A rhino/rhinoceros
a rhino
ibex, a type of antelope.
Water buffalo.
The kudu is an antelope. It is a deer like animal with curled horns.
Yellow-backed Duiker is an antelope found in Africa. It has 4 legs and horns.
Yak
The Gnu. They are also known as Wildebeest.
One example of alliteration that starts with "y" and includes an animal is "yawning yellow yaks." This phrase uses the repetition of the "y" sound to create a rhythmic and catchy expression featuring the animal yak.
yabbi
Yourr momm:P
Yellow fin tuna
There are quite a few ways to preserve animal horns. There are certain preservatives sold for this purpose of preserving animal horns.