Development of a nutrient medium component from biological fluids of the reproductive system of cows to increase the efficiency of in vitro production of bovine embryos

The objective of the study is to create an effective system for obtaining bovine embryos by improving in vitro nutrient media. Objectives: to evaluate the use of biological fluids of the bovine reproductive tract in obtaining embryos using the in vitro method; to develop an optimal method for obtaining bovine biological fluids; to develop an optimal method for preparing a nutrient medium component based on biological fluids; to study a suitable concentration of a nutrient medium component based on biological fluids for adding to nutrient media; to compare the quality of embryos obtained in nutrient media with the addition of the de-veloped component and in nutrient media without the addition of the component; to compare groups with different additions of biological fluids and to identify the most optimal dosage; to compare the percentage of embryos that have reached the blastocyst stage and the percentage of blastocysts suitable for trans-plantation in the group with the addition of oviduct and uterine fluid and in the group without the addition of fluids. The object of the study is bovine oocyte-cumulus complexes. Ten heads of black-and-white Holsteinized cattle were selected for the experiment on collecting uterine fluid. The method chosen for col-lecting uterine fluid was aspiration of a sample from the uterine horns. To collect oviduct fluid, a method of sampling after animal slaughter was chosen. As a result of the research, an optimal method for collecting biological fluids was developed based on a modification of the Foley catheter. The improved device al-lowed collecting 30 ml more solution than the original device. Direct addition of the developed component to the nutrient media increased the yield of high-quality embryos; in the experimental group, this figure reached 64 %.