Feline leukemia virus (FeLV) infection is considered a poor prognostic factor for feline lymphoma. This study investigated the prevalence of cats suffering from feline lymphoma with natural infection of the feline leukemia virus, as well as clinical signs, adverse events, and survival time after cyclophosphamide, vincristine and prednisolone (COP) chemotherapy. This retrospective study involved 92 cats diagnosed with mediastinal or mediastinal plus other anatomical sites of lymphoma and treated with COP chemotherapy. FeLV-antigen-positive was observed in all cats. Clinical signs and adverse events were observed after the 1st, 2nd, and 3rd inductions. Clinical signs improved after the 3rd induction of COP chemotherapy. The response rate was 96.74% (81.52% complete response, 15.22% partial response, and 3.26% no response). The overall median survival time was 338 days (range 62–1057 days). The overall response rate and median survival time of cats with feline lymphoma that were FeLV-antigen-positive and treated with COP chemotherapy were higher than from other studies. This study found that cats aged <4 years survived longer than those aged at least 4 years. Anemia (before COP), azotemia (after 2nd induction), and elevated alanine aminotransferase (after 1st induction) were associated with an increased chance of mortality.

The objective of this study was to evaluate the effect of the COP chemotherapeutic protocol on hematological parameters, CD4⁺/CD8⁺ ratio, and the mortality of 18 client-owned FeLV-infected cats with mediastinal lymphoma. The complete blood count, creatinine, alanine aminotransferase, and CD4⁺/CD8⁺ ratio were measured four times before treating with chemotherapy in the 1st, 2nd, 3rd, and 4th weeks. The white blood cell (WBC) counts at the 1st week were significantly different from the 2nd, 3rd, and 4th inductions (p = 0.0075, p = <0.0001, and p = 0.0271, respectively). The neutrophils at the 1st week were significantly different from the 2nd and 3rd inductions (p = 0.0179, and p < 0.0001, respectively). The packed cell volume (PCV) at the 1st week was significantly differed from the 2nd, 3rd, and 4th induction times (p = 0.0029, p = 0.0006, and p = 0.0029, respectively. The mean corpuscular volume (MCV) at the 1st week was significantly different from the 4th week (p = 0.0145). We found that chemotherapy did not cause any significant change in the CD4⁺/CD8⁺ ratio (p-value 0.7407). The Kaplan–Meier curves showed the median survival time (MST) for the cats with a CD4⁺/CD8 ratio of less than 1 after the 1st week of chemotherapy was 134 days. This suggested that COP chemotherapy was a safe treatment for FeLV-infected cats with mediastinal lymphoma.

The most common neoplasms in intact female dogs are CMGTs. BmKn-2, an antimicrobial peptide, is derived from scorpion venom and has published anticancer effects in oral and colon human cancer cell lines. Thus, it is highly likely that BmKn-2 could inhibit CMGT cell lines which has not been previously reported. This study investigated the proliferation and apoptotic properties of BmKn-2 via Bax and Bcl-2 relative gene expression in two CMGT cell lines, metastatic (CHMp-5b) and non-metastatic (CHMp-13a). The results showed that BmKn-2 inhibited proliferation and induced apoptosis in the CMGT cell lines. The cell morphology clearly changed and increased apoptosis in a dose dependent of manner. The half maximum inhibitory concentration (IC₅₀) was 30 µg/mL for CHMp-5b cell line and 54 µg/mL for CHMp-13a cell line. The induction of apoptosis was mediated through Bcl-2 and Bax expression after BmKn-2 treatment. In conclusion, BmKn-2 inhibited proliferation and induced apoptosis in both CHMp-5b and CHMp-13a cell lines via down-regulation of Bcl-2 and up-regulation of Bax relative mRNA expression. Therefore, BmKn-2 could be feasible as candidate treatment for CMGTs.

