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- SELECTING BEEF CATTLE Agriscience 332 Animal Science #8399 TEKS: (c)(7)(B)
- Introduction Knowledge of selection practices and how to properly apply them can help improve a producers herd genetics and economics. Photo by Bill Tarpenning courtesy of USDA Photography Center.
- Methods of Selection The methods of beef cattle selection that are used must support the goals of the production system type. The objectives of commercial cow/calf producers and purebred breeders are similar; however, the management practices may be quite different.
- The goal of most cow/calf producers is to produce the maximum pounds of calf at the most economical cost. Photo by Gary Kramer courtesy of USDA Natural Resources Conservation Service.
- The goal of the purebred breeder is to produce breeding cattle for purchase by other breeders and commercial cow/calf producers. Photo by Bill Tarpenning courtesy of USDA Photography Center.
- The three principle considerations for selection of breeding animals are: Visual appraisal, Pedigree, and Performance.
- Depending upon the producers objectives, varying degrees of emphasis are placed on the selection factors. For example, the purebred breeder often places more emphasis on pedigree than does the cow/calf producer.
- Visual Appraisal as a Basis of Selection Selection by visual appraisal has been responsible for much of the genetic improvement of beef cattle.
- Visual appraisal can be a good indicator of an individuals offspring characteristics, such as: Frame size, Muscle and body structure, Predisposition to waste, Feet and leg structure, and Breed character.
- A close relationship exists between the appearance of a breeding beef animal and its reproductive efficiency, a critical factor in the success of purebred and commercial operations. Breeding cattle must be able to reproduce regularly over a long period of time to be economically productive.
- An understanding of beef animal parts and their description is necessary for effective communication in any segment of the beef industry involving live cattle or carcass evaluation.
- The following characteristics should be visually appraised: Body structure, Soundness of feet and legs, Muscling and muscle structure, Frame or skeletal size, Reproductive soundness,
- Predisposition to waste, Breed character, Temperament, and Conformation score. These characteristics are then combined with production records and pedigree analysis for effectiveness in selecting beef breeding animals.
- Body Structure Body structure is a major factor in the visual evaluation of beef cattle. The general body structure of an animal is a good indicator of production characteristics.
- Cattle with the correct body structure will be more efficient producers, thus having more potential for economic returns. To evaluate body structure, look for the following factors in the animal.
- The neck of a beef animal should be moderately long, which is an indicator of growth; The animal should be clean in the throat area; The loin and rump should be long, wide, and level causing the animal to be long and strong in its back;
- Extremely short-bodied and short- legged cattle are associated with excessive fat deposition and inefficient growth rates; Long-legged and long-bodied cattle are associated with late maturity and low-quality grades;
- The round of beef cattle should be deep and wide when viewed from the rear, with the widest portion being about midway between the tail head and hock;
- The shoulder should be well- muscled, but free of coarseness; Offspring with extremely heavy, open shoulders can cause calving difficulties;
- A beef animal should be moderately trim in its rear flank, underline, and brisket, and carry minimal excessive waste; At the same time, the animal should show good depth of body, indicating body capacity and overall productiveness.
- An animal that has a wide, full heart girth, adequate spring of the fore-ribs, and a wide chest floor and chest indicates proper growth and function of vital organs; and Adequate width between front and hind legs also indicates good body capacity and muscling.
- Soundness of Feet and Legs Visual appraisal of structural soundness is useful in evaluating longevity and productivity. For cattle to travel and remain sound during long productive lives, they must have correct conformation of feet and legs.
- Factors to look for when evaluating soundness: The legs should be squarely set under the four corners of a beef animal and be reasonably straight; The shoulders should not be too straight, as this may be an indicator of leg problems; and
- Animals that exhibit signs of structural abnormalities should not be selected as potential breeding animals.
- Examples of common structural abnormalities of the feet and legs include: Post-legged hind legs are set too far back, thus making them too straight; Sickle-hocked hind legs are set too far under the body.
- Knock-kneed front legs are close at the knees and feet are toed-out. Pigeon-toed front feet are toed-in.
- Bow-legged hind legs are wide at the hocks and feet are toed-in. Cow-hocked hind legs are close at the hocks and feet are toed-out.
- An animals productive longevity is largely dependent on its structural soundness. Longevity is important in all phases of beef production because it affects the number of replacement animals needed to maintain a herd.
- An animals movement should be free and easy as opposed to being uncoordinated, slow, stiff, and restricted. Animals with uneven, small, curled, or twisted toes and crooked feet usually become lame and should not be selected.
- Unsound feet, legs, and joints affect the ability of bulls to follow and breed cows, which reduces herd productivity. Breeding animals with feet or leg problems are not physically capable of being productive over an extended period of time.
- Muscling and Muscle Structure Evaluating muscling is another important factor to consider when visually appraising beef cattle. Muscling is the source of meat for consumers and, therefore, is essential to evaluate.
- Muscling is indicated by: Conformation, Overall thickness and fullness, and Muscular development in relation to skeletal size.
- Bulls Thick, heavy, long muscling is desired by bulls and is indicated by: Length and size of muscling in the forearm and gaskin areas; Width and bulge of muscling in the stifle area as viewed from the rear and side;
- Width between the hind legs (both standing and walking); Thickness, length, and bulge of muscling in the back and loin; and Expression of muscling in the shoulder and round as the animal moves.
- Length of muscling is largely determined by length of bone. If muscling is thick and bulging in one area of an animals body, the animal is usually heavily muscled throughout the body.
- Animals with extreme muscling, to the point of being impaired in movement or appearing double- muscled, should not be selected. This Piedmontese-Hereford crossbred calf displays classic double muscling because it inherited a defective myostatin gene from both of its parents. (USDA-ARS) Photo by Keith Weller courtesy of USDA Agricultural Research Service.
- Cows and Heifers Muscling in females should be long, smooth, and of moderate thickness. In females, short, coarse, bully muscling is usually a sign of poor reproductive efficiency and low milking ability.
- A females overall body shape should have a slightly angular appearance, wit
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