Laika was a mutt, part Siberian Husky, who was rounded up off the streets of Moskow and trained for space travel. The satellite was not designed to be recovered and when the batteries maintaining her oxygen supply died four days later, so did she... or so the official story went. Recent information indicates that for the first few hours after launch, Laika's heart beat normally, cabin pressure stayed steady and oxygen levels remained constant. Eventually, though, humidity and temperature began to increase. About five hours later, the telemetry system began to fail. No one is sure what happened after that, but Laika probably died then. The satellite, carrying her remains, reentered the atmosphere on April 14, 1958 and both were incinerated.
In 1960 the USSR was starting to test the Vostok spacecraft. On July 28, Bars (Panther or Lynx) and Lisichka (Little Fox) were killed when their rocket booster exploded during launch.
The next attempt at launching an animal into space was more successful. Strelka (Little Arrow) and Belka (Squirrel), along with 40 mice, 2 rats and a number of plants launched August 19, 1960 aboard Sputnki 5 (AKA Korabl'-Sputnik-2). They orbited the Earth 18 times. Later, Strelka had a litter of 6 healthy puppies. As a diplomatic gesture, one, Pushinka, was given to President John F. Kennedy as a gift. Although some people were worried about hidden microphones inside the dog, the president ordered her life spared. Pushinka caught the eye of Kennedy dog, Charlie, and when the pair had puppies, JFK called them Pupniks, in honor of the Soviet satellites.
The rest of 1960 wasn't as kind to the canine world or the Soviet space program. On December 1, Pchelka (Little Bee) and Mushka (Little Fly) were launched aboard Korabl-Sputnik-3 (AKA Sputnik 6). The launch went well, and the dogs spent a day in orbit, but there were problems with the retrofire burn and the reentry angle was too steep. The rocket and its passengers were burned up.
On December 22, another Vostok prototype was launched carrying Damka (Little Lady) and Krasavka (Beauty or Pretty Girl). The upper rocket stage failed and the launch had to be aborted. Damka and Krasavka completed a suborbital flight and were recovered safely.
1961 was a good year for the Soviets and their four legged cosmonauts. Sputnik 9 (AKA Korabl-Sputnik-4) was launched on March 9 carrying Chernushka (Blackie) on a one orbit mission. Chernushka's companions included a dummy cosmonaut, mice and a guinea pig. The flight was a success and Chernushka was recovered successfully.
Sputnik 10 (AKA Korabl-Sputnik-5) launched on March 25 with Zvezdochka (Little Star) and a dummy cosmonaut. It is said the Yuri Gagarin, himself, named Zvezdochka. Her one orbit mission was a success. On April 12, Yuri Gagarin followed the dog he had named into space to become the first human in space.
Kosmos 110 was launched on February 22, 1966 Verterok (Breeze) and Ugolyok (Little Piece of Coal). It landed safely on March 16, 1966 after a 22 day flight, setting a canine record for time in space, as yet unbroken. It wasn't even broken by humans until the Skylab 2 flight in June, 1974.
Although other animals have traveled into space in the intervening years, the "Golden Age" of canine cosmonauts ended with the Kosmos 110 flight.