher concentrations of DON (472.6 ± 13.2 µg/kg), ZEN (61.7 ± 4.4 µg/kg), and T-2/HT-2 toxin (36.2 ± 2.7 µg/kg) than concentrates for dairy cows (P < 0.05). Additionally, ZEN levels differed significantly between concentrates for dairy cows (17.1 ± 2.3 µg/kg) and calf feed (16.2 ± 3.3 µg/kg) (P < 0.05). Although mycotoxin concentrations generally remained below recommended limits, a small proportion of samples exceeded guideline values for DON (0.13%) and ZEN (0.56%). These findings highlight the importance of continued monitoring and preventive strategies to manage mycotoxin risks.
Comparison of the effect of Mospilan SP and its active substance on Artemia franciscanaOriginal Paper
M Falis, K Benova, M Spalkova, L Leskova
Contaminants formed after the use of pesticides raise concerns for human health and aquatic ecosystems, i. a. due to their high persistence in surface waters and their further migration to other components of the environment. In our study, we compared the effect of the preparation Mospilan SP and its active substance acetamiprid on the aquatic crustacean Artemia franciscana. For Mospilan SP LC50 after 120 hours was 367.44 mg/l, and after 144 hours 102.82 mg/l. For the active substance acetamiprid LC50 after 144 hours was 148.04 mg/l and after 168 hours 28.84 mg/l. The commercial preparation Mospilan SP showed a significant suppressing effect on the measured morphological parameters (body length, body width, intestinal diameter, and intestinal wall thickness) which were at a statistically significant level after 10 days of exposure. When comparing the changes after the application of the preparation and the active substance itself, it is impossible to confirm the same effect on the morphological parameters in given time intervals.
Impact of histological and molecular subtype on the potential therapeutic effect of Buparlisib in canine mammary gland tumoursOriginal Paper
A Baykal Ugur, G Guney Eskiler, O Turna
This study aims to evaluate the response of primary cells to Buparlisib, a PI3K inhibitor, at varying concentrations and exposure durations across different histological and molecular subtypes of CMGTs, and to assess PI3K/Akt/mTOR pathway activity by measuring Akt and mTOR expression. Three carcinomas (C), three sarcomas (S), and two carcinosarcomas (CS) tumours were collected from the dogs. The primary cells were produced from tissues and treated with Buparlisib at different doses. Subsequently, the WST-1 assay, Annexin V, and AO/PI staining were performed sequentially to evaluate the effects of Buparlisib. PI3K/Akt/mTOR signalling pathway inhibition was revealed at the gene level in C, S, and CS cells following 5 µM Buparlisib treatment by RT-PCR analysis. Our results demonstrated that C1 and C2 (basal-like) cells were more sensitive than C3, CS1, and CS2 cells (Luminal A) upon Buparlisib treatment. Liposarcoma S2 cells responded more to Buparlisib than undifferentiated S cells (S1 and S3). Buparlisib also induced apoptosis and inhibited Akt and mTOR mRNA levels in CMGT cells (P < 0.05). A higher rate of apoptotic cell death was observed in the C histological subtype and basal-like cells, with 62.9 ± 0.8% apoptosis in C1 and 79.1 ± 0.3% in C2. The efficacy of Buparlisib was more pronounced in C2 basal-like CMGT cells and liposarcoma S2 cells with the downregulation of Akt and mTOR mRNA levels (P < 0.001). Therefore, PI3K inhibitors could be used to treat CMGT, particularly the basal-like molecular subtype.