Rashi on Genesis
ויזבח יעקב זבח AND JACOB OFFERED A SACRIFICE — he slaughtered cattle for the feast
Sforno on Genesis
ויקרא לאחיו, of Lavan. There was no need to invite Lavan himself seeing he was like a father to Yaakov’s children.
Radak on Genesis
ויזבח, he prepared a festive meal so that they would eat together before taking leave of each other. This was in honour of the covenant just concluded.