Health & Medical

You are twenty minutes into a walk through long, dry grass in July. Your spaniel is having the time of her life. Then, out of nowhere, she stops dead and shakes her head. Not a casual shake but a violent, whipping fit that goes on far too long, and when she stops she holds her head tilted and paws at the ear. Nothing bit her. Nothing stung her. A grass seed has gone down the ear canal, and unless somebody takes it out, it is going nowhere but deeper.

Grass seeds, or foxtails, or awns if you want the botanical word, are among the few seasonal hazards most owners have never had explained to them properly. They arrive as the grasses ripen and dry off, usually from late spring to the end of summer, and they disappear once the seed heads have dropped. In between they cause an extraordinary amount of trouble. Wall barley and the various brome and foxtail grasses along field margins, verges and neglected corners of gardens are the usual culprits, and dogs collect them by walking past.

What makes them worse than any other bit of plant debris is the engineering. An awn is a slim, rigid spike covered in fine backward-pointing barbs, and that shape allows movement in one direction only. It is designed to work its way down into soil and stay there, and it does not care whether the medium is soil or a dog. Every muscle twitch, every step, every shake of the head ratchets it further forward. It never backs out. That is the single most important thing to understand, because it explains why waiting to see whether it works its way out is simply wrong. Awns do not work their way out, and they do not dissolve.

Ears take the largest share. A seed dropping into the canal is intensely irritating and the dog reacts instantly, which is why the sudden onset is so characteristic. One minute of normality, then frantic shaking. Dogs with long pendulous ears and feathery coats gather them best, so spaniels, setters and retrievers are the regulars, but any dog can pick one up. Left alone, the seed sits against the eardrum, sets up infection, and can eventually perforate it.

Feet are next. Seeds catch in the fur between the pads and in the webbing between the toes, and rather than falling out they pierce the skin and burrow in. What the owner notices, usually days later, is a soft painful swelling between two toes, often with a small weeping hole in the middle that never quite heals, and a dog who will not leave the foot alone. Licking is not the cause. It is the response.

Noses produce the most dramatic presentation of all. A dog snuffling through dry grass inhales an awn and the sneezing starts mid-walk, genuinely violent, in explosive runs, sometimes with a smear of blood from one nostril and a lot of face-rubbing. It may settle over the following days, which reassures owners and should not, because the seed is still up there and heading somewhere less convenient.

Eyes are the ones to treat as urgent. A seed lodged behind the third eyelid causes a suddenly squinting, streaming, painfully held-shut eye, and because the awn scrapes the cornea with every blink it can produce an ulcer quickly. Same-day attention, always. Less often, seeds bury themselves in the armpit or groin where the skin is thin. And in the nastiest cases a migrating awn travels into the chest, seeding infection into the space around the lungs and producing a very sick dog weeks after a walk everybody has forgotten. Cats are affected far less often, mostly in eyes and ears, but it happens.

Here is the part that catches people out at the vet's. Plant material barely shows up on X-rays, so a radiograph will almost never reveal the seed itself. Ultrasound in experienced hands sometimes locates one in soft tissue, and a CT scan may show the inflamed tract rather than the object at the end of it. Much of the time the diagnosis rests on the story you tell and is confirmed only when the seed comes out, which is why when the signs started matters so much. If the head shaking began in a hayfield, say so.

Retrieval is usually quick if the seed is still accessible: sedation or a short anaesthetic, a good look with an otoscope or endoscope, long crocodile forceps, and out it comes. Delay changes that picture completely. A migrated seed is no longer sitting in a canal waiting to be grabbed; it is at the far end of a tract of infected tissue, and finding it means surgical exploration with no guarantee of success first time. Abscesses that keep bursting and re-forming over months are the classic aftermath of a seed nobody chased. Waiting is not the cheap option. It is by a distance the expensive one.

Prevention is unglamorous and it works. In seed season, check your dog after every single walk, and make it a proper check rather than a pat. Run your fingers through and around both ears, feel between every toe including the webbing, and go over the armpits, groin, under the tail and along the belly. Feathering behind the legs traps seeds by the dozen and a quick brush shifts them before they find skin. Clipping the fur between the pads for the summer removes the most productive collection point on the whole dog. Keep your own lawn cut before it goes to seed, and when the verges are rattling with dry seed heads, walk somewhere else for a few weeks.

None of this needs to make you nervous about summer. It needs to make you observant. Sudden violent head shaking, a swollen toe with a weeping hole, sneezing fits that began in a field, or a squinting eye after a walk are all the same message, and the message is that today is the day to phone, not next week.