Vets gave two lion cubs a check-up before they were displayed at a zoo in Thailand.

Staff inspected the male cub Phupha and the female named Tara before in preparation for their exhibit at the Khon Kaen Zoo in Khon Kaen province on March 8.

Footage shows the young lions snarling at the staff as they underwent the tedious medical routine.

The pair were given distemper vaccines, and their weight, length and teeth size were measured. Their stool samples were also tested.

Zoo director Narongwit Chodchoy said Phupha weighed 10 kilos, while Tara weighed eight kilos. Both of them were healthy.

He said: 'Currently, the natural population of African lions is estimated at 23,000 to 39,000. They are listed as a vulnerable species.

'It is important to support their health so that their population can increase. This check-up was done in preparation for the zoo's lion exhibition soon.

The cubs were born to lioness Kanya and her mate Singha last December 23 at the Khon Kaen Zoo. Both parents were relocated from the Ubon Ratchathani Zoo.

The International Union for Conservation of Nature Red List classifies the African lion as 'Vulnerable.'

The big cats face dwindling populations due to 'indiscriminate killing in defence of human life', habitat loss, and prey base depletion linked to poaching.