The veteran horseman has questioned why Australia, as well as other Southern Hemisphere racing nations like New Zealand, has a breeding season that is conducive to foals being born in winter.

Currently, the Australasian racing season begins on August 1 and stallions can start covering mares a month later, on the first day of September.

With an average gestation period of just over 11 months, it means many mares that are covered in September give birth the following August.

Kent said that in his experience as both a breeder and a trainer, foals born later in the season are generally bigger than their August counterparts, with the climate and its impact on a mare's hormones a key factor.

"I don't like buying August foals," Kent said. "I'm not an expert on foals but I can tell you this - October-born foals are, on average, about 40kg heavier than August-born foals.

"Horses are meant to be born in the height of spring and that's when mares come into season naturally.

"A mare's metabolism improves into spring and they can finish off a foal better - they're able to put more into the foal.

"Why would we go against nature? I just look at the welfare of having mares in boxes, under lights and needling them up to come in season.

"A later foal is a much stronger, healthier foal and racing needs stronger, healthier horses."

Kent, who breeds his own horses as well as sourcing bloodstock from weanling and yearling sales, said that it would take only a minor change in dates to make a marked, beneficial difference.

Under his proposal, the racing season would begin on September 1 and stallions would be able to start covering mares a fortnight later, which would result in the bulk of foals being born from September onwards.

This spring alone, October and November-born horses made up more than 60 per cent of the Australasian-bred Stakes winners, including Melbourne Cup winner Verry Elleegant (foaled October 12), star sprinter Nature Strip (foaled November 16) and Godolphin's breakout three-year-olds Anamoe (foaled November 16) and Willowy (foaled November 25).

"At the moment you're not allowed to serve a mare until the first of September - I think we should push that back two weeks," he said.

"Two weeks is all it would take.

"Our racing season can move back a month to the first of September.

"I don't think you have to shift back any races - October and November foals already run as two-year-olds and win a lot of the best three-year-old races.

"It's a real myth to think that a foal born two months earlier is a bigger, healthier foal.

"I think it's a no-brainer."

Ryan Arnell, who runs Eddington-based broodmare farm Stonehouse Thoroughbreds, holds a similar view.

Although pushing the breeding season back is likely to have negative ramifications on his farm's bottom line, he said it would only be a positive for the welfare of the mares and foals he cares for.

Currently, breeders are often required to use artificial intervention to bring a mare into season for them to be successfully covered as early as September.

The motivations for having mares covered so early in the season can be many and varied, although common reasons include a desire to produce an 'earlier' foal for the yearling sales or to be able to maximise the number of foals a mare can have in consecutive seasons before she requires a year off.

"It's absolute insanity what we are doing," Arnell said.

"From a breeding perspective, October through to the summer months, even January and February, is the natural cycle for any horse breed, not just thoroughbreds.

"The increased cost of production to get these early foals is absolutely insane.

"We wouldn't have to put horses under lights, there'd be no need for these equilumes which everyone uses now, reproductive fees from vets would be reduced and there would be minimal issues because horses would be cycling of their own accord and not being forced to cycle with drugs.

"If we did change it, I'd probably lose money in my own business, but I'd be more than happy to do it for a sake of the horse."

Arnell believes a later breeding season would not have a major impact on the timing of yearling sales or how buyers view horses in a catalogue.

He said that many of the young horses with problems that he encounters are August-born foals.

"By March next year when a lot of the yearling sales are, some of our biggest horses will be November foals," he said.

"To be honest, it comes down to basic nutrition.

"When a foal is born, you want them on a rising plane of nutrition and that correlates with springtime and that's why the natural cycle of any anoestrus animal is that time of year.

"We're foaling them in the midst of winter in Victoria and they're not getting any nutrition out of any pastures until late September and into October, that's when the nutrition hits our pastures the best.

"Just on our farm, we've found that leg issues and deformities have been superior in August (foals) compared to any other month."

It's not the first time the issue has been raised and both Kent and Arnell admit that most of the resistance to change has traditionally come from Australia's larger, commercial stud farms.

