Background and Aim: Chronic wounds are a clinical problem and require intensive standard wound care. However, this is sometimes insufficient to promote healing. Photobiomodulation therapy (PBMT) can be used as an adjunctive therapy to improve wound healing. Various PBMT devices with different properties and parameter settings as well as different animal species can influence a variety of clinical outcomes. This study aims to assess the use of 830 nm PBMT or simultaneous superpulsed and multiple wavelengths (SPMW; 660, 875, and 905 nm) PBMT on chronic wounds in client-owned dogs. Materials and Methods: This study included 21 client-owned dogs with chronic wounds allocated into three groups: (1) Control group (C) treated with irrigated saline and without PBMT (n=7); (2) L1 group treated with irrigated saline together with the radiation of 830 nm PBMT (n=7); and (3) L2 group treated with irrigated saline together with the radiation of simultaneous SPMW-PBMT (n=7). Wound healing was assessed on the basis of wound size reduction as a percentage of wound area every 2nd day for 15 days using image analysis software (ImageJ software®, National Institutes of Health, Rockville, Maryland, USA). Results: A significant difference in the percentage of wound area reduction was noted between the C and PBMT groups (L1 and L2; p<0.05). The average percentages of wound area reduction at the end of the study (15 days) were 42.39±20.58, 56.98±24.82, and 61.81±27.18 in the C, L1, and L2 groups, respectively. A steady decrease in wound size was noted in both PBMT and non-PBMT groups, and coefficients were 7.77, 8.95, and 10.01 in the C, L1, and L2 groups, respectively. The percentage of wound area reduction was found to be significantly different between the PBMT and non-BPMT groups on day 7 (p<0.05). Conclusion: Based on the results of the current study, using either 830 nm PBMT or simultaneous SPMW-PBMT can accelerate the chronic wound healing process in dogs with a significant reduction in wound area. Therefore, it can be used as an adjunctive therapy to improve wound healing in dogs with reduced treatment duration.

Background and Aim: Recent studies have shown that low-intensity laser therapy (LILT) enhances chronic wound healing, reduces pain, reduces inflammation, and improves post-operative rehabilitation. However, clinical outcomes in the veterinary use of LILT vary between different experimental studies. This is explained by improper laser parameter settings and limits of its penetration depth. This study aimed to investigate the penetration depth of 830 nm LILT on living dog tissue in different operating modes. This entailed continuous wave (CW) versus pulse wave (PW) and with contact versus non-contact techniques of the laser probe at different tissue-laser probe distances. The results can be applied for use in clinical practice. Materials and Methods: Twenty-four dogs that had undergone abdominal surgery were included in this study. The laser parameters were set at 200 mW, fluence of 4 J/cm2 and the laser power output denoted as mean output power (MOP) was measured by a power meter. Results: The MOP of the 830 nm CW laser was significantly higher than the PW laser (p<0.05). The MOP of the contact technique was significantly greater than that of the non-contact technique in both CW and PW modes (p<0.05). The MOP through the skin tissue was between 16.09 and 18.60 mW (8.05-9.30%) for the contact technique and 8.73 and 19.36 mW (4.37-9.68%) for the non-contact technique. In the muscle-skin layer, the MOP was between 0.50 and 1.56 mW (0.25-0.78%) and the MOP was not detected using the non-contact technique with a 5 cm tissue-laser probe distance. Conclusion: Our study indicates that 830 nm LILT (with laser parameter setting at 200 mW, fluence of 4 J/cm2 for both contact and non-contact techniques, and tissue-laser probe distance up to 5 cm) was appropriate for treatments within 14 mm of depth. However, the use of 830 nm LILT for an application in which the target tissue is deeper than 14 mm may limit its positive effect.

Background and Aim: Low-level laser therapy (LLLT) has shown benefits as an alternative treatment of feline chronic gingivostomatitis by reducing pain and inflammation within the oral cavity. Extraoral application technique in cats provides more comfort compared to intraoral application. However, the efficacy of LLLT through buccal tissue is still controversial. This study aimed to investigate the penetration efficacy of LLLT using 830 nm continuous waves with various settings and different application techniques. Materials and Methods: Twenty-four healthy cats were included in this study. The wavelength of LLLT was 830 nm with an output power of 200 mW through extraoral application, using fluences of 2 and 6 J/cm2 in continuous-wave mode. This study compared different distances (contact and non-contact) and three different transmission media (absent media, alcohol, and normal saline solution). Measurement of the laser power within the oral cavity is represented as the mean output power (MOP). Results: Penetration efficacy was detectable for all fluences, distances, and transmission media, with an average buccal thickness of 2.68 mm. MOP did not differ between fluences of 2 and 6 J/cm2 (p = 0.19). In the absence of media, MOP was significantly higher compared with alcohol (p < 0.05) but was not significantly different from normal saline solution (p = 0.26). Conclusion: Extraoral application of LLLT demonstrated penetration efficacy through the buccal tissue with both contact and non-contact skin (<10 mm). This is a potential alternative treatment for oral diseases in clinical practice. However, there is a need for further study on the efficacy of treatment in clinical practice. Keywords: chronic gingivitis, near-infrared light, penetration, photobiomodulation, transmission.

