The concentration of recombinant human lactoferrin in the milk of transgenic goats of the third and fourth year of lactation

The concentration of recombinant human lactoferrin (rhLF) in the milk of 22 transgenic goats of different ages was studied: the average concentration of rhLF in the milk of goats-producers of the 4th year of lactation was 13.7% higher than that of goats of the 3rd year of lactation (6.07 and 5.24 g/l, respectively). It was found that the maximum level of recombinant glycoprotein was produced by the mammary gland of animals in the 2nd and 4th quarters of the studied year period. Protein’s concentration in milk measured in the 2nd and 4th quarters was 6.4 g/l and 6.33 g/l for producers of the third year of lactation and 8.14 g/l and 7.02 g/l for goats of the fourth year of lactation, respectively. The correlation between the season of the year and the content of the target protein in milk was detected (p <0.01), it was found that the most active rhLF production in goat milk occurred in late spring and winter periods. Variability in the content of the protein of interest in milk between individuals was noted. During the study a relatively low level of rhLF was established in animal №0747 - 0.11–2.52 g/l, while its maximum value was detected in the producer № 0403 - 4.52–9.06 g/l (more than 4 times difference). The range of individual variability in terms of rhLF content in the milk of goats of the third and the fourth lactation was 0.11–9.06 g/l. Milk of genetically modified goats contains 3 times more lactoferrin than human breast milk. Therefore, rhLF concentration testing in goat milk and tracking the dynamics of this indicator allows us to obtain data that can be used later for breeding pro-grams formation, milk production planning and also to improve the gene pool of transgenic animals.