A later start to the season has obvious potential to impact how many mares a stallion, particularly those that shuttle from the Northern Hemisphere, can serve.

Arrowfield Stud's Paul Messara is open to evolution, although he can understand both sides of the argument.

He said the biggest hurdle to pushing back the season was not necessarily getting the big players of the Australian breeding industry on board but instead their Northern Hemisphere counterparts, who operate an identical season during their spring.

Since the early 19th century, Northern Hemisphere-bred thoroughbreds have celebrated their 'birthday' on January 1, with most stallions in Ireland, England, Germany, Japan and the USA starting service from early February.

"I think the Southern Hemisphere probably came after the Northern Hemisphere so one of the things you'd have to do from a practical standpoint is for the Northern Hemisphere to change their season as well," Messara said.

"I don't know when the dates were set in stone but they (Northern Hemisphere) started breeding horses long before we did in Australia.

"They put the dates in the calendar and then we ended up going six months later, I think historically that's how things played out.

"In saying that, they have the same thing in the Northern Hemisphere when, in January, it's very cold, so it would make some sense for them to look at it as well.

"But it would have to be a worldwide thing, I don't think we could go out of sequence because it would mess up all the stallions shuttling here.

"Australia couldn't go one-out and say that we're going to make our breeding season start on October 1."

Despite the complexities that would need to be worked through on a global scale, Messara admitted that there is merit in the arguments of Kent and Arnell.

"Naturally, I think the horses are definitely better being born later," he said.

"I don't think anyone can argue that it makes sense from a natural standpoint.

"We have to artificially bring them into season to be ready to be covered on the first of September.

"I don't think it makes any difference commercially, it might just slightly adjust the sale dates.

"I don't think it would fundamentally change anything, it's just about getting everyone to agree on it."

Angus McKinnon is a specialist equine reproductive vet with decades of experience working with some of Victoria's largest thoroughbred breeding operations.

He also breeds his own horses and he said his personal preference was for his mares to be covered in October and November.

McKinnon said only a fraction of 'empty' mares cycle naturally in September, with many requiring artificial intervention, usually via the use of controlled lightning designed to replicate increased hours of daylight.

While this process doesn't harm the mare in any way, it allows them to fall pregnant earlier and often deliver a foal at a time of year that they would otherwise not be able to under natural conditions.

"I know the perception within the industry is that early foals can sometimes struggle in the weather and I believe that so I don't typically start breeding until later in the season as a result of that," McKinnon said.

"I'm not worried about sales, I'm only worried about having foals born at a time when I don't think they get that weather stress.

"That's my perspective as a breeder and an owner.

"From a veterinary perspective, my comment would be that, physiologically, a mare's breeding season is not aligned at all with the breeding pattern that we provide.

"It's that perception that early foals make more money that make people try to cheat the system and I'm not saying that perception is accurate but it's just what some people believe.

"Mares cycle according to long day and we trick them into cycling early, primarily by using lights - we provide them with 16 hours of light a day for about 60 days.

"Typically, we'll put a light mask on them or put them in boxes and leave the lights on from 4pm in the afternoon and leave them on until 11pm at night.

"Most of those mares will be ready to breed come September so you'll get the August foal."

While McKinnon can see benefits to shifting the breeding season back by several weeks in Victoria, he said that shifting the dates by a month or more could create unintended consequences if the change was mirrored in other, warmer parts of the country.

"We have to realise that whatever we do here (Victoria), is going to affect people further north," he said.

"I think it would be fine to put the season back in Victoria, I wouldn't question that because Victoria can be quite cold and we're a lot further south in latitude than northern New South Wales or Queensland so we don't enjoy warm weather early in the season.

"If you shift the whole season back then foals that are born in December or January would become the norm and in many places, that's not a good environment for a foal to be born.

"If you put (breeding season in) Queensland back by a month or two, you'll have foals being born that are then challenged by heat.

"Heat can be very challenging there, especially if the foals develop diarrhoea.

"In addition, if the seasonal rains don't come up north and things are dry then the dust can create really significant problems for respiratory disease in foals (commonly referred to as rattles).

"These typically wouldn't be as much of a problem earlier in the season."