Investigation of acylcarnitine profile in naturally infected calves with Cryptosporidium parvum.

Cryptosporidium parvum (C. parvum) is one of the common infectious and zoonotic agents in neonatal calves. Carnitine is an important molecule of mitochondrial energy metabolism that can lead to metabolic and clinical disorders. This study aims to determine the carnitine and acylcarnitine profiles in calves infected with C. parvum, to evaluate their role in the pathogenesis of the disease, and to investigate their diagnostic effectiveness. A total of 32 calves were included in the study, 20 calves infected with C. parvum and 12 calves determined to be healthy, aged between 1 and 28 days. Blood samples were taken from all animals included in the study for biochemistry and carnitine analyses. Carnitine, propionylcarnitine, malonylcarnitine, iso-/butyrylcarnitine, 3-OH-iso-/butyrylcarnitine, tiglylcarnitine, isovaleryl-/2-methylbutyrylcarnitine, 3-OH-isovalerylcarnitine, hexanoylcarnitine, octanoylcarnitine, decanoylcarnitine, dodecanoylcarnitine, octadecenoylcarnitine, total carnitine, and acetylcarnitine levels were found to be significantly higher in the C. parvum infected group compared to the control group. According to receiver operating characteristic (ROC) analysis, carnitine (AUC=0.888), total carnitine (AUC=0.879), tiglylcarnitine (AUC=0.871), isovaleryl-/2-methylbutyrylcarnitine (AUC=0.871), 3-OH-iso-/butyrylcarnitine (AUC=0.863) decanoylcarnitine (AUC=0.852), acetylcarnitine (AUC=0.838), and 3-OH-isovalerylcarnitine (AUC=0.813) showed good diagnostic performance, while iso-/butyrylcarnitine (AUC=0.975), hexanoylcarnitine (AUC=0.971), and octanoylcarnitine (AUC=0.908), and malonylcarnitine (AUC=0.900) showed very good diagnostic performance. In conclusion, C. parvum mitochondrial dysfunction and impaired fatty acid oxidation, resulting from intestinal, kidney, and liver damage in infected calves, are thought to play a role in the pathogenesis of the disease as key mechanisms supporting the accumulation of carnitine and acylcarnitine.