Halakhah for Chullin 2:6
הַשּׁוֹחֵט אֶת הַמְסֻכֶּנֶת, רַבָּן שִׁמְעוֹן בֶּן גַּמְלִיאֵל אוֹמֵר, עַד שֶׁתְּפַרְכֵּס בַּיָּד וּבָרָגֶל. רַבִּי אֱלִיעֶזֶר אוֹמֵר, דַּיָּהּ אִם זִנְּקָה. אָמַר רַבִּי שִׁמְעוֹן, אַף הַשּׁוֹחֵט בַּלַּיְלָה וּלְמָחָר הִשְׁכִּים וּמָצָא כְתָלִים מְלֵאִים דָּם, כְּשֵׁרָה, שֶׁזִּנְּקָה, וּכְמִדַּת רַבִּי אֱלִיעֶזֶר. וַחֲכָמִים אוֹמְרִים, עַד שֶׁתְּפַרְכֵּס אוֹ בַיָּד אוֹ בָרֶגֶל אוֹ עַד שֶׁתְּכַשְׁכֵּשׁ בִּזְנָבָהּ, אֶחָד בְּהֵמָה דַקָּה וְאֶחָד בְּהֵמָה גַסָּה. בְּהֵמָה דַקָּה שֶׁפָּשְׁטָה יָדָהּ וְלֹא הֶחֱזִירָה, פְּסוּלָה, שֶׁאֵינָהּ אֶלָּא הוֹצָאַת נֶפֶשׁ בִּלְבָד. בַּמֶּה דְבָרִים אֲמוּרִים, שֶׁהָיְתָה בְחֶזְקַת מְסֻכֶּנֶת. אֲבָל אִם הָיְתָה בְחֶזְקַת בְּרִיאָה, אֲפִלּוּ אֵין בָּהּ אַחַד מִכָּל הַסִּימָנִים הַלָּלוּ, כְּשֵׁרָה:
If an animal is slaughtered when it is dangerously ill, according to Rabbon Simeon ben Gamaliel, "It is sufficient [to render it Cashér] when it can move or struggle with its fore and hind legs." R. Eleazar saith, "It suffices if the blood spirted after its throat was cut." R. Simeon teaches, "That even when a person slaughtered such an animal at night, and found in the morning the walls [of the slaughter-house] covered with blood, it is Cashér, agreeable to R. Eleazar's opinion." But the sages hold it to be Cashér only, "when the animal struggled with either his fore or hind leg, or that it wagged its tail;" this applies to small as well as to large cattle. When a small cattle [a sheep or goat, &c.] is slaughtered [when dangerously ill], and extends its fore-leg, but does not draw it back, it is Pasool, because it only indicates the last throe of parting life. This is to be understood only in case the animal is supposed to be in imminent danger; but when it is considered sound, although it should not have exhibited any of the mentioned symptoms [after being killed], it is Cashér.