Rio Carnival 2015: Extravagant floats and daring costumes, but also social issues... and Switzerland

Racial pride and the fight against racism in Brazil were the themes of the second night of Rio de Janeiro's samba school parades. Huge dance numbers celebrated Brazil's African heritage, and tribal art and African wildlife were recurring props.

Imperatriz Leopoldinense samba school built a giant Nelson Mandela float. The float was meant to remind people of his fight for equality, while calling for more racial integration in this South American country, which has more blacks than any nation after Nigeria.

Imperatriz Leopoldinense said it was inspired by an incident of racism in football, when a banana was thrown at Barcelona star Dani Alves during a match against Villarreal. The Brazilian player ignited a movement against racism by calmly picking up the banana and eating it before taking a corner kick. Imperatriz alluded to that incident with dozens of performers playing black-and-white harlequins inside peeled bananas.

"People think that discrimination in Brazil is a thing of the past," said Andre Bonatte, who helps coordinate cultural affairs for Imperatriz. "But we are here to say it is not like that. There are still many racist displays in our society."

Some say blackface makeup during Carnival is one such display. There have been complaints about Carnival street parties where people use blackface, including one called "Luxury Maids" in which white men wear black makeup and dress as servants.

"It is shocking that something so explicitly and ridiculously racist is being treated as a funny tradition worth preserving," wrote columnist Jarid Arraes, for Forum, an online magazine.

Beija-Flor paid tribute to the colours and rhythms of Africa, with special emphasis on Equatorial Guinea.

However, this caused controversy because the parade was partly paid for by President Teodoro Obiang, who came to power in a bloody coup and runs the country with an iron fist.

In a rather less likely tie-in, Unidos da Tijuca was partly sponsored by the Swiss government.

Their parade celebrated Swiss designer Clóvis Bornay and all things Alpine, with floats featuring snow and ice, and references to William Tell, St Bernard dogs and the creature from the Alien movies, designed by Swiss artist HR Giger.

The Portela samba school celebrated the 450th anniversary of Rio de Janeiro through the eyes of surrealist artists such as Salvador Dali.

But it wasn't all highbrow allegories and dodgy tie-ins. Uniao da Ilha school celebrated beauty, fame and fashion, with references to plastic surgery and gyms.

Their parade also featured a Lady Gaga lookalike in a meat dress, and Edna Mode, the eccentric fashion designer from the Pixar film The Incredibles.

Sao Clemente paid tribute to stage designer and Carnival legend Fernando Pamplona, with a macabre set peopled by witches, skeletons and Death (and, of course, hundreds of dancers in feathers and rhinestones).