buey.

yhua bacas chiCuase yhua se se yota bues = 6 cows, a yoke of oxen (Toluca Valley, 1737)
Caterina Pizzigoni, ed., Testaments of Toluca (Stanford: Stanford University Press and UCLA Latin American Center Publications, 2007), 124.

Nitlanahuatia ome yunta bueyes Ca yehuatl nicCahuilia noçiuh se Caballo ençillado yuã Caxa ome achas yuã mochi Santoz Santaz çe CuetzComtal nicCahuilia noxpochto Juana = I order that I leave to my wife two yokes of oxen, a horse with a saddle, a chest, two axes, and all the male and female saints; I leave a corncrib to my little daughter Juana. (San Pablo Tepemaxalco, Toluca Valley, 1695)
Caterina Pizzigoni, ed., Testaments of Toluca (Stanford: Stanford University Press and UCLA Latin American Center Publications, 2007), 146.

omen yonta buyenyen = two yokes of oxen (San Pablo Tepemaxalco, Toluca Valley, 1681)
Caterina Pizzigoni, ed., Testaments of Toluca (Stanford: Stanford University Press and UCLA Latin American Center Publications, 2007), 150.

se yota boeyes yhuan ome rexas conanas macos = una yunta de bueyes y dos rejas, que las coja, que se le den. (San Marcos Tlayacac, Morelos, "1546"; no earlier than 1666)
Vidas y bienes olvidados: Testamentos indígenas novohispanos, vol. 2, Testamentos en náhuatl y castellano del siglo XVI, eds., Teresa Rojas Rabiela, Elsa Leticia Rea López, Constantino Medina Lima (Mexico: Consejo Nacional de Ciencias Tecnología, 1999), 80–81.