Immune responses of the domestic fowl to Dermanyssus gallinae under laboratory conditions

Abstract

There appear to be few reports in the literature regarding the host-poultry red mite (Dermanyssus gallinae) immunological relationship, despite the negative impact D. gallinae can have on both bird welfare and egg production, as well as its potential to act as a reservoir of zoonotic infections. The current study investigated the effect of either continuous infestation (CI) for 22 days or repeated infestation (RI) for four 24-h periods 7 days apart with D. gallinae on humoral immunity (IgM and IgY) and Th1/Th2 cytokine mRNA expression in peripheral blood mononuclear cells (PBMC) compared to non-infested controls. Serum IgY levels and IgM concentration were significantly higher in CI than RI and control birds although Th1 and Th2 mRNA expression in PBMC did not differ significantly between groups. D. gallinae appeared to modify reproductive behaviour and progeny survival following successive feeding events. In the RI group, the proportion of eggs/mite was significantly higher (P < 0.05) after first infestation than later infestations while larval/nymphal mortality was significantly higher (P < 0.05) after the first two infestations than later infestations. These data suggest that D. gallinae might adopt a feeding strategy of minimal host interference while D. gallinae could determine host immune status via nymphal/larval survival rates. Further research is required to better understand the host immunomodulation or avoidance strategy of D. gallinae as well as whether the mite is able to determine host immunocompetence perhaps using progeny survival.

Should the poultry red mite Dermanyssus gallinae be of wider concern for veterinary and medical science?

“…Confirming infestations based on blood testing is also difficult, with current techniques only being able to ascertain whether the host is responding to mites per se . Developments in this area to uncover host markers specifically for D. gallinae would be useful, though may be hampered as these mites are thought to adopt a feeding strategy of minimal interference [ 122 ]. Diagnosing D. gallinae in companion or livestock animals is likely to be equally problematic, with other ectoparasitic mites (such as the mange mite Sarcoptes scabiei ) being far more common on these hosts and presenting similarly.…”

Field evaluation of poultry red mite ( Dermanyssus gallinae ) native and recombinant prototype vaccines

“…After the removal of the PRMs on day 5, increases in IFNγ and IL-6 were observed; leading to the suggestion that PRM-mediated immuno-modulation of the host response may also be important for successful PRM feeding. Despite the lack of a clearly defined Th1/Th2 paradigm response, statistically significant increases in IgM and IgY levels, specific for PRM protein extracts, were observed over 22 days of infestation ( Harrington et al, 2010b ). This increase in IgY and IgM levels occurred concurrently with a decrease in the PRM oviposition rates, indicating a potential immunoglobulin mediated effect on PRM fecundity.…”

Challenges for the Control of Poultry Red Mite (Dermanyssus gallinae)

“…An experimental infestation developed an increase of the serum amyloid-A [35], but hens do not generate natural potent immunoprotective responses [36]. The development of an immune response by the bird after a chronic exposure is a plausible explanation which has been proposed that requires further research [34,37]. The type of hen hybrid and how they were raised as pullets seem to have some effects on the vertical distribution of the mite infestation in aviaries, which is explained by differences in the space use by different hybrids [38].…”