Evaluation of risk and vulnerability using a Disease Flow Centrality measure in dynamic cattle trade networks

A new method for the calculation of a centrality measure (Disease Flow Centrality, DFC), which takes into account temporal dynamics of livestock movement networks, is proposed. The method is based on a network traversal algorithm which represents an epidemic process more realistically compared with traditional graph traversal algorithms used in the calculation of centrality measures on static networks. The new approach was tested on networks generated from all the registered movements of cattle in Italy in the years 2007, 2008 and 2009 and the results were compared to those obtained by classical centrality measures. The results show that DFC values often differ substantially from those of other centrality measures and that these DFC values tend to be more unstable in time. The DFC offers several advantages for assessing risk and vulnerability of specific holdings and of an entire network, using recent movement data from national livestock databases. Some examples also indicate how the basic approach in the DFC calculation could be expanded into a more complex epidemic model by incorporating weights and how it could be combined with a geo-spatial perspective.     

Selection of sourdough lactobacilli with antifungal activity for use as biopreservatives in bakery products

Two hundred and sixteen LAB cultures from sourdoughs and dough for bread and panettone production were screened for in vitro antifungal properties against three indicator cultures ascribed to Aspergillus japonicus , Eurotium repens , and Penicillium roseopurpureum , isolated from bakery environment and moldy panettone. Nineteen preselected isolates were subjected to minimum inhibitory concentration determination against the indicator cultures. Sourdoughs prepared with the two most promising strains, identified as Lactobacillus rossiae LD108 and Lactobacillus paralimentarius PB127, were characterized. The sourdough extracts were subjected to HPLC analysis coupled with a microtiter plate bioassay against A. japonicus to identify the active fractions. MALDI-TOF MS analysis revealed the occurrence of a series of peptides corresponding to wheat α-gliadin proteolysis fragments in the active fraction from L. rossiae LD108 sourdough. The ability to prevent mold growth on bread was demonstrated for both strains, whereas L. rossiae LD108 also inhibited mold growth on panettone.     

Traceability of inbred and crossbred Cinta Senese pigs by evaluating the oxidative stress

Previous studies on the oxidative stress in swine indicated a strong link between the values of reactive oxygen metabolites (ROMs), the subsequent antioxidant adaptive response (OXY) and the genetic selection. Such findings, mainly related to a cardiovascular inadequacy in lean, large muscle blocks and fast growing breeds, is associated with specific metabolic diseases such as porcine stress syndrome and mulberry heart disease. In this study, we investigated the oxidative stress parameters to trace the genetics of Cinta Senese (CS) pigs, a historical breed free-range reared in Siena countryside. Sera from CS (n = 24) and Large White x CS (LW x CS) (n = 24) groups around 120 kg body weight fed the same diet were sampled at slaughter. Sera from wild boars (WB) (n = 24) hunted in the same district were also considered. ROMs and OXY were evaluated in the three groups of swine. Significant differences by one-way anova (P < 0.05) between groups were found for both procedures. ROM levels were lower in WB (9.79 +/- 5.76 mm H2O2) and CS (18.02 +/- 7.42 mm H2O2), and highest in LW x CS (42.78 +/- 8.61 mm H2O2). OXY values ranged from 271.37 +/- 50.90 microm neutralized HOCl (WB) to 343.21 +/- 57.45 microm neutralized HOCl (LW x CS). Results indicated that the evaluation of the oxidative stress can effectively trace the CS pigs, thus aiding in preserving the overall specific traits of such a historical animal.     

Replacing methyl bromide in annual strawberry production with glucosinolate-containing green manure crops

The use of biocidal green manure crops is an agronomic technique for amending soil with fresh organic matter containing volatile compounds active in controlling some soil-borne pests and diseases. Two new selections of the Brassicaceae family were cultivated, incorporated before planting strawberries and tested as an alternative to fumigation with methyl bromide. Two biocidal green manure crops (Brassica juncea L sel ISCI20, Eruca sativa Mill cv Nemat) containing glucosinolate-myrosinase systems, a conventional green manure (barley), untreated soil and a fumigated control were evaluated during two seasons. The effect of these soil management systems on subsequent strawberry performance was evaluated by monitoring yield and plant growth parameters. In both years, biocidal plant green manure treatments led to a fruit yield lower than with methyl bromide, but higher than with conventional green manure or untreated soil. These results confirm the good prospects for biocidal green manures, not only as an environmentally friendly alternative to methyl bromide in conventional agriculture, but also in organic agriculture as an alternative to conventional green manure crops.     

Inappropriate feeding practice favors the transmission of Trichinella papuae from wild pigs to saltwater crocodiles in Papua New Guinea

The recent discovery of Trichinella zimbabwensis in farmed crocodiles (Crocodilus niloticus) of Zimbabwe and its ability to infect mammals, and the development of both T. zimbabwensis and Trichinella papuae in experimentally infected reptiles led to an investigation of Trichinella infection in saltwater crocodiles (Crocodylus porosus) and in wild pigs (Sus scrofa) of Papua New Guinea, to see if T. papuae also, is present in both cold- and warm-blooded animals. Of 222 crocodiles examined, 47 animals (21.2%), all from Kikori, Gulf Province, were positive for non-encapsulated larvae in the muscles. The greatest number of larvae was found usually in the biceps, with an average of 7 larvae/g. One isolate from a crocodile infected successfully both laboratory rats and mice. Of 81 wild pigs examined, 9 from Bensbach river area (Western Province) and 1 from Kikori area (Gulf Province) were positive for non-encapsulated larvae in the muscles. Trichinella larvae from both saltwater crocodiles and wild pigs have been identified by multiplex-PCR analysis as T. papuae. The sequence analysis of the region within the large subunit ribosomal DNA, known as the expansion segment V, has shown the presence of a molecular marker distinguishing T. papuae isolates of Bensbach river area from those of Kikori area. This marker could be useful to trace back the geographical origin of the infected animal. The epidemiological investigation carried out in the Kikori area has shown that local people catch young crocodiles in the wild and keep them in holding pens for several months, before sending them to the crocodile farm in Lae (Morobe Province). They feed the crocodiles primarily with wild pig meat bought at the local market and also with fish. These results stress the importance of using artificial digestion for routinely screening of swine and crocodiles, and of adopting measures for preventing the spread of infection, such as the proper disposal of carcasses and the adequate freezing of meat.     

