More data out of the lectures we attended this weekend.
Dr Larry Cundiff, MARC was discussing heterosis and crossbreeding.
Heterosis comes from crossing cattle with more "unlike alleles". He said there is less heterosis "kick" with Herefords in the cross than Angus.
He explained that each allele was either Heterozygous or Homozygous for that trait. The more hetero alleles, the more heterosis. (there are MANY alleles)
In development of the Hfd, they had to have Homo gene for color, Homo gene for white face, Homo gene for white bellie, Homo gene for white legs, tail, etc. Making it more difficult to get them "true" to the breed.
The Angus only had to worry about 2 genes that had to be Homo - black & polled. Therefore there was less "outside" influence of genes throughout the growth of the breeds. If the neighbors Holstein jumped the fence, the owner of the Angus wouldn't know by looking at the calves because they would be black & polled, so he could assume them were PB. If that happened to the Hereford herd, the calves would be black, so they knew they weren't pure. Therefore, he said, the Herefords are more Homozygous in all their alleles and Angus are less Homo in their alleles, making the Angus better for heterosis.
Dr Larry Cundiff, MARC was discussing heterosis and crossbreeding.
Heterosis comes from crossing cattle with more "unlike alleles". He said there is less heterosis "kick" with Herefords in the cross than Angus.
He explained that each allele was either Heterozygous or Homozygous for that trait. The more hetero alleles, the more heterosis. (there are MANY alleles)
In development of the Hfd, they had to have Homo gene for color, Homo gene for white face, Homo gene for white bellie, Homo gene for white legs, tail, etc. Making it more difficult to get them "true" to the breed.
The Angus only had to worry about 2 genes that had to be Homo - black & polled. Therefore there was less "outside" influence of genes throughout the growth of the breeds. If the neighbors Holstein jumped the fence, the owner of the Angus wouldn't know by looking at the calves because they would be black & polled, so he could assume them were PB. If that happened to the Hereford herd, the calves would be black, so they knew they weren't pure. Therefore, he said, the Herefords are more Homozygous in all their alleles and Angus are less Homo in their alleles, making the Angus better for heterosis.