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121.
Terio KA Kinsel MJ Raphael J Mlengeya T Lipende I Kirchhoff CA Gilagiza B Wilson ML Kamenya S Estes JD Keele BF Rudicell RS Liu W Patton S Collins A Hahn BH Travis DA Lonsdorf EV 《Journal of zoo and wildlife medicine》2011,42(4):597-607
During a population decline or disease outbreak, the true risk of specific diseases to a wild population is often difficult to determine because of a lack of baseline disease information. To better understand the risk of disease in an endangered and scientifically important population of chimpanzees (Pan trogylodytes schweinfurthii), a health monitoring program was initiated in Gombe National Park, Tanzania. As part of this health monitoring program, comprehensive necropsies with histopathology were conducted on chimpanzees (n = 11; 5 male, 6 female), ranging in age from fetal to 44 yr, that were found dead between August 2004 and January 2010. In contrast to previous reports, respiratory disease was not noted as a cause of morbidity or mortality. Trauma was the most common cause of death in these 11 chimpanzees. All of the chimpanzees greater than 1 yr of age had intestinal and mesenteric parasitic granulomas associated with true strongyles consistent with Oesophagostomum spp. The relative numbers of granulomas increased with age and, in some cases, may have been a cause of weight loss and diarrhea. Simian immunodeficiency virus (SIV)cpz infection was documented in four deceased apes, all of whom exhibited varying amounts of lymphoid depletion including two females with marked CD4+ T cell loss consistent with endstage SIVmac or human immunodeficiency virus infections. Myocardial megalokaryosis was common in chimpanzees greater than 1 mo of age; yet myocardial interstitial fibrosis, a common lesion in captive chimpanzees, was uncommon and only noted in two aged chimpanzees. These findings provide important information on causes of morbidity and mortality in wild chimpanzees, information that can be used to interpret findings during population declines and lead to better management of this population in the context of disease risk. 相似文献
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Crissiuma A Favacho A Gershony L Mendes-de-Almeida F Gomes R Mares-Guia A Rozental T Barreira J Lemos E Labarthe N 《Journal of Feline Medicine and Surgery》2011,13(2):149-151
The prevalence of Bartonella species DNA and antibodies for Bartonella henselae were studied in 40 clinically healthy cats (Felis catus, Linnaeus 1758) submitted to a spay/neuter program in Rio de Janeiro, Brazil. Additionally, the prevalence of Bartonella species DNA was investigated in the fleas found parasitizing the subject cats. For this purpose, blood samples were obtained from all cats, and DNA extraction was performed on the blood, and blood clotted samples, as well as on pools of fleas obtained from them. Antibodies for B henselae were detected on serum samples. Bartonella species DNA was detected in 17 cats, whereas serum reactivity for B henselae was found in 19. A total of 20 cats were flea-infested and nine of these 20 had Bartonella species DNA in their blood. In four of the 20 flea-infested cats, Bartonella species DNA was detected in the fleas obtained from those cats, but only one of these four cats had Bartonella species DNA in its blood. 相似文献
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Novotny et al. (Reports, 25 August 2006, p. 1115) argued that higher herbivore diversity in tropical forests results from greater phylogenetic diversity of host plants, not from higher host specificity. However, if host specificity is related to host abundance, differences in relative host abundance between tropical and temperate regions may limit any general conclusion that herbivore diversity scales directly with host-plant diversity. 相似文献
125.
