TY  - JOUR
A1  - Fischer, Stefan
A1  - Spierling, Nastasja G.
A1  - Heuser, Elisa
A1  - Kling, Christopher
A1  - Schmidt, Sabrina
A1  - Rosenfeld, Ulrike M.
A1  - Reil, Daniela
A1  - Imholt, Christian
A1  - Jacob, Jens
A1  - Ulrich, Rainer G.
A1  - Essbauer, Sandra
T1  - High prevalence of Rickettsia helvetica in wild small mammal populations in Germany
JF  - Ticks and Tick-borne Diseases
N2  - Since the beginning of the 21st century, spotted fever rickettsioses are known as emerging diseases worldwide. Rickettsiae are obligately intracellular bacteria transmitted by arthropod vectors. The ecology of Rickettsia species has not been investigated in detail, but small mammals are considered to play a role as reservoirs. Aim of this study was to monitor rickettsiae in wild small mammals over a period of five years in four federal states of Germany. Initial screening of ear pinna tissues of 3939 animals by Pan-Rick real-time PCR targeting the citrate synthase (gltA) gene revealed 296 rodents of seven species and 19 shrews of two species positive for rickettsial DNA. Outer membrane protein gene (ompB, ompAIV) PCRs based typing resulted in the identification of three species: Rickettsia helvetica (90.9%) was found as the dominantly occurring species in the four investigated federal states, but Rickettsia felis (7.8%) and Rickettsia raoultii (1.3%) were also detected. The prevalence of Rickettsia spp. in rodents of the genus Apodemus was found to be higher (approximately 14%) than in all other rodent and shrew species at all investigated sites. General linear mixed model analyses indicated that heavier (older) individuals of yellow-necked mice and male common voles seem to contain more often rickettsial DNA than younger ones. Furthermore, rodents generally collected in forests in summer and autumn more often carried rickettsial DNA. In conclusion, this study indicated a high prevalence of R. helvetica in small mammal populations and suggests an age-dependent increase of the DNA prevalence in some of the species and in animals originating from forest habitats. The finding of R. helvetica and R. felis DNA in multiple small mammal species may indicate frequent trans-species transmission by feeding of vectors on different species. Further investigations should target the reason for the discrepancy between the high rickettsial DNA prevalence in rodents and the so far almost absence of clinical apparent human infections.
KW  - Rickettsia helvetica
KW  - Rodent
KW  - Germany
KW  - Age
KW  - Reproduction
KW  - Season
Y1  - 2018
U6  - https://doi.org/10.1016/j.ttbdis.2018.01.009
SN  - 1877-959X
SN  - 1877-9603
VL  - 9
IS  - 3
SP  - 500
EP  - 505
PB  - Elsevier GMBH
CY  - München
ER  - 
TY  - JOUR
A1  - Mazza, Valeria
A1  - Dammhahn, Melanie
A1  - Eccard, Jana
A1  - Palme, Rupert
A1  - Zaccaroni, Marco
A1  - Jacob, Jens
T1  - Coping with style: individual differences in responses to environmental variation
JF  - Behavioral ecology and sociobiology
N2  - Between-individual differences in coping with stress encompass neurophysiological, cognitive and behavioural reactions. The coping style model proposes two alternative response patterns to challenges that integrate these types of reactions. The “proactive strategy” combines a general fight-or-flight response and inflexibility in learning with a relatively low HPA (hypothalamic–pituitary–adrenal) response. The “reactive strategy” includes risk aversion, flexibility in learning and an enhanced HPA response. Although numerous studies have investigated the possible covariance of cognitive, behavioural and physiological responses, findings are still mixed. In the present study, we tested the predictions of the coping style model in an unselected population of bank voles (Myodes glareolus) (N = 70). We measured the voles’ boldness, activity, speed and flexibility in learning and faecal corticosterone metabolite levels under three conditions (holding in indoor cages, in outdoor enclosures and during open field test). Individuals were moderately consistent in their HPA response across situations. Proactive voles had significantly lower corticosterone levels than reactive conspecifics in indoor and outdoor conditions. However, we could not find any co-variation between cognitive and behavioural traits and corticosterone levels in the open field test. Our results partially support the original coping style model but suggest a more complex relationship between cognitive, behavioural and endocrine responses than was initially proposed.
KW  - Coping styles
KW  - Faecal glucocorticoid metabolites
KW  - Learning
KW  - Stress
KW  - Personality
KW  - Rodent
Y1  - 2019
U6  - https://doi.org/10.1007/s00265-019-2760-2
SN  - 0340-5443
SN  - 1432-0762
VL  - 73
IS  - 10
PB  - Springer
CY  - New York
ER  -