Bovine respiratory syncytial Virus (BRSV) infection detected in exhaled breath condensate of dairy calves by near-infrared aquaphotomics

Authors: SANTOS-RIVERA, MARIANA - Mississippi State University; WOOLUMS, AMELIA - Mississippi State University; THORESON, MERRILEE - Mississippi State University; MEYER, FLORENCIA - Mississippi State University; VANCE, CARRIE - Mississippi State University

Submitted to: Molecules
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/13/2022
Publication Date: 1/16/2022
Citation: Santos-Rivera, M., Woolums, A.R., Thoreson, M., Meyer, F., Vance, C.K. 2022. Bovine respiratory syncytial Virus (BRSV) infection detected in exhaled breath condensate of dairy calves by near-infrared aquaphotomics. Molecules. 27(2):549-562. https://doi.org/10.3390/molecules27020549.
DOI: https://doi.org/10.3390/molecules27020549

Interpretive Summary: Bovine respiratory disease (BRD) casued by bovine respiratory syncytial virus (BRSV) manifests as pneumonia and can be difficult to diagnose in asymptomatic animals, yet can be easily transmitted throughout a herd. Low level infection of BRSV can be detected in breath condensate captured non-invasively from young calves, using near-infrared spectroscopic methodologies and machine learning to distinguish diseased from healthy animals. Spectra collected on breath condensate was evaluated for changes in the water spectral signature bands (C1-C-13) using a new approach called aquaphotomics, which has been used for diagnosis of fungal and viral infection in plants. Aquaphotomics modeling for infection by BRSV gives discrimination of infection with an accuracy, sensitivity and specificity of greater than 90%,a significant improvement over traditional diagnostic procedures only capable of reliably identifying 65% of infected animals. Near infrared spectroscopy has potential for real time application of respiratory viral infection in live animals on the farm.

Technical Abstract: Bovine respiratory syncytial virus (BRSV) is a major contributor to respiratory disease in cattle worldwide. Traditionally, BRSV infection is detected based on non-specific clinical signs, followed by reverse transcriptase-polymerase chain reaction (RT-PCR), the results of which can take days to obtain. Near-infrared aquaphotomics evaluation based on biochemical information from biofluids has the potential to support the rapid identification of BRSV infection in the field. This study evaluated NIR spectra (n = 240) of exhaled breath condensate (EBC) from dairy calves (n = 5) undergoing a controlled infection with BRSV. Changes in the organization of the aqueous phase of EBC during the baseline (pre-infection) and infected (post-infection and clinically abnormal) stages were found in the WAMACS (water matrix coordinates) C1, C5, C9, and C11, likely associated with volatile and non-volatile compounds in EBC. The discrimination of these chemical profiles by PCA-LDA models differentiated samples collected during the baseline and infected stages with an accuracy, sensitivity, and specificity >93% in both the calibration and validation. Thus, biochemical changes occurring during BRSV infection can be detected and evaluated with NIR-aquaphotomics in EBC. These findings form the foundation for developing an innovative, non-invasive, and in-field diagnostic tool to identify BRSV infection in cattle.