Translation:I want three cats.
When looking up the kanji for the counter of cats (small animals), I noticed the reading was ひき instead of the びき used in this example. So for those who are wondering why its 「三びき」instead of 「三ひき」check this page. Basically:
When counting small animals, all of the numbers end in -hiki except the number 3 (which ends in -biki) and the numbers 1, 6, 8, and 10 (which end in -piki).