Evaluation of intestinal epithelial barrier and intestinal permeability in calves with neonatal diarrhea

Objective: The aim of this study is to investigate the changes in serum Zonulin and dAo levels in calf diarrhea cases, aiming to fill the gap in the literature and achieve results that can be applicable in practical field settings. Material and Methods: The animal material of the study consisted of 61 calves with neonatal diarrhea (acute diarrhea) in Aydın province, either from calf farms or from the Faculty of Veterinary Medicine at Aydın Adnan Menderes University. These calves were between 1-28 days old and had been diagnosed with relevant diseases through rapid diagnostic test kits. Both genders and various age groups were included in the study. Descriptive statistics, Kruskal-Wallis ANOVA and Mann-Whitney U tests were used for data analysis. Results: In this thesis study, serum levels of dAo (Diamine Oxidase) and zonulin were examined among different infection groups. The groups investigated were Cryptosporidium spp., E. coli, Cryptosporidium + Clostridium perfringens, E. coli + Clostridium perfringens, Cryptosporidium + Coronavirus, and a healthy control group. The serum levels of dAo and zonulin were measured for each group. The results were as follows: In the Cryptosporidium spp. group, the serum dAo level was measured as 7.97 ± 1.86 ng/mL and the serum zonulin level was found to be 46.71 ± 5.81 ng/mL. In the E. coli group, the serum dAo level was determined as 5.6 ± 0.59 ng/mL, while the serum zonulin level was observed to be 76.64 ± 2.80 ng/mL. The Cryptosporidium + Clostridium perfringens group exhibited a serum dAo level of 7.99 ± 0.55 ng/mL, and a serum zonulin level of 57.14 ± 8.98 ng/mL. Similarly, the E. coli + Clostridium perfringens group displayed a serum dAo level of 7.38 ± 0.72 ng/mL and a serum zonulin level of 36.56 ± 6.88 ng/mL. In the Cryptosporidium + Coronavirus group, the serum dAo level was measured as 3.767 ± 0.78 ng/mL and the serum zonulin level was determined to be 46.71 ± 7.11 ng/mL. The healthy control group exhibited a serum dAo level of 16.91 ± 1.09 ng/mL and a serum zonulin level of 35.69 ± 3.69 ng/mL. Conclusion: These findings suggest that infections may have an impact on intestinal barrier function, and serum zonulin levels may reflect this effect.