by Gáspárdy András*, Kaltenekker Endre, Borics Imre

SUMMARY

Background:

The Hungarian Grey Cattle is an important historical breed, one of the national treasures of Hungary. Today, the proportion of living representatives of the bull lines has become uneven. The strengthening of the rare bull lines (B, M, T and V) was initiated by the Hortobágy Nature Conservation and Gene Preservation Non-profit Ltd. and the Hungarian Grey Cattle Breeders Association.

Objectives:

This study reports on the experiences of the breeding program so far. The success of the breeding program is analysed by evaluating the birth of calves and their destination, and the genetic parameters in terms of changes in diversity.

Materials and Methods:

During the three year long (2020-2022) insemination program, cryopreserved semen was used from breeding bulls born in the 1970s. From 150 synchronized heifers 78 calves were brought into the world (2021-2023). Based on own performance testing, twelve young bulls were certified or licensed (central sire registration number).

Results and Discussion:

In terms of the generation interval, the father-offspring relationship resulted in a significantly (p < 0.001) longer period (43.9 years) than the mother-offspring relationship (4.2 years). The median inbreeding coefficient of calves born after the “archive bulls” is 2.859%, which is lower than the value of the reference stock (3.502%), and differs significantly (p = 0.002) from it. The common inbreeding coefficient of the qualified bulls (median 2.84%) is also significantly (p = 0.016) below the average relatedness between them (coancestry coefficient, median 3.84%). As a conclusion, it was possible to obtain 12 breeding bulls with low inbred status from mating of distantly related individuals. The implemented program not only revives rare sire lines, but also renews the genetic pool of the herd. However, the applied procedure revealed appearance of conformation faults and performance deficiencies that result in exclusion from breeding. The use of reproductive material from time to time also serves to verify the reliability of the sperm freezing- and storing technique.