Chronic rhinitis is a quite common upper respiratory tract (URT) disease in cats. As a result of unclear etiology, frequently, multidrug-resistant bacteria are identified. This study investigated bacterial isolations and an antimicrobial susceptibility test (AST) in chronic rhinitis in cats. The medical records of 395 cats with chronic URT signs were reviewed at the Kasetsart University Veterinary Teaching Hospital (KUVTH) between 2016 and 2021 to survey the underlying causes of URT. Then, apart from rhinitis, other causes were excluded to identify the bacterial species and antimicrobial susceptibility. The results indicated that the most frequent finding was neoplasia, followed by rhinitis and anatomical defects. Furthermore, the only significant association was between the age range and disease group, with gender, FIV, or FeLV infection not being significant. Rhinitis was 4.7 times more likely to occur than neoplasia in younger and young adult cats in the age range < 1–3 years compared to the group > 10 years. The main bacterial species was the Pseudomonas species. Antimicrobials with a susceptibility rate of more than 90% were amikacin, gentamicin, ciprofloxacin, norfloxacin, marbofloxacin, imipenem, and meropenem. In conclusion, rhinitis was the second most common chronic URT disease in cats and was more common in younger and young adult cats. The predominant bacteria with AST in this study reflect the antimicrobial resistance situation. Thus, antimicrobial usage should follow antimicrobial use guidelines first.

Pain assessment in cats is challenging, especially for non-veterinarians. Most validated acute pain scales are designed for clinical use, limiting their applicability for pet owners. This study developed a feline acute pain assessment scale for owners and evaluated its criterion validity, internal consistency reliability, and agreement with three veterinary scales: Glasgow Composite Measure Pain Scale-Feline (CMPS-Feline), Feline Grimace Scale (FGS), and Colorado State University Feline Acute Pain Scale (CSU-FPS). Of 146 enrolled cats, 130 were analyzed after exclusions. The owner-assessed scale showed strong correlation with CMPS-Feline (rho = 0.66) and moderate correlations with FGS (rho = 0.53) and CSU-FPS (rho = 0.57) (all p < 0.001). Agreement was substantial with CMPS-Feline (kappa = 0.74), moderate with FGS (kappa = 0.44), and fair with CSU-FPS (kappa = 0.28) (all p < 0.001). Internal consistency was acceptable (Cronbach’s alpha = 0.76). Receiver operating characteristic analysis demonstrated good discriminatory ability for identifying cats requiring analgesia, with area under the curve values of 0.87 (CMPS-Feline), 0.79 (FGS), and 0.75 (CSU-FPS). A cut-off score of 9 achieved 96% sensitivity and 78% specificity relative to CMPS-Feline. These results support the scale’s potential as a valid tool for pain detection by cat owners in non-clinical settings.

The effect of the semi-quantitative expression of CD20 in the prognosis of feline nasal lymphoma has not been described. This study investigated the prognostic significance of CD20 expression, clinicopathological characterization, and treatment outcomes in cats with nasal lymphoma. Clinical data from cats diagnosed with nasal lymphoma were retrospectively collected, including signalment, clinical signs, clinicopathological variables, treatment outcomes, and survival times. Using ImageJ software, CD20 expression was semi-quantitatively measured based on the proportion of CD20-positive areas. Correlations between laboratory findings, immunohistochemical expressions, and survival outcomes were investigated. All cats included in the study exhibited the B-cell immunophenotype. During treatment, a reduction in PCV was noted in the cats at the second and sixth weeks (p = 0.01 and p = 0.01, respectively). The cats with low CD20 expression exhibited a significantly shorter MST (91 days; 95% CI, 41–141) than those with high CD20 expression (MST, 214 days; 95% CI, 76–351) (p = 0.01). Stage T1 cats displayed a higher MST (143 days; 95% CI, 144–172) than those in other stages > T1 (120 days, 95% CI, 71–169 days) (p = 0.04). Anemia, a common adverse effect in feline nasal lymphoma, did not impact MST. T1 clinical staging and high CD20 expression showed a trend for better MST.