When the news broke on Saturday evening of the passing of champion racehorse Black Caviar, I knew tributes and accolades would immediately begin to flow, and for good reason.

From social media platforms to news headlines, the discussion was dominated by memories of the iconic mare's astounding 25 wins from 25 starts, marking one of the most impressive careers in racing's modern era.

Many outside of the racing industry, or those without a strong interest in the sport, may have presumed she had spent her final years in pampered peace, having earned the right for a restful retirement in some far off green and pleasant land.

In truth, the deafening cheers of hysterical crowds may have abated when jockey Luke Nolen dismounted in 2013 for the final time, but Black Caviar's hardest job hadn't yet begun — the more successful a racehorse on the track, the higher value they are for breeding.

When I was invited for a rare visit to see Black Caviar in 2016 at her stud farm, in a secret location in the Hunter Valley, I gained important insight into the less known side of her new reality.

At the time, working as a general news reporter and feature writer for an Australian tabloid, I knew little about horse breeding but sometimes naive eyes are useful. They bring new perspective and spark impertinent questions.

Ostensibly, Black Caviar seemed content enough when I arrived, as I patted her in a pretty paddock alongside her second foal.

They nibbled on the grass in the dappled shade of the February sun within eye shot of other notable mares and stallions in surrounding fields.

The stud was staff-heavy with young assistants in jaunty Akubra hats and friendly managers busily organising an abundant BBQ lunch for several of Black Caviar's wealthy owners who were also on the visit.

It was when I sat down after the lunch and interviewed one of the stud managers that one of his chatty, relaxed answers stopped me in my tracks. 

He was talking me through how the impregnation process worked for Black Caviar and casually revealed that they had to use a "twitch" restraint device on her face, which they could tighten if she protested when a prized stallion mounted her. Or "covered" her as they say in the horse breeding industry.

The risk of injury for both valuable animals is high in this acute and challenging moment of copulation so this device, which can consist of a small twisting rope, was considered vital. It stilled her. It made her compliant.

I could tell this was normal and acceptable in the horse breeding world, but as an outsider I felt uncomfortable. Was this fair to Black Caviar after all she had achieved? How painful was this restraint? Was this method kind to any broodmare, a champion or not? 

Most importantly, I felt that the millions of Australians who still adored this horse, embedded in our collective history and memories, should know the facts.

My editors at the time had other ideas. They were happy with a more positive piece about Black Caviar's new life as a mum and sweet pictures of her beautiful latest foal. 

The racing industry holds a lot of power in media advertising and many readers buy tabloids for the racing pages. Alienating or angering these stakeholders was perhaps too much of a risk.

I did my best to push back and hint at some concern in my articles and then had to move on, presuming the beloved horse would only have, perhaps, a couple more foals before finally living out her final years in peace.

When she died at the weekend she had been suffering from a severe hoof disease and was euthanised shortly after giving birth to her ninth foal, a colt, in 11 years.

Nine. The sheer number seemed surprising. 

Had the foot disease been caused by being worn down by the close succession and sheer weight of her lengthy pregnancies? Each time she gave birth she had clearly soon been impregnated at the stud again, with the gestation time being, on average, around 340 days.

Laminitis, which is what caused Black Caviar to be euthanised, can occur due to many reasons, including excessive weight bearing, fillies and mares coming into season, cold weather, infections and toxaemia, retained placenta, and drug inducement.

None of her foals, many trained by Peter Moody, have yet proved to be able to match her winning streak. 

Last November her fifth foal, named Invincible Caviar, tragically died during training in a swimming pool while several others, including Prince of Caviar and Out of Caviar, have already been retired to stud.

Their heritage alone ensures they are valuable breeding commodities bringing further gains to their owners. Even her stallion sons can command over $4,000 per "cover" according to racing media. 

And so the cycle goes on.

Breeding and its spoils are part of the on-going prize for owners and syndicates of retired champion racehorses with often multi-million-dollar gains, either at the yearling sales or to keep as future runners and breeders themselves.

Black Caviar was one day shy of her 18th birthday when she died. The expected life span of a retired racehorse is between 25-30 years old.

When I wrote what turned out to be a viral thread on Twitter at the weekend, about my 2016 Black Caviar visit, this longevity point seemed to cause most concern.

The posts gained nearly 500,000 impressions, according to the site's analytics and attracted dozens of comments.

Many felt Black Caviar had been "bred excessively" with one user saying the racing industry was "always about the money and not about the animals".

"It's essential people know the truth and understand the money-focus of all animal breeding programmes," another user wrote.

Other racing fans had other views, arguing that twitch restraints are not painful for horses, and that mares in the wild have one foal every year anyway.

Of course, her experience could only be gained from the adored mare herself, the horse famously admired by the late Queen when she was flown across the globe to race at Royal Ascot for yet another glorious win.

Vale Black Caviar — the most important interview Australia could never have.

Lucie Morris-Marr is a Walkley-winning author and freelance investigative journalist based in Melbourne.