Pruritic Facial Dermatitis in a Population of Free-living Stitchbirds

Abstract

ABSTRACT:From September 2001 to February 2005, observations of an island population of the New Zealand stitchbird (Notiomystis cincta) revealed a progressive feather-losing dermatitis, which developed during the breeding season around the birds' eyes, base of the bill, and ventral neck. The lesions were significantly more likely to develop in males (96%) than females (51%), with males exhibiting a more severe form of the condition at the end of the breeding season. Histology from a dead bird revealed the presence of ovoid burrowing mites within the lesions, and isolation of mites from skin crusts of a live bird were identified as Knemidocoptes spp. Although other factors might be involved in the expression of the condition, Knemidocoptes appears to be a likely causative agent in the development of skin lesions in this population.

Sub-lingual oral fistulas in free-living stitchbirds (Notiomystis cincta)

“…In other avian species, crop fistulas are known to occur more commonly in neonates presumably because the crop is more fragile and susceptible to injury than in adults (Ritchie et al ., 1994). One possibility that has not been previously considered is a relationship between Knemidocoptes infections and the development of the fistulas (Low et al ., 2007). However, there is currently no evidence that birds displaying mite lesions are any more likely to suffer from an oral fistula.…”

KNEMIDOKOPTINID (EPIDERMOPTIDAE: KNEMIDOKOPTINAE) MITE INFESTATION IN WILD RED-CROWNED PARAKEETS (CYANORAMPHUS NOVAEZELANDIAE): CORRELATIONS BETWEEN MACROSCOPIC AND MICROSCOPIC FINDINGS

“…As P. janssensi was predominantly found in feather follicles, skin scrapings used to detect knemidokoptinid mites in other species and studies (Dabert et al 2011) are unlikely to be as sensitive, although this was not evaluated in this study. Issues of detection sensitivity for Knemidokoptinae using skin scrapes have been reported (Low et al 2007), highlighting the importance of obtaining the right specimen based on the biology of the mite species involved. Shoshana (1993) successfully used 25 plucked feathers to look for mites in RCP with feather loss.…”

“…Dermal changes are less common and may include a perivascular mononuclear infiltrate (Mason and Fain 1988;Ladds 2009) or a heterophilic infiltrate (Fletcher 2008). Subcorneal pustules and mites burrowing beneath the stratum corneum have also been reported (Low et al 2007).…”

“…Historically, the literature has focused on those of significance to poultry and caged birds, including ''scaly face'' (Knemidocoptes pilae; Lavoipierre and Griffiths 1951) in budgerigars (Melopsittacus undulates; Yunker and Ishak 1957), depluming itch (Neocnemidocoptes gallinae and Picicnemidocoptes laevis; Pence 1972) in poultry and pigeons, respectively (Fain and Elsen 1967) and scaly leg (Knemidocoptes mutans; Robin and Lanquetin 1859) in poultry (Morishita et al 2005). Knemidokoptinid mange has been considered uncommon in wild birds (Mainka et al 1994); however, in the past 15 yr, there has been an increase in reports of these parasites in a range of wild birds (Mainka et al 1994;Ladds 2009;Dabert et al 2011;Dabert et al 2013), particularly Passeriformes (Mason and Fain 1988;Jaensch et al 2003;Holz et al 2005;Low et al 2007;Gaudioso et al 2009).…”