Does anyone know why you don't see white dog poo anymore? When we were kids there was tonnes of it, now its rarer than hen's teeth. Is it something to do with diet?
Yes...diet. It was associated with the fact that dogs in the past were often given bones, which they would gnaw endlessly. (This rarely happens nowadays.) As a consequence, they ingested lots of calcium and that resulted in the chalky appearance of their poo. In the 1940s/1950s, children actually used the stuff as if it was chalk to mark out hopscotch diagrams etc on the pavements!
I can remember in the early 70's, picking up 'chalk' and wondering why it didn't last very long on the pavement! Thankfully, it didn't smell and we didn't eat it, so it didn't do us any harm - we always washed our hands as soon as we went indoors anyway!
I think its also a lot to do with the fact that its now an offence to let your dog foul the pavement. There was loads of the stuff, white or otherwise when I was a kid, but its not very uncommon.