Menachot 80 – Accidental Thanksgiving

A thanksgiving offering can be either a male or a female animal. If the female thanksgiving animal gave birth, its offspring is automatically sanctified as another thanksgiving, like its mother. However, unlike its mother, it does not require the forty breads to come with it.

Similarly, if one says “let this animal be a substitute for this thanksgiving offering,” he has done something that is not right – for substitutes are prohibited – but his words take effect, and now both animals are thanksgiving offerings; however, the second one is brought without the breads. This rule is also true when his thanksgiving offering was lost, he designated another one instead, and then the first one was found.

Why this rule? – The Torah said, “Then he shall offer with the thanksgiving offering matzah loaves...” to teach us that only the thanksgiving offering requires loaves, but neither its offspring, its replacement, or its substitute require loaves.

John Frederick Herring Snr - A Cow And Calf In A Stall