It is often said that calving difficulty results from joining heifers when they are too young. In cases where heifers are accidentally mated at very light weights or young ages, high levels of calving difficulty attributable to a small, immature birth canal do occur. However, producers should not be deterred from joining well grown British breed heifers (minimum joining weight 275 kg, condition score 3), to calve at two years of age.
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