Encephalitozoon cuniculi can cause serious disease and subclinical infection in rabbits and requires active surveillance to control the infection. This study investigated the association between anti-Encephalitozoon cuniculi antibody status and various health parameters in pet rabbits. A total of 90 rabbits were divided into healthy (N = 30), subclinical (N = 30), and clinical (N = 30) groups based on their anti-Encephalitozoon cuniculi antibody status and clinical presentations. The mean ages of the control (37 ± 40 months) and subclinical groups (38 ± 34 months) were notably lower compared to that of the clinical group (63 ± 38 months, p < 0.01). Serum titers for anti-Encephalitozoon cuniculi antibodies were significantly elevated in rabbits with subclinical and clinical infections compared to those of healthy rabbits (p < 0.05). Neurological signs were predominant in rabbits with active E. cuniculi infection (80.0%), with additional pathological features including urinary dysfunction (10.0%) and cataracts (10.0%). The source of rabbits was not associated with E. cuniculi infection (p = 0.159). Anemia was significantly linked to E. cuniculi infection (p = 0.026); however, no significant associations were found with leukocytosis, thrombocytopenia, or serum biochemistry parameters. Mature adult rabbits were more likely to be infected with E. cuniculi. Recognizing anemia and neurological signs facilitates in early diagnosis of E. cuniculi infection.

Background and Aim: The sun conure (Aratinga solstitialis), a bird belonging to the Psittaciformes family, is a popular pet because of its bright color and beautiful appearance. The sun conure is a monomorphic bird with similar appearances between males and females, making sex identification difficult by observing the external morphology. Therefore, molecular techniques are utilized. Loop-mediated isothermal amplification (LAMP) is a molecular technique that is often applied for sex identification in birds and is a quick and simple method that can be used in the field. This study used the LAMP technique to improve sex identification in sun conures by observing the color change of hydroxy naphthol blue. Materials and Methods: Two primer sets, SunSpin-W and SunSpin-Z, were designed for sex identification in sun conures using the LAMP technique specific to the spindlin gene. The developed LAMP reaction was tested for optimal conditions, sensitivity, and specificity compared with the polymerase chain reaction (PCR) technique. Results: The SunSpin-W primer set amplified only female birds, whereas the SunSpin-Z primer set amplified DNA from both male and female birds. The primer sets were optimized at 62°C for 45 min. A positive result was visible to the naked eye from the color change of the reaction. In the LAMP assay, the lowest detectable concentration was 10 pg/μL and in the PCR assay, it was 1 ng/μL, while a 100% accuracy rate in sex identification was observed when comparing the LAMP assay results with the PCR assay. Conclusion: This study successfully developed a LAMP technique for sex identification of sun conure, which took 45 min to complete and can be expanded for use in the field. Keywords: loop-mediated isothermal amplification, sex identification, spindlin gene, sun conure.

Background and Aim: Duck circovirus (DuCV) is an immunosuppressive pathogen linked to poor growth, feather abnormalities, and increased susceptibility to co-infections, leading to significant economic losses in duck production. Rapid and large-scale serological screening tools are essential for epidemiological surveillance and biosecurity. This study aimed to develop and validate an indirect enzyme-linked immunosorbent assay (iELISA) based on a recombinant capsid (Cap) protein for sensitive and specific detection of antibodies against DuCV. Materials and Methods: The cap gene from a Thai DuCV genotype I isolate was cloned into the pQE-31 vector and expressed in Escherichia coli M15. The 27 kDa recombinant Cap protein was purified under denaturing conditions, and its antigenicity was confirmed by Western blotting. The iELISA was optimized by checkerboard titration to determine the optimal antigen coating concentration and serum dilution. Diagnostic sensitivity, specificity, cross-reactivity, repeatability, reproducibility, and agreement with Western blotting were assessed using 80 positive, 103 negative, and 189 field serum samples. Results: The optimized iELISA used 12 μg/well of antigen and a 1:20 serum dilution, producing the highest positive-to-negative optical density ratio. Receiver operating characteristic curve analysis yielded an area under the curve of 0.996, with 97.5% sensitivity and 98.1% specificity. No cross-reactivity was detected with sera positive for duck Tembusu virus, duck viral enteritis virus, or Riemerella anatipestifer. Intra- and inter-assay coefficients of variation were below 6.5% and 9.1%, respectively. Diagnostic agreement with Western blotting across 189 field sera was 91.0%, with a Cohen’s kappa of 0.752, indicating substantial concordance. Conclusion: The developed recombinant Cap-based iELISA provides a reliable, specific, and reproducible tool for large-scale DuCV serosurveillance. Its high diagnostic accuracy and scalability support its application in flock-level monitoring, pre-movement screening, and epidemiological studies, facilitating improved biosecurity and informed disease control strategies within the duck industry. Keywords: capsid protein, duck circovirus, indirect enzyme-linked immunosorbent assay, recombinant protein, serodiagnosis.

Encephalitozoon cuniculi causes both clinical and subclinical infections in rabbits, complicating a diagnosis due to the limitations of conventional tools like ELISA. This study analyzes serum proteomic profiles across clinical, subclinical, and healthy rabbits to identify discriminatory biomarkers. Serum from 90 pet rabbits (30 per group) was pooled (10 samples per pool, 3 pools per group) and analyzed using one-dimensional gel electrophoresis and mass spectrometry. The proteomic analysis revealed 109, 98, and 74 proteins expressed in healthy, subclinical, and clinical groups, respectively. Of these, 50, 40, and 33 proteins were unique to the healthy, subclinical, and clinical groups, respectively, with only 10 proteins shared across all. A total of 88 proteins were differentially expressed in infected groups compared to healthy controls. Importantly, 12 proteins were consistently upregulated in both subclinical and clinical infections. These include markers related to the immune response (beta-2-microglobulin, alpha-2-HS-glycoprotein), coagulation (antithrombin-III, alpha-1-antiproteinase S-1), vitamin A transport (retinol-binding proteins), lipid metabolism (apolipoprotein C-III), cytoskeletal regulation (actin-depolymerizing factor), extracellular matrix integrity (fibrillin 2), and oxidative stress (monooxygenase DBH-like 1). Additionally, Gc-globulin and ER lipid-raft-associated 1 were linked to immune modulation and signaling. These findings identify specific serum proteins as promising biomarkers for distinguishing subclinical from clinical encephalitozoonosis in rabbits, enabling an early diagnosis and effective disease monitoring.