The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Junwei Wang - One of the best experts on this subject based on the ideXlab platform.
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Comparative liver transcriptome analysis in Ducklings infected with duck hepatitis A virus 3 (DHAV-3) at 12 and 48 hours post-infection through RNA-seq
Veterinary Research, 2018Co-Authors: Xuelian Zhang, Chong Cao, Yue Liu, Wenjing Zhang, Chunxue Hao, Haotian Chen, Qi Zhang, Wenlong Zhang, Mingchun Gao, Junwei WangAbstract:AbstractDuck hepatitis A virus 3 (DHAV-3), the only member of the novel genus Avihepatovirus, in the family Picornaviridae, can cause significant economic losses for duck farms in China. Reports on the pathogenicity and the antiviral molecular mechanisms of the lethal DHAV-3 strain in Ducklings are inadequate and remain poorly understood. We conducted global gene expression profiling and screened differentially expressed genes (DEG) of duckling liver tissues infected with lethal DHAV-3. There were 1643 DEG and 8979 DEG when compared with mock Ducklings at 12 hours post-infection (hpi) and at 48 hpi, respectively. Gene pathway analysis of DEG highlighted mainly biological processes involved in metabolic pathways, host immune responses, and viral invasion. The results may provide valuable information for us to explore the pathogenicity of the virulent DHAV-3 strain and to improve our understanding of host–virus interactions.
Robert G. Clark - One of the best experts on this subject based on the ideXlab platform.
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landscape level correlates of mallard duckling survival implications for conservation programs
Journal of Wildlife Management, 2012Co-Authors: Pauline M Bloom, Robert G. Clark, David W Howerter, Llwellyn M ArmstrongAbstract:Despite recent work, uncertainty remains concerning how abiotic and biotic factors affect duckling survival. Additionally, upland habitat characteristics may affect duckling survival rates but this potential relationship has largely been ignored. We evaluated several unresolved hypotheses about causes of mallard (Anas platyrhynchos) duckling survival variation, with an emphasis on assessing effects of managed and remnant natural upland habitats. During 1993–2000, 617 radio-marked females provided information about brood habitat use and duckling survival on 27 sites in prairie Canada. We contrasted a priori and exploratory models that incorporated effects of upland, wetland, weather, female, and brood-related variables on duckling survival rates. Survival was highest for Ducklings when a greater proportion of their surrounding landscape (i.e., within a 500-m radius buffer around the brood) was comprised of wetlands characterized by a central expanse of open water and a peripheral ring of flooded emergent vegetation. Cold and wet weather in the first week of life resulted in lower duckling survival. In a post hoc analysis, duckling survival (of older Ducklings) was negatively related to increasing proportions of managed hayland. © 2011 The Wildlife Society.
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seasonal variation in pre fledging survival of lesser scaup aythya affinis hatch date effects depend on maternal body mass
Journal of Avian Biology, 2012Co-Authors: Kirsty Gurney, Robert G. Clark, Stuart M SlatteryAbstract:Among temperate-breeding birds, offspring survival and reproductive success are often inversely related to timing of breeding. The mechanisms that produce seasonal declines in offspring survival are not fully understood but may be related to temporal changes in parental quality, environmental quality, or both. We analyzed data for lesser scaup Aythya affinis to evaluate hypothesized effects of parental quality and date on pre-fledging survival. Maternal quality, as indexed by body mass, did not have an independent effect on offspring survival in this species. Maternal body mass did not decline seasonally and did not have an independent effect on duckling survival. Although we did not detect an independent effect of hatch date on duckling survival, duckling survival declined seasonally for broods raised by lightweight females, indicating an interactive effect of maternal mass and date. We hypothesize that this interaction may be driven by seasonally declining food resources coupled with the influence of female condition on the ability to monopolize food resources or remain attentive to the brood. We also tested morphological predictions of the date hypothesis by examining physical characteristics of Ducklings. When corrected for age and size, late-hatched Ducklings tended to have marginally larger digestive systems and smaller leg muscles than did early-hatched birds. Abundances of intestinal parasites acquired through diet decreased marginally in late-hatched Ducklings. Results for digestive system and parasite infection patterns suggested that later-hatched broods may shift diets, consistent with a contribution of environmental factors to seasonal variation in offspring survival. Taken together, our results suggest that both female attributes and environmental conditions may influence seasonal patterns of offspring survival in this species.
