History highlights pedigree ‘faults’
By DAVID BRASCH
HOW many times have you heard a broodbitch owner with a sprinting bitch reckon he needs to mate her to a ‘strong’ sire in a bid to get 500m performers?
Or conversely, how many times do the same breeders have a staying bitch they will look to mate with a speedy squid to get 500m performers?
Few, if any will get what they are chasing.
A bloke called Gregor Mendel found out the answer to those breeders’ problems and he did it way back in the 1860s.
The way in which traits are passed from one generation to the next, and sometimes skip generations, was first explained by Mendel. By experimenting with pea plant breeding, Mendel developed three principles of inheritance that described the transmission of genetic traits, before anyone knew genes existed.
Mendel’s insight greatly expanded the understanding of traits passed down in families in different patterns.
Pedigrees can illustrate these patterns by following the history of specific characteristics as they appear in a family.
Mendel was curious about how traits were transferred from one generation to the next, so he set out to understand the principles of heredity. Peas were a good model system.
Before Mendel’s experiments, most believed traits in offspring resulted from a blending of the traits of each parent (sound familiar to greyhound breeders). However, when Mendel cross-pollinated one variety of purebred plant with another, these crosses would yield offspring that looked like either one of the parent plants, not a blend of the two.
Queensland dog man, Doug Gladman, and his wife Heather, have been taking all before them of late on the racetrack with a speedy bitch called Tyanna Belle, winner of the recent Thunder at Albion Park.
Doug has been a ‘genetics man’ for most of his life and spent many years teaching genetics with the Department of Agriculture in NSW.
He was even called to NZ by Glyn Tucker, then Keeper of the thoroughbred Stud Book, for a two-week tour of the country talking genetics and colour inheritance etc way back in the 1970s.
“Glyn needed help because one of New Zealand’s leading breeders was trying to register a colt that his colour showed could not have been of the parentage it was claimed,” said Doug.
“Today with DNA, the problem would have been solved instantly.”
Tucker needed Doug’s colour inheritance expertise to back his findings on the colt and help with the tour involving NZ breeders.
“Mendel’s Theory about dominant and recessive genes is something greyhound breeders should take notice of,” said Doug.
“I spent my early racing life in thoroughbreds and did a lot of research in that field. It fascinated me and I did a bit of research.”
Some of that research revolved around a grey stallion called Royal Yacht who was dominant for his own colour. “Grey is a disease of the coat but Royal Yacht had no other gene in him for anything but the grey coat,” said Doug.
His recent study of coat colour dominance in greyhounds has tossed up dogs like Lochinvar Marlow whose only progeny are black.
“That’s what Mendel was all about,” said Doug.
“Behind all this is Mendel’s Theory and it explains why putting a stayer to a sprinter will not necessarily get a middle of the range performer,” said Doug.
“It just doesn’t happen.”
Doug’s time in the thoroughbred industry left him with some fascinating insights.
“The Two Ts,” said Doug. “Todman and Tulloch were the greatest racehorses of their time and dominated racing to a degree they have long been regarded as legends.
“But what was most fascinating to me was that both went to stud and had completely different impacts.
“Todman was a great success as a sire, Tulloch was an abject failure. What was the difference in them?
“Both were greats on the track, but Todman went to stud with a fabulous pedigree, Tulloch was a freak.
“One was bred to be a champion, WAS a champion and left champions. The other was a freak and threw nothing.”
It is also why some great race dogs will become champion sires, others will not.
“Each dog contains 39 chromosomes and there needs to be lots of principal factors in the dog’s make-up to see success at stud,” said Doug. “He needs to be able to pass on endurance, speed etc all those genes that make him a dominant sire.
“And he must not have recessive genes.”