My border is nearly 5, male and is a solid 11kg. And has been for the last 3 years. I can feel his ribs, like you can if they’re a healthy weight but his waist isn’t the slimmest though not by much. Like maybe one up from ideal. But the vet always says oh he needs to lose weight he’s a heavy border. He is solid and muscular and maybe just a tad on the chunky side but the lowest he’s dropped in the last 3 years is 10.5kg.
his brother is a similar weight 10-11kg and his dad was a larger than average border, not particularly so but just that kinda 10-11kg rather than about 9kg.
mine gets borderline low end of the food average. He’s on canned butchers. And he doesn’t get too many treats, 2-4 biscuits a day when he comes in from the garden. And a piece of that bakers bacon. So not particularly a lot.
i know a lot of borders who are around 10-11kg and none are fat, they’re just solid and sturdy, rather than more lean.
ive read quite a few times in one of the bt groups on fb that the breed standard is a bit off, as many now seem to be larger. And that was from breeders who show and do well, not just a randomer, I know that doesn’t necessarily make them right but they’ve seen and met and had quite a few dogs.