Sakchai Ruenphet

Feline hemotropic mycoplasmosis presents a diagnostic challenge in clinical practice because of the variable pathogenicity of Mycoplasma species and the limited sensitivity of conventional blood smear examination, highlighting the need for rapid and accurate point-of-care molecular diagnosis. This study aimed to evaluate the diagnostic performance of the Pluslife^® Feline Hemotropic Mycoplasma (FHM) nucleic acid test card and to determine the detection frequency of the pathogen among clinically ill cats presented to a veterinary teaching hospital in Bangkok, Thailand. Whole blood samples were collected from 114 clinically ill cats presented to Kasetsart University Veterinary Teaching Hospital between September 2025 and May 2026. The nucleic acid test card assay was evaluated against conventional PCR targeting the 16S rRNA gene as the reference method. PCR identified ‘Candidatus Mycoplasma haemominutum’ (CMhm) as the predominant Mycoplasma species (45.61%), followed by Mycoplasma haemofelis (Mhf; 5.26%) and ‘Candidatus Mycoplasma turicensis’ (CMt; 0.88%). Compared with conventional PCR, the nucleic acid test card assay demonstrated a sensitivity of 93.22%, specificity of 96.36%, overall accuracy of 94.74%, and precision of 96.49%, with results available within 30 min. Sequence analysis of discordant samples confirmed CMhm in four false-negative specimens, suggesting that low bacterial burdens or other assay-related factors may have contributed to the discordant results. Overall, the Pluslife^® FHM assay demonstrated high diagnostic performance and may provide a practical rapid molecular point-of-care tool to support timely diagnosis and clinical decision-making in cats with suspected hemotropic mycoplasmosis.

Background and Aim: Hypoluteodism is an important cause of non-infectious pregnancy loss in bitches and is characterized by inadequate progesterone (P4) production by the corpus luteum. Evidence regarding breed-specific patterns of luteal insufficiency and the clinical utility of medroxyprogesterone acetate (MPA) with timed-withdrawal remains limited. This study aimed to identify the temporal pattern of luteal insufficiency in predisposed dog breeds and to evaluate the efficacy and safety of an MPA protocol combined with standardized late-gestation withdrawal. Materials and Methods: Clinical records from 29 pregnancies in 25 bitches diagnosed with hypoluteodism were retrospectively reviewed. The cohort consisted predominantly of Shetland Sheepdogs (21), together with Miniature American Shepherds (2) and Pomeranians (2). Serial serum P4 monitoring commenced during the fourth week of gestation. Hypoluteodism was diagnosed when P4 concentrations decreased below 10 ng/mL or declined by >5 ng/mL within 48–72 h. A low-dose MPA regimen (0.1 mg/kg, orally, once daily) was administered, and treatment was discontinued 24–48 h before elective cesarean section. Pregnancy outcomes and maternal and neonatal safety parameters were evaluated. Results: A distinct mid-gestational critical window was identified, with 79.3% of cases exhibiting P4 decline during weeks 5–6 of gestation. Pregnancy was successfully maintained to term in 86.2% (25/29) of pregnancies. Reproductive failure occurred in four pregnancies (13.8%), including three abortions and one case of fetal mummification. Mean litter size was approximately 4.4 puppies, yielding 110 live-born neonates, of which 94.5% survived to weaning. Female puppies showed no evidence of virilization, and no maternal complications, including diabetes mellitus, mammary hyperplasia, mammary tumors, or agalactia, were observed. Timed-withdrawal of MPA before delivery prevented premature labor and fetal compromise. Conclusion: Predisposed breeds, particularly Shetland Sheepdogs, exhibit a predictable period of luteal vulnerability during weeks 5–6 of gestation. Early P4 surveillance beginning at day 28–30 post-ovulation, combined with low-dose MPA therapy and withdrawal 24–48 h before elective delivery, represents an effective clinical strategy for reducing pregnancy loss while facilitating planned cesarean section. Keywords: canine pregnancy, cesarean section, hypoluteodism, luteal insufficiency, medroxyprogesterone acetate, progesterone monitoring, Shetland Sheepdog, synthetic progestins.

