יורה דעה ס׳Yoreh De'ah 60

Se’if 1א׳

אֲחוּזַת דָּם וְהַמְעֻשֶּׁנֶת וְהַמְצֻנֶּנֶת, אוֹ שֶׁאָכְלָה סַם הַמָּוֶת שֶׁהוֹרֵג הַבְּהֵמָה, אוֹ שֶׁשָּׁתְתָה מַיִם הָרָעִים, הֲרֵי זוֹ מֻתֶּרֶת. הַגָּה: בְּהֵמָה שֶׁנִּתְפַּטְּמָה בִּדְבָרִים אֲסוּרִים, מֻתֶּרֶת (מָרְדְּכַי דִּיבָמוֹת פ' אַלְמָנָה לכ"ג) אֲבָל אִם לֹא נִתְפַּטְּמָה כָּל יָמֶיהָ רַק בִּדְבָרִים אֲסוּרִים, אֲסוּרָה (תּוֹסָפוֹת דִּתְמוּרָה פ' כָּל הָאֲסוּרִים).

One seized with blood (achuzat ha-dam — a beast made ill by a congestion of blood), and one that was smoked, and one that was chilled, or one that ate a deadly poison that kills an animal, or that drank the evil waters — this is permitted. Hagah [Rema]: An animal that was fattened with forbidden things is permitted (Mordechai on Yevamot, chapter "A widow to a High Priest"); but if it was not fattened all its days save with forbidden things, it is forbidden (Tosafot on Temurah, chapter "All that are forbidden").

Se’if 2ב׳

אָכְלָה סַם הַמָּוֶת שֶׁל אָדָם, אוֹ הִכִּישָׁהּ נָחָשׁ וְכַיּוֹצֵא בּוֹ, מֻתֶּרֶת מִשּׁוּם טְרֵפָה וַאֲסוּרָה מִשּׁוּם סַכָּנַת נְפָשׁוֹת.

If it ate a deadly poison that kills a man, or a snake bit it or the like, it is permitted as regards tereifah (an animal with a fatal defect) but forbidden on account of the danger to life.

Se’if 3ג׳

בְּהֵמָה אוֹ חַיָּה שֶׁנִּפְסְקוּ רַגְלֶיהָ, לֹא יֹאכְלוּ מִמֶּנָּהּ אֶלָּא עַל יְדֵי בְּדִיקָה, שֶׁיֵּשׁ לָחוּשׁ שֶׁמָּא נְשָׁכָהּ נָחָשׁ. וְזוֹ בְּדִיקָתָהּ, שֶּׁלֹּא יֹאכְלוּהָ אֶלָּא צָלִי, וְאִם הִיא נְשׁוּכַת נָחָשׁ תִּתְפָּרֵק וְתִפֹּל חֲתִיכוֹת חֲתִיכוֹת. הַגָּה: וּלְדִידָן דְּלָא חַיְשִׁינָן לְגִלּוּי (מַיִם) הוֹאִיל וְאֵין נְחָשִׁים מְצוּיִין, לָכֵן אֵין לָחוּשׁ לְנָחָשׁ, וְאִם הוּא בְּדֶרֶךְ שֶׁלֹּא נֶעֶשְׂתָה טְרֵפָה, מֻּתָּר בְּלֹא בְּדִיקָה (בֵּית יוֹסֵף בְּשֵׁם רַבֵּינוּ יְרוּחָם וְכֵן כָּתַב א"ו הָאָרֹךְ).

An animal or a wild animal whose legs were severed — they shall not eat of it save by means of an examination, for there is ground to be concerned lest a snake bit it. And this is its examination: that they eat it only roasted; and if it is snake-bitten it will fall apart and drop in pieces upon pieces. Hagah [Rema]: And for us, who are not concerned for what has been left uncovered (water), since snakes are not common, there is therefore no ground to be concerned for a snake; and if it is in a manner in which it did not become a tereifah, it is permitted without an examination (Beit Yosef in the name of Rabbeinu Yerucham, and so wrote the Issur v'Heter haAroch).