HBO's Silicon Valley, centered on the startup company lifestyle, has a certain reputation for outrageous humour; having already delivered a near-instantly iconic scene in which the guys embark on an intense mathematical calculation as to how to manually pleasure an entire conference audience. Turns out, there's a surprising amount of formulas and fractions involved.

A scene now likely topped by a certain outrageous sequence included in the show's latest episode, in which two thoroughbred horses are seen having sex while Richard Hendricks (Thomas Middleditch) attempts to have a serious conversation about the industry with Jack Barker (Stephen Tobolowsky). And, yes, it was 100% real.

Unfortunately, PETA failed to see the funny side of the sequence. Though the Hollywood Reporter claims the American Humane Association were present on location, a Californian breeding farm, for the scene and awarded the episode a "No Animals Were Harmed" certificate, the animal-rights organisation has branded the very practice of thoroughbred mating as "arranged rape".

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PETA spokesperson Lisa Lange stated, "It may seem fun, but the mares are tethered during the process with no means of escape and the stallions are put on a lead rope and dragged to the mares to be mounted. Neither the stallions or the mares have any choice, it’s assembly line breeding for profit."

"There’s an overpopulation crisis in racing as most horses will not win races, and are therefore discarded and sent on hideous journeys by truck in all weather to Mexico or Canada to be turned into meat."

However, Mark Stubis of the American Human Association states the scene was filmed, "naturally, documentary style, on an actual horse breeding farm with no interference with the animals in any way by production. Breeding professionals were on hand to make sure everything went smoothly."

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"An American Humane Association Certified Animal Safety Representative was on set during the filming of the scene, as was a veterinarian who checked both horses prior to shooting the scene," he adds. "Production was very cooperative from the first stages of informing American Humane Association to the day of filming."

The scene, at least, seems to have been a hit at HBO, with the show's creator Mike Judge joking; "I actually have an email from [Senior VP of Comedy Programming] Amy Gravitt where she said, ‘I can’t believe I’m saying this, but can we have more screen time with the horses having sex?’ So we put in more shots."