The two dogs Travis, 10, and Gus, 5 have become an Internet hit on Instagram. These images were taken by Canadian photographer Steph McCombie. (Photo by Steph McCombie/Instagram)

Barny, the Harveys Brewery dog has a sniff of a pint of beer at the Great British Beer Festival, at Olympia in London, Tuesday, August 11, 2015. The five day event is organised by the Campaign for Real Ale (CAMRA), with over 900 real ales, ciders, perries and international beers on offer. (Photo by Kirsty Wigglesworth/AP Photo)

A Filipino pet owner carries her dog as she prays before the animal blessing rites at the Our Lady of Remedies Parish Church in Malate district, Manila, Philippines on Sunday, October 5, 2014. Several Filipinos brought their pets to be blessed during the annual event which is also done to celebrate the feast day of St. Francis of Assisi, the patron saint of animals and ecology. (Photo by Aaron Favila/AP Photo)

Colleen Kelley, of Iowa City, Iowa, fixes the hat on her dog Bruce during judging at the 35th annual Drake Relays Beautiful Bulldog Contest, Monday, April 21, 2014, in Des Moines, Iowa. The pageant kicks off the Drake Relays festivities at Drake University where a bulldog is the mascot. (Photo by Charlie Neibergall/AP Photo)

An undated archive picture shows a dog pulling a Belgian machine gun at an unknown location in northern France. A Viscount in the Armoured Cavalry Branch of the French Army left behind a collection of hundreds of glass plates taken during World War One (WWI) that have never before been published. The images, by an unknown photographer, show the daily life of soldiers in the trenches, destruction of towns and military leaders. The year 2014 marks the 100th anniversary of the start of WWI. (Photo by Collection Odette Carrez/Reuters)

Members of the Old Surrey Burstow and West Kent Hunt ride to Chiddingstone Castle for the annual Boxing Day hunt in Chiddingstone, south east England December 26, 2014. Since a ban stopped fox hunting with hounds, hunts continued with dogs chasing down a pre-laid scented trail instead of a fox. (Photo by Luke MacGregor/Reuters)

Rebecca Smith poses for a photograph during winter solstice with her Irish Wolfhound dog called Amazing Grace at the 5000 year old stone age tomb of Newgrange (not in view) in the Boyne Valley at sunrise in Newgrange, Ireland, December 21, 2016. (Photo by Clodagh Kilcoyne/Reuters)