It was a lovely warm summer’s evening last Thursday. The kids were in bed at 8.30pm and, after a quick cup of tea, I set about weeding the hedge at the side of the house. I’m certainly no Gerry Daly when it comes to gardening and true to form, the hedge should have been tended to about a month ago. I was waist deep in nettles, docks, thistles and everything in between.
What really struck me as I struggled at this hateful task was the massive amount of insects that I was disturbing. Spiders and flies erupted from every handful of weeds and to quote many a farmer, “the midges would ate you”.
To add insult to injury, I got bitten, through my t-shirt, by a horsefly. Luckily, I didn’t come across any dreaded ticks but you can be sure some were lurking in the undergrowth. This really is prime weather for creepy-crawlies. The main ones that are of concern to farmers and vets at the moment are flies and ticks.
Flies are a real nuisance. Only last week, I had one farmer call into the clinic looking for a fly-repellent pour-on as a matter of urgency. His cows had come into the parlour that morning and, such was the irritation that the flies were causing, he had one of the toughest milkings of his career.
Every cow’s tail was twitching, they were stamping their feet continuously and he would no sooner have one set of cups on when a cow would kick another set off.
Flies can cause serious irritation to cows and can really upset them. I have seen cows bunched together in a paddock, swishing their tails and arching their heads back to try to get flies to leave them alone. Cows will graze less and have a reduced milk yield if flies are a significant issue.
Outside of the “nuisance” factor, flies can also act as carriers of bacteria that causes some very harmful conditions in cattle. ‘Pink eye’ is a condition we are all very familiar with and many farmers have spent whole summers treating one calf after another for this nasty disease.
It is transferable when one calf contacts another, at a meal trough, for example, but flies are the main culprits. If you see an animal with pink eye, isolate them away from the rest of the group immediately and treat everything with a fly-repellent product.
Mastitis is another condition that flies can spread. In suckler cows, it is common for flies to spread mastitis after calves are weaned, or if the cows are dry. In dairy cows, flies can even be a cause of SCC spread as they can carry bacteria from the teats of a high SCC cow to an unaffected one.
There are many post-milking teat sprays that contain fly repellent and it is highly advisable to use one for the duration of the summer.
In dry cows, rubbing Stockholm tar on the udder is quite useful as well as using a fly-repellent pour-on. Any wound on an animal creates a high risk of fly infestation.
I remember, a few years ago, attending a cow two weeks post-Caesarian that had a surgical wound full of maggots. Luckily, very intensive treatment resulted in a positive outcome, but there have been many cases where the animal hasn’t been so lucky. Dehorning, in particular, is extremely risky at this time of year and should be avoided at all costs.
Anyone that owns sheep will be only too aware of the danger that flies can cause. Fly-strike is a condition where flies lay eggs in damp, dirty wool and maggots develop, eating into the skin of the poor affected ewe or lamb. Shearing away any dirty wool around the anus and perineum of all sheep at this time of year is vital to prevent this occurring.
As nasty as flies are, they are only trotting after ticks when it comes to severe illness. Red-water is the disease that is most synonymous with ticks in this country. It usually occurs in naive animals that are moved onto tick infested pastures.
Redwater is in reference to the port-wine colour of an affected animals urine. Initially, an animal with redwater will have a high temperature and an increased respiratory rate. As the disease progresses, the animal will become weak, lose its appetite and have very obvious pipe-stem diarrhoea – a nasty scour that shoots out of the animal as if from a hose-pipe.
There is one product available that acts as a preventative and as a treatment. Your vet will advise you on using this product and it is worth noting that the withdrawal for meat is quite significant – 213 days. Advanced cases need a blood transfusion in order to keep them alive. A tick-repellent pour-on is vital for any animals entering an area that is known to be infested with ticks, particularly old pasture, woodland or pasture near a lake or water course.
Tick-borne fever is a condition that has become more prevalent in our area in recent years. The intensification of the dairy sector has resulted in land that was previously almost idle, with hedges extending out 30 feet, suddenly being cleaned up and grazed by the money-making machines that are dairy cows. Like re-water, the majority of these cows will have never been exposed to tick-borne diseases before.
I have encountered herds of cows that have started to display pneumonia-like symptoms and a sudden, dramatic drop in milk yield. IBR would be top of the list of causes, but, blood samples have shown tick-borne fever in several herds. The spike in temperature associated with the condition can cause early embryo death – a disaster if the disease outbreak occurs at this time of year. Again, a pour-on tick repellent is vital.
Tick pyaemia is a condition that affects young lambs in particular. This condition causes abscesses in joints and in the spine of affected animals. The bacteria that cause the condition is carried by ticks. Affected animals can only be cured if caught very early in the disease process. By the time they are severely lame, the can be past the point of no return. As with other tick-related conditions, prevention is key, using an appropriate pour-on.
Don’t forget too that we can pick up nasty conditions from a tick bite, such as Lyme disease. There are tick and fly repellent products that humans can use too, so leave the pour-ons for the cows and talk to your local pharmacist.
Eamon O’Connell is a vet with Summerhill Vet Clinic, Nenagh