Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 12 1 2024 01 02 1 8 Hossein Esmaeili Department of Microbiology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran Ehsan Baghal Arani 1. Department of microbiology and immunology, Faculty of veterinary medicine, University of Tehran, Tehran, Iran Mohammad Reza Mokhber Dezfouli Department of Internal medicine, Faculty of veterinary medicine, University of Tehran, Tehran, Iran Seyed Mehdi Joghataei 1. Department of microbiology and immunology, Faculty of veterinary medicine, University of Tehran, Tehran, Iran Mahdi Ganjkhanlou Department of Animal Science, Campus of Agriculture and Natural Resources, University of Tehran, Karaj, Tehran 2023 04 28 2023 08 11 Background:   Infectious diarrhea in young goats is one of the most common and serious threats to the animals' health, influencing the profitability of the goat industry. Considering the need to investigate the factors involved in the occurrence of neonatal diseases, especially diarrhea, to improve livestock health and increase productivity, especially in Iran, the present study was conducted with the aim of investigating the bacterial agents involved in the diarrhea of Alpine and Saanen kids. Methods:   Between 1421 goats (714 Saanen and 704 Alpine) under the supervision, 254 goats (17.8%) of different ages died due to diarrhea sign. Samples from the liver, heart, and lungs were taken during the necropsy process, and bacteriological examinations were performed. Results:   Forty-four kids died of non-infectious cause. Diarrhea caused by bacterial agents (10.9%) was much more than non-infectious agents (3.1%). Significantly more so than at other ages, the bacterial agent was isolated from the age of less than 2 months. Isolated bacterial agents included Escherichia coli, Staphylococcus aureus (12.3%), Pseudomonas (7.1%), Bacillus (11%) and Klebsiella (2.6%). E. coli was isolated frequently (63.2%) , and mostly at the age of less than 2 months. The highest rate of isolation of bacterial agents was from the heart, especially E. coli. Conclusion:   The findings of the current research showed that in Saanen and Alpine goats reared in intensive rearing systems, E. coli bacteria has a high contribution to the occurrence of digestive problems and diarrhea, which can be avoided by controlling environmental health, improvement and preventing the density of parturitions in a short time. https://jmb.tums.ac.ir/index.php/jmb/article/view/487