In this May 1, 2016 photo, donkeys dressed as a lion and as Donald Trump touch noses as they await the start of the costume competition event at the annual donkey festival in Otumba, Mexico state, Mexico. Costume themes for the animals this year ranged from the ride-sharing Uber to pre-Hispanic temples. (Photo by Rebecca Blackwell/AP Photo)





In this May 1, 2016 photo, a reluctant donkey is alternately pushed and pulled and enticed with carrots toward town hall in order to be dressed for the costume competition at the annual donkey festival in Otumba, Mexico state, Mexico. Otumba was an important donkey market during Spanish colonial times, standing at the crossroads of major roads leading to Mexico City, where the beasts pulled heavy loads and carried travelers. Today, however, farmers use tractors and pickup trucks, and the donkey population is in decline. (Photo by Rebecca Blackwell/AP Photo)





In this May 1, 2016 photo, a man dresses a donkey to resemble Donald Trump in preparation for the costume competition at the annual donkey festival in Otumba, Mexico state, Mexico. The donkey was later adorned with a blond wig and eyebrows. None of the Trump entrants won much favor with the audience at the 51st annual donkey fest. Audience applause chose donkeys emulating a Smurf, a firefighter and an Uber ride for the first top three prizes. (Photo by Rebecca Blackwell/AP Photo)





In this May 1, 2016 photo, 12-year-old Wilfrido Lemus Corona races toward victory atop his donkey "Veso" in the final race at the annual donkey festival in Otumba, Mexico state, Mexico. Lemus learned to ride when his grandfather plopped him on top at age six to carry him across the fields, his mother Patricia Corona Espinosa said. Family and friends threw the tiny jockey into the air Sunday after he scored his third consecutive win. He also took home 12,000 pesos in cash, about $700. (Photo by Rebecca Blackwell/AP Photo)





In this May 1, 2016 photo, men wearing donkey ears and costumed as part of the security detail walk alongside a donkey and pig dressed as Donald Trump, during the costume competition at the annual donkey festival in Otumba, Mexico state, Mexico. Four families dressed their donkeys in likenesses of the U.S. presidential candidate who has vowed to build a border wall to keep out Mexican immigrants he's called “rapists”. The entrant featuring the costumed pig carried a sign declaring, “Impostor! I'm the real Donald Trump!” while another group's sign read “If I win the 12,000 peso prize, I'll put a wall between Otumba and Teotihuacan”, referring to the famed pre-Aztec city of pyramids nearby. (Photo by Rebecca Blackwell/AP Photo)





In this May 1, 2016 photo, a competitor falls from his donkey during a preliminary race at the annual donkey festival in Otumba, Mexico state, Mexico. The small town just north of Mexico City gives the beasts of burden a chance every May Day to kick up their hooves. (Photo by Rebecca Blackwell/AP Photo)





In this May 1, 2016 photo, spectators are covered with foam that was sprayed by a team competing in the costume event, at the annual donkey fair in Otumba, Mexico state, Mexico. The annual donkey fair in Otumba attracts up to 40,000 people who come to see the animals compete in costumes and race around a track with jockeys on their backs. (Photo by Rebecca Blackwell/AP Photo)





In this May 1, 2016 photo, 12-year-old Wilfrido Lemus Corona is raised aloft after winning the donkey race final with his burro “Veso” at the annual donkey festival in Otumba, Mexico state, Mexico. Family and friends threw the tiny jockey into the air Sunday after he scored his third consecutive win, claiming 12,000 pesos in cash, about $700 dollars. (Photo by Rebecca Blackwell/AP Photo)





In this May 1, 2016 photo, a team parades a donkey dressed as a firefighter, during the costume competition event at the annual donkey festival in Otumba, Mexico state, Mexico. The firefighter donkey finished second in the competition to win a prize of 7,000 pesos, or about $400 dollars. The annual donkey fair in this small town just north of Mexico City attracts up to 40,000 people who come to see the animals compete in costumes and race around a track with jockeys on their backs. (Photo by Rebecca Blackwell/AP Photo)





In this May 1, 2016 photo, donkey keychains are displayed for sale at the annual donkey festival in Otumba, Mexico state, Mexico. In addition to the main events, tourists and locals stroll through surrounding streets packed with donkey-themed souvenirs, food stalls, and fairground rides including live donkey and horse carousels. (Photo by Rebecca Blackwell/AP Photo)