In the spring of 1990, half-blood Red Angus Gelbvieh cross bulls were purchased and put on purebred Hereford cows.

The resulting progeny, ½ Hereford, ¼ Red Angus, and ¼ Gelbvieh were then bred to Red Brangus bulls, forming the RedBell composite.

Since Red Brangus is a composite of 5/8 Red Angus and 3/8 Brahman, the RedBell is approximately 7/16 Red Angus, 4/16 Hereford, 3/16 Brahman, and 2/16 Gelbvieh. Over the past few years, we have played with the percentages somewhat through designed matings and have increased the Gelbvieh component to around 25% and reduced the Brahman blood to about 10%.

No females have ever been brought in since the program's inception. No bulls have been purchased for the seedstock division since 2000, so as attrition removes the earlier purchased bulls, the likelihood is that the seedstock herd will be closed to outside genetics. One of the goals of RedBell development was to establish a breed of cattle adapted to our environment, able to withstand the year-to-year variation in precipitation and feed availability. We do not feel like we can do this by continuing to bring in genetics from diverse environments. As the ranch bulls complete their progeny test in the commercial division for growth, carcass and reproductive traits the superior sires will be returned to the seedstock division by the time they are four years old to become herd sires.

One of the Mule Camp seedstock herd sires, Double Tender, has tested homozygous for the tenderness marker. For 2004 Double Tender and his sons were turned out at the begining of the breeding season alone to increase the frequency of these genes in the herd. Also in 2004 the genotyped commercial replacement heifers were AI'd to black Angus bulls with favorable alleles for tenderness for marketing purposes.

The data on birth weight, weaning weight and yearling weight of the composite cattle and the purebred Hereford cattle are presented below. The data are inclusive of Herefords calves born from 1980-1992 and composite calves born 1991-2001. The Comp-Int calves are ½ Hereford, ¼ Red Angus, ¼ Gelbvieh.

The amount of heterosis, given by the MARC formula, retained in the RedBell is about 70%. The expected weaning weight heterosis in an F1 is 23%, so multiplying 23% by 70% gives an expectation of weaning weight heterosis in the Redbell of 16%, or exactly what we have experienced.

On the other side of the coin, however, are mature cow weights. In an attempt to moderate cow size, we weigh each cow individually at pregnancy diagnosis. Analysis of these data show that mature cow size is increasing, but the weights of first- and second-calf heifers are not. The following table gives the trends in cow weights by ages over time.

Continued observation of cow weight will be necessary to ensure they do not outgrow the environment.