Adaptation of mammalian host-pathogen interactions in a changing arctic environment

Many arctic mammals are adapted to live year-round in extreme environments with low winter temperatures and great seasonal variations in key variables (e.g. sunlight, food, temperature, moisture). The interaction between hosts and pathogens in high northern latitudes is not very well understood with respect to intra-annual cycles (seasons). The annual cycles of interacting pathogen and host biology is regulated in part by highly synchronized temperature and photoperiod changes during seasonal transitions (e.g., freezeup and breakup). With a warming climate, only one of these key biological cues will undergo drastic changes, while the other will remain fixed. This uncoupling can theoretically have drastic consequences on host-pathogen interactions. These poorly understood cues together with a changing climate by itself will challenge host populations that are adapted to pathogens under the historic and current climate regime. We will review adaptations of both host and pathogens to the extreme conditions at high latitudes and explore some potential consequences of rapid changes in the Arctic.     

Effectiveness of the homeopathic preparation Zeel compared with carprofen in dogs with osteoarthritis

The authors compared the symptomatic effectiveness of a complex homeopathic preparation Zeel (1-3 tablets orally per day depending on body weight) to carprofen (4 mg/kg body weight) in dogs (n=68) aged >1 yr diagnosed with osteoarthritis in a multicenter, prospective, observational open-label cohort study in 12 German veterinary clinics. The active treatment period was 56 days. Symptomatic effectiveness, lameness, stiffness of movements, and pain on palpation were evaluated by treating veterinarians and owners. Clinical signs of osteoarthritis improved significantly (P<0.05) at all time points (days 1, 28, and 56) with both therapies. At the end of the treatment period, effectiveness was comparable in both groups. Both treatment regimens were well tolerated with only three treatment-related adverse events, all in the carprofen group.     

Effects of poultry manure amendment on phosphorus uptake by ryegrass,soil phosphorus fractions and phosphatase activity

Poultry manure (PM) contains a large proportion of phosphorus (P) in mineral-associated forms that may not be readily available for plant uptake. In addition, PM application influences both chemical and biotic processes, and can affect the lability of native soil P. To investigate the effects of PM on soil P availability, we grew ryegrass (Lolium perenne) in greenhouse pots amended with poultry manure. Biomass was harvested at 4, 8, and 16 weeks following PM application, with soil separated into rhizosphere and bulk fractions. Soil was sequentially extracted by H₂O, 0.5 M NaHCO₃, 0.1 M NaOH, and 1 M HCl, and inorganic P (P_i) and enzymatically hydrolyzable organic P (P_oe) were quantitated. Root P concentrations were 37% higher and total P uptake 59% higher with PM application than Control. At week 16, there was 30% more labile-P_i (H₂O- plus NaHCO₃-P_i) in the rhizosphere with PM than in Control. Phosphodiesterase activity increased with PM application. Furthermore, acid phosphomonoesterase, alkaline phosphomonoesterase, and phosphodiesterase activities were all higher in the rhizosphere than in bulk soil at week 16 with PM, indicating that increased labile-P_i was due primarily to stimulation of soil phosphatases to mineralize NaOH-P_oe. Soil pH increased with PM application and plant growth, and may have promoted P availability by decreasing sorption of Al- and Fe-associated inorganic and organic phosphates. These results demonstrate that whereas PM application may initially increase NaOH and HCl-P_i, these fractions can be readily changed into labile-P and do not necessarily accumulate as stable or recalcitrant P in soil.     

Cortisol release and heart rate variability in sport horses participating in equestrian competitions

Equestrian competitions require both physical activity and mental adaptation in horses. Cortisol, heart rate, and heart rate variability (HRV) are accepted stress parameters and, in this study, have been determined in horses (n = 13) participating in equestrian competitions for up to 3 consecutive days. Participation in competitions caused an increase in salivary cortisol concentrations (e.g., on day 1 from 1.0 ± 0.2 before to 2.2 ± 0.4 ng/mL after the competition, days 1 and 2: P < 0.001, day 3: P < 0.05) and an increase in heart rate (days 1 and 2: P < 0.001, day 3: P = 0.01). A consistent decrease in HRV occurred only in response to the final competition on day 3 (P < 0.01). When horses competing in dressage and show jumping were compared, cortisol release and HRV did not differ between groups, but after the competition, heart rate was lower in dressage than in show jumping horses (P < 0.05). Heart rate increased not only during the actual competition but already when horses were prepared in their stables (e.g., day 1: ?60 minutes, 38.6 ± 2; ?5 minutes, 77 ± 7; competition, 81 ± 10 beats per minute; P < 0.01). In conclusion, participation in equestrian competitions caused an increase in cortisol release and heart rate and a decrease in HRV variables. However, competitions were not a major stressor compared with other anthropogenic challenges such as transport, to which horses are exposed regularly.     

The native South American crayfishes (Crustacea,Parastacidae): state of knowledge and conservation status

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Gattungsgrenzen bei höheren Discomyceten

Zusammenfassung An Hand besonderer Discomyceten-Funde aus dem Jahre 1961 werden einige Nachbargattungen miteinander verglichen und ihre gegenseitigen Grenzen kritisch erörtert. Danach erweist sich die Sonderstellung vonPtychoverpa Boud. nur mikroskopisch als ausreichend begründet.Helvella Quéletii Bres. kann vonAcetabula sulcata (Pers. ex Fr.) Fuck. nicht gattungsmäßig getrennt werden, sondern ist alsAcetabula Quéletii (Bres.) Bx. nov. comb. zu bezeichnen, wenn beide Gattungen nebeneinander bestehen bleiben.Paramitra ochreoides Bx. nov. gen. et nov. spec. wird erstmalig beschrieben und stellt vermutlich einen Übergang von derOtidea-Gruppe (Wynnella Boud.) zu den Aleurieen dar.

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Summary Starting from rare findings ofDiscomycetes in 1961 some closely related genera are compared and their limits discussed critically. The special position ofPtychoverpa Boud. is sufficiently proved only by microscopic characters. To discernHelvella Quéletii Bres. fromAcetabula sulcata (Pers. ex Fr.) Fuck. generically is not possible, it must be designated asAcetabula Quéletii (Bres.) Bx. nov. comb. if both genera shall be maintained. The new describedParamitra ochreoides Bx. nov. gen. et nov. spec. presumably is a transitional fungus between theOtidea-group (Wynnella Boud.) and theAleurieae.

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, 1961 . . Ptychoverpa Boud. .Helvella Quéletii Bres. Acetabula sulcata (Pers. ex Fr.) Fuck. Acetabula Quéletii (Bres.) Bx. nov. comb., .Paramitra ochreoides Bx. nov. gen. et nov. spec. ; Otidea (Wynnella Boud.) Aleurieae.

     

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Zur Anwendung organischer Phosphorsäureverbindungen in der Fliegenbekämpfung

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