Researchers in St. Petersburg identified hidden liver diseases in cows using caffeine.

The study was conducted by specialists from the Department of Pharmacology and Toxicology at St. Petersburg State Academy of Veterinary Medicine. The results were published in the third issue of the “International Bulletin of Veterinary Medicine.” The research was supported by a grant from the Russian Science Foundation.

The research took place at a dairy farm in the Pskov region. Scientists monitored the caffeine elimination process in 40 Holstein cows, approximately one year old, with an average productivity of up to 5,500 liters of milk per year. The animals were divided into two groups of 20 individuals each. In the experimental group, the cows were administered a safe dose of caffeine—five milligrams per kilogram of body weight—after which blood samples were taken eleven times over the course of a day to determine caffeine concentration.

“The relevance of studying such tests in veterinary medicine has significantly increased in recent years due to the rise in animal diseases. Our method enables the early diagnosis of liver diseases when they cannot yet be identified by other means,” explains Olga Popova, Candidate of Veterinary Sciences and Associate Professor at the Department of Pharmacology and Toxicology at St. Petersburg State Academy of Veterinary Medicine.

The study showed that caffeine elimination in healthy cows occurs sequentially and linearly. The scientists established standard indicators for this process, which can now be used for comparison with sick animals to identify deviations in liver function.

The unique aspect of the method is that caffeine binds minimally to blood proteins and is metabolized directly through the liver. This makes it an ideal marker for assessing liver function. Changes in the rate of caffeine elimination may indicate liver dysfunction even before other symptoms appear.

As part of the study, the researchers analyzed three key indicators: the rate of caffeine elimination from the blood, the duration of its presence in the body, and its distribution across tissues. This data allows for an assessment of how effectively the liver performs its detoxification function.

Future research plans include the development of so-called “caffeine” curves—graphs illustrating the dynamics of caffeine elimination based on time and dose. This will enable conclusions regarding the functional state of the liver by analyzing how the substance is excreted from the body.

The research was carried out by Olga Popova, Candidate of Veterinary Sciences and Associate Professor, Vladimir Ponomarev, Candidate of Veterinary Sciences and Senior Lecturer, Anna Kostrova, a postgraduate student, and Lyubov Agafonova, a research applicant.