Morphometric analyis of the esophagus-gastric transition in horse submitted to different feeding management and physical activities - Moraes, P. T. B; Silva, Luis Claudio Lopes Correia da; Bombonato, Pedro Primo; Hernandez-Blazquez, Francisco Javier; Lima, E. M. M; Benedicto, H. G (Simpósio de Microscopia no Cerrado, 2008)