Research conducted by Colorado State University and published in 1973 looked at parturition records of 2733 Hereford calves sired by 123 bulls and born to 778 cows or heifers.
linkResearch conducted by Colorado State University and published in 1973 looked at parturition records of 2733 Hereford calves sired by 123 bulls and born to 778 cows or heifers.
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