Soil humic substances stimulate proton release by intact oat seedling roots

The effect of a soil humic fraction (HS) on proton extrusion into deionized water by intact oat seedling roots was studied. In the presence of HS, at concentration of 10 μg organic carbon (C) mL^‐1, a clear stimulation of acidification of the outer medium by the roots was observed after three to four hours of incubation. The addition of 0.5 mM vanadate to the solution bathing the roots drastically reduced the net proton extrusion, either in the presence or absence of HS, suggesting the involvement of the plasma membrane H⁺‐ATPase in the stimulation of the acidification of the outer medium by oat roots. The release of potassium (K) from the roots into deionized water was also monitored concomitantly to the proton extrusion. The loss of endogenous K from the roots was similar in the presence or absence of HS, while the recovery of the cation was slower in the presence of the humic fraction. However, after reabsorption of the released K, no net acidification was observed in control roots, while HS‐treated roots significantly decreased the pH of the deionized water. The addition of 3 mM K to the external medium greatly enhanced the proton release from roots, while the presence of humic substances reduced the magnitude of the stimulation by K. When K was supplied at a concentration closer to that encountered in the soil (<0.1 mM), HS significantly stimulated proton release. The effect of HS on root extracellular acidification supports the idea of a role of soil humic substances on plant nutrition via interaction with cell membrane functions.     

Anaplasma phagocytophilum in horses and ticks: a preliminary survey of Central Italy

Anaplasma phagocytophilum, the causative agent of granulocytic ehrlichiosis, affects several species of wild and domesticated mammals, including horses. In this work we compared direct and indirect methods to evaluate A. phagocytophilum presence in Central Italy: 135 sera were screened by IFA for A. phagocytophilum and other haemopathogens (Theileria equi and Babesia caballi). Each horse was also tested for A. phagocytophilum 16S rRNA with a nested-PCR technique. In order to examine the risk of A. phagocytophilum transmission, 114 ticks were examined for the presence of A. phagocytophilum by PCR targeting the 16S rRNA. The seroprevalence against A. phagocytophilum was 17.03% and 11 horses (8.14%) showed positive PCR results. The concordance rate of A. phagocytophilum detection between IFAT and PCR had a K value of 0.34.     

Canine fertility: The consequences of selection for special traits

Pedigree dogs and cats are bred aiming to conform breed standards with very poor consideration for breeding stock fertility. At the same time, the genetic asset underlining reproductive traits could be effectively analysed like in other species under selection. The definition of selection targets is very important in breeding protocols determination. The aim of the present work is to present an overview of the different correlations between reproduction and genetics, starting from selection procedure and inbreeding coefficient moving to genomic and the application of SNPs and GWAS on population study and identification of genes involved in phenotypical variation of reproductive traits in dogs. Particular relevance has been given to the concept of inbreeding which effects on canine reproduction have been presented. The use of genomic information in inbreeding coefficient calculation can be considered an improved effective procedure in the evaluation of the genetic variability loss in canine population and its negative effects on reproductive traits.     

Heritability and genetic correlations between rumination time and production traits in Holstein dairy cows during different lactation phases

So far, rumination has been used as a proxy for monitoring dairy cow health at farm level. However, investigating its genetic aspects as well as its correlation with other important productive traits may turn this management tool into a new informative selection criterion. However, scientific evidences on genetic correlation among rumination time (RT) and milk production and milk composition are still scarce. Therefore, the objective of this study was to estimate the heritability of RT across three lactation phases and its genetic correlation with milk production, milk composition and somatic cell count (SCC). Results of our study showed that heritability for RT was 0.34 and was constant across lactation. The mean genetic correlations between RT and milk production and composition traits were 0.07 (milk production), ?0.07 (protein yield), ?0.31 (fat yield), and ?0.32 (fat/protein ratio). The mean genetic correlation between RT and the SCC was 0.05.     

Extractable iron and organic matter in the suspended insoluble material of fog droplets

In this work the formation and composition of aggregates between metals and organic material is studied in real fog samples. In a preliminary experiment it has been found that concentrated cloud samples form a yellow-brown precipitate in the presence of Fe(III). Standards of humic acids and fulvic acids co-precipitate with Fe(III), forming similar aggregates i.e. iron-humates (Fe-HA) and iron-fulvates (Fe-FA). By comparing the solubility properties of aggregates by extracting organic carbon (OC) in different pH conditions, it has been observed that fog droplet particulate samples are characterised by solubility properties more similar to those of Fe-HA than Fe-FA. Dilute alkaline solutions can also easily extract organic refractory substances that form aggregates with metals. The recoveries of the total extractable organic matter (accounting for 12% of total insoluble carbon and 15% of particulate mass) are similar to those of humic-like substances (HULIS) from particulate samples. The chromatographic behaviour and functional group characteristics measured in the alkali-extract fraction of precipitated aggregates with iron and in the insoluble particulate of fog samples, are those of humic-like material. Thus, soluble HULIS are able to interact with iron to form particulate, but the composition of a large fraction of insoluble organic carbon is still unknown. These findings have implications on the solubility and surface tension properties of fog droplets and can therefore potentially influence droplet formation, as well as cloud chemical and photochemical processes.     

First attempts towards the restoration of gorgonian populations on the Mediterranean continental shelf

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