Tosefta zu Kelim 1:16

There is a stringency with corpse-impurity that there is not with a ba'al niddah (one who has intercourse with a menstruant), and [there is a stringency] with a ba'al niddah that there is not with corpse-impurity. That [one contaminated by] corpse-impurity requires sprinkling on the third day and the seventh day, which is not the case with a ba'al niddah. The stringency with a ba'al niddah is that a ba'al niddah defiles the bottom [bedding] just as the top bedding, which is not the case with corpse-impurity. Rabbi Yosei says, the emission of a zav, his spit, his semen, and his urine, [and the blood of a niddah (per GR"A)], and a revi'it of blood of a corpse [also defile both the top and bottom bedding]. Why did they say a "revi'it"? Because anyone who crosses the threshold of creation has [at least] a revi'it of blood. And regarding the blood of a niddah and [contamination with] riding-uncleanliness (Lev. 15:9, see Jastrow ("מרכב")), there is a stringency with [a niddah] that there is not with riding-uncleanliness, and with riding-uncleanliness that there is not with [a niddah]. That [the niddah] is equivalent to one who renders a person impure or clothing impure by contact or by carrying, which is not the case with riding-uncleanliness (Kel. 1:3). The stringency with riding-uncleanliness is that one who possesses riding-uncleanliness can impart impurity [even] under a heavy stone, which is not the case with [a niddah].

Abba Shaul says, the upper chamber of the Holy of Holies is more stringent than the Holy of Holies [itself], for [with regards to] the Holy of Holies, the High Priest enters into it each and every year for the Yom Kippur service, four times on [that] day, and if he enters a fifth time he is liable for the death penalty, but [with regards to] the upper chamber of the Holy of Holies, they may not enter it but once in seven years (following the GR"A), to determine what is needed. They said to him, "That does not make it of higher [sanctity]." [If] metzorayim (i.e., lepers) entered within the wall [of Jerusalem], they are administered forty [lashes]. Zavim and zavot, niddot, and women after childbirth, [who enter] the Temple Mount are administered eighty [lashes] (Kelim 1:8). One who is impure may enter the Temple Mount, but not one with corpse-impurity. [But] the Sages say, rather, even a corpse itself [may enter the Temple Mount], as it is said (Ex. 13:19), "And Moses took the bones of Joseph with him." "With him" -- into the Camp of the Levites (the functional equivalent of the Temple Mount in the desert). Rabbi Shimon says, [with respect to] the Rampart and the Women's Courtyard in the Temple (lit., "the Eternal House"), the impure people who entered there were exempt.

And these are the tereifot (=טרפות, "mortal injuries or defects," lit. "torn flesh" (see Ex. 22:30)): A perforated gullet, a windpipe severed widthwise, behold this is disqualified. Rabbi Shimon ben Elazar says, in addition, [an animal] whose nerve tissue was "emptied" [from the spinal cord (Hul. 45b:17)] is disqualified. [An animal that had] a broken spine and a majority of its [spinal] cord was cut is disqualified. [An animal with] a withered lung, or if it no spinal cord is present, is disqualified. Rabbi Ya'akov says, even if it is perforated. If the liver is removed and there does not remain in it [a sufficient quantity of flesh] to allow a scab to form ("כדי להעלות ארוכה," see Kel. 1:5), it is disqualified. [An animal whose] inner stomach is perforated, or where the majority of the outer stomach is torn [is disqualified]. Rabbi Yehudah says, [a tear the size of] one handbreadth in a large [animal], and in a smaller [animal] if most of it [was torn], it is disqualified. And how large [must the stomach be for an animal to be deemed "large"]? Two handbreadths, behold, that is large. Less than that, behold, it is [a] small [animal]. What is the "inner stomach"? Ben Sheila, Head of the Seventy ("ראש שבעים," alt., "ראש טבחים" = "head butcher," see Minchat Yitzchak) testified in Tzippori in the name of Rabbi Nathan: It is the cecum (Hul. 50b:2).