03188naa a2200349 a 450000100080000000500110000800800410001902200140006002400350007410000180010924501400012726000090026750003240027652018040060065300260240465300110243065300150244165300140245665300560247065300180252665300140254470000160255870000140257470000140258870000150260270000180261770000170263570000190265270000180267170000150268977301340270410644412024-01-29       2024    bl uuuu     u00u1 u    #d  a1040-63877 a10.1177/104063872312157562DOI1 aGARCÍA, J.A.  aPollen beetle (Astylus atromaculatus)-associated gastroenteric disease in cattlebreport of 6 natural outbreaks.h[electronic resource]  c2024  aArticle history: Article first published online: November 29, 2023; Issue published: January 2024. -- Correspondence: Uzal, F.A.; California Animal Health and Food Safety Laboratory, San Bernardino branches, School of Veterinary Medicine, University of California, Davis, CA, United States; email:fauzal@ucdavis.edu  --  aABSTRACT.- Astylus atromaculatus is a pollen beetle native to South America, commonly found in crop flowers. Experimental intoxication of sheep and guinea pigs by this beetle resulting in fibrinonecrotizing enteritis has been reported. We describe here 6 natural outbreaks of intoxication in cattle associated with consumption of alfalfa (5 of 6) and mixed native (1 of 6) pastures heavily contaminated with A. atromaculatus. The outbreaks occurred during the summer (January-February) of 2023 in Argentina (n = 4) and Uruguay (n = 2), in beef cattle under extensive or semi-extensive rearing systems, with overall cumulative incidence and mortality of 22.3% and 17.8%, respectively. The main clinical signs included acute onset of anorexia, lethargy, hyperthermia, hindlimb weakness, reluctance to move, and diarrhea, for up to 15 d. In 2 outbreaks, sudden death was observed. Eight Hereford, Angus, and/or crossbreed heifers, cows, steers, and/or calves were autopsied. Gross and microscopic findings included multifocal necrosis with fibrinous pseudomembranes in the forestomachs and/or small and large intestines. Fragments or whole specimens of A. atromaculatus were identified in the ruminal content of all animals. Testing for multiple gastroenteric pathogens was negative as was testing of A. atromaculatus for cantharidin and batrachotoxin. GC-MS and LC-MS/MS performed on the beetles did not identify any known toxic compounds. Based on the exposure to A. atromaculatus-contaminated pasture, gross and microscopic lesions, and negative results of all testing for multiple gastroenteric pathogens, a diagnosis of intoxication by A. atromaculatus is proposed. Disease caused by A. atromaculatus consumption has not been reported previously in cattle, to our knowledge. © 2023 The Author(s).  aAstylus atromaculatus  aCattle  aColeoptera  aEnteritis  aPLATAFORMA DE INVESTIGACIÓN EN SALUD ANIMAL - INIA  aPollen beetle  aRumenitis1 aLIVIO, J.M.1 aMATTO, C.1 aDUTRA, F.1 aSCIOLI, V.1 aGIANNITTI, F.1 aLANGSTON, J.1 aPOPPENGA, R.H.1 aCANTÓN, G.J.1 aUZAL, F.A.  tJournal of Veterinary Diagnostic Investigation, 2024, Volume 36, Issue 1, Pages 95-102. https://doi.org/10.1177/10406387231215756