Posted: Tue Aug 23, 2005 12:54 pm
I thought this extract from the NZ rare breeds site might be of interest to newcomers (like me) to the idea of grading up.
' Grading Up – Dexter Cattle
To begin grading up you require a purebred Dexter bull (or semen for AI) plus one or more suitable base cows of another breed. Ideally, these base cows will be of breed that reflects some of the characteristics of Dexters – that is, they are relatively small in size and of a solid colour. Suggested suitable breeds include Angus, Red Poll, and Jersey. (Most unsuitable are large, broken-coloured breeds such as the Friesian.)
The purebred Dexter bull is mated to these cows. Any resulting bull calves are discarded from the breeding programme, but the heifers are retained. These female animals are 50% Dexter and 50% of the base breed; they are known as Grade One (G1) Dexters. These are in turn mated to a purebred Dexter bull and the heifer calves are retained as Grade Two Dexters which are statistically 75% Dexter and 25% base breed.
By continually repeating the above process an animal is eventually obtained which at Grade Four which is almost 95% Dexter. At this level heifers can be admitted to the Herd Book as purebreds. Bulls, however have to be taken to Grade Five (97%) before being considered purebred.'
' Grading Up – Dexter Cattle
To begin grading up you require a purebred Dexter bull (or semen for AI) plus one or more suitable base cows of another breed. Ideally, these base cows will be of breed that reflects some of the characteristics of Dexters – that is, they are relatively small in size and of a solid colour. Suggested suitable breeds include Angus, Red Poll, and Jersey. (Most unsuitable are large, broken-coloured breeds such as the Friesian.)
The purebred Dexter bull is mated to these cows. Any resulting bull calves are discarded from the breeding programme, but the heifers are retained. These female animals are 50% Dexter and 50% of the base breed; they are known as Grade One (G1) Dexters. These are in turn mated to a purebred Dexter bull and the heifer calves are retained as Grade Two Dexters which are statistically 75% Dexter and 25% base breed.
By continually repeating the above process an animal is eventually obtained which at Grade Four which is almost 95% Dexter. At this level heifers can be admitted to the Herd Book as purebreds. Bulls, however have to be taken to Grade Five (97%) before being considered purebred.'