There are a two things here, using language, such as saying "davar acher" instead of the name of the animal, which traces back to the 5 books of Moses, (einenu tehorah) and showing pictures of those animals to kids. Both of these the Rebbe spoke about, and I'll try post links when I get some time, bl"n.
The Rebbe's use of positive language was way more hmm just for non-kosher animals. Telushkin wrote about it in his biography, perhaps someone can post images.