Tractate Bekhorot - Chapter 2 - Mishnah 3

All [consecrated animals] whose consecration preceded their permanent, or their impermanent blemish [preceded] their consecration and subsequently they contracted a permanent blemish, and they were redeemed:Are exempt from the law of the firstling, and from priestly gifts; And they are not like unconsecrated animals to be shorn or put to work; And [even] after they have been redeemed their young and their milk are forbidden; And he who slaughtered them outside the sanctuary is liable; And they render what was substituted for them [holy], And if they died they must be buried.