Occurrence of yeasts in psittacines droppings from captive birds in Italy

Three-hundred twenty five droppings from parrots raised in the premises of 4 breeders and in several private households were cultured for yeasts. One-hundred sixty droppings (49.2%) resulted positive. From these specimens 212 isolates belonging to 27 different species were obtained. Mainly Candida species such as C. albicans, C. catenulata, C. curvata, C. famata, C. glabrata, C. guilliermondi, C. holmii, C. intermedia, C. krusei, C. lambica, C. lusitaniae, C. membranaefaciens, C. parapsilosis, C. pelliculosa, C. sake and C. valida were isolated. Debaryomyces marama, D. polymorphus, Geotrichum sp., Pichia etchelsii, P. ohmeri, Rhodotorula glutinis, R. rubra, Rhodotorula sp., Saccharomyces cerevisiae, S. kluyiveri and Zygosaccharomyces sp. were also obtained. Dark colonies on Staib medium were never observed. The psittacine birds apparently serve as carriers for several Candida species or their perfect states and to a lesser extent for other opportunistic yeasts such as Rhodotorula, Trichosporon and Saccharomyces spp., which are considered part of the transient microbiota of the gastrointestinal tract. The most striking finding was the absence of Cryptococcus spp. among the isolates. The present survey confirms the role of pet birds in carrying potential zoonotic yeasts. This revised version was published online in June 2006 with corrections to the Cover Date.     

Aspergillosis in Larus cachinnans micaellis: Survey of Eight Cases

Avian aspergillosis is reported in several avian species, with Aspergillus fumigatus as the main aetiological agent. Predisposing factors such as starvation, thermal stress, migratory stress, primary infectious disease or toxicosis may play a role. Eight cases of disseminated aspergillosis in free ranging seagulls sheltered at C.R.U.M.A. (Centro Recupero Uccelli Marini e Acquatici, Livorno, Italy) with different clinical histories are presented. The infection was demonstrated by cultural and histological methods from lesions of all birds, and the presence of airborne A. fumigatus viable elements ranging from 450 to 525 CFU/m³ inside and outside the shelter by means of a surface air sampler (SAS) Super-90 was also assessed. The role of this fungal species as an opportunistic factor in the captivity of seagulls is considered and some control measures, such as a clean and stress free environment and the use of antifungal drugs are suggested.     

Dermatophytes isolated from symptomatic dogs and cats in Tuscany,Italy during a 15-year-period

Between January, 1, 1986 and December, 31, 2000, dermatological specimens from 10.678 animals (7.650 cats and 3.028 dogs) were examined for dermatophytes. All the animals presented clinical signs of ringworm. Two thousand-four hundred fifty-six of the 10.678 (23%) examined animals scored positive for dermatophytes, 566 out of 3.028 canine (18.7%) and 1890 out of 7.650 feline specimens (24.7%). Microsporum canis constituted 83% and 97% of the isolated dermatophytes respectively in dogs and cats, M. gypseum represented 13% and 2.6% and T. mentagrophytes 5.5% and 0.2%. A sexual predisposition for mycotic infections was not observed. The animals with less than 1 year of age were more frequently infected. Canine toy breeds showed a significantly higher (P < 0.001) prevalence of infections by M. canis. Microsporum gypseum was mostly recorded from sporting (hunting) breeds [such as T. mentagrophytes (6.7%)]. Microsporum canis was isolated from long-haired cats with a ratio of 2:1 versus short-haired cats, while M. gypseum and T. mentagrophytes were never recovered from Persian cats. The annual distribution of the infections in dogs showed a significantly higher incidence for M. gypseum in summer versus winter and spring, while the recovery rate of M. canis from cats was very significantly higher in fall and winter than in summer and spring. Trichophyton mentagrophytes did not show a similar seasonal distribution.     

