The objective is to maintain a steady target growth rate, overfeeding and underfeeding are both detrimental to future performance. Limit the number of breeding females to no more than 30 in the first season.
After the first breeding season bulls will be expected to continue to grow towards their mature weight at 3-years-old and should be fed accordingly. Make a note to check bull condition and adjust the ration if needed at least once a month.
Depending on temperament, bulls can be group housed but care must be taken to monitor for bullying which can limit feeding and may cause physical damage. Bull pens that allow single housing but a line of sight to other bulls or cows are ideal. Housing should ensure that bulls have room to exercise and that their feet are kept clean and dry.
Selecting yearling bulls for a minimum scrotal circumference of 34cm means that they will achieve higher pregnancy rates than bulls with smaller testicle size, so reducing calving spread. In the UK not enough emphasis is put on selecting bulls to this standard or semen testing them prior to use, with the result that there are too many sub-fertile bulls around contributing to extended calving spreads and more barren cows
Records show that hybrid bulls on average achieve a 30% increase in pregnancy rates over a 6 week breeding period than do pure-bred bulls.
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