Changes in pars esophageal tissue appearance of the porcine stomach in response to transportation, feed deprivation, and diet composition.

Experiment 1 used 48 pigs to evaluate the effect of diet particle size, fat content, and a 24-h fast (FST) on pars esophageal (PE) tissue damage. Following a FST, a 750-microm, 550-microm, or 550-microm diet with 7.9% added fat was fed for 28 d. Additional pigs were fed the 550-microm fat-added diet with a FST every 7 d. The initial FST induced erosion (EROS) of the PE (P < .05). A 550-microm diet maintained the FST-induced EROS (P < .05). The 750-microm diet allowed the PE to heal. Sixteen pigs were used in Exp. 2 to evaluate transportation and FST-induced changes in PE. A FST following transportation induced keratinization (KERT) and EROS of the PE (P < .05). In Exp. 3, restraint and a FST followed by a 750-microm diet on PE was investigated using 48 pigs. A FST induced PE KERT and EROS, which was reduced to pre-FST levels ( P < .05) within 3 to 14 d by a 750-microm diet. In Exp. 4, 70 pigs were fed 750-microm or 550-microm diets following transportation and subsequent FST. Within 7 d, healing (P < .05) of FST-induced PE damage was observed with a 750-microm diet. A 550-microm diet maintained (P < .05) the transportation/FST-induced PE damage. Thirty pigs were used in Exp. 5 to investigate the effect of restraint for 24 h and FST on PE. A FST and the combination of restraint and FST induced similar levels of PE damage that were greater than pre-restraint/FST levels (P < .05).