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consequences of egg size for offspring survival a cross fostering experiment in ruddy ducks oxyura jamaicensis
The Auk, 2003Co-Authors: Jeffrey T Pelayo, Robert G. ClarkAbstract:Abstract In birds, large egg size often enhances subsequent offspring survival, but most previous studies have been unable to separate effects of egg size from other maternal influences. Therefore, we first evaluated variance components of egg size both within and among individual female Ruddy Ducks (Oxyura jamaicensis), and then tested for egg-size-dependent survival of Ducklings in the wild by switching complete broods among females. Forty broods consisting of 244 individually color-marked, day-old Ducklings of known egg size were given to foster mothers, and survival was monitored to one month. Analysis of mark–resighting data showed that offspring survival was best modeled to include effects of egg size and hatching date; survival probability increased with egg size, but declined with advancing hatching date. Duckling body mass, body size, and body condition measured at hatching were positively correlated with egg size. Unlike most other duck species, and for reasons that are speculative, egg sizes va...
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factors affecting survival of northern pintail Ducklings in alberta
The Condor, 1999Co-Authors: Karla L Guyn, Robert G. ClarkAbstract:We determined brood and duckling survival from 57 radio-marked Northern Pintail (Anas acuta) females in southern Alberta during 1994-1996, and related duckling survival to maternal and environmental attributes. Annual brood survival estimates ranged from 72.2% to 88.2%. Brood survival declined with hatch date in all years. Duckling survival was highest in 1994 at 65.2%, but fell to 42.4% and 43.8% in 1995 and 1996, respectively. Duckling mortality was highest during the first 10 days post-hatch in all years. Duckling survival did not vary with female age, or distance from nest to nearest wetland, but did decline throughout the breeding season. Duckling survival was higher for Ducklings from larger broods in 1994, but the opposite trend was found in 1995 and 1996.
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effects of variation in egg size and hatching date on survival of lesser scaup aythya affinis Ducklings
Ibis, 1996Co-Authors: Russell D. Dawson, Robert G. ClarkAbstract:The consequences of avian egg-size variation on offspring quality and survival remain unclear. We evaluated the effects of egg-size and hatch-date variation on survival of Lesser Scaup Aythya affinis Ducklings in the wild. Duckling mass at hatching increased significantly with increasing egg size. Ducklings from larger eggs survived better than those from smaller eggs. We suspect that Ducklings from larger eggs survived better because of advantages associated with larger or more efficient utilization of nutrient reserves, or both. We were unable to detect any within-clutch differences in egg size of survivors and non-survivors, nor any consistent direction in the difference in egg size between survivors and nonsurvivors within clutches. This suggests that within-clutch variation may be insufficient to have survival consequences for offspring. In addition, Ducklings that hatched later in the breeding season had a higher probability of survival. We suggest a food-dependent hypothesis as an explanation for the seasonally increasing survival and for later nest initiation of Lesser Scaup compared with other North American ducks.
Guangqing Liu - One of the best experts on this subject based on the ideXlab platform.
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Immunization with a suicidal DNA vaccine expressing the E glycoprotein protects Ducklings against duck Tembusu virus
BMC, 2018Co-Authors: Jingyu Tang, Mingyang Ding, Dongdong Yin, Jie Zhu, Li Zhang, Qiuhong Miao, Yingqi Zhu, Guijun Wang, Guangqing LiuAbstract:Abstract Backgