Meilah 12B

דאמר רב: המקיז דם לבהמת קדשים, אסור בהנאה, ומועלין בו.

As Rav said: In a case of one who lets blood from a live sacrificial animal, deriving benefit from that blood is prohibited and one is liable for misusing it by Torah law. Since there is a stage when there is a prohibition of misuse by Torah law, one can understand the halakha that one is liable by rabbinic law for misusing the blood ultimately, when it descended to the Kidron Valley. This is not comparable to doves whose time of fitness for sacrifice has not arrived, as they are initially not subject to misuse by Torah law.

גופא. אמר רב הונא, אמר רב: המקיז דם לבהמת קדשים ⁠– אסור בהנאה, ומועלין בו. מתיב רב המנונא חלב המוקדשין, וביצי תורין ⁠– לא נהנין ולא מועלין!

§ The Talmud analyzes the matter itself. Rav Huna says that Rav says: In a case of one who lets blood from a sacrificial animal, deriving benefit from that blood is prohibited and one is liable for misusing it. Rav Hamnuna raises an objection to the opinion of Rav from the Mishnah below: With regard to the milk of animals consecrated to be sacrificed and the eggs of doves consecrated to be sacrificed, one may not derive benefit from them ab initio, but if one derived benefit from them he is not liable for their misuse, despite the fact that one is liable for misuse of the animals and doves themselves. Apparently, the products of a consecrated item do not share its status with regard to the halakha of misuse. Why doesn’t this principle apply to blood as well?

אמר ליה: כי קאמרינן, לגבי דם, דלא מתקיימת בלא דם. אבל חלב, דקא מקיימא בלא חלב ⁠– לא.

Rav said to Rav Hamnuna in response: When we said the products of a consecrated item are also subject to the halakha of misuse that was only with regard to blood, as the animal cannot exist without blood and therefore the blood is considered like the animal itself. But in the case of milk, since the animal can exist without milk, the milk is not considered like the animal itself.