Clinical development and serological antibody responses in sheep and rabbits experimentally infested with Psoroptes ovis and Psoroptes cuniculi

Abstract

Psoroptes ovis of sheep origin, and Psoroptes cuniculi of rabbit origin were used in experimental infestations. In experiment I, groups of four rabbits and four sheep were infested with 50-100 mites of each isolate on the skin of the back (skin infestation, SI) or in the external auditory canal (aural infestation, AI). In rabbits, SI and AI with P. cuniculi and AI with P. ovis induced in all animals typical ear lesions and pronounced antibody reactions to P. cuniculi antigens in ELISA. After SI of rabbits with P. ovis no clinical signs were detected, no mites could be reisolated and no specific antibodies were detected. In sheep, P. ovis SI induced mange whereas AI did not induce typical clinical signs and mites could not be reisolated. In both these animal groups, ELISA revealed pronounced and comparable specific antibody reactions. After SI and AI with P. cuniculi no clinical symptoms were observed and no mites could be reisolated. Nevertheless, low levels of specific antibody were detected. In experiment II, clinical progression and antibody reactions to P. ovis SI in naive sheep were compared with sheep previously exposed to P. ovis or P. cuniculi. In both pre-exposed groups of animals, clinical signs appeared within 2 days after challenge infestation and three days earlier than in primarily infested sheep. Subsequently, no obvious difference in the clinical progression was observed between the three groups of animals. The results of this study document antigenetic crossreactivity of the two morphologically and genetically distinguishable Psoroptes species but differences in their biological behaviour and virulence which both are of epidemiological and taxonomic relevance.

Hormonal and behavioral changes induced by acute and chronic experimental infestation with Psoroptes cuniculi in the domestic rabbit Oryctolagus cuniculus

“…The control group underwent the same procedure, excluding the placement of mites [23]. To confirm that rabbits were infested, macroscopic lesions were identified with an otoscope.…”

Morphological and molecular comparison of host‐derived populations of parasitic Psoroptes mites

“…Boyce & Brown (1991) found only minor antigenic differences between mites from cattle, rabbits and bighorn sheep, and found mites from mule deer to be antigenically identical to those from bighorn sheep. Host transfer experiments of mites between rabbits and sheep have also shown that these mites are antigenically cross‐reactive (Siegfried et al ., 2004). A number of molecular studies have generated sequence data for the second internal transcribed spacer region (ITS‐2) of the ribosomal DNA.…”

Vaccination with recombinant actin from scab mites and evaluation of its protective efficacy against Psoroptes cuniculi infection

“…The amino acid sequence of rPc‐act showed high similarity to muscle actin genes in these species. Moreover, because of the distribution of the recombinant actin, which is mostly localized in the musculature, it can be classified as an isotype of muscle actin . Mounting evidence suggests that actin is involved in multiple processes during the life cycle of parasites and has critical importance in motility and endocytosis .…”

“…Afterwards, the interval was extended to 14 days before the last injection. Two weeks later, the left ear of each rabbit was challenged with 25–50 vigorous adult P. cuniculi mites and wrapped with gauze for 48 h. Weight and lesion areas of each rabbit were recorded once per week since the start of infestation. The lesion areas were measured by otoscope and flexible ruler.…”