The gemara in Sanhedrin 5a teaches us about 3 different levels of semicha:
“Yoreh Yoreh”- primarily in Yoreh Deah, but can also include Shabbos, Niddah etc- which allows the person to issue rulings in ritual law.
“Yadin Yadin”- inyanei Choshen Mishpat- but can also include Even Haezer- which gives the person the authority to rule in cases of monetary law.
“Yatir Bechorot Yatir”- As explained by R' Ari Enkin from TorahMusings:
“Yatir Bechorot Yatir” semicha, which conferred upon the recipient the authority to determine matters relating to animal sacrifices. This included approving or disqualifying animals for ritual and sacrificial purposes based on the animal’s physical health or any blemishes that it might have. In many cases, a blemished animal was unfit to be offered in the Beit Hamikdash or to be used for other ritual matters. In addition to the halachic proficiency that the recipient was required to have regarding Temple and sacrificial proceedings, the recipient also underwent extensive veterinary training, as well.
While these guidelines illustrate that “Yatir Bechorot Yatir” semicha is DEFINITELY not easy to obtain, I'm sure a very select few in the world know Hilchos Kodshim cold, and could also probably shimush to learn more about animals.
Why doesn't “Yatir Bechorot Yatir” semicha exist nowadays?