There is a bee bumbling about the winter jasmine, which belies the fact that we’re in November. Earlier I collected hay, anticipating colder days, but trundled home with the window down, past the cattle, which didn’t even turn their heads. Yet despite this sense of late autumnal ease, I’m disquieted. Our farm is under threat – not from climate change, nor the chancellor – but from our old foe, bovine TB. At our recent six-monthly test, a young steer was condemned as a “reactor”, our first for nearly six years. My neighbour doesn’t check his cattle between day one of the test, when they’re injected with avian and bovine tuberculin, and 72 hours later when the vet returns. But, having been through this before, when we lost almost 50% of our stock, I like to anticipate what’s coming; it means I’m emotionally and practically prepared when I’m told: “You’ve got a problem here.” Aside from the enormous swelling on the steer’s neck, it’s been evident that I’ve had a problem for some time. Badger-digging across the farm isn’t new, but with the end of the regional cull it is discernibly on the increase. More alarming, though, is an apparent change in their toilet habits. Long-established communal latrines could at least be fenced off, but they have been replaced by more indiscriminate behaviour. Yesterday, again, I stumbled across a random hollow containing fresh faeces, not seeming to relate to an inhabited sett or even a defined “run”. Cattle are curious creatures – they investigate by sniff or lick. If the excrement was from an infected badger, any contact would transfer the TB bacteria. I covered it over with earth, as I’ve been doing routinely, but it’s become a sinister game of “whack-a-mole”. Of course, badgers aren’t the only carriers. Troupes of six, seven, eight fallow deer commonly gather on the skyline east and west. They cross the farm balletically, deposit dung and doubtless use the water troughs; cross-contamination is possible. The postmortem on our steer reported “no visible lesions”, suggesting the infection was recent, though sceptics of the skin test would say that indicates no infection at all. On paper it looks like an isolated incident, caught in time. It could have been worse – but I can’t shake the feeling that it could be worse yet. Under the Changing Skies: The Best of the Guardian’s Country Diary, 2018-2024 is published by Guardian Faber; order at guardianbookshop.com and get a 15% discount