Dermanyssus gallinae

Dermanyssus gallinae (also known as the red mite) is an ectoparasite of poultry and has been implicated as a vector of several major pathogenic diseases. Despite its common names, it has a wide range of hosts including several species of wild birds and mammals including humans. In both size and appearance, it resembles the northern fowl mite, Ornithonyssus sylviarum.Immature form Nymph I of Dermanyssus gallinae by A.C. OudemansImmature form Nymph II of Dermanyssus gallinae by A.C. Oudemans Dermanyssus gallinae (also known as the red mite) is an ectoparasite of poultry and has been implicated as a vector of several major pathogenic diseases. Despite its common names, it has a wide range of hosts including several species of wild birds and mammals including humans. In both size and appearance, it resembles the northern fowl mite, Ornithonyssus sylviarum. The mites normally feed around the breast and legs of hens, causing pain, irritation, and a decrease in egg production. Pustules, scabs, hyperpigmentation and feather loss may develop. If they are present in large numbers, D. gallinae can cause anemia in hens which presents as pallor of the comb and wattle. D. gallinae is an obligate blood feeder that will normally attack its host at night, but will occasionally feed during the day. Adults (0.75–1 mm long) have long legs and usually a grayish- white body, which becomes reddish-brown when engorged. After feeding, they hide in cracks and crevices away from light sources, where they mate and lay eggs. The mite progresses through 5 life stages: egg, larva, protonymph, deutonymph and adult. Under favourable conditions this life cycle can be completed within seven days, so populations can grow rapidly - causing anaemia in badly affected flocks of poultry. Young birds are most susceptible. The mites can also affect the health of the birds indirectly, as they may serve as vectors for diseases such as Salmonellosis, avian spirochaetosis and Erysipelothrix rhusiopathiae. Red mites can survive for up to 10 months in an empty hen house, temperatures greater than 45 °C/113 °F and less than -20 °C/-4 °F, have been found to be lethal.