Answering The Question: Is It A Miniature Hereford Or A Dwarf?

Miniature Herefords are growing in popularity but the question still remains: "Are they just tiny cattle or are they dwarfs?"

1.Miniature Herefords are registered with the American Hereford Association

Via Boden, D. W. R. 2008. Miniature cattle: For real, for pets, for production. J. Agric. Food Information 9:167-183.

Miniature Herefords share a breed registry with their larger, full-sized counterparts. However, there are some specific criteria set forth by the breed association. Miniature Herefords must be red with white faces and can be horned or polled. To classify as miniature they must have a 0000-0 frame score (Full size Herefords range from about a 4-10 frame score), which means the tallest a mature female Miniature Hereford can ever be is 43 inches! It is estimated there are about 3,000 head of Miniature Herefords registered in the United States.

Boden, D. W. R. 2008. Miniature cattle: For real, for pets, for production. J. Agric. Food Information 9:167-183.

2.Miniature does NOT equal dwarf

Cattle of the 1950’s and 60’s were selected for a more moderate size. These cattle were sometimes referred to as “belt-bucklers” because they were so short they would only come up to a person’s belt buckle! Unfortunately this phenotypic selection also led to an increased frequency of abnormal dwarfism during that period. This leads to confusion as to whether miniature Herefords are actually miniature or dwarves. However, to be a registered miniature Hereford they must come from a certified dwarf-free Hereford bloodline. Though smaller in size, a miniature Hereford’s body is still completely proportional.

Boden, D. W. R. 2008. Miniature cattle: For real, for pets, for production. J. Agric. Food Information 9:167-183.

3.There are two types of dwarfism in Herefords

The first is long nosed dwarfism, where cattle are abnormally small, however bone growth of the head is not affected. This is inherited as an autosomal recessive mutation. The second type of dwarfism is Snorter dwarfism which is easily identified as cattle have abnormally short heads. This shortening of the head causes abnormal breathing causing the cattle to snort. These cattle also have shortened long bones in their legs. Snorter dwarfism is also inherited by an autosomal recessive gene.

Gregory, K. E. and S. L. Spahr. 1979. Miniature calves. J. Heredity. 70:217-219.

4.The dwarfism gene can be traced all the way back to one bull

The American Hereford Association hired L. P. McCann as director of research to track down the origin of dwarfism in Herefords. Using extensive pedigree research he traced the genetic mutation to a bull name St. Louis Lad. This is truly impressive because this was long before the time of computerized pedigree analysis and modern electronic communication! However, because this mutation also occurred long before the time of genetic testing a defect-free status was difficult to prove. Also, Herefords that were heterozygous for the gene (had only one mutated gene) had phenotypes that were so varied they could not be identified. Therefore, the Hereford Association opted to eliminate entire breeding lines from their registry, virtually eliminating the problem from the breed!

Whitlock, B. K., L. Kaiser, and H. S. Maxwell. 2008. Heritable bovine fetal abnormalities. Theriogenology. 70:535-549.

We still don’t know exactly what genes cause this mutation in Herefords

The Hereford breed has done such a great job eliminating the mutation that now in the era of genetic testing, there are basically no genes to test! However, a few long nosed dwarves have still been identified in the Angus breed of cattle and finally in 2007, scientists at Iowa State University were able to identify that the mutation occurred within exon 15 of the cyclic GMP dependent type-II protein kinase gene (PRKG2). This gene is responsible for chondrocyte maturation, meaning that when this gene is mutated there is decreased long bone growth due to premature calcification of chondrocytes! However, scientists don’t know if this is the same gene that caused dwarfism in Herefords.

Whitlock, B. K., L. Kaiser, and H. S. Maxwell. 2008. Heritable bovine fetal abnormalities. Theriogenology. 70:535-549.