Antimicrobial (AM) resistance is a growing threat in human and veterinary medicine, spreading across species and perceived as One-Health issue. Prudent use of AM products is essential in mitigating this risk in both human and veterinary medicine. Farm veterinarians, responsible for prescribing appropriate AM and offering advice to farmers on their proper usage, are regarded as key players in the livestock industry. An online survey of farm veterinarians (n = 1,531) was conducted to assess their educational experience, beliefs, current status of prescription, practical behavior, and self-efficacy regarding the prudent use of antimicrobials (PUA). The data from 170 respondents were analyzed using descriptive statistics, regression and mediation analysis. Participants chose AM based on their experiences, academic resources, and peer veterinarians. Approximately 77% did not routinely conduct antibiotic-susceptibility-test. Most participants believed in the importance of PUA and the role of veterinarians to reduce AM resistance, but they reported a lack of awareness among farmers and insufficient national support interfere with their practical behavior with regard to PUA. Half of the participants had PUA-education, and 78.6% reported that education had a positive impact on their behavior with PUA. Self-efficacy partly mediates the relationship between belief and behavior for PUA, which accounted for 23.77% of the total effect that beliefs have on behavior for PUA. The findings of the study show that enhancing veterinarians’ abilities to practice and their self-efficacy through education tailored to the current status of farms can contribute to the reduction of AMs in the livestock sector.

This study was conducted to investigate tiamulin (TML) residues in the edible tissues of orally dosed broiler chickens and to re-establish the withdrawal time (WT). Thirty-six healthy Ross broiler chickens were administered 0.5 (TML-1) and 2.5 kg (TML-2) per ton feed, respectively, of the drug containing TML 78 g/kg for 10 days. Twenty-four tissue samples were collected from 6 chickens in each of the TML-1 and TML-2 groups on 0, 1, 3, and 5 days after drug administration, respectively. The residual concentrations of TML were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The correlation coefficient of the calibration curves was 0.9978 to 0.9998, and the limits of detection and the limits of quantification (LOQ) were in the range of 0.03 to 0.06, and 0.1 to 0.2 µg/kg, respectively. Recoveries ranged between 89.0% to 116.7%, and the coefficients of variation were less than 13.9%. After the drug administration, TML in the TML-1 and TML2 groups was detected above the LOQ in 1 and 6 samples of liver, respectively, at day 0, and in 1 liver sample from both groups on day one. At 3 days after administration, TML was detected below the LOQ in all samples of TML-1 and TML-2. The calculated WT of TML in both TML-1 and TML-2 using the WT calculation program WT 1.4 was 0 days. In conclusion, the developed analytical method is suitable for detection, and the calculated WT of TML in poultry edible tissues is shorter than the current recommended WT of 7 days for TML in broiler chickens.

Rehabilitation treatments after orthopedic surgery promote postoperative healing in humans. In veterinary medicine, there is increased interest in rehabilitation treatments because they are potentially beneficial to animals in the post-operation period. This study examined the effectiveness of rehabilitation treatment in dogs that underwent orthopedic surgeries, including femoral head & neck ostectomy (FHNO) and medial patellar luxation treatment (MPLT). The group that received the rehabilitation treatment after FHNO (1.88 weeks) showed a significantly shorter recovery length of 6.62 weeks compared to those that did not receive the treatment (8.50 weeks). The other group that received the rehabilitation treatment after MPLT (4.38 weeks) showed a significantly shorter recovery length of 5.01 weeks compared to those that did not receive the treatment (9.39 weeks). For the qualitative evaluation, the types and frequencies of rehabilitation treatments were monitored. The rehabilitation programs used frequently were heat therapy, laser therapy, passive range of motion, exercise therapy, and aquatic therapy. A standard rehabilitation program after hindlimb surgery was suggested based on the quantitative and qualitative investigation. The results add additional evidence that showed the beneficial effects of rehabilitation treatments in dogs.

This study investigated dexamethasone (DXM) residues in the milk from intramuscularly dosed dairy cows and established the withdrawal time (WT) of DXM in milk. Eighteen healthy Holstein cows were injected with 20 (DXM-1) or 40 mL (DXM-2) of a drug containing 1 mg/mL of DXM. After administering DXM, milk samples were collected from all cows at 12-hour intervals for five days. The DXM residue concentrations in milk were determined by liquid chromatography-tandem mass spectrometry. The correlation coefficient of the calibration curve was 0.9966, and the limits of detection and quantification (LOQ) were 0.03 and 0.1 μg/kg, respectively. The recoveries were 97.0% to 104.0%, and the coefficient of variations was less than 7.22%. After treatment, DXM in DXM-1 was detected above the LOQ in two milk samples at 36 hours and below the LOQ in all milk samples of DXM-2 at 48 hours. Using the WT calculation program WT 1.4, the withdrawal periods of DXM-1 and DXM-2 in milk were established to be two days. In conclusion, the developed analytical method is sensitive and reliable for detecting DXM in milk. The estimated WT of DXM in bovine milk is shorter than the current milk WT recommendation of three days for DXM in lactating dairy cows.

