Conservation & local programs

Phenotypic and genetic exploration of first- and second-generation progeny sired by gene bank collection bulls

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Abstract

A common perception is that germplasm collected and stored by gene banks will become outdated as the genetic composition of in-situ population changes via artificial or natural selection; therefore, limiting its use. Our objective was to evaluate performance and genetic structure of progeny and grand-progeny sired by Holstein and Angus collection bulls born 28 to 60 years ago. Germplasm from two 1960 era Holstein bulls was requested by a researcher to evaluate differences among bulls with Y-chromosomes no longer present from the current Holstein population. An elite Angus breeder, producing 8,000 bulls per year, requested and received samples from four bulls (born from 1958 to 1997) to perform corrective mating in their herd. For Holstein 128 progeny and grand-progeny daughters of collection bulls, were characterized, genotyped (777K SNP) and compared to 172 contemporary genetic cows in herds located in New Mexico and Pennsylvania. Angus collection bull progeny (n = 214) were compared to contemporary genetic herdmates (n = 4791) all within the breeder's nucleus herd; a 40K commercial SNP panel was used for genotyping. Milk yield for first generation Holstein exceeded contemporary genetic herdmates for milk production and second-generation progeny did not differ from herdmates in New Mexico and Pennsylvania. For Angus, old sire progeny phenotypic and genetic comparisons were competitive to contemporary genetic herdmates. Angus progeny from collection bulls had a lower number of ROH length (116.8 Mb) when compared to the top and bottom 10% of the modern in-situ contemporaries; 420 Mb and 434 Mb respectively. Holstein, sired by collection bulls had lower ROH among progeny (210 Mb) and grand progeny (320 Mb) compared to modern genetic contemporaries (506 Mb). The phenotypic performance for collection bull progeny was unexpected, especially among the two most intensely selected cattle breeds. These findings suggest by using older collection bulls from the gene bank that heterozygosity was increased among resulting progeny and contributed to higher levels of performance than expected. Other factors may also be impacting performance including recombination effects and utilizing high performing dams as mates. These results suggest animals with samples maintained in gene banks may have utility for any number of purposes among current in-situ populations. Therefore, concerns about substantially lower performance levels from gene bank progeny are not well founded. The findings also suggest that gene bank holdings from various unique breeds or subpopulations within a breed warrant deeper exploration to better understand changes in genetic diversity and pathways for increasing animal productivity at the genetic level.

Keywords: 2026

How to Cite:

Blackburn, H., Hay, E. & Dechow, C., (2026) “Phenotypic and genetic exploration of first- and second-generation progeny sired by gene bank collection bulls”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2293555. doi: https://doi.org/10.31274/wcgalp.24315

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