Males are 45 - 50 cm (18 - 20 inches) in height at the withers, while females are 42 - 47 cm (17 - 19 inches). The body is not square, but rectangular; the ratio of the height to the body length should be 9:10 (a 45 cm tall dog should have a body 50 cm long). The tail is either very short or docked. Some undocked dogs have tails that curl over the back.
Kazimierz Grabski, a Polish merchant, traded a shipment of grain for sheep in Scotland in 1514, and brought six PONs to move the sheep. A Scottish shepherd was so impressed with the herding ability of the dogs that he traded a ram and two ewes for a dog and two bitches. These dogs were bred with the local Scottish dogs to produce the Scottish herding dogs, most obviously the Bearded Collie.
Almost driven to extinction in World War II, the PON was restored mainly through the work of Dr. Danuta Hryeniewicz and her dog, Smok (en:Dragon), the ancestor of all PONs in the world today, who sired the first ten litters of PONs in the 1950s. The breed standard was written with Smok as the model, and accepted by the Fédération Cynologique Internationale in 1959.
In general, PONs are a very healthy breed. Animals should be checked for hip dysplasia and progressive retinal atrophy before being used for breeding. PONs require a low protein diet. The life expectancy of a PON is 12 to 15 years.
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