Eight rabbits exhibited head tilt and subsequently died. At necropsy, three rabbits had crusty deposits in ears and four had reddish lungs. The main histopathological features were severe diffuse suppurative meningoencephalitis (75.0% of rabbits), fibrinopurulent pneumonia (37.5%), and otitis externa (37.5%). Pasteurella multocida (P. multocida) was isolated from brains, ears, and lungs. The capsular serogroups of the isolates were untypable. Based on histopathological features and bacterial analysis results, the rabbits were diagnosed as P. multocida infection. P. multocida infections might result in considerable economic loss in commercial rabbit production facilities in Korea.

Althaea rosea has been used in traditional Chinese medicine to treat numerous diseases, but no studies have investigated its anti-influenza properties to date. In this study, we investigated the anti-influenza effects of Althaea rosea. BALB/c mice orally pretreated with Althaea rosea (200 킠, 0.1 mg/mL concentration in phosphate-buffered saline) and followed by infection of influenza A virus nasally showed higher survivability and lower lung virus titer against divergent subtypes of influenza A virus infection. We also found that oral administration of Althaea rosea elicited antiviral innate immune responses in serum, bronchoalveolar lavage fluid, small intestinal fluid, and the lungs. Taken together, these findings suggest that aqueous extracts of Althaea rosea are a potential candidate for use as an anti-influenza drug.

Canine mammary tumors are among the most frequently observed cutaneous tumors in female dogs. Cancer stem cells (CSCs), referred to as tumor-initiating cells, are thought to have properties similar to normal stem cells such as the ability to self-renewal and to differentiate into various cell types. Biological understanding of CSCs and the critical pathways involved in their maintenance are important in research and therapy for mammary tumors. We conducted the present study on sphere formation from REM134 cells by using methylcellulose to produce tumorspheres on a large scale and compared the specific markers of the spheres-formed and plating-cultured REM134 cells. The results revealed that the tumorspheres cultured in methylcellulose had higher seeding density and improved morphology compared to those produced in normal sphere formation medium. Expression levels of stemness markers and CSCrelated markers were higher in tumorsphere-forming cells than in plating-cultured cells. Subsequently, we transplanted the tumorsphere-forming and plating-cultured cells into female nude mice to examine their tumorigenic potential. Tumor volume increased rapidly in mice transplanted with tumorsphere-derived cells compared to plating-cultured cells. We observed a novel sphere-forming condition for REM134 cells and showed that REM134 cell tumorspheres can exhibit improved CSC properties.

Mesenchymal stem cells (MSCs) are useful candidates for tissue engineering and cell therapy. Physiological cell environment not only connects cells to each other, but also connects cells to the extracellular matrix that provide mechanical support, thus exposing the entire cell surface and activating signaling pathways. Hydrogel is a polymeric material that swells in water and maintains a distinct 3-dimensional (3D) network structure by cross linking. In this study, we investigated the optimized cellular function for canine adipose tissue-derived MSCs (cAD-MSCs) using hydrogel. We observed that the expression levels of Ki67 and proliferating cell nuclear antigen, which are involved in cell proliferation and stemness, were increased in transwell-hydrogel (3D-TN) compared to the transwell-normal (TN). Also, transforming growth factor-β1 and SOX9, which are typical bone morphogenesis-inducing factors, were increased in 3D-TN compared to the TN. Collagen type II alpha 1, which is a chondrocyte-specific marker, was increased in 3D-TN compared to the TN. Osteocalcin, which is a osteocyte-specific marker, was increased in 3DTN compared to the TN. Collectively, preconditioning cAD-MSCs via 3D culture systems can enhance inherent secretory properties that may improve the potency and efficacy of MSCs-based therapies for bone regeneration process.

Porcine ear necrosis syndrome is characterized by erosive and ulcerative lesions at the margin or tip of the pinna. Three growing pigs of different ages exhibited retarded growth accompanied by reddening and necrosis of ear prior to death. Gross examination showed reddening, swelling, black discoloration, scaling, and variable-sized yellowish materials and edema in ear cross section. Microscopically, thrombosis, abscess, ulceration, epidermal hyperplasia, and dermal pyogranulomatous inflammation with an intralesional bacterial colony were observed. Staphylococcus hyicus was isolated in all pigs' ears and porcine reproductive and respiratory syndrome virus was detected by PCR and immunohistochemistry.

Porcine parvovirus, Erysipelothrix (E.) rhusiopathiae, and Leptospira (L.) interrogans are considered major etiologic agents of reproductive failure in pigs, causing economic loss in the swine industry. In this study, the safety and immunogenicity of a new octavalent inactivated vaccine were evaluated. The vaccine contained inactivated porcine parvovirus, E. rhusiopathiae, and six L. interrogans serovars (Bratislava, Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae, and Pomona). Safety test results showed no notable side effects or clinical signs after vaccination in mice, guinea pigs, and sows. In addition, we assessed immunogenicity of the vaccine in 25 sows under field conditions. The vaccinated group (n = 20) had a significantly higher antibody level than the non-vaccinated group (n = 5). Moreover, the stillbirth rate decreased in piglets born from vaccinated sows, resulting in an increased fertility rate. The results of this study demonstrate that the new octavalent inactivated vaccine can be applied safely and effectively to improve reproductive performance in sows.