Here is a brief introduction to both the Kedaka line of Tottori Prefecture and the Dai 7 Itozakura line of Shimane Prefecture (with a mention of Okayama Prefecture’s claim on Dai 7 Itozakura).
The Kedaka line started, appropriately enough, with the birth of bull Kedaka, himself, in Tottori Prefecture in 1959. Kedaka produced a number of fine lines and bulls, including the Harumi line (Shimane Prefecture). Kedaka cattle were bred as pack animals, so they were valued for their ability to transport things (produce, in this case) over great distances, rather than their ability to do heavy work over short distances. There was less of an emphasis on farm chores in Tottori Prefecture as there was in Hyogo Prefecture, so the cattle were built differently. Tottori Prefecture cattle didn’t need large forequarters but did need to be good grazers. Good grazing meant strong mothering instincts, something the Harumi line is widely appreciated for.
The Dai 20 Hirashige line, established in 1974, is the most famous offshoot of Kedaka’s genetics.
Interestingly, Dai 20 Hirashige is the product of a father-daughter mating. As a result, his “inbreeding coefficient” is 25 percent, at a minimum. An inbreeding coefficient estimates the percentage of identical genes that have been inherited or are likely to be inherited from an offspring’s parents.
An inbreeding coefficient can range from 0 to 100 percent, but 25 percent is considered to be high. Ideally, the inbreeding coefficient should not be higher than 12-15 percent. The higher the inbreeding coefficient is, the greater the risk of mortality or abnormality in offspring. On the other hand, a higher inbreeding coefficient can enhance the positive traits of the two parents in the progeny.
It’s a roll of the genetic dice, but often the potential benefits are judged to be worth the possible risks.
For more information about inbreeding, line breeding and inbreeding coefficient, click here.
As the 20th century progressed, Tottori Prefecture began to provide more bulls for other prefectures — and even other continents (namely, Australia) — than it did for itself. In fact, some of the finest Tottori lines were launched outside of Tottori. For example, Hirashigekatsu, of Kagoshima Prefecture, is one of the best and most balanced bulls in current use. Taro Araki, publisher of Beef Cattle magazine, has said that Hirashigekatsu is an ancestor of half the cows in Japan.
Today, Tottori is trying to get some of its genetics back to bolster its own herds.
The Kedaka chart is as follows:
The Dai 7 Itozakura line is really two lines and two prefectures joined by a common ancestor: Dai 14 Shigeru. In Shimane Prefecture, Dai 14 Shigeru (who was born in Okayama Prefecture) was paired with a Tajima dam to create Dai 7 Itozakura. In Okayama Prefecture, descendants of Dai 7 Itozakura — Dai 6 Fujiyoshi, in particular — were used to create the Fujiyoshi line.
As Shogo Takeda wrote in the August 2007 issue of the Australian Wagyu Update, “People from Okayama Prefecture insisted that Dai 7 Itozakura originated from the Okayama line. This is because Dai 7 Itozakura’s sire (Dai 14 Shigeru) was born in Okayama. On the other hand, people from Shimane Prefecture insisted that Dai 7 Itozakura originated from Shimane, as his maternal lines originated from Shimane.”
Dai 7 Itozakura’s most famous son is, perhaps, Kitaguni 7-8, whose mother was a Kedaka dam. Thus, Kitaguni 7-8 was a Dai 7-Kedaka composite bull.
The Dai 7 Itozakura (Shimane) chart is as follows: