The BORI edition of Mahabharata does not contain any references to meat in this context (however, see the second part of this answer).
tataH praveshanaM chakre tasyAM rAjA yudhiShThiraH |
ayutaM bhojayAmAsa brAhmaNAnAM narAdhipaH || 1||
ghRRitapAyasena madhunA bhakShyairmUlaphalaistathA |
ahataishchaiva vAsobhirmAlyairuchchAvachairapi || 2||
dadau tebhyaH sahasrANi gavAM pratyekashaH prabhuH |
puNyAhaghoShastatrAsIddivaspRRigiva bhArata || 3||
Thereupon King Yudhisthira made his entrance into the hall, and the lord of men fed ten thousand brahmins with rice boiled in sugared milk, clarified butter, delicious honey, roots and fruit, and gave them new clothes and many kinds of garlands. The king gave each of them a thousand cows, and the sounds of the Blessing of the Day seemed to touch heaven, O Bhārata.
However, the supplementary passages of the Mahabharata BORI edition mentions that a few manuscripts contain this verse -
भक्ष्यैर्मूलैः फलैश्चैव मांसैर्वाराहहारिणैः
Above seems to be reference to pork and meat of deer. There is also another verse below in these manuscripts which refers to meat -
मांसप्रकारैर्विविधैः खाद्यैश्चापि तथा नृप