Effects of water extracts from chicory and BHT on the in vitro rumen degradation of feeds.

Effects of Butyl-Hydroxyl-Toluene (BHT) and of Red Chicory Extract (RCE) on kinetics of gas production (GP) and rumen degradability values (OMd, NDFd and in vitro true OM degradability - IVTOMD) of two feeds (meadow hay and corn meal) were evaluated using an in vitro automatic batch system. For each feed 2 increasing dosages (0.15 and 1.5 mg/g of feed) of BHT and RCE and a Control (C) were tested in 4 replications and 2 incubations. First incubation lasted 72h, the 2nd one was stopped at the times on which half of GP was produced (t½), which were 9 and 16 h for corn and hay, respectively. From the supernatants of the 2nd incubation, VFA, NH3, N content of the residual NDF were analysed and the microbial N balance was computed. The 2 feeds significantly affected rumen fermentation parameters; BHT significantly increased asymptotic GP, t½ and IVTOMD (P<0.01), decreased the proportion of butyrate (P<0.01) but did not affect microbial N balance; RCE did not influence any of the parameters measured with respect to C, except for a significant increase of the estimated N available for microbes at the higher dosage

Linking food web functioning and habitat diversity for an ecosystem based management: A Mediterranean lagoon case-study

We propose a modelling approach relating the functioning of a transitional ecosystem with the spatial extension of its habitats. A test case is presented for the lagoon of Venice, discussing the results in the context of the application of current EU directives. The effects on food web functioning due to changes related to manageable and unmanageable drivers were investigated. The modelling procedure involved the use of steady-state food web models and network analysis, respectively applied to estimate the fluxes of energy associated with trophic interactions, and to compute indices of food web functioning. On the long term (hundred years) temporal scale, the model indicated that the expected loss of salt marshes will produce further changes at the system level, with a lagoon showing a decrease in the energy processing efficiency. On the short term scale, simulation results indicated that fishery management accompanied by seagrass restoration measures would produce a slight transition towards a more healthy system, with higher energy cycling, and maintaining a good balance between processing efficiency and resilience. Scenarios presented suggest that the effectiveness of short term management strategies can be better evaluated when contextualized in the long term trends of evolution of a system. We also remark the need for further studying the relationship between habitat diversity and indicators of food web functioning

Spatio-temporal re-colonization of top-predators modulates zoonotic infections in ticks

Introduction and objectives: Predator community can change abundance and composition of their preys, affecting emergence and spread of tick-borne infectious diseases for which some preys (e.g., ungulates, rodents) are often common hosts. We aim to evaluate if sites with gradual temporal re-colonization of a top-predator, the wolf (Canis lupus), exhibit different infection prevalence in ticks. Materials and methods: We identified four study areas (NV = Non Valley, PP = Paneveggio-Pale di San Martino Natural Park, LV = Laghi Valley and GV = Giudicarie Valley) located in the Autonomous Province of Trento (Italian Alps), each characterized by a temporal gradient of re-colonization from east-to-west of wolf in recent years. Specifically, in NV the species is considered stable since 2017, in PP since 2019, in LV since 2021, while yet sporadic in GV. During 2023 in each study area, we collected host-seeking ticks in forested habitats by dragging the vegetation. PCR-based methods were used to detect infection of Borrelia burgorferi s.l., Anaplasma spp. and Babesia spp. in ticks. Results, discussion and conclusion: During this first year, we collected 394 Ixodes spp. ticks across the study areas. We preliminary obtained higher prevalence of Borrelia spp. in areas historically colonized by wolves (NV: 28.72%; PP: 15.48%), compared to where wolf is sporadic (LV: 13.11%; GV: 11.70%) and the opposite for Anaplasma spp. (NV: 1.06%; GV: 4.25%). Babesia spp. prevalence rates did not show any specific pattern. We speculate that the established presence of wolf may interfere differently with the circulation of tick-borne pathogens, both indirectly affecting Borrelia-competent rodent hosts’ predators, such as foxes, or directly by hunting Anaplasma-competent hosts, such as ungulates. These preliminary findings suggest that predator community may have a crucial role in modulating zoonotic disease circulation by affecting preys local presence or abundance that will be incorporated in our forthcoming analysis. The authors acknowledge the support of NBFC to Fondazione Edmund Mach, funded by the Italian Ministry of University and Research, PNRR

Ecological factors associated to the invasion by alien Aedes species in the province of Trento, northern Italy

Aedes albopictus, Ae. koreicus and Ae. japonicus are of increasing public health concerns in Europe. In Trentino province (northern Italy), an established population of Aedes albopictus is reported since late 90’ (1) whilst Ae. koreicus was detected for the first time in 2013 (2). The most recently introduced IMS in our province is Ae. japonicus, recorded in 2022 (Arnoldi D., personal communication). To get an insight into the ecological process affetting IMS abilty to establish into new areas and to obtain a number of parametrs of utility to develop risk maps and predictive mathematical models, we carried out a series of investigation combining filed observation and laboratory experiments. Here we summarise some of the results so far obtained

Cross-taxon congruence between predatory arthropods and plants across Mediterranean agricultural landscapes

Although arthropods are among the most diverse, abundant and ecologically important animals in terrestrial ecosystems, they are generally neglected in most biodiversity inventories due to their complex systematics and overwhelming diversity, coupled with the current decline in the number of taxonomists. For this reason, several surrogate groups for arthropod diversity have been proposed, with plants being identified as a good putative cross-taxon indicator. By sampling plants and three groups of ground-dwelling arthropods (rove beetles, ground beetles and spiders) in 300 sites across 15 landscapes including multiple semi-natural and agricultural habitats, we tested for habitat-dependence and scale-dependence in the cross-taxon congruence. Plant species richness was a poor predictor of the species richness of predatory arthropods. Among the predator groups, ground beetles appeared as the best potential surrogate for the other ground-dwelling predators. This is backed by the fact that ground beetles were extremely diverse and abundant in all habitats and are usually easier to identify than both rove beetles and spiders. Decreasing the scale at which the cross-taxon congruence was tested improved the strength of the cross-taxon congruence. Although plant species richness was not a suitable indicator for the diversity of predatory arthropods, vegetation structure played a significant role in influencing cross-taxon congruence in both natural and agricultural habitats. Our results highlight the need to explore the cross-taxon relationships at a fine habitat resolution scale, as strong correlations were obtained only by taking into account habitat identity