Hold on there SPCA police squad? Your looking at a pix an your tar and feathering me? I'd encourage you to read up on the Jack Russell Terrier!
One of the traits with this "fearless" little bred is "they" incite and dare rough play! They have unlimited energy! Unless you do also this would not be a good breed for YOU!
Another is they are so "agile" you can bend them in half, touching nose to tail!
So before opening mouth, and inserting foot, with your accusations of cruelty upon a breed that you "obviously" know little about,,,,, stfu!
David