Altered cardiovascular responses to chronic angiotensin II infusion in aged rats

In this work we determined by telemetry the cardiovascular effects produced by Ang II infusion on blood pressure (BP) and heart rate (HR) in aged rats. Male Wistar aged (48-52 weeks) and young (12 weeks) rats were used. Ang II (6 microg/h, young, n=6; aged, n=6) or vehicle (0.9% NaCl 1 microl/h, young, n=4; aged, n=5) were infused subcutaneously for 7 days, using osmotic mini-pump. The basal diurnal and nocturnal BP values were higher in aged rats (day: 98+/-0.3 mm Hg, night: 104+/-0.4 mm Hg) than in the young rats (day: 92+/-0.2 mm Hg, night: 99+/-0.2 mm Hg). In contrast, the basal diurnal and nocturnal HR values were significantly smaller in the aged rats. Ang II infusion produced a greater increase in the diurnal BP in the aged rats (Delta MAP=37+/-1.8 mm Hg) compared to the young ones (Delta MAP=30+/-3.5 mm Hg). In contrast, the nocturnal MAP increase was similar in both groups (young rats; Delta MAP=22+/-3.0 mm Hg, aged rats; Delta MAP=24+/-2.6 mm Hg). During Ang II infusion HR decreased transiently in the young rats. An opposite trend was observed in the aged rats. Ang II infusion also inverted the BP circadian rhythm, in both groups. No changes in HR circadian rhythm were observed. These differences suggest that the aging process alters in a different way Ang II-sensitive neural pathways involved in the control of autonomic activity.     

Predator–prey interactions in a grassland food chain vary with temperature and food quality

Because species interactions are often context‐dependent, abiotic factors such as temperature and biotic factors such as food quality may alter species interactions with potential consequences to ecosystem structure and function. For example, altered predator–prey interactions may influence the dynamics of trophic cascades, affecting net primary production. In a three‐year field experiment, we manipulated a plant–grasshopper–spider food chain in mesic tallgrass prairie to investigate the effects of temperature and food quality on grasshopper performance, and to understand the direct and indirect tritrophic interactions that contribute to trophic cascades. Because spiders are active at cooler temperatures than grasshoppers in our system, we hypothesized that predator effects would be strongest in cooled treatments, and weakest in warmed treatments. Grasshopper spider interactions were highly context‐dependent and varied significantly with food quality, temperature treatment and year. Spiders most often reduced grasshopper survival in the cooled and ambient temperature treatments, but had little to no effect on grasshopper survival in the warmed treatments, as hypothesized. In some years, plants compensated for grasshopper herbivory and trophic cascades were not observed despite significant effects of predators on grasshopper survival. However, in the year they were observed, trophic cascades only occurred in cooled treatments where predator effects on grasshoppers were strongest. Predicting ecosystem responses to climate change will require an understanding of how temperature influences species interactions. Our results demonstrate that changes in daily temperature regimes can alter predator–prey interactions among arthropods with consequences for ecosystem processes such as primary production and the relative importance of top–down and bottom–up processes.     

Identification and seasonal distribution of airborne fungi in three horse stables in Italy

Fungal agents are responsible for a variety of respiratory diseases both in humans and animals. The nature and seasonal variations of fungi have been investigated in many environments with wide ranging results. The aims of the present report were (i) to evaluate the quality and magnitude of exposure to airborne fungi in three differently structured equine stalls (open air, partially and completely enclosed buildings) during a one-year period, using an air sampling technique and (ii) to compare the distribution and frequency of fungal species, with regards to these different environments. Air samples were collected monthly from December 2001 to November 2002 by means of a surface air sampler (SAS) Super-90, (PBI International, Milan, Italy). Penicillium and Aspergillus spp. were cultured from all the stables in all seasons. Mucoraceae were also recovered in all seasons in stalls 1 and 2, while they were not isolated in spring and fall in stall 3. These fungi were detected in 28.4%, 72.9% and 60.5% of the total number of samples, respectively. Other fungal genera such as Alternaria, Cladosporium, Fusarium, Beauveria and Drechslera were also occasionally recovered.Viable fungal concentrations varied greatly, ranging from below the limit of detection to more than 3000 CFU/m³ for stables 1 and 2, and 1750 CFU/m³ for stable 3. The median fungal concentration was approximately 178 CFU/m³. Total fungal concentration appeared to be highest in summer, winter and spring, and lowest in the fall.     

