Human-aided dispersal has altered but not erased the phylogeography of the tench

Human-aided dispersal can result in phylogeographic patterns that do not reflect natural historical processes, particularly in species prone to intentional translocations by humans. Here, we use a multiple-gene sequencing approach to assess the effects of human-aided dispersal on phylogeography of the tench Tinca tinca, a widespread Eurasian freshwater fish with a long history in aquaculture. Spatial genetic analysis applied to sequence data from four unlinked loci and 67 geographic localities (38–382 gene copies per locus) defined two groups of populations that were little structured geographically but were significantly differentiated from each other, and it identified locations of major genetic breaks, which were concordant across genes and were driven by distributions of two phylogroups. This pattern most reasonably reflects isolation in two major glacial refugia and subsequent range expansions, with the Eastern and Western phylogroups remaining largely allopatric throughout the tench range. However, this phylogeographic variation was also present in all 17 cultured breeds studied, and some populations at the western edge of the native range contained the Eastern phylogroup. Thus, natural processes have played an important role in structuring tench populations, but human-aided dispersal has also contributed significantly, with the admixed genetic composition of cultured breeds most likely contributing to the introgression

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429):Trypanosoma evansi infections (including Surra)

Abstract Trypanosoma evansi infections (including Surra) have been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on the eligibility of T. evansi infections (including Surra) to be listed, Article 9 for the categorisation of T. evansi infections (including Surra) according to disease prevention and control rules as in Annex IV and Article 8 on the list of animal species related to T. evansi infections (including Surra). The assessment has been performed following a methodology composed of information collection and compilation, expert judgement on each criterion at individual and, if no consensus was reached before, also at collective level. The output is composed of the categorical answer, and for the questions where no consensus was reached, the different supporting views are reported. Details on the methodology used for this assessment are explained in a separate opinion. According to the assessment performed, it is inconclusive whether T. evansi infections (including Surra) can be considered eligible to be listed for Union intervention as laid down in Article 5(3) of the AHL because there was no full consensus on the criterion 5 A(v). Consequently, the assessment on compliance of T. evansi infections (including Surra) with the criteria as in sections 4 and 5 of Annex IV of the AHL, for the application of the disease prevention and control rules referred to in points (d) and (e) of Article 9(1) is also inconclusive, as well as which animal species can be considered to be listed for T. evansi infections (including Surra) according to Article 8(3) of the AHL

Aspects chimiques, enzymatiques et microbiologiques de la dégradation du bois et de ses dérivés aromatiques

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Utilization of waste cellulose - VIII. Enzymatic hydrolysis of spruce bark by cellulases of Trichoderma viride

Native outer, inner and whole bark, and paper mill waste bark have been studied and compared. Extraction with cold and warm water and different chemical pretreatments (H2SO4, NaOH, and NaClO) have been used to improve the accessibility of the cellulose fraction of the substrate to the enzymes and hence to increase the yield of formation of glucose. © 1987 Humana Press Inc.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Formation of polymeric pigments from syringaldehyde in the presence of bacteria. Comparison with chemical oxidative coupling

The formation of polymeric pigments from hydroxy-substituted benzoïc acid in the presence of some strains of Pseudomonas putida was investigated as a possible route to new aromatic polymers. The rate of disappearance of aromatic compounds such as syringaldehyde and its degradation products syringic acid and 3-O-methylgallic acid have been measured. The structure of the pigment has been investigated by GPC, u.v. and FTIR spectroscopy, NMR and elemental analysis. It has been compared with that of the polymeric pigments obtained by chemical oxidative coupling in the absence of bacteria. The bacterial pigments were found to be of badly defined structure different from that of the chemical pigments, and probably similar to humic acids; indeed amino acids are incorporated in the polymer chain. The role of the bacteria at the various steps of the metabolization of the initial aromatic compounds and of pigment formation is discussed. © 1991.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Signature of an early genetic bottleneck in a population of Moroccan sardines (Sardina pilchardus)

