THE INFLUENCE OF A PURE-BRED BULL.

Otago Witness, Issue 3513, 12 July 1921, Page 11

THE INFLUENCE OF A PURE-BRED BULL.

Progress in Five Generations Using Purebred I > Li!i 3 and Native Cows. The differences produced in stock by usi: An American stock journal most graphically illustrates the difference produced upon a herd when a pure bred bull is used, as against when a grade or scrub sire is put on to tile cows. In word-painting and in line drawing, the story is told by our contemporary as follows: Tom Janes and John Brown live on adjoining farms. Each of them owns a scrub cow. l’he live stock improvement merchant (from “town”) gave them a bulletin on grading up by the use of better sires, and they have decided to try it. Joe Smith, who lives a mile down the xoad, owns a three-quarter grade Shorthorn bull. The neai’est pure-bred Shorthorn bull is a herd header on the Wanglem Farm seven miles a way. There isn’t a great deal of difference —on the outside —between a three-quarter blood and a pure-bred. Tom Jones, being busy, Eatronises Joe Smith’s three-quarters Shortorn bull. John Brown, remembering a copybook maxim that whatever is worth doing is worth doing well, takes the trouble and the time to patronise the pure-bred bull at the Wanglem Farm. There would not seem to be very much difference in the offspring. But, in actual fact, John Brown accomplishes in two crosses a result that is a little better than Tom Jones gets in five crosses. In about four years John Brown has ail animal of a fraction higher grade than Tom Jones can get in about 15 years. There may be no way to show it mathematically, but every reasonable man knows that the difference between four years and 15 years is greater than the difference between a mile and seven miles. The thing needs a little diagraming to make the differences stand out. Here is whart John Brown did by breeding his scrub cow to the pure-bred bull: 1 plus 0 equals 1;

THE PICTURE TELLS ITS OWN STORY.

(Progress in Five Generations Using Grade Bulls and Native Cows, ng Pure-bred Bulls as against Grade Bulls. divided by 2 equals 4- John Brown’s calf was half Shorthorn and half scrub. Here is what Tom Jones did by breeding his scrub cow to the three-quarter bull: % plus 0 equals f; divided by 2, equals §. Tom Jones’ calf was three-eights Shorthorn and live-eights scrub. Not much difference in the first generation but wait. Using those heifer calves as breeding stock, and mating them with the same kind of bulls, here is what happens : John Brown gets 1 plus g, which equals 14, divided by 2, equals 5Tom Jones get | plus §, equals 9-8; divided bj' 2, equals S-16. John Brown’s calf in the tion outgrades Tom Jones’ calf in tire second generation by § Shorthorn blood. And Tom Jones has to breed three other generations of cattle (using the same kind of sire) to bring his cattle up to approximately the same grade as John Brown’s second generation of offspring. In the meantime, using the same kind of bull, John Brown has graded his cattle up till the offspring of the original scrub cows contain 31-32 Shorthorn blood, and only j 1-32 scrub blood. Tom Jones’ cattle in the I same generation, contain 93-128 Shorthorn | blood and 35-128 scrub blood. Jones’ herd, after 15 years of work, still I retains 35 times as much scrub blood as j John Brown’s cattle—all because, 15 years | ago, John Brovin took the time and the ' trouble to travel seven miles instead of a mile. ; The cost of bulls varies greatly, of course, | according to quality of breeding, age, and j other factors. The moral of the story is obvious, it is to use pure-bred sires for herd improvement. Replace the scrub sires and the grade sires with good pure-breds.