Reference intervals of mass coefficients of internal organs of hamster organs and their absolute values

To estimate the influence of a drug on the internal organs of animals and discover the target organs in toxicological studies, an organ mass analysis is required. The current article represents the referential intervals for the absolute values and the mass ratios of the organs of Syrian (golden) hamsters (Mesocricetus auratus). Data on the organ masses was received from control and intact mature animals used in the studies carried out in Research and manufacturing company “Home оf Pharmacy” in the period of 2019 to 2023. Age of the animals at the time of necropsy was between 8 and 27 weeks (1,5 to 6 months). According to the recommendations of The Society of Toxicologic Pathology the rodents had the following organs’ masses registered: liver, heart, kidneys, brain, spleen, thymus, testicles, adrenals. Additionally, the masses of lungs and ovaries were analyzed. Multiple calculation methods are used for organ masses analysis. Absolute values of the organ masses can differ heavily depending on the animal weight, so mass ratios of organs calculated relative to the mass of the body are used more commonly for proper estimation. Considering that in experiments, young animals are used, their body mass grow can have a more noticeable dynamic, which can cause false positive results when estimating the influence on the organs. In the presence of noticeable changes of the body mass it is more practical to use the organ mass ratio calculation relative to the brain mass as brain mass has low changeability in cases of body mass changeability. Therefore, absolute organ mass values and organ mass ratios calculated relatively to body and brain masses were used for the creation of referential intervals. In the sampling by absolute organ mass values and mass ratios of organs the number of values was more than 120 for the most part, considering the exclusion of statistic emissions. The number of values 120 is the minimal value for the calculation of referential intervals using the nonparametric method. Also, as some of the values of mass ratios and absolute organ values have abnormal distribution, the nonparametric method is preferable. Common number of emissions received during the analysis of absolute values and the calculation of organ mass ratios relative to the body mass and brain mass did not differ between males and females.