Birth Weights

Calf birth weight is a useful indicator of calving ease. Therefore, selection of breeding animals for smaller birth weight EPD is an effective criterion for improving direct calving ease. Birth weight measurements must be taken as soon after birth as possible, calves should also be weighed and then identified with a permanent identification number (tattoo) at this time. The dam ID, calf ID, date of birth, calving ease score, calf vigor, and dam’s udder score should also be recorded at this time.

Calving Ease Score

Producers are asked to score the degree of calving difficulty using the following guidelines:




Calf Vigor

Calf vigor is important to the survival and health of newborn calves. Calf vigor scores represents how long it takes a calf to get up and start nursing or if it needed assistance.




Teat & Udder Scores

Udder and teat quality definitely influence the profitability of beef production. Poor quality, injuries and/or disease of udders are a leading cause of culling and thereby lower cow longevity and lifetime productivity. Although larger udders have been associated with higher milk production and calf weaning weight, excessively large, pendulous udders and large teats may present difficulty for a calf to nurse, and thereby calf growth and weaning weight may be affected negatively. In general, more tightly supported udders and smaller teats should be considered desirable; however, the extremes of these conditions likely become detrimental at some point.

Deliberate, annual evaluation of udder quality is an essential component of cow-calf production. The Beef Improvement Federation recommends scoring udder suspension and teat size annually on cows within 24 hours of the cow giving birth. These subjective numerical scores (see table below) can easily be assigned in the pasture. Scores should be assigned according to the worst quarter of the cow’s udder. To ensure consistency and facilitate comparison of records, preferably one person should evaluate all cows each year and across years. Written notes about abnormal shapes or characteristics other than udder suspension and teat size may be useful. (BIF)

The two charts below are courtesy of the University of Nebraska Lincoln.



Individual Animal ID

A permanent ID is an identification number that will stay with the animal from birth to death, and will be transferred to a new owner. This is important for identification of animals, because if you rely on a less permanent ID system, such as ear tags, animals can lose tags and other less permanent forms of ID and subsequently their individual identification is lost.

Breeders are responsible for ensuring that the animals they register bear a form of permanent identification prior to application for registration. All registered animals must carry a tattoo in one or both ears. That must consist of the owner’s herd prefix, an individual animal identification (I.D.) number, and the appropriate year letter code. A maximum of nine (9) digits may be used, and no two animals may carry the same tattoo within the same herd. In the event a breeder utilizes freeze-brand marks as a permanent identification mark, such mark shall be placed once on either side of each individual animal. In the event that a breeder utilizes a hot-branded mark as a permanent identification mark, such mark shall be placed once on either side of each individual animal. Any combination of the above locations or methods may be used.

A Herd Prefix is assigned to each member when application for membership is submitted. Herd prefix must be a minimum of two (2) and not more than four (4) alphabetical letters. No two members may have or use the same herd prefix.

1. When registering a calf born to its natural mother, the herd prefix of the owner of the dam at the time of birth must be used, and that individual must register the calf before it can be transferred.

2. An embryo transfer calf must be tattooed with and registered with the herd prefix of the owner of the calf at the time of registration.

3. Under no circumstances should an individual attempt to register a calf with herd prefix that have not been approved and assigned by the AWA Registry Office, or herd letter of another member or breeder.

4. Individual Identifying Number This number should be such that no two animals may carry the same tattoo/brand, (herd prefix, I.D. numbers, and year letter code). A maximum of nine (9) digits may be used in the total tattoo (maximum of 4 digits for herd prefix, maximum 5 ID and year letter code).

5. Year letter code. Part of the required Wagyu Tattoo must be year letter code. Usually it is the last digit in the tattoo. Following are the year letter code codes from 2001 through the year 2030. (The letters I, O, Q, and V are not used).

Year Letter Codes

If any tattoo is un-readable and you are the breeder, re-tattoo the animal in a different lobe and notify the Association Office. If you put the wrong tattoo in an ear, don’t alter it. Send the Certificate of Registration to the Association for correction. If any tattoo in a purchased animal is not legible, or does not agree with the Certificate of Registration, contact the Association office.

Reporting information on ET calves

Embryo transfer calves can be included in the Wagyu National Cattle Evaluation. There is however additional information required before EPD can be computed. Information about the recipient cow is required; information needed is the breed of recipient cow, year of birth of recipient cow, and a permanent identification number for the recipient cow. Contemporary groups will be formed using the same guidelines as for natural calves with the addition of recipient cow information. For example, calves out of the same breed type of recipient dam will be in the same contemporary group while calves out of recipient dams of different breed types will be in different contemporary groups. Be sure to include this information when registering Embryo Transfer calves.

Reporting information for Twin Calves

Performance information for twin calves should be reported to the AWA. While at this time weaning and yearling information from twin calves is not used by National Cattle Evaluation for the evaluation of weaning, yearling or milk EPD, the birth information is usable. Birth EPD can be computed for twin calves in many cases.

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