02/20/2026
PYOMETRA CONTINUED...
Often, when pyometra is discussed, it quickly descends into an emotionally charged debate about neutering - if you simply remove their uterus they wouldn't get pyo.
What starts out as a discussion about how to mitigate the incidence of pyo quickly descends into Kaz, normally a lovely person, no doubt, hoping a stranger gets rabies.
Let's all just take a breath and consider the following:
Pyometra develops, it's thought, after repeated heat cycles in dogs that don't have pups at the end of it. Progesterone causes the uterine lining to thicken and at the same time suppresses immune defences in preparation for the new arrival that never comes. Fluid buildup then creates an ideal environment for bacteria (often ascending from the va**na), leading to infection and pus accumulation in the uterus.
Wild dogs (and dingoes and wolves) hardly suffer it at all, it's thought, because they mate. But as Beatrice highlights below, that's a myth. Most wild canids DO NOT get a chance to mate. In packs, you only have the leading male mating with the leading female and sometimes (if food is plenty) with the next female in order. The rest will NOT mate.
So that doesn't fit.
And then we have to consider the fact there is a strong breed effect - how can that be when they all have wombs and no litters?
So something else MUST be going on.
Here's the thing - raw promoting vets (and some groups in the UK have more than 30 on the books...) are reporting that pyo is seen far, far less in raw-fed dogs.
Now, you can take or leave that. I personally take it. They've not been wrong to date.
For years, they have been saying they are seeing far less bloat and pancreatitis in dogs and less kidney and dental disease in cats, too. Now the data is catching up. Soon we will have stats for cancer.
We all know that's high-carb kibble at play in those diseases. If you don't, read a book. Or a study. Or anything.
What was once definitely NOT related to diet is now pegged chiefly down to the (crap) diet.
YES you or your breed can be more disposed to INSERT ISSUE but, as they say, while genes may load the gun, environment pulls the trigger.
YES your breed may have a deep chest but if you feed him plant fibre that causes gas, you are risking bloat.
YES your breed may be more prone to kidney stones but meat based diets acidify the urine, making struvite crystal formation very difficult. High-carb kibble encourages them (particularly if DRY).
YES if your genes make you prone to breast cancer, don't eat sugar (including dogs...all the worrying studies are from dogs fed-high carb dry food, bet its far less likely in dogs fed right).
On and on.
Removing the uterus is one way to prevent pyo, but it MIGHT NOT BE the only way.
Simply recommending enormous operations without considering that seems a touch irresponsible, in my books, especially when removing the go**ds of a female dog has numerous downstream negative effects for the animal (see below, didn't want to bog down the piece).
At this point, folk always say "there are gonadal-sparing techniques" that our vets can do.
Yes "can" do, but don't do for the most part. I know of two vets in the UK doing so. None in Ireland. Any more out there, do let us know.
So, you forcing hysterectomies on dog owners dooms their pets to a a significant increase in numerous diseases, in the mistaken belief that aggressive neutering will reduce the amount of strays in a country being put down but this argument does not hold water. Ireland, UK and US have aggressive neutering policies in place and we have over-population problems too, compared to Sweden that does not recommend the practice and has no overpopulation problem.
Neutering IS NOT reducing our dog overpopulation problem. It's CLEARLY about enforcement of the laws we have in place, not hysterectomies.
Excess pups are coming from di****ad backyard breeders, di****ad puppy farms and di****ads as a whole (responsible people neuter / don't let their dogs wander).
Still today, the Irish govt tax incentivises puppy farms and does not punish owners of roaming dogs in any meaningful way. Sweden has automatic financial penalties in place for such owners. It's not rocket science.
The focus on the potentially harmful band-aid is increasing the risk of some nasty, lifelong issues for the dogs in question.
So, once again, we're all agreed if you don't have a uterus you won't get uterus issues....but let's keep our heads and explore a little further if diet is the petrol to the fire, before wishing viral deaths on everyone.
High-carb, plant-based kibble is perfect for E coli growth. Studies show dry-fed dogs have far more strains of E. coli in there than raw-fed dogs, most notably of B2 strain.
We know when meat eaters fed too much plant matter, particularly carbs, or heat-damaged proteins, this undigested matter hits the colon and feeds "other bacteria", like E.coli. It also alters the pH, allowing them to grow.
Now E.coli begin to competitively exclude the resident anaerobes like Clostridiales and Fusobacteria, which normally suppress E. coli, when they are resourced (fresh meat), and the process picks up pace.
But the invading B2 army needs an "easy ride" to infection-ville. Three things are needed for a successful invasion - numbers (check - high carb kibble grows it) but also the right terrain (check - intact bitch in oestrous) and finally weakened defences (numerous studies show high carb, ultraprocessed kibble is highly inflammatory for dogs, induces gut dysbiosis AND fuels gut disease, CHECK CHECK CHECK).
Dry feeding provides the numbers AND smashes the defences.
In the wrong dog at the wrong time, this is potentially devastating.
How much a part of the problem it is, remains to be seen.
IF THE ABOVE IS THE CASE WHY DID MY RAW FED DOG GET PYO.......because raw-fed dogs are not immune to gut dysbiosis and courses of antibiotics. While absolutely we know more dry-fed dogs suffer the condition, raw-fed dogs can get tummy trouble too, no doubt. The hormones involved in season-time alone are enough to fuel it. Add in a period of stress or a chemical wormer or illness, who knows. Anyone can get unlucky. It's just in dry-fed dogs, the bad guys are encouraged.
***
THE DOWNSIDES OF NEUTERING A BITCH TO AVOID PYO...THAT MIGHT BE DIET-RELATED...
❌ Neutered rotties have an approximate one in four-lifetime risk for osteosarcoma (versus the background figure of 0.1%).
https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2025.1532039/full
❌ Females neutered younger than 12 months have a markedly higher risk of developing hemangiosarcoma
https://pubmed.ncbi.nlm.nih.gov/2196736
❌ 7 % of German Shepherd females neutered before one year of age develop urinary incontinence vs 0 % of the intact females, in one cohort.
https://pmc.ncbi.nlm.nih.gov/articles/PMC5645870/
❌ Female dogs that keep their s*x hormones are 3 to 10 times more likely to be healthy in old age compared to those altered earlier.
https://pmc.ncbi.nlm.nih.gov/articles/PMC5861885/
❌ More than twice the risk of cruciate ligament rupture in neutered dogs.
https://pubmed.ncbi.nlm.nih.gov/39679821/
❌ Spayed females are about 5 times more likely to develop intervertebral disc herniation than intact females (and if spayed before 12 months, they were almost 10 times more likely to develop the problem).
https://pmc.ncbi.nlm.nih.gov/articles/PMC6236875/
❌ large cohort a**lysis reveals early gonadectomy is associated with far higher risk of osteoarthritis and other orthopaedic disorders.
https://pmc.ncbi.nlm.nih.gov/articles/PMC10713818/
❌ and contrary to popular belief, two recent studies found removing the s*x hormones of both males and females resulted in MORE aggression, not less (ranging from 20% more to double the level of aggression).
https://www.psychologytoday.com/ie/blog/canine-corner/201702/are-there-behavior-changes-when-dogs-are-spayed-or-neutered
