Midrash su Levitico 27:32

1) "all that shall pass under the staff": to exclude a treifah (an animal with an organic defect), which does not pass. This tells me only of his counting them with the staff. If he did not count them with the staff, or if he counted them lying down or standing, whence do I derive (that it is valid)? From "shall be holy" (in any event). This tells me only of his calling it "the tenth." Whence do I derive (that it is valid) even if he did not call it "the tenth"? From "the tenth shall be holy." I might think that even if he had one hundred and took ten (at random), or ten and took one (that it is valid); it is, therefore, written "the tenth," and this is not ma'aser (lit., the tenth). R. Yossi b. R. Yehudah says: It is ma'aser.

2) Whence is it derived that if he (erroneously) called the ninth the tenth; the tenth, the ninth; and the eleventh, the tenth, that all three are considered (as ma'aser)? From "the tenth shall be holy to the L–rd." I might think to include the eighth and the twelfth (that he called the tenth). Would you? No. Since it is consecrated and its "error" is consecrated, just as only what is closest to it (i.e., it itself) is consecrated, so only the "error" closest to it (i.e., the ninth and the eleventh) is consecrated (and not the eighth and the twelfth).

3) "an ox or a sheep": to exclude a hybrid. "or a goat": to exclude a nidmeh (a sheep which looks like a goat, or vice-versa). When it is born": to exclude one delivered by Caesarian section. "and it shall be seven days": to exclude (acceptability) before that time. "under its mother": to exclude an orphaned animal. R. Yishmael b. R. Yochanan Beroka says: It is written here "under," and elsewhere (in respect to tithes, Vayikra 27:32) "under (the staff"). Just as "under" here excludes a hybrid, a Caesarian, before its time, and an orphan, so, "under" there. And just as "under" there excludes a treifah, so, "under" here.