Dermatophytes and other keratinophilic fungi from coypus (Myocastor coypus) and brown rats (Rattus norvegicus)

The occurrence of mycotic agents was investigated by hair-brush technique on the coat of 162 naturalized coypus (Myocastor coypus) and 64 indigenous brown rats (Rattus norvegicus) originating from the same protected area in Central Italy. The isolates from positive coypus (29.6%) were identified as Microsporum gypseum (14.8%), Trichophyton terrestre (9.8%), Alternaria sp. (3.7%), Trichophyton mentagrophytes (2.5%), Cladosporium sp. (1.8%), Scopulariopsis sp. (1.2%), and Chrysosporium keratinophilum (0.6%), whereas the isolates from positive rats (46.7%) were identified as M. gypseum (28.1%), T. mentagrophytes (12.5%), Chrysosporium tropicum and T. terrestre (3.1% each), and Chrysosporium inops (1.6%). Statistically, brown rats were more likely to harbor fungal agents (P < 0.05) on their coat than coypus, especially T. mentagrophytes (P < 0.01) and M. gypseum (P < 0.05). No positive animal showed dermatological lesions. The present results are the first providing basic information on the coat’s mycoflora of a wild coypu population. It is concluded that the coypu, an allochthonous rodent in Italy, can play a role as natural animal reservoir of dermatophytes and as carrier of keratinophilic and saprophytic fungi within its new habitat, though to a lesser extent than indigenous rats. Therefore, people who are exposed to the risk of contact with the coat of rats and coypus should take all the cautions needed to protect themselves from mycotic agents potentially transmissible to humans.     

Identification of Malassezia species isolated from patients with extensive forms of pityriasis versicolor in Siena,Italy

BackgroundPityriasis versicolor (PV) is an infection caused by various species of Malassezia yeast. There is no agreement in the literature concerning the species of Malassezia and the demographic, clinical, and mycological data.AimsTo prospectively identify Malassezia species isolated from lesions of patients with extensive, long standing and recurrent forms of PV and to estimate the relationship between Malassezia species and the demographic and clinical data of the patients.MethodsAll patients with PV were enrolled over a four-year period. Malassezia species were isolated in cultures and identified by morphological features and physiological tests. In the last 2 years a PCR-based technique was used to confirm the species’ identification.ResultsA total of 74 patients (43 males and 31 females, mean age 39.5 years) were enrolled. Only one species was isolated in 45 patients, and more than one species were identified in the remaining 28 patients (38%). M. globosa was the most frequently isolated (60.3%) species. There was a significant association between the isolation of 2 or more species and the presence of at least one predisposing factor. In the last 29 cases, which were subjected to PCR, there were no differences in the identification of isolated species as compared to traditional methods.ConclusionsThe isolation of more than one species in a single lesion is not infrequent in PV and is related to the presence of one predisposing factor. The isolated species isolated were not influenced by demographic and clinical features. The traditional and more recent (PCR) procedures gave the same results in the isolated species.     

Detection of Leishmania infantum DNA in tissues of free-ranging red foxes (Vulpes vulpes) in Central Italy

To assess the role of the red fox (Vulpes vulpes) as a reservoir of leishmaniosis, 92 adult foxes of both genders (58 males and 34 females), shot during the regular hunting seasons in Central Italy, were examined. Blood samples were taken as well as samples from spleen, lymph nodes, and skin to investigate the presence of antibodies against Leishmania infantum and the presence of the parasite DNA in tissues, by means of a species-specific polymerase chain reaction, respectively. All tested sera were negative as well as skin samples. Forty eight animals (52.2%) had leishmania DNA in the lymph nodes and the splenic samples from eight of them (8.7%) scored positive also. The present report would indicate that foxes in an L. infantum medium-endemic area seem negligible reservoir for leishmania infection, even if more than 50% of them bear parasite DNA in their lymphatic tissue.     

Prey change behaviour with predation threat, but demographic effects vary with prey density: experiments with grasshoppers and birds

Increasingly, ecologists emphasize that prey frequently change behaviour in the presence of predators and these behavioural changes can reduce prey survival and reproduction as much or more than predation itself. However, the effects of behavioural changes on survival and reproduction may vary with prey density due to intraspecific competition. In field experiments, we varied grasshopper density and threat of avian predation and measured grasshopper behaviour, survival and reproduction. Grasshopper behaviour changed with the threat of predation and these behavioural changes were invariant with grasshopper density. Behavioural changes with the threat of predation decreased per capita reproduction over all grasshopper densities; whereas the behavioural changes increased survival at low grasshopper densities and then decreased survival at high densities. At low grasshopper densities, the total reproductive output of the grasshopper population remained unchanged with predation threat, but declined at higher densities. The effects of behavioural changes with predation threat varied with grasshopper density because of a trade-off between survival and reproduction as intraspecific competition increased with density. Therefore, resource availability may need to be considered when assessing how prey behavioural changes with predation threat affect population and food web dynamics.