Femoral head and neck excision (FHNE) remains a common orthopedic surgical procedure in many countries. However, data on postoperative outcomes regarding changes in hindlimb function are limited. This study aimed to evaluate hindlimb function after FHNE in dogs of different weights. Twenty-seven dogs that underwent FHNE were block-randomly assigned to two groups based on weight (≤20 kg and >20 kg). Hindlimb function was evaluated using force plate gait analysis to measure peak vertical force (PVF), alongside other orthopedic evaluations and a composite orthopedic assessment score at 1, 2, 3, 4, 5, 6, 9, and 12 months after surgery. Kaplan–Meier survival analysis and the log-rank test were used for statistical comparisons. The findings demonstrated no significant difference in PVF between the operated and non-operated limbs in either weight groups (≤20 kg and >20 kg) at four and three months postoperatively (median functional recovery time) (p = 0.33), nor were there significant differences in lameness scores at trot between weight groups five and three months after FHNE (p = 0.64). These results indicate that FHNE provides satisfactory functional outcomes and can be considered a suitable orthopedic intervention for medium- to large-breed dogs.

This study investigates the susceptibility of common pathogens to totarol and assesses its clinical effectiveness in promoting wound healing in client-owned dogs with open wounds. Twenty-three client-owned dogs with open wounds were divided into two groups: (1) the treatment group (T-group) and (2) the control group (C-group). Clinical samples were collected from the wounds for the bacterial identification and determination of the minimum inhibitory concentrations (MICs) of totarol. In the T-group, wounds were treated with standard wound care together with the application at a dosage of 0.3 mL (two sprays) of commercial totarol product per 25 cm² of the wound area. The C-group received only standard wound care. This in vitro study found that totarol exhibited antimicrobial activity against both standard pathogens and clinical wound pathogens. The MIC values of totarol dissolved in absolute ethyl alcohol were 4 µg/mL for Gram-positive pathogens and ranged from 256 to 512 µg/mL for Gram-negative pathogens. However, the MIC values of the commercial totarol product ranged from 512 to 1024 for both Gram-positive and Gram-negative pathogens. Clinically, the use of a commercial totarol product as an adjunctive therapy significantly improved wound healing, as indicated by a greater percentage of wound area reduction (p < 0.05). From day 2 to day 7 of the treatment, the percentage of wound area reduction differed significantly between the T-group and the C-group. At the end of the study, the average percentage of wound area reduction was 69.18% ± 18.12 and 41.50% ± 20.23 in the T-group and C-group, respectively. The finding of this study illustrates the antimicrobial properties of totarol and its product against prevalent wound pathogens. These results suggest the potential of totarol as an adjunctive option for canine wound care.

Background and Aim: Antibiotic resistance poses a growing threat to wound management in veterinary medicine. Blue light phototherapy has emerged as a non-antibiotic bactericidal alternative with additional benefits for wound healing. However, its effectiveness in clinical veterinary contexts remains inadequately explored. This study evaluated the bactericidal efficacy of 465-nm blue light against standard pathogens and bacteria isolated from infected canine wounds, aiming to determine optimal energy doses for clinical use. Materials and Methods: Three standard bacterial strains – Staphylococcus aureus (American Type Culture Collection [ATCC] 25923), Pseudomonas aeruginosa (ATCC 27853), and Escherichia coli (ATCC 25922) – along with five clinical isolates from canine wounds, were exposed to 465-nm blue light at energy doses of 28, 56, and 112 J/cm2 (15, 30, and 60 min, respectively). Colony-forming units (CFUs) were quantified post-irradiation and compared to non-irradiated controls. Statistical significance was assessed using appropriate parametric and non-parametric tests. Results: P. aeruginosa (ATCC 27853) exhibited significant, dose-dependent inhibition at all energy doses, resulting in reductions of 36.3%, 60.5%, and 82.8%. Clinical P. aeruginosa isolates demonstrated 21.1% and 78.8% inhibition at 56 and 112 J/cm2, respectively (p < 0.05). E. coli (ATCC 25922) was significantly inhibited only at 112 J/cm2 (46.4% reduction, p = 0.045). No significant reductions were observed for S. aureus, Acinetobacter baumannii, Staphylococcus haemolyticus, clinical E. coli, or Enterococcus faecalis at any dose. Conclusion: Blue light at 465-nm exhibits selective bactericidal activity, effectively inhibiting P. aeruginosa and E. coli (ATCC), with efficacy dependent on bacterial species and applied energy dose. Its limited effect on other pathogens underscores the importance of species-specific treatment planning. Higher energy doses (112 J/cm2) may be required in unknown or mixed infections. Further investigation is recommended to refine device specifications and assess clinical utility in veterinary settings. Keywords: antimicrobial resistance, blue light therapy, Escherichia coli, photoinactivation, Pseudomonas aeruginosa, veterinary phototherapy.