Double R Ranch – Replacement Selection using Linear Measuring
  

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To produce beef cattle that fits the consumer specifications and is profitable, requires very careful selection. Individual animals are evaluated for the transmission of desirable genetic traits such as gainability and ease of calving. We use the Redman Linear Measuring System and performance records to determine herd's strengths and weaknesses so that we can accurately set production targets.

All of our replacement heifers and bulls have been selected using the Redman Linear Measurement System. The system utilizes several measurements taken on the animal to help select animals for gainability, feed efficiency, fertility and muscling. The formulas used with these measurements have helped us improve our breeding stock and can benefit any program.

Some of the measurements used are:

Heart Girth: Highly correlated with weaning weight and yearling weight while lowly correlated with birth weight. Larger heart girth results in increased vigor, adaptability, and feed efficiency. Insufficient heart girth allows front feet to toe out and the animal will be a high maintenance animal and is more susceptible to stress. Each extra inch of girth gives an extra 37 pounds of red meat. A bull's heart girth should be equal to or larger than the topline length at twelve months of age.

Topline Length: A well-balanced animal will be 1/3 neck, 1/3 back and 1/3 rump. A bull with early hormone development should have a neck with a large hump resulting in a neck that is at least two inches short of 1/3 body length at twelve months of age.

Neck Length: Masculinity indicator. The shorter the neck, the higher the masculinity in a bull. Bulls with two inches or shorter neck length at twelve months have daughters that mature early. As the neck gets shorter a bull's daughters’ rump width gets wider producing more pounds of beef.

Rump Width: Rump width is an indicator of muscling and ease of fleshing. Bulls with wider rump widths are heavier muscled individuals, are easy keepers and mature earlier. Rump width also provides space for a larger loin and eye.

Shoulder Width: Shoulder width is a high indicator of masculinity and reproductive efficiency. Wider is better. A bull’s shoulders should be a minimum of two inches wider than his rump length. Bulls that meet this criteria will produce daughters that calve early, breed back and are capable of weaning a heavy calf. Bulls with wide shoulders have the ability to withstand stress and will produce calves with more uniform birth weights and weaning weights.

Scrotal Circumference: Masculinity indicator. The larger the better. The testicle size has a much greater significance at yearling than at maturity. Larger testicles indicate earlier maturing bulls. Measured in centimeters. Scrotal circumference is highly heritable and has a high positive genetic correlation to age of puberty of the bull's daughters. Studies have shown that for each additional 4.0 cm of scrotal circumference above the breed or herd average, one can expect a 1.0 cm increase in the scrotal circumference of male offspring and 15 days earlier puberty in female offspring.

All linear measurements are adjusted to 365 days of age.


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