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Samuel M.D.,U.S. Geological Survey | Hall J.S.,U.S. Geological Survey | Brown J.D.,University of Georgia | Brown J.D.,Pennsylvania State University | And 3 more authors.
Ecological Applications

Wild water birds are the natural reservoir for low-pathogenic avian influenza viruses (AIV). However, our ability to investigate the epizootiology of AIV in these migratory populations is challenging and, despite intensive worldwide surveillance, remains poorly understood. We conducted a cross-sectional, retrospective analysis in Pacific Flyway Lesser Snow Geese, Chen caerulescens, to investigate AIV serology and infection patterns. We collected nearly 3000 sera samples from Snow Geese at two breeding colonies in Russia and Canada during 1993-1996 and swab samples from .4000 birds at wintering and migration areas in the United States during 2006-2011. We found seroprevalence and annual seroconversion varied considerably among years. Seroconversion and infection rates also differed between Snow Goose breeding colonies and wintering areas, suggesting that AIV exposure in this gregarious waterfowl species is likely occurring during several phases (migration, wintering, and potentially breeding areas) of the annual cycle. We estimated AIV antibody persistence was longer (14 months) in female geese compared to males (6 months). This relatively long period of AIV antibody persistence suggests that subtype-specific serology may be an effective tool for detection of exposure to subtypes associated with highly pathogenic AIV. Our study provides further evidence of high seroprevalence in Arctic goose populations, and estimates of annual AIV seroconversion and antibody persistence for North American waterfowl. We suggest future AIV studies include serology to help elucidate the epizootiological dynamics of AIV in wild bird populations. © 2015 by the Ecological Society of America. Source

Abaturov B.D.,RAS Severtsov Institute of Ecology | Subbotin A.E.,All Russia Research Institute of Nature Conservation
Russian Journal of Theriology

Levels of digestibility and protein content necessary for maintenance, weight gain and lactation were estimated for Saiga antelope (Saiga tatarica). Estimates were based on results of digestion-balance trials using confined animals, and feeding trials involving tractable animals at pasture. Threshold parameters were estimated by regression of metabolizable energy intake and body weight gain, food digestibility and metabolic energy intake, protein content in food and the amount of consumed digestible protein. To meet maintenance requirements, food digestibility must be > 59%, with protein content > 7.7%. To meet requirements for growth and lactation, minimum digestibility must be 61-68%, with protein content > 14%. When feeding on native semi-desert range, free-ranging Saiga antelope can meet these nutritional thresholds only through selective foraging. Therefore, when evaluating grazing capacity of Saiga habitat it is important to take into consideration that only a small portion of the total plant biomass is comprised of plants and plant parts of sufficient quality. © RUssian Journal Of Theriology, 2011. Source

Dibrova A.K.,All Russia Research Institute of Nature Conservation | Khanchich O.A.,Moscow State University
Polymer Science - Series A

Preparation conditions and properties of cellulose solutions in DMAA containing 7-8% lithium chloride are considered. Investigation of the optical anisotropy and structure of cellulose solutions in this solvent confirms that the LS state is attained with an increase in the concentration of cellulose. On the basis of these cellulose solutions, fibers not ranking below viscose fibers in mechanical properties are prepared. The use of a mixed solution of 95% cellulose and 5% poly(amidobenzimidazole) in DMAA containing 7% lithium chloride makes it possible to prepare films and fibers whose strength is more than two times greater than the strength of cellulose hydrate fibers. The deformation-driven orientation and supramolecular structure of fibers and films are studied by spectroscopy and small-angle scattering of polarized light. © 2010 Pleiades Publishing, Ltd. Source

Ebbinge B.S.,Wageningen University | Prokosch P.,GRID Arendal | Spaans B.,Netherlands Institute for Sea Research | Muskens G.J.D.M.,Wageningen University | And 3 more authors.

The distribution of Dark-bellied Brent Geese Branta b. bernicla moulting on the Taimyr Peninsula, in the Russian arctic, varies between years depending on whether the birds had a successful breeding season. Counts made of moulting flocks show that major shifts in numbers occur, particularly in non-breeding years, when in line with Salomonsen's (1968) hypothesis a higher proportion of the population moults further north. For instance, the delta of the Lower Taimyr River in the northern part of the Taimyr Peninsula held 10-times more moulting Dark-bellied Brent Geese in 1989, a non-breeding year, than it did in the good 1990 breeding season. At a more local scale, in good breeding years family groups with small goslings tend to move away from breeding islands in the Pyasina Delta, western Taimyr, to avoid gosling predation by Taimyr Gulls Larus taimyrensis which nest in colonies on the same islands, whereas in poor breeding years adult geese concentrate on these same islands to moult and avoid the mainland sites used for moulting in good breeding years. Failed breeders have greater freedom than parent birds to choose where to moult as successful breeders remain with their goslings to protect and guide them to the safest nursery and moult areas. Re-captures of ringed Darkbellied Brent Geese at a moulting site in the Pyasina Delta found that, in poor breeding years, up to one-fifth the birds had moulted at the site previously, but that the majority of ringed birds known to be still alive were not site-faithful to their moulting grounds. © Wildfowl and Wetlands Trust. Source

Savinov V.,Akvaplan Niva | Muir D.C.G.,Environment Canada | Svetochev V.,RAS Murmansk Marine Biological Institute | Svetocheva O.,RAS Murmansk Marine Biological Institute | And 6 more authors.
Science of the Total Environment

Organochlorine compounds total DDT (ΣDDT), total HCH isomers (ΣHCH), toxaphenes (sum of Parlar 26, 50, 62), mirex, endrin, methoxychlor, total chlorinated benzenes (ΣCBz), total chlordane compounds (ΣCHL), polychlorinated biphenyls (total of 56 congeners; ΣPCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), and polybrominated diphenyl ethers (sum of 7 tri- to hepta congeners; ΣPBDEs) were analysed in the blubber of adult ringed seals from the four areas of the Russian Arctic (White Sea, Barents Sea, Kara Sea and Chukchi Sea) collected in 2001-2005. Ringed seals from the south-western part of the Kara Sea (Dikson Island - Yenisei estuary) were the most contaminated with ΣDDTs, ΣPCBs, ΣCHL, and mirex as compared with those found in the other three areas of Russian Arctic, while the highest mean concentrations of ΣHCHs and PCDD/Fs were found in the blubber of ringed seals from the Chukchi Sea and the White Sea, respectively. Among all organochlorine compounds measured in ringed seals from the European part of the Russian Arctic, concentrations of ΣDDT and ΣPCBs only were higher as compared with the other Arctic regions. Levels of all other organochlorine compounds were similar or lower than in seals from Svalbard, Alaska, the Canadian Arctic and Greenland. ΣPBDEs were found in all ringed seal samples analysed. There were no significant differences between ΣPBDE concentrations found in the blubber of ringed seals from the three studied areas of the European part of the Russian Arctic, while PBDE contamination level in ringed seals from the Chukchi Sea was 30-50 times lower. ΣPBDE levels in the blubber of seals from the European part of the Russian Arctic are slightly higher than in ringed seals from the Canadian Arctic, Alaska, and western Greenland but lower compared to ringed seals from Svalbard and eastern Greenland. © 2011 Elsevier B.V. Source

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