Antonio Ramis Geert van Amerongen Marco van de Bildt Loneke Leijten Raphael Vanderstichel Albert Osterhaus Thijs Kuiken 《Veterinary research》2014,45(1)
Historically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental HPAIV H5N1 infection of black-headed gulls (Chroicocephalus ridibundus) to determine their susceptibility to infection and disease from this virus, pattern of viral shedding, clinical signs, pathological changes and viral tissue distribution. We inoculated sixteen black-headed gulls with 1 × 104 median tissue culture infectious dose HPAIV H5N1 (A/turkey/Turkey/1/2005) intratracheally and intraesophageally. Birds were monitored daily until 12 days post inoculation (dpi). Oropharyngeal and cloacal swabs were collected daily to detect viral shedding. Necropsies from birds were performed at 2, 4, 5, 6, 7, and 12 dpi. Sampling from selected tissues was done for histopathology, immunohistochemical detection of viral antigen, PCR, and viral isolation. Our study shows that all inoculated birds were productively infected, developed systemic disease, and had a high morbidity and mortality rate. Virus was detected mainly in the respiratory tract on the first days after inoculation, and then concentrated more in pancreas and central nervous system from 4 dpi onwards. Birds shed infectious virus until 7 dpi from the pharynx and 6 dpi from the cloaca. We conclude that black-headed gulls are highly susceptible to disease with a high mortality rate and are thus more likely to act as sentinel species for the presence of the virus than as long-distance carriers of the virus to new geographical areas.
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-014-0084-9) contains supplementary material, which is available to authorized users. 相似文献126.
ER da Cunha CF Martins CG Silva HC Bessler SN Báo 《Reproduction in domestic animals》2014,49(5):806-812
The objective of this work was to study cellular types that did not participated in the gastrulation process, amniotic fluid cells (AFCs) and umbilical cord cells (UCCs), in conditions of long‐term culture and cryopreserved with different solutions. The AFCs and UCCs were used in a comparative study with ear fibroblast cells (EFCs) that were cultured in vitro until 20 cellular passages and cryopreserved in 10% dimethylsulphoxide (DMSO), 5% dimethyl formamide (DMF) and 7% glycerol (Gly) solutions. The cellular viability, ultrastructure, DNA fragmentation and chromosome stability were evaluated to determine the cellular type most resistant. In all cell types, it was possible to evaluate the AFCs until 15 passages and UCCs until 20 passages with different periods of cellular growth to reach the confluence phase. Solutions containing 10% DMSO ensured viability of 90.33 ± 5.58%, 90.56 ± 4.40% and 81.90 ± 3.31%, respectively for EFCs, AFCs and UCCs, being significantly more efficient and with less variation than other cryoprotectant solutions. The AFCs were more sensitive to cryopreservation and presented low viability rate at the passage 20 (17.2 ± 8.87%). There was no change in karyotype and nuclear fragmentation was low in all cellular passages studied. With the scanning electron analysis was possible the characterization of AFCs and UCCs in suspension. The three cellular types of cells presented different shapes and characteristics on the surface. The results demonstrate that bovine AFCs and UCCs can be isolated, cultured in vitro and cryopreserved in 10% DMSO, not causing damage to DNA and chromosomes. The UCCs were more resistant than AFCs in all aspects. 相似文献
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Comparison of ecological condition and conservation status of English yew population in two Austrian gene conservation forests 总被引:1,自引:0,他引:1
DHAR Amalesh RUPRECHT Herwig KLUMPP Raphael VACIK Harald 《林业研究》2007,18(3):181-186
English yew Taxus baccata L. has been catalogued as endangered tree species and prone to extinction in Austria as well as many other parts of Europe. The present work is based on the comparison of the natural population of two gene conservation forests from different geographic locations in Austria where the spatial structure, regeneration status and possible conservation measures are examined. The pole stand distribution varied distinctly in each sites. The total no of individuals per ha (DBH ≥5 cm), average DBH and average height were 492 n.hm^-2, 8.8 cm and 6.3 m in Stiwollgraben whereas in Leininger Riese 45 n.hm^-2, 16.3 cm and 7.6 m respectively. Over 79% of the Stiwollgraben population were represented the good health condition, while in Leininger Riese it was less then 49 % which means population of Stiwollgraben is in better condition compared to Leininger Riese. The sites differed considerably in the pattern of regeneration but pattern were consistent with the dynamics depicted by the age distribution. Considering the one-year-old seedlings Stiwollgraben contains 13 019 individuals.hm^-2 whereas Leininger Riese only 1 368. Surprisingly there were no any saplings in respect of 51 to 150 cm height classes in both sites and 30 to 50 cm in Stiwollgraben. In that context the conservation of English yew on the forest level may require well-managed reserves and long-term rotations between harvest events, protection from the herbivore and reduction of competition, which will enhance the long-term viability of the species. 相似文献