Effect of the supplementation of vitamins and organic minerals on the performance of broilers under heat stress

The objective of this experiment was to evaluate the effect of diet supplementation with vitamins C and E and organic minerals Zn and Se on the performance of 1 to 35 day-old broilers from, kept under cyclic heat stress (25 to 32ºC). Four levels of vitamin-mineral supplementation were used (T1-control diet (60/30 IU of vit E for starter and growing diet, respectively, zero vit. C, 80 ppm of inorganic Zn, 0.3 ppm of inorganic Se); T2-control diet + 100 UI vit E and 300 ppm vit C/kg; T3-control diet + 40 ppm Zn and 0,3 ppm Se/kg; T4-control diet + T2 and T3 levels) and two environments - thermoneutral and cyclic heat stress (TN and HS) from 14 to 35 days of age. In the period when part of the birds was submitted to HS, from 14 to 35 days, it was observed lower feed intake (FI) and better feed conversion (FC) for HS birds receiving supplementation compared to the group without supplementation. Evaluating the total period, all the types of supplementation provided lower FI and better FC than the control treatment, but not affected weight gain (WG). The supplementation of vitamins C and E and/or organic minerals Zn and Se improved the performance of birds due to a lower FI resulting in better FC, independently on the environment

Quantitative Hydrogeology of Volcanic Lakes: Examples from the Central Italy Volcanic Lake District

Volcanic lakes are surface expressions of the hydrogeology of volcanic complexes. Hydrogeological analysis of volcanic complexes is important both in terms of management of the water resource and from the point of view of associated geothermal and volcanic processes. In particular volcanic lakes are the site of possible mixing between superficial fluids (water) and endogenous fluids (gas and/or magma). The Tyrrhenian volcanic domain hosts several volcanic lakes, which, depending on their origin, can be classed as crater lakes or caldera lakes. The presence of large cities (like Rome), and intense industrial and agricultural activities have significantly modified the “natural” equilibrium and groundwater resources have been significantly depleted during the last 20–30 years. In many areas the situation has turned “critical”, involving both the lowering of groundwater and lake levels. In this chapter, we present the results of quantitative hydrogeological analysis of two volcanic lakes in the surroundings of the densely urbanized hinterland of Roma capital city (Italy): the Bracciano caldera lake basin (Sabatini volcanic complex) and the Albano crater lake basin (Colli Albani volcano). The groundwater flow systems have been analyzed and the hydrogeological water balances defined. A focus has been put on the areas with larger aquifer depletion. The methodologies applied to the lake water balances include GIS analyses supported by geostatistics