Disentangling Natural From Hunting Mortality in an Intensively Hunted Wild Boar Population

Abstract We assessed age-specific natural mortality (i.e., excluding hunting mortality) and hunting mortality of 1,175 male and 1,076 female wild boar (Sus scrofa) from Chǎteauvillain-Arc en Barrois (eastern France), using a 22-year dataset (1982–2004) and mark-recapture-recovery methods. Overall yearly mortality was >50% for all sex and age-classes. Low survival was mostly due to high hunting mortality; a wild boar had a >40% of chance of being harvested annually, and this risk was as high as 70% for adult males. Natural mortality rates of wild boar were similar for males and females (approx. 0.15). These rates were comparable to rates typical of male ungulates but high for female ungulates. Wild boar survival did not vary across sex and age-classes. Despite high hunting mortality, we did not detect evidence of compensatory mortality. Whereas natural mortality for males was constant over time, female mortality varied annually, independent of fluctuations in mast availability. Female wild boar survival patterns differed from those reported in other ungulates, with high and variable natural mortality. In other ungulates, natural mortality is typically low and stable across a wide range of environmental conditions. These differences may partly reflect high litter sizes for wild boar, which carries high energetic costs. High hunting mortality may induce a high investment of females in reproduction early in life, at the detriment to survival. Despite high hunting mortality, the study population increased. Effective population control of wild boar should target a high harvest rate of piglets and reproductive females.     

Variants of the plasmid pAS8 delta with increased frequency of integration into Rhodopseudomonas sphaeroides chromosome--the result of IS8-element duplication

The possible participation of IS8 and IS elements of Rhodopseudomonas sphaeroides in cointegrate formation by chromosome of the purple bacterium and plasmid pAS8-121 delta has been studied. The plasmid derivatives having deleted Tn7 have been studied. Plasmid integration into the chromosome of the purple bacterium is shown to be mediated by IS8 element of the plasmid. Plasmid derivatives having the integration potential increased for two orders were isolated by a series of intergeneric conjugational crosses during which plasmid pAS8-121 delta was transferred from Rhodopseudomonas sphaeroides (cointegrate of plasmid and chromosome) to Escherichia coli (plasmid in an autonomous state) and back to Rhodopseudomonas sphaeroides. The restriction analysis of plasmid DNA digested by Hpal and Smal restriction endonucleases has revealed the tandem duplications of IS8 in plasmids capable of integration into the chromosome of the purple bacterium with a high frequency.     

Conjugation in Rhodopseudomonas sphaeroides mediated by R plasmids

Plasmids R68.45, RP4, RP4::Mu cts62, RP1ts::Tn10, RP1ts::Tn9, Rts1 and RP41 were transferred into cells of photosynthetic nitrogen-fixation bacterium Rhodopseudomonas sphaeroides from Escherichia coli and Pseudomonas aeruginosa. The transfer of plasmids occurred with high frequency of 10(-1) to 10(-2) per donor cell in all cases. Mobilization of R. sphaeroides 2R chromosome was obtained by RP4 and Rts1 plasmids at a frequency of 10(-7) to 10(-8) per donor cell in all cases. Mobilization of R. sphaeroides 2R chromosome was obtained by RP4 and Rts1 plasmids at a frequency of 10(-7) to 10(-8) per donor cell. Bacteriophage Mu cts62 could be induced from the plasmid DNA in R. sphaeroides 2R cells and was capable of the lytic growth and producing phage progeny. It was demonstrated that an increase in the efficiency of donor chromosomal genes transfer into recipient cells could be achieved in crosses with the donor carrying RP4::Mcts62 plasmid.     

