The common, but not universal minhag in Eretz Yisroel is that the meal served in honor of a bris is fleishik, whereas, in the United States, the meal served is often milchik, which minhag is correct?
The Magen Avraham (249:6, citing Rav Shlomah, rebbi of the Shelah Hakadosh) rules that a se’udas bris is fulfilled specifically with a meat meal. This view, which is based on the principle that “there is no joy other than in meat and wine,” is also stated by Rav Yaakov Emden in his siddur and is noted by several other authorities (see Shulchan HaEzer Vol. 2, p. 88b; Chavas Ya’ir 70; Shu”t Shevet Mishimon, Beis Mishteh 15; among others).
These authorities maintain that a person will not fulfill the obligation of a mitzvah meal with a dairy meal, and in fact many contend that a fowl meal is also insufficient, and the mitzvah requires specifically a meat meal (see Mor U’Ketziah, Siman 696, who writes that the joy of meat cannot be achieved with fowl; Leket Yosher, p. 157, also writes that the joy of meat does not apply to fowl).
However, other authorities disagree. Specifically, the Olas Shabbos and Chemed Moshe (mentioned by the MaChatzis HaShekel, siman 249) permit even a dairy meal for a bris.
Today it is the custom to rely on chicken rather than actual meat. Due to the fact that a bris is often held in the morning hours, when some find it difficult to eat meat, the custom of a dairy seudah has also grown in popularity, and Rav Elyashiv zt”l is cited as permitting it. Therefore, although ideally one should host a meaty seudah, it’s ok to host a milky one.
A number of Teshuvos have been written on the topic, and a number of fascinating reasons have been offered for why the minhag changed, and it has become very standard to host a milky seudah. See for example, Shu”t Mishneh Halachos (13:187), Toras Chaim (249), Zocher HaBris (25:7), and Teshuvos V’Hanhagos (2:485, and 3:294).
