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Rationale: Mass spectrometry imaging (MSI) elevates the power of conventional mass spectrometry (MS) to multidimensional space, elucidating both chemical composition and localization. However, the field lacks any robust quality control (QC) and/or system suitability testing (SST) protocols to monitor inconsistencies during data acquisition, both of which are integral to ensure the validity of experimental results. To satisfy this demand in the community, we propose an adaptable QC/SST approach with five analyte options amendable to various ionization MSI platforms (e.g., desorption electrospray ionization, matrix‐assisted laser desorption/ionization [MALDI], MALDI‐2, and infrared matrix‐assisted laser desorption electrospray ionization [IR‐MALDESI]). Methods: A novel QC mix was sprayed across glass slides to collect QC/SST regions‐of‐interest (ROIs). Data were collected under optimal conditions and on a compromised instrument to construct and refine the principal component analysis (PCA) model in R. Metrics, including mass measurement accuracy and spectral accuracy, were evaluated, yielding an individual suitability score for each compound. The average of these scores is utilized to inform if troubleshooting is necessary. Results: The PCA‐based SST model was applied to data collected when the instrument was compromised. The resultant SST scores were used to determine a statistically significant threshold, which was defined as 0.93 for IR‐MALDESI‐MSI analyses. This minimizes the type‐I error rate, where the QC/SST would report the platform to be in working condition when cleaning is actually necessary. Further, data scored after a partial cleaning demonstrate the importance of QC and frequent full instrument cleaning. Conclusions: This study is the starting point for addressing an important issue and will undergo future development to improve the efficiency of the protocol. Ultimately, this work is the first of its kind and proposes this approach as a proof of concept to develop and implement universal QC/SST protocols for a variety of MSI platforms. [ABSTRACT FROM AUTHOR]

A weak dromedary calf with signs of prematurity was born in April of 2023 to a healthy multiparous camel with a good body condition. The calf was diagnosed strongly positive to Trypanosoma evansi by haematocrit centrifugation technique (immediately after birth). The mother at that time was asymptomatic and negative by haematocrit centrifugation technique and PCR of blood. Indirect ELISA of the calf's serum before colostrum ingestion showed negligible levels of antibodies. However, 12 hours after colostrum ingestion and without any treatment, the levels of antibodies increased significantly, which coincided with negative haematocrit centrifugation technique. This indicates a possible role of colostral antibodies in neutralising the trypanosomes in the calf's blood. Examination of the placenta showed placentitis, and PCR confirmed a positive result for Trypanosoma nucleic acid. The importance of vertical transmission in maintaining the infection in a herd is discussed, as well as the role of colostrum in decreasing calf mortalities due to trypanosomosis. [ABSTRACT FROM AUTHOR]