Cloning and identification of an Agrobacterium radiobacter 5D-1 chromosome fragment involved in control of nitrogen metabolism, biosynthesis of indolylacetic acid and replication of ColE1 plasmids

Pleiotropic chromosomal mutations were earlier identified in saprophytic associative bacterium Agrobacterium radiobacter 5D-1. The mutations changed nitrogen metabolism, disturbed synthesis of indolylacetic acid (IAA), and conferred the ability to sustain replication of ColE1 plasmid derivatives, which are not normally maintained in bacteria other than Escherichia. The mutations were designated Nr (Nitrogen metabolism) and assigned to a single cluster on an A. radiobacter genetic map. A 420-bp fragment AGH23.1.1 was cloned from an agrobacterial genomic library. Introduced in the Nr mutants as a part of a pUC18-based recombinant plasmid, the AGH23.1.1 fragment complemented the Nr mutations with respect to nitrogen metabolism and IAA biosynthesis, but transformants still sustained replication of ColE1 plasmids. Transformation with the linear AGH23.1.1 fragment was due to substitution of a mutant allele of the nr gene with its wild-type counterpart as a result of recombination and completely restored the wild type in the Nr mutants, including the inability to maintain ColE1 plasmids. The AGH23.1.1 fragment and its flanking regions were sequenced. The established sequence was shown to contain two open reading frames (ORFs) coding for proteins with unknown functions. Thus, the cloned fragment contained a gene(s) that controls nitrogen metabolism and IAA synthesis and prevent replication of ColE1 plasmids in A. radiobacter cells. Possible variants of the genetic control of these processes are considered.     

Poly(N-vinylformamide)-A drag-reducing polymer for biomedical applications

Water-soluble drag-reducing polymers (DRPs) were previously demonstrated to significantly increase blood flow, tissue perfusion, and tissue oxygenation when injected intravenously at nanomolar concentrations in various animal models. Turbulent flow drag-reducing ability was proven to be the most important factor defining the potential of polymers to favorably affect blood circulation. Several DRPs were applied in previous in vivo tests, but the search continues for suitable DRPs for biomedical applications. We demonstrated that poly(N-vinylformamide) (PNVF) with a molecular weight of 4.5 x 10(6) Da significantly reduced resistance to turbulent flow in a pipe and thus presents a DRP. We also found that the PNVF mechanical degradation is much slower than that of the most commonly used DRP, poly(ethylene oxide). PNVF is known to have low toxicity. Furthermore, our pilot in vivo study showed that PNVF had acceptable biocompatibility and hemodynamic effectiveness and thus could be considered as a DRP candidate for potential clinical use.     

Cloning and Identification of anAgrobacterium radiobacter5D-1 Chromosome Fragment Involved in Controlling Nitrogen Metabolism, Biosynthesis of Indolylacetic Acid, and Replication of ColE1 Plasmids

Pleiotropic chromosomal mutations were earlier identified in saprophytic associative bacterium Agrobacterium radiobacter5D-1. The mutations changed nitrogen metabolism, disturbed synthesis of indolylacetic acid (IAA), and conferred the ability to sustain replication of ColE1 plasmid derivatives, which are not normally maintained in bacteria other than Escherichia.The mutations were designated Nr(Nitrogen metabolism) and assigned to a single cluster on an A. radiobactergenetic map. A 420-bp fragment AGH23.1.1 was cloned from an agrobacterial genomic library. Introduced in the Nr mutants as a part of a pUC18-based recombinant plasmid, the AGH23.1.1 fragment complemented the Nrmutations with respect to nitrogen metabolism and IAA biosynthesis, but transformants still sustained replication of ColE1 plasmids. Transformation with the linear AGH23.1.1 fragment was due to substitution of a mutant allele of the nrgene with its wild-type counterpart as a result of recombination and completely restored the wild phenotype in the Nr mutants, including the inability to maintain ColE1 plasmids. The AGH23.1.1 fragment and its flanking regions were sequenced. The established sequence was shown to contain two open reading frames (ORFs) coding for proteins with unknown functions. Thus, the cloned fragment contained a gene(s) that controls nitrogen metabolism and IAA synthesis and replication of ColE1 plasmids inA. radiobactercells. Possible variants of the genetic control of these processes are considered.