All of the missions had extensive livestock herds. San Juan Capistrano had large numbers of cattle (ranging between 10,000 - 14,000 head during their peak years of 1806-1827) and an average of about 12,000 sheep during the same years. Their annual reports show some goats (203 in 1820), pigs (195 in the same year) and of courses horses (about 140 on average), which we used for transportation. While San Juan Capistrano didn't have the largest herds of livestock in the mission chain, it was in the upper half.
Mission Animals and Livestock / Mission Brands
The first thing that needs to be said is that the circle in this brand belongs at the top, as shown below. This brand is sometimes shown with the circle at the bottom, which is wrong.
They were beef (not dairy) cattle. We do not have information on the breeds that were imported, but will research this and let you know if we find out more information.
I have checked with a couple mission scholars to see what they can tell us. The consensus seems to be the missions and settlers probably did introduce both animals. Cats were used on Spanish ships to control rats. For much of the Spanish era, ships from San Blas (on the Baja peninsula) brought supplies and missionaries to California and a few wily cats may have escaped or been taken as pets. There is a story about one of the missionaries (Fr. Uria) who had a collection of cats. Dogs were used to control sheep on the mission lands. All of the missions had large livestock herds.