Background and Aim: Objective assessment of the postoperative acute phase response following major orthopedic surgery, such as tibial plateau leveling osteotomy (TPLO), is essential for distinguishing uncomplicated recovery from infectious complications. Serum C-reactive protein (CRP) levels typically return to baseline by 14 days postoperatively, whereas total white blood cell (WBC) counts may remain nonspecifically elevated due to physiological stress. This study aimed to prospectively characterize and directly compare the postoperative kinetics of point-of-care CRP and total WBC counts in dogs undergoing TPLO. Materials and Methods: Thirteen client-owned dogs undergoing standardized TPLO (classified as Level 4 severity) were prospectively enrolled. Venous blood samples were collected preoperatively (Day 0) and on postoperative days 1, 3, 5, 7, 10, and 14. Serum CRP concentrations were measured using a validated point-of-care immunofluorescence assay (SmartDiag®), and total WBC counts were determined concurrently using an automated hematology analyzer. Temporal changes in both biomarkers were analyzed using a repeated-measures one-way analysis of variance with Dunnett’s post hoc test. Results: Both biomarkers increased significantly from baseline and peaked on postoperative day 1 (p < 0.05). However, their subsequent kinetics diverged markedly. Mean serum CRP concentrations showed a rapid and progressive decline, approaching preoperative baseline levels by postoperative day 7 and remaining stable thereafter. In contrast, mean total WBC counts remained significantly elevated above baseline throughout the entire 14-day monitoring period without returning to preoperative values. A moderate positive correlation between CRP and WBC was observed only on day 1 (ρ = 0.58, p < 0.05); no significant correlations were found from day 7 onward. Conclusion: The postoperative kinetics of point-of-care CRP and total WBC counts are fundamentally different after TPLO. CRP provides a reliable, dynamic profile that accurately reflects the resolution of acute inflammation in uncomplicated cases, whereas total WBC count is an unreliable biomarker due to persistent non-specific elevation from surgical stress. These findings support serial point-of-care CRP measurement as a superior objective tool for monitoring postoperative recovery and early detection of complications in dogs undergoing TPLO. Keywords: C-reactive protein, tibial plateau leveling osteotomy, point-of-care CRP analyzer, white blood cell count, acute phase response, postoperative monitoring.

African Swine Fever (ASF) control is severely hampered by the reliance on slow, laboratory-bound diagnostics. While rapid, field-deployable lateral flow assays (LFAs) are urgently needed, the comparative performance of key single-antigen targets remains poorly characterized. This study aimed to develop and systematically evaluate the diagnostic performance of three in-house single-antigen LFAs targeting ASF virus P30, P54, and P72, using swine field samples from Thailand, including a panel of 143 quantitative polymerase chain reaction-negative swine serum samples. The performance of each LFA was compared against a commercial multi-antigen (P32/P62/P72) indirect ELISA, which served as the reference standard, classifying 64 samples as positive and 79 as negative. The P72-based LFA demonstrated perfect diagnostic performance (100% sensitivity, 100% specificity) and perfect agreement (κ = 1.0) with the enzyme-linked immunosorbent assay (ELISA). Similarly, the P30 LFA demonstrated high performance (100% sensitivity, 98.7% specificity) with ‘Almost Perfect’ agreement (κ = 0.9859). In contrast, the P54 LFA was unsuitable, achieving 100% sensitivity but unacceptably low specificity (88.6%) due to a high rate of false positives. Overall, the single-antigen P72 and P30 LFAs demonstrated excellent concordance with the multi-antigen ELISA, supporting their reliable for detecting antibodies against ASFV. Although these assays do not replace molecular methods for acute infection detection, they represent valuable complementary tools for serosurveillance.

Surgical intervention is essential for many orthopedic conditions in dogs, which are a common cause of pain and debilitation

African Swine Fever (ASF) control is severely limited by a diagnostic gap, as laboratory-based quantitative polymerase chain reaction (qPCR) is highly sensitive but slow, whereas field-deployable immunochromatographic assays (ICAs) are rapid but unreliable. To address this limitation, this study evaluated a novel, rapid isothermal assay, RNase hybridization-assisted amplification (RHAM), as a high-sensitivity, point-of-need diagnostic solution. This study compared the performance of RHAM and a conventional p72-based ICA against the qPCR reference standard using 106 diverse clinical field samples, including oral swabs, blood, serum, and organs, collected from suspected ASF cases in Thailand. The ICA exhibited markedly low diagnostic performance, achieving only 56.76% sensitivity and showing moderate agreement (κ = 0.421) with qPCR, highlighting the need for a more reliable alternative. In contrast, the RHAM assay achieved 94.59% sensitivity and 96.88% specificity, providing results rapidly within 35 min. This statistically superior performance (McNemar’s test, p < 0.0001) demonstrated almost perfect agreement (κ = 0.891) with the qPCR reference standard, missing only four samples with very high Ct values (>30). In conclusion, RHAM is a powerful, accurate, and field-deployable diagnostic tool that effectively bridges the diagnostic gap, offering qPCR-like sensitivity for the rapid containment of ASF outbreaks.

