I heard this suggestion several years ago from a clever colleague. I haven’t heard it since but I bet he’s right – although it’s a bit late in the day now.
Is there any genetic basis for immunity to bovine TB in cattle? If so, why aren’t we using the more immune breeds of cattle? Is there any chance that ancient breeds have greater immunity than the strains of Holstein-Friesians that have been selected so strictly for their milk-producing capacity that they may have had bTB resistance bred out of them?
And even with the black-and-white beasts, is there genetic variation in susceptibity? I bet there is?
Has breeding for milk production above everything else been an own goal for the dairy industry? And similar arguments apply to beef cattle.
Just a thought.