This study is based on results from a large project on the mite diversity in commercial laying hen systems in Brazil. It aims to identify potential biocontrol agents amongst mites present in poultry farms, with a focus on one feather mite pest Megninia ginglymura. A secondary goal is to provide an operational identification tool to help the development of biological control in poultry farms. Sampling was conducted from August 2013 to August 2014, with 43 sampling events, in three different laying hen management systems. We used traps, laying hen feathers, and abandoned wild bird nests to collect the mites. A total of 38,862 mites belonging to 23 families and 39 species were found, including 17 species exclusively found in traps, six in wild bird nests, and one in feathers. The most abundant and frequent ectoparasitic species was M. ginglymura (76.3%; observed in all management systems). Amongst other mites, Tydeidae showed the highest richness with five species (Brachytydeus argentinensis (Baker, 1970), Brachytydeus australensis (Baker, 1970), Brachytydeus obnoxia (Kuznetzov and Zapletina, 1972), Brachytydeus oregonensis (Baker, 1970), and Brachytydeus tuttlei (Baker, 1965)), followed by Cheyletidae with four species (Chelacheles bipanus Summers and Price, 1970, Cheyletus eruditus (Schrank, 1781), Cheyletus malaccensis (Oudemans, 1903), and Cheletomimus (Hemicheyletia) wellsi (Baker, 1949)). Potential predatory species for biological control were C. malaccensis (9.4%), Typhlodromus transvaalensis (Nesbitt, 1951) (0.8%), Blattisocius keegani (Fox, 1947) (0.7%), and Blattisocius dentriticus (Berlese, 1918) (0.4%). A dichotomous key is provided to identify 48 species dwelling in Brazilian layer farms.

Intensive production of confined laying hens affects their welfare and increases the risk of epidemics. Ectoparasites as hematophagous and feather mites cause low productivity and decreased egg quality. This study aimed to determine the diversity of mites captured with traps in different commercial systems of laying hens (Gallus gallus L.) (Phasianidae) in Taquari Valley, Rio Grande do Sul, Brazil. Samplings were conducted from August 2013 to August 2014, totaling 21 sampling events in three different commercial laying hen systems: automatic production systems (A(1), (2), (3)), semiautomatic systems (S(1), (2)), and free-range system (FR). A total of 9981 mites belonging to 21 families, 31 genera, and 35 species were found. Acaridae, Caligonellidae, and Cheyletidae showed the highest richness with four species each. Megninia ginglymura (Mégnin, 1877) (Analgidae) was the most abundant ectoparasite species with 1328 specimens and was present in all commercial laying hen systems. No hematophagous mites were found. Cheyletus malaccensis(Cheyletidae) (3503), Typhlodromus transvaalensis (Phytoseiidae) (304), and Blattisocius keegani (Blattisocidae) (181) were the predators present in all systems. The similarity with control system (S(1)--without pesticide) was low (36.5 %) when compared to all other commercial laying hen systems, and it had the highest richness. In FR, low populations of mites and highest diversity were observed. The commercial laying hen system and the management influence the mite fauna in poultry farms.

Intensive egg production affects the welfare of confined laying hens, which increases the risk of epidemics. Ectoparasitic hematophagous mites and saprophagous feather mites cause low productivity and decreased egg quality. This study aimed to compare the biology of Cheyletus malaccensis (Oudemans) (Prostigmata: Cheyletidae) feeding on the prey Megninia ginglymura (Mégnin) (Astigmata: Analgidae) and Tyrophagus putrescentiae (Schrank) (Astigmata: Acaridae) in order to support the potential use of this predator in biological control strategies in the poultry industry. The study started with 30 eggs of C. malaccensis, isolated in experimental units, which developed into their different stages while feeding on the feather mite M. ginglymura and the stored product mite T. putrescentiae at 25±1ºC, 80±5% relative humidity and 12-hour photoperiod. Immature stages were evaluated three times a day and the adult stage once a day. Adult females were unmated. Cheyletus malaccensis feeding on M. ginglymura resulted in a higher fertility rate, with 310.7±45.8 eggs/female, than with T. putrescentiae as prey, with 32.7±4.5 eggs/female. Furthermore, the oviposition period was higher feeding on M. ginglymura, 53.0±6.3 days, than on T. putrescentiae, 12.6±1.9 days. The net reproductive rate (Ro), the innate capacity for increase (rm), the mean generation time (T) and the finite rate of increase (λ) were higher for the generation fed on M. ginglymura. Cheyletus malaccensis is a likely natural enemy of M. ginglymura, and it is able to develop and reproduce while feeding exclusively on it.

Ectoparasites are temporary or permanent skin dwellers. Megninia ginglymura (Mégnin) (Analgidae) causes economic damage in commercial poultry farms as a result of lower egg production or even death of the host. Little is known about Megninia ginglymura's life cycle and infestation. This study aimed to evaluate the preference of M. ginglymura for different body regions of the host Gallus gallus L. and its abundance and population dynamics in different laying hen houses. Samples were collected from August 2013 to August 2014 in three different commercial laying hen systems: automatic production systems (A1,2,3); semiautomatic systems (S1 (free of pesticides) and S2) and free-range system (FR). Ten laying hen were sampled each laying hen house and it were collected feathers were collected from different body regions form 10 hens in each laying house. A total of 28,305 specimens belonging to M. ginglymura were collected. Higher abundance was noted in S1 (9,234), S2 (9,121), and FR (5,873) and lower in A2 (2,211), A3 (1,628), and A1 (238). The dorsum (back of the body) region showed the highest abundance, mean abundance, and prevalence, representing 29.5% of the total specimens collected. The cloacal region was the second with 21.1% of the total of this ectoparasite. The abdomen and neck represented 20.8% and 19.6%, respectively. The inner wings presented the lowest abundance, mean abundance, and prevalence in all laying hen houses (9.0% of specimens). The prevalence was significantly different in automatic, semiautomatic, and free-range systems. The population peaks seems to coincide with periods of high temperatures and precipitation. Populations of this species already exhibit resistance to synthetic chemical pesticide.

We describe Tuccioglyphus setosus gen. et sp. nov. from the litter of commercially reared laying hens as well as wild birds in Brazil. The new genus Tuccioglyphus presents a mixture of character states between the two conventional subfamilies, Pyroglyphinae and Dermatophagoidinae. Based on this new unusual genus, we discuss character states delimiting these and other major subfamilies of the house dust mite family, Pyroglyphidae, as well as its most important and species-rich genus Dermatophagoides. An additional new genus, Marioglyphus gen. n., is proposed for Hughesiella valerioi Vargas and Smiley. Both Tuccioglyphus and Marioglyphus are related to the genus Hughesiella. A key to pyroglyphid genera of the World is presented.