Fishery assessment models meant to determine sustainability of commercial marine Wsh failed to predict recent stock collapses due to overexploitation. One Xaw of assessment models is that they strongly rely on catch and age-composition statistics, but largely ignore the genetic background of the studied populations. We examined population genetic structure of sardine (Sardina pilchardus) in the centraleastern and northeastern Atlantic Ocean and Mediterranean Sea to aid Wshery management of this heavily Wshed small pelagic species. We found that sardine has a striking mitochondrial control region, and sequenced a fragment of 387 bp of its 5 -end in 261 individuals collected oV the coasts of Morocco (Dakhla, Tantan, SaW, Larache, and Nador), Portugal (Quarteira), Spain (Pasajes, Barcelona), and Greece (Kavala). High levels of haplotypic diversity rendered a rather unresolved NJ phylogeny. The recovered tree had no phylogeographic structuring except for the clustering of 13 individuals of SaW. In contrast, individuals grouped together according to the presence or absence of a 13-bp insertion in the sequence. ST pairwise comparisons and molecular variance analyses supported genetic diVerentiation between the population of Pasajes (Bay of Biscay), and those of the Mediterranean Sea and Moroccan coast, with a contact zone around the Strait of Gibraltar. This result conWrms the existence of two subspecies, S. pilchardus pilchardus and S. pilchardus sardina that were previously identiWed based on meristics and morphometry. Mismatch distribution analysis showed that sardine populations are expanding since the Pleistocene. Surprisingly, the population of SaW showed strong and statistically signiWcant levels of genetic diVerentiation that could be related with isolation and genetic drift. Comparative analysis of the SaW population versus the rest including mismatch distributions, and a Bayesian skyline plot suggest that the SaW population likely underwent an early genetic bottleneck. The genetic singularity of the SaW population could have been responsible for the historical collapse of this sardine stock in the 1970s.This work received partial Wnancial support from AECI-MAE (Agencia Española de Cooperación Internacional-Ministerio de Asuntos Exteriores) Project No 168/03/P to T.A. and R.Z. L.R. was supported by a Swiss Science Foundation postdoctoral fellowship (823A-061218) and E.G.G. by a MEC (Ministerio de Educación y Ciencia) predoctoral grant.Peer reviewe

Formation of polymeric pigments in the presence of bacteria and comparison with chemical oxidative coupling - II. Catabolism of tyrosine and hydroxyphenylacetic acid by Alcaligenes eutrophus CH34 and mutants

The formation of polymeric pigments using bacteria was investigated to produce new polymers. Polymeric pigments are formed from mutant strains of Alcaligenes eutrophus which are not able to open the aromatic ring (tyu-) but transform tyrosine into p-hydroxyphenylacetic acid. This compound is then hydroxylated into homogentisic acid which undergoes oxidative coupling into polymeric pigments. Another carbon source is required to allow bacterial growth. The rate of disappearance of the initial product (either tyrosine or p-hydroxyphenylacetic acid) and the rate of formation and disappearance of intermediates were studied by ultraviolet (UV) absorption spectroscopy and high-performance liquid chromatography (HPLC). Pigment formation was monitored by gel permeation chromatography (GPC). The pigment was isolated and characterized by UV and infrared (IR) absorption spectroscopy, nuclear magnetic resonance (NMR) and elemental analysis. It was shown to have a complex structure involving aromatic and aliphatic saturated and unsaturated structures. Nitrogen is incorporated by condensation with amino acids and other nitrogen-containing molecules excreted by the bacteria. For comparative purposes, chemical oxidative coupling of homogentisic acid in the absence of bacteria was performed at pH 8.5 and 11.5 in the presence of oxygen. A badly defined but different mixed aliphatic-aromatic structure was isolated. The role of the bacteria in the different steps of transformation of the initial product is discussed. Copyright © 1996 Elsevier Science Ltd.SCOPUS: ar.jinfo:eu-repo/semantics/publishe