When breeding percentage Lowlines, you get exactly what you get.... when you do the math digitally or in fractions. ... a purebred bull (7/8's or 87.5 %) will give you a 43.75% calf out of a commercial cow. It would be a 46.875% (46.88% rounded to two places) if a 15/16's (93.75%) bull was bred to a commercial cow.
A fullblood Lowline bull when mated to a commercial cow will always give you a 50% or halfblood calf which is the minimum percentage eligible to show in any of our currently ALR sanctioned shows.
An animal must be a minimum of 1/4 (25%) Lowline to be registered in the ALR herdbook. A 1/4 (25%) female when mated to a 3/4 (75%) bull will produce a halfblood calf.
To answer the inevitable question of what good is a purebred then .... a purebred bull bred to a purebred female always gets you a purebred calf... never anything less but by the same token a purebred is always a minimum of 87.5% percent Lowline now matter how many generations it takes you to get there.
Obviously the fastest way to get to a purebred in only three crosses is by always using a fullblood bull which, unlike some other breeds, keeps the value in the Lowline fullbloods, a very important and critical distinction in our breed.
A breeder may choose, once at the purebred level, to simply stay there by using purebred bulls instead of fullbloods. This leaves lots of opportunities when considering opening up the gene base contributed by the other base breed for other selection criteria like red factor, black whiteface, belted Lowlines as well as carcass and performance genes that may be available from breeds like Wagyu, Simmental, Charolais, Red Angus, Salers, Devon, Scotch Highland and Belted Galloway or heat tolerance traits like the bos indicus cattle can contribute.
I plan to use my 9/16's (56.75%) bull on some of my 15/16 (93.75%) (purebred) females to come back to a 3/4 calf which is the minimum percentage required to show in the Texas Junior Livestock Association sponsored shows. The carcasses of 3/4 steers are in great demand by our beef customers. This is also an example of how you can use Lowline genetics to optimize your efficiency by making a relatively small, low maintenance cost cow be all she can be and wean in excess of 50% of her body weight each year by breeding her to a bigger framed, higher performance, lower percentage bull.
Within our current ALR system the options are endless! We want each breeder to raise the kind of cattle they like and can make work in their market and on their ranch.