Yosef Karo

“ The vessels of the neck are not of these, rather you must cut the entire spine in two.
3 The wing bone is like the limb of a beast, and therefore it is necessary to cut the wing bones and salt them. Similarly, the jawbone of a bird:
Note: Some say that there is no need to take these tendons from birds because they are thin and the blood comes out of them through salting (Ran, Chapter of the Slaughterer) . And the custom is not to take any tendons from birds except for the neck tendons, and in those cases one should be careful to take them from there or cut them with the joint into two. ”

“ However, nevertheless, we do not purchase meat from any butcher who slaughters for himself and sells to himself unless he is trusted in his kashrut.
סעיף א יש חוטין שאסורים משום דם שבהם, כגון חוטין שביד, ושבכתף, ושבלחי התחתון שבצד הלשון מכאן ומכאן, ובלשון, ובצוואר, וחוטי הלב, וחוטי העוקץ, וחוטי הדקין שהם בתוך שומן הדקין כמו בית עכביש מסובכין זה בזה, הגה: ונוהגין להסיר גם כן ג' חוטי אורך אצל החזה מבפנים (א"ו הארוך) , וכן נוטלין חוטין אחורי האזניים (סדר הנקור וארוך) ואינו אלא חומרא בעלמא (ד"ע) וקרום שעל המוח שבקדקד וקרום שעל הביצים. ”

“ All that has been said is only for cooking in a pot, but for grilling: it is not necessary to either cut (the vessels) or salt (the meat) because the flame will surely draw out (the blood) . There are those who say that this is only if the vessels are immediately facing the face of the fire, but if they are absorbed (covered) by the flesh the fire will not be effective with out first cutting the vessels. If they are not removed, and the are cooked with out cutting- there must be 60 for every one of the vessels. But with grilling, it is enough to simply peel them i.e. ”