Red Mite (Dermanyssus gallinae), although small, can have a dramatic effect on your birds’ performance. Now warmer weather is approaching, keeping on top of red mite is paramount.
Now warmer weather is approaching, keeping on top of red mite is paramount. Warmth gives the red mite ideal conditions in which to breed and so numbers dramatically increase during warmer weather.
They tend to live in small cracks and crevices in the shed and around the system because they are nocturnal. The eggs that are laid in these areas take 2-3 days to hatch and only 7 days for this egg to become an adult mite. As a result, red mite infestations can spread very rapidly. A mite can also last for up to 8 months without food, making them very hardy.
The best time to spot red mite is first thing in the morning, after they have fed on the birds’ blood overnight, giving the mite their distinctive red colouring. Find a sheet of white paper and press it into any areas of the shed that look suspicious – red streaks should appear if mites are present. Low numbers of mites will cause irritation but because the breeding cycle is so quick, bigger issues can occur fairly rapidly. Large numbers of mites will cause birds to look anaemic and become lethargic. Combs will be pale rather than bright red and birds will be sitting hunched up. You may also see a drop in production and deterioration of shell quality. As a result of birds being under stress, blood spots may occur in the eggs. Ultimately, if the levels of red mite get out of hand, birds will lose condition and potentially a rise in mortality will be seen.
It is estimated that red mites cause the poultry industry across the UK and EU around £102m/year, with 87.5% of UK flocks effected. As a result, a vaccine for laying hens has been on trial commercially since 2015. Proteins that cause hens to produce an immune response were identified and injected into birds. Early trials proved that these proteins could be effective and birds who were treated harboured a quarter of the red mite, compared to the control birds and it has proven to cause around 35% mortality of mites. The issue is now scaling this vaccine up.
In the meantime there are an array of products on the market to help prevent and treat red mite. When using products in the water, be sure to flush your water lines after dosing. If the lines aren’t kept clean and flushed a build up of biofilm and bacteria can occur and cause birds to come under other challenges other than that of the red mite. For advice on which products to use for red mite please contact one of the members of our poultry team.