Combined approaches to identify genomic regions involved in phenotypic differentiation between low divergent breeds: Application in Sardinian sheep populations

Selective breeding has led to modifications in the genome of many livestock breeds. In this study, we identified the genomic regions that may explain some of the phenotypic differences between two closely related breeds from Sardinia. A total of 44 animals, 20 Sardinian Ancestral Black (SAB) and 24 Sardinian White (SW), were genotyped using the Illumina Ovine 50K array. A total of 68, 38 and 15 significant markers were identified using the case–control genome‐wide association study (GWAS), the Bayesian population differentiation analysis (F_ST) and the Rsb metric, respectively. Comparisons among the approaches revealed a total of 22 overlapping markers between GWAS and F_ST and one marker between GWAS and Rsb. Three markers detected by Rsb were also located near (<2 Mb) to highly significant regions identified by GWAS and F_ST analyses. Moreover, one candidate marker identified by GWAS and F_ST approaches was located in a run of homozygosity island that was shared by both breeds. We identified several genes involved in many phenotypic differences (such as stature and growth, reproduction, ear size, coat colour, behaviour) between the two analysed breeds. This study shows that combining several genome‐wide approaches could improve discovery of regions involved in the variability of breeding traits and responsible for the phenotypic diversity even between closely related breeds. Overall, the combination of such genome‐wide methods can be extended to other livestock breeds that share between them a similar genetic background, to understand the process that shapes the patterns of genetic variability between closely related populations.     

Detection of a Phytoplasma Associated with Grapevine Flavescence dorée in Clematis vitalba

About 40 different species of wild herbaceous and woody plants were collected in underbrush close to a vineyard where Flavescence dorée (FD) has been reported for several years. Polymerase chain reaction assays were carried out using DNA extracted from leaves of each species for the detection of the presence of phytoplasmas. Only samples of Clematis vitalba were found to be infected with phytoplasmas. Restriction fragment length polymorphism and sequencing data of the 16S ribosomal RNA gene and of a non-ribosomal DNA fragment FD9 revealed that the phytoplasma isolate was identical to that causing FD in the nearby vineyard. The isolate identified in the clematis is the same as the FD-C phytoplasma found in grapevine in north-east Italy.     

Plant response to biowaste soluble hydrolysates in hibiscus grown under limiting nutrient availability

Biostimulants are substances promoting plant growth, quality and stress resistance. The present work aimed to investigate whether soluble hydrolysates from biowaste performed as biostimulants. Hibiscus (Hibiscus moscheutos L. subsp. palustris) plants were subjected to four treatments: standard fertilization, low fertilization (LF), and LF with added soluble digestate or soluble compost. Plant performance indicators were biomass accumulation, biometric parameters, leaf gaseous exchanges and elemental composition, and nitrogen (N)-use efficiency. LF negatively affected most of the investigated parameters. However, plants treated with biowaste-derived products performed better than untreated low-fertilized plants (+21 to 145% for biomass accumulation and biometric parameters, and carbon assimilation rate) and for many parameters reached values comparable to those showed by standard-fertilized plants or even higher, as in the case of Potassium (K), Silicon (Si), and Molybdenum (Mo) leaf content, and N use efficiency. Therefore, the tested soluble hydrolysates demonstrated to have biostimulant properties in hibiscus grown under nutritional stress.     

Tannin-caprolactam and Tannin-PEG formulations as outdoor wood preservatives: weathering properties

Key message

This article presents the leaching, fire and weathering resistance improvements of samples treated with tannin-based wood preservatives added of caprolactam. PEG-added formulations show limited applicability. The FT-IR and ¹³ C-NMR analyses of the caprolactam-added formulations show some evidences of copolymerization.

Context

Tannin-boron wood preservatives are known for their high resistance against leaching, biological attacks, fire as well as for the good mechanical properties that they impart to wood. These properties promoted these formulations for being a candidate for the protection of green buildings. However, the low elasticity of these polymers and their dark colour implied limited weathering resistances.

Aims

The aim of the study is to find suitable additives for tannin-based formulations to overcome their limited weathering resistances, without compromising the other properties.

Methods

Treatment, leaching and fire tests, dimensional stability as well as artificial and natural weathering of the timber treated with caprolactam-added and PEG-added formulations were performed. FT-IR and ¹³C-NMR of the formulations were presented.

Results

The presence of caprolactam improved the properties of the formulation with particularly significant results in terms of resistance against leaching and dimensional stability. These enhancements were imparted also to the weathering resistance of the tannin-caprolactam formulations. Indeed, the colour changes during the artificial and natural exposures were stable for longer periods. FT-IR and ¹³C-NMR investigations of the advanced formulations were led, and covalent copolymerization of the caprolactam with the tannin-hexamine polymer was observed.

Conclusion

The tannin formulations with caprolactam improved the durability of the wood specimens, while the PEG-tannin presented strong application drawbacks.