Feline leukemia virus (FeLV) and Feline immunodeficiency virus (FIV) are globally prevalent retroviral pathogens that pose significant health risks to domestic cats. This study aimed to compare the diagnostic performance of two point-of-care—the immunochromatographic assay (ICA) and the RNase hybridization-assisted amplification (RHAM) test kit—against reverse transcription quantitative polymerase chain reaction (RT-qPCR), the current gold standard for FeLV and FIV detection. For FeLV detection, ICA demonstrated a sensitivity of 86.89%, specificity of 96.55%, accuracy of 90.00%, and precision of 98.15%, while for FIV detection, the assay showed a sensitivity of 75.86%, specificity of 88.52%, accuracy of 84.44%, and precision of 75.86%. In contrast, the RHAM test exhibited superior performance, with FeLV detection sensitivity of 93.44%, specificity of 98.28%, accuracy of 94.44%, and precision of 98.28%. For FIV detection, RHAM demonstrated a sensitivity of 75.86%, specificity of 100%, accuracy of 92.22%, and precision of 100%. Additionally, the RHAM assay significantly reduced detection time compared to RT-qPCR, enabling expedited clinical decision-making, alleviating laboratory workload, and lowering diagnostic costs. These benefits are particularly relevant in veterinary settings with limited access to PCR-based diagnostics, where the RHAM assay represents a rapid, reliable, and resource-efficient alternative for FeLV and FIV detection.

Background and Aim: Canine vector-borne pathogens, particularly blood parasites, pose significant health threats to domestic dogs, ranging from subclinical infections to severe systemic diseases. In Thailand, microscopic examination remains the standard diagnostic method, despite its limitations. This study aimed to (i) determine the prevalence of major canine vector-borne pathogens in Bangkok, Thailand during the 2024 rainy season and (ii) evaluate the diagnostic performance of microscopy and a novel RNase hybridization-assisted amplification (RHAM) test kit in detecting canine Ehrlichiosis, compared to the quantitative polymerase chain reaction (qPCR) gold standard. Materials and Methods: A total of 134 whole blood samples were collected from clinically suspected dogs. Microscopy was performed on Giemsa-stained blood smears, and the RHAM test kit was employed for nucleic acid detection. qPCR served as the reference method. Sensitivity, specificity, accuracy, and precision of each diagnostic method were calculated relative to qPCR results. Results: Microscopic examination revealed the following infection prevalences: Ehrlichia spp. (26.12%), Babesia spp. (4.48%), Hepatozoon canis (6.72%), Anaplasma spp. (0.75%), Dirofilaria immitis (3.73%), and Brugia spp. (3.73%). Compared with qPCR, microscopy demonstrated a sensitivity of 51.47%, specificity of 87.88%, accuracy of 69.40%, and precision of 81.39% for Ehrlichiosis detection. In contrast, the RHAM test kit achieved markedly higher diagnostic metrics: Sensitivity (91.18%), specificity (98.48%), accuracy (94.78%), and precision (98.41%). Notably, the RHAM kit provided rapid, user-friendly detection, approximating qPCR diagnostic performance, although its sensitivity slightly declined in samples with very low pathogen titers. Conclusion: This study highlights the continued high prevalence of Ehrlichiosis among dogs in Bangkok during the rainy season. Although microscopy remains practical, its diagnostic limitations are significant. The RHAM test kit demonstrated excellent sensitivity and specificity, offering a rapid and accurate alternative for Ehrlichiosis detection, particularly suitable for resource-limited settings lacking qPCR capabilities. Adoption of the RHAM assay could improve early diagnosis and management of canine Ehrlichiosis at grassroots veterinary facilities. Keywords: canine blood parasites, ehrlichiosis, microscopy, quantitative polymerase chain reaction, RNase hybridization-assisted amplification test kit.

Standard serological tests post-vaccination, such as enzyme-linked immunosorbent assay (ELISA), complement fixation, and virus neutralization, are crucial for monitoring African horse sickness (AHS). However, the availability of commercial test kits such as blocking ELISA varies by regions; while they are commonly used in Africa and Europe, their limited availability and high cost in Thailand present significant challenges. Therefore, this study aimed to evaluate an alternative approach using an in-house indirect ELISA based on cell-based monovalent and polyvalent strains of live attenuated AHS virus. This method addresses the cost and accessibility issues faced in Thailand. This study demonstrated promising results: the in-house indirect ELISA showed analytical sensitivity and specificity values of 88.30% and 67.02% for monovalent strains and 87.23% and 84.04% for polyvalent strains, respectively, compared to the blocking ELISA. These findings underscore the efficacy of the in-house ELISA as a viable serodiagnostic tool for AHS. Furthermore, the polyvalent antigen-based in-house indirect ELISA proved to be a reliable alternative for AHS monitoring, particularly in vaccinated horses, offering enhanced specificity. Additionally, this method is simpler, cheaper, faster, and more convenient than blocking ELISA and serum neutralization tests, making it a practical choice for routine AHS surveillance.

Background and Aim: Potassium peroxymonosulfate (PPMS) is a broad-spectrum disinfectant that oxidizes viral protein capsids. The effectiveness of PPMS in killing viruses depends on several factors, including its concentration, contact time, and present of organic materials. This study evaluated the efficacy of PPMS in an aqueous phase. It also applied PPMS to artificially avian influenza virus (AIV)-contaminated carrier surfaces and clothes and compared its effectiveness with that of sodium dichloroisocyanurate (NaDCC) and quaternary ammonium compounds (QAC). Materials and Methods: Four PPMS concentrations (1×, 0.5×, 0.25×, and 0.125×), were evaluated for their virucidal efficacy against Newcastle disease virus (NDV) and AIV in an aqueous phase. The evaluation included testing in the absence and presence of organic materials under different exposure times, such as 5 s, 30 s, 1 min, 3 min, 5 min, 10 min, and 15 min. AIV inactivation was assessed on contaminated carrier surfaces, such as stainless steel, rubber, plastic, and artificially contaminated clothes. Results: In aqueous phase, concentrations of 1×, 0.5×, 0.25×, and 0.125× inactivated NDV in the absence of organic materials within 5 s, 5 s, 5 min, and 15 min at concentrations of 1×, 0.5×, 0.25×, and 0.125×, respectively. In the presence of organic material contamination, NDV could be inactivated within 30 s for 1×, 1 min for 0.5×, and 10 min for 0.25×; however, 0.125× PPMS did not achieve inactivation within 15 min. PPMS concentrations of 1×, 0.5×, 0.25×, and 0.125× inactivated AIV within 5 s, 5 s, 5 s, and 30 s, respectively, in both the absence and presence of organic materials. PPMS at a concentration of 1× could inactivate AIV on all carriers within 30 s. PPMS at 0.5× and 0.25× concentrations could inactivate AIV within 30 s on rubber and plastic; inactivation occurred within 1 min on stainless steel. However, 0.125× PPMS and 1× QAC could not achieve inactivation within 3 min on all carriers. Finally, PPMS concentrations of 1×, 0.5×, 0.25×, and 0.125× inactivated AIV on rayon sheets within 5 s, 30 s, 5 min, and 15 min, respectively. However, the recommended NaDCC concentration achieved inactivation within 10 min, whereas QAC did not achieve inactivation within 15 min. Conclusion: PPMS can inactivate enveloped viruses such as NDV and AIV. Furthermore, PPMS is superior to NaDCC and QAC for inactivating viruses on various carrier surfaces and artificially contaminated clothes. However, the virucidal efficacy of PPMS depends on the optimal concentration, organic material conditions, and exposure/contact timing. Therefore, PPMS is a promising alternative disinfectant crucial for enhancing biosecurity and controlling viruses that contaminate animal farms, slaughterhouses, and hospitals. Keywords: avian influenza virus, disinfectant, Newcastle disease virus, potassium peroxymonosulfate, virucidal.