BPH is the most prevalent prostatic condition in aging dogs. Nevertheless, clinical diagnosis and management remain inconsistent. This study employed in-solution digestion coupled with nano-liquid chromatography tandem mass spectrometry to assess serum proteome profiling of dogs with BPH and those dogs after castration. Male dogs were divided into two groups; control and BPH groups. In the BPH group, each dog was evaluated at two time points: Day 0 (BF subgroup) and Day 30 after castration (AT subgroup). In the BF subgroup, three proteins were significantly upregulated and associated with dihydrotestosterone: solute carrier family 5 member 5, tyrosine-protein kinase, and FRAT regulator of WNT signaling pathway 1. Additionally, the overexpression of polymeric immunoglobulin receptors in the BF subgroup hints at its potential as a novel protein linked to the BPH development process. Conversely, alpha-1-B glycoprotein (A1BG) displayed significant downregulation in the BF subgroup, suggesting A1BG’s potential as a predictive protein for canine BPH. Finasteride was associated with increased proteins in the AT subgroup, including apolipoprotein C-I, apolipoprotein E, apolipoprotein A-II, TAO kinase 1, DnaJ homolog subfamily C member 16, PH domain and leucine-rich repeat protein phosphatase 1, neuregulin 1, and pseudopodium enriched atypical kinase 1. In conclusion, this pilot study highlighted alterations in various serum proteins in canine BPH, reflecting different pathological changes occurring in this condition. These proteins could be a source of potential non-invasive biomarkers for diagnosing this disease.

Phenylbutazone (PBZ) is a widely used nonsteroidal anti-inflammatory drug for horses. However, because of its gastrointestinal side effects, its administration requires careful attention in veterinary practice. Malondialdehyde (MDA) is a serum biomarker associated with increased damage to the equine gastrointestinal system. This study investigated the hematological effects and alterations in the gastrointestinal tract and assessed serum MDA concentrations following repeated oral PBZ administration at clinical doses. Fourteen horses were randomly divided into control and treatment groups. All horses in the treatment group were administered 4.4 milligrams per kilogram of body weight of PBZ syrup orally twice a day for 7 days, whereas the control group received syrup as a placebo. The development of gastrointestinal side effects was investigated using gastroscopy, abdominal ultrasound, and fecal pH; serum MDA concentrations were assessed using a commercially available enzyme-linked immunosorbent assay kit. Data were compared between PBZ-treated and control horses before and after the treatment period. The treatment group exhibited decreased albumin and total protein concentrations. Moreover, this group exhibited a higher thickness of the right dorsal colon wall (p = 0.03) and had higher scores for squamous gastric ulcers (p = 0.01). Fecal pH was lower in the treatment group than in the control group after PBZ administration (p < 0.01). Although MDA concentrations were higher in the treatment group after PBZ administration, they did not differ significantly from those of the control group. This study highlighted the changes in hematological and gastrointestinal lesions resulting from PBZ administration in horses at clinical doses, even without clinical signs. However, MDA may not be an optimal biomarker for the early detection of gastrointestinal damage due to PBZ treatment in horses.

Background and Aim: Benign prostatic hyperplasia (BPH) is a prevalent disorder in aging male dogs, characterized by prostate enlargement secondary to hormonal dysregulation and chronic inflammation. Identifying non-invasive biomarkers is crucial for improving diagnosis and monitoring therapeutic interventions. This study aimed to evaluate serum alpha-1B glycoprotein (A1BG) and C-reactive protein (CRP) concentrations in dogs with BPH before and after castration, to assess their diagnostic and prognostic utility. Materials and Methods: A total of 20 male dogs were assigned to two groups: healthy controls (n = 10) and BPH-affected dogs (n = 10). Blood samples were collected from controls and the BPH group at diagnosis and 1 month post-castration. Serum A1BG and CRP concentrations were measured using enzyme-linked immunosorbent assay and fluorescence immunoassay, respectively. Prostatic volume (PV) was evaluated ultrasonographically. Results: Dogs with BPH demonstrated significantly lower serum A1BG concentrations before castration compared to healthy controls (p < 0.01) and post-castration (p < 0.01). Post-castration A1BG levels were comparable to controls, suggesting biochemical normalization. Serum CRP concentrations remained within the normal range (<30 mg/L) across all groups and showed no significant differences. A significant negative correlation was observed between age and A1BG concentration in the pre-castration BPH group (r = −0.74, p = 0.02). Castration resulted in a marked reduction in PV, consistent with therapeutic response. Conclusion: Serum A1BG demonstrated potential as a sensitive biomarker for the diagnosis and therapeutic monitoring of canine BPH, in contrast to CRP, which exhibited limited diagnostic value. Normalization of A1BG levels post-castration supports its role in reflecting disease resolution. Integrating A1BG assessment into veterinary diagnostic workflows could enhance early detection, monitoring, and management strategies for BPH, offering a non-invasive and clinically informative approach. Further longitudinal studies with larger cohorts are warranted to validate these findings and explore long-term biomarker dynamics. Keywords: alpha-1B glycoprotein, benign prostatic hyperplasia, canine biomarkers, castration, C-reactive protein.

Equine melanocytic neoplasms (EMN) are aggressive tumours characterised by high metastatic potential and limited therapeutic options available. However, the molecular mechanisms underlying their progression remain poorly understood. This study therefore presents the integrative phosphoproteomic analysis of EMN tissue, with the aim of elucidating stage‐specific alterations in signalling pathways and metabolism. Nineteen tissue samples from grey horses were categorised as normal‐stage ( n = 6), early‐stage EMN ( n = 7), and severe‐stage EMN ( n = 6) and subjected to in‐depth analysis using liquid chromatography–tandem mass spectrometry (LC–MS/MS). A total of 2035 phosphoproteins were identified, of which 219 were differentially expressed across the disease stages. Interestingly, early‐stage EMN showed dysregulation of inositol phosphate metabolism and activation of the PI3K‐Akt pathway which involved INPP5F and PKN2. In severe‐stage EMN, upregulation of SYNJ1, STRN4 and VIM indicated enhanced membrane trafficking, cytoskeletal remodelling, and MAPK signalling. Additionally, ASPM and GNAO1 upregulation reflected heightened proliferation and altered Rap1 signalling, while UBR5 dysregulation suggested aberrant protein homeostasis. Metabolic reprogramming was also noticed, with elevated TKT and GAPDH expression supporting glycolysis and NADPH production. Observably, the severe‐stage EMN exhibited a higher expression of Dickkopf‐3 (DKK3) which suggests a role in aberrant Wnt/β‐catenin activation and tumour progression. These findings reveal stage‐specific molecular mechanisms in EMN pathogenesis and highlight potential biomarkers and therapeutic targets for equine melanoma.

Malignant mesothelioma is an uncommon tumor that has a challenging diagnosis and a tendency for late diagnosis. A 7-year-old intact male dog presented with respiratory distress. Thoracic radiography revealed pleural effusion and bone reactions at multiple ribs. A computerized tomography scan with rib biopsy was suggested as a diagnosis plan. Unfortunately, the dog died. Gross pathological findings demonstrated multifocal to coalescing, pinkish-white firm masses scattered over the parietal pleural surface, extended to the serosa of the diaphragm and the pericardium, making them adhere to each other and causing the coalescence of a white irregular mass at the diaphragm. Multiple white to pink nodules were also noted at the intercostal muscle, mediastinum, and peritoneum. The histopathologic findings indicated a diffuse nodular structure of neoplasm in the pleura, mediastinum, pericardium, peritoneum, and lungs. The nodules were mainly composed of neoplastic epithelioid cells mixed with a minor component of atypical spindle-shaped cells. A biphasic malignant mesothelioma was considered according to gross appearance, location of lesions, and histopathological findings. The histopathological characteristics of this tumor were confirmed by immunohistochemical staining of vimentin, cytokeratin, and desmin. This report describes the pathomorphological, histopathological, and immunohistochemical features of tri-cavitary biphasic malignant mesothelioma in a dog.