All you ever wanted to know about red mite

Friday, February 13, 2015


The RED MITE, Dermanyssus gallinae, is a very prolific external parasite of birds which can be very difficult to eradicate – partly because the mite can survive for several months between feeds – so they are often in situ, just waiting for the arrival of a new flock!
Mites feed largely on blood of the birds, but also on feathers, skin or scales; each blood feed will take up to 2 hours after which the mite will leave the birds and return to hide in cracks and crevices in the poultry housing, where they lay their eggs, returning to the birds again the following night – hence, it is easy to miss their presence if examining a bird or coop during daylight.

Heavy mite infestations in chickens lead to high levels of stress and can result in anaemia, reduced egg production and, eventually if not treated, death, so the effects of red mite are of considerable economic importance when considering production costs not to mention animal welfare...

Additionally, mite can transmit diseases, such as the chicken pox virus, Newcastle Disease, fowl typhoid and salmonella as well as causing dermatitis and mange. When disturbed, they could also bite interfering humans and can cause a type of dermatitis. At one time it was thought that mite only tended to live in wooden structures, but they are now found on both plastic and metal – anywhere that is as near to their next meal as possible. Nowadays, they are also becoming increasingly common in battery cages, where they cause severe health problems and economic loss.

The tiny mite vary in appearance, depending on when they last fed – a mite is only red when it has consumed blood recently and changes colour again through black to grey as the interval between feeds increases. When checking housing areas for mite, a tell-tale ‘grey ash’ around crevices is evidence of mite faeces, but the best 
time to examine a house is at night, when the mite can often be seen with the aid of a torch, both on and off the bird.

 Symptoms of Red Mite Infestation.

  • Pale, ‘jaundiced’ faces and wattles, through anaemia
  • Depressed birds, lacking vitality
  • Emaciation – or even weight gain!
  • Decreased egg production
  • Increase in feed intake coupled with decreased egg production
  • Dark dots and speckles on normally plain eggs – they may be blood 
  • Spots or on closer inspection you may see the speckles move!
  • In extreme cases, feather loss and signs of dermatitis
  • Whitish-grey ‘ash’ (mite faeces) around the edges of crevices and in trails along and under perches.
  • Active red mite on housing which glow in the light of a torch at night. 
  • (Underneath the roofing felt is a favourite place for mite to hide!) 
  • Hens may avoid a nesting box which is particularly badly infected.


(Close up photo of Red Mite)

TIP; Never assume that red mite are the problem if you can’t find any physical signs of them at all – remember, most sick hens display some similar symptoms, whatever the cause! If in doubt – just ask us or a good avian vet.

The Red Mite Life Cycle.
Mites feed on the bird under cover of darkness each night and return to their crevices during the day MITE eggs are laid in crevices in the housing. Their tiny eggs are pearly white and oval, approx 0.4mm x 0.25mm. After 2-3 days, in warm conditions (longer in cooler weather), the eggs hatch into 6-legged larvae. Within 24 hours, the larvae moult into 8-legged prontonymphs, which start to feed on the roosting birds. Prontonymphs then moult into deutonymphs, which continue to feed, before moulting again to become adult male or female red mite. 

In warm, favourable conditions, this whole life-cycle can be completed within seven to ten days, which means that Mite populations in poultry housing grow very rapidly during the summer months, but Gradual climate change and warmer winters means that rather than being a problem which is only encountered during the summer, mite are now continuing to reproduce, though at a slower rate, through the winter, so need increased vigilance to keep populations in check. 

Mite can survive for several months without a feed and have been known to lie dormant for years! When hidden in cracks, they are very resistant to desiccation – so cleaning out and leaving a house empty will not prevent mite reappearing when birds are reintroduced! Mite can be carried by wild birds and prevailing winds, so can appear even when there has been no previous evidence of infestation.

Red Mite, in common with lice and other arachnids (spider-type creatures with eight legs) have a waxy exoskeleton (hard outer covering), without this shell, they will rapidly dry out (desiccate) and die. One of the best methods of attacking Red Mite therefore is to use a strong degreasing compound which dissolves the exoskeleton and rapidly kills the mite by desiccation. This method has the advantage that it is impossible for the mite to build resistance, a growing problem with many pesticides, and means that the same treatment can be applied repeatedly to keep the infestation under control. For this, we use and highly recommend Smite Professional.

Smite Professional is a specially selected, super-strength degreasant, disinfectant & cleaner, with excellent wetting properties, which has been proven highly effective at eliminating Red Mite in poultry housing. It is pleasant to use, for both the operator and the birds, is safe, economical, biodegradable and contains no pesticides.


TIP; Do Not water / pressure blast your coop – this will only disturb mite nests and spread them around and potentially cause a bigger problem for future coop treatment – we will cover more on this in part 2 of this news letter to follow in the coming weeks)

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5/7/2017 11:39 AM

Feather and weight loss

We have two red shavers, one has been losing feathers for months, at first they turned grey but now they are shedding faster. We dusted both of them (the other one has no signs of anything like this) scrubbed the coop with peroxide and then dusted them a few weeks later again. No sign of the little beggars.  She is much lighter and thinner then her mate and eats more.  Should we be peering in the coop with a torch at night do you think? Although if one chook has mites shouldn't they both?  Her skin is quite red where the feathers have gone from but otherwise she is really healthy. Her comb is red and upstanding also.  We are puzzled.