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Show By Robert S. Murdock County Agricultural Agent DWARFISM IN BEEF CATTLE In this article I will try to give you an idea of the 'dwarf and its importance to the beef cattle industry. A type of dwarfism that is inherited, has been showing up more and more in beef cattle the past few years, especially in the purebred pure-bred herds. This dwarfism has been and will be of considerable consider-able economic importance, because be-cause many of these dwarfs die soon after birth, and if they do live to maturity, they are quite susceptible to bloat. Also it is obvious that even if dwarf cattle do attain their so-called maturity, the majority dwarfs will never come close to attaining attain-ing a desirable market weight or finish. Dwarf cattle are very easily identified. Most of them have short, broad heads, a bulging forehead, stunted growth, heavy breathing, pot bellies and an over-shot jaw, sometimes as much as a half-inch or more. As new-born calves, dwarfs are often very attractive because they look like outstanding prospects. pros-pects. The body proportions approach ap-proach those of mature animals rather than that of a calf and show characteristics as the typey, short, wide head, blockiness, short legs, and good fleshing. However, after two to three months of age, the dwarf calf takes on the other characteristics characteris-tics such as heavy and noisy breathing and becomes potbellied. Dwarfism in beef cattle is not confined to any one of the three major beef breeds. Dwarfism, Dwarf-ism, as previously mentioned, is inherited, and is caused by a simple recissive gene or hered-tary hered-tary characteristic and has definitely" defi-nitely" been identified in Here-fords, Here-fords, Angus and Shorthorns. Dwarf cattle do not all look the same or attain the same size. Observation has been made of dwarfs that were barely two feet tall at 18 months of age, and others that weighed 600 pounds at 18 months. Still others oth-ers appeared stunted or small for their age and looked quite normal in . every other respect But they still carried one or more of the characteristics of dwarfs. All dwarfs have bulging foreheads, fore-heads, and it was this one characteristic char-acteristic that led to a method of identification of carriers by Dr. P. W. Gregory, of the University Uni-versity of California, who has done the majority of research on dwarf cattle. The heterzy-gotes heterzy-gotes or normal appearing dwarf carriers also have what Dr. Gregory terms as a midforehead prominence. Not all of the true dwarfs have short wide heads. Angus and Shorthorn dwarfs have been observed that have fairly long, narrow heads, but they still have this midforehead midfore-head prominence or bulge. Dwarf carriers or heterzygo-tes heterzygo-tes have a bulge or midforehead prominence that is intermediate between that of a dwarf and a normal animal. Sometimes this bulge can be detected by the naked eye or by feel, but this method is far from reliable, and to say an animal is a carrier by this method would not be any better than a very bad guess. Dr. Gregory in his research to identify dwarf carriers has developed de-veloped an instrument called the profilometer, which makes it possible to get an accurate profile of an animal's head. Two profiles are taken and in this way he has been successful in determining the dwarf characteristics. charac-teristics. It appears that dwarfism will have to be lived with by the beef cattle industry for some time. Elimination of carrier bulls will be a slow process, let alone the females. Lines and families of pure or homozygous cattle for the absence of dwarfism dwarf-ism are relatively numerous, and identification of these as I well as carriers is important. It must be remembered that in families where dwarfism is a factor, these families also will produce homozygous of non-carrier non-carrier animals. There may be a tendency to condemn all animals ani-mals in strains of families of beef cattle producing dwarfs. This must not be done. An effort ef-fort must be made to identify the carrier animals within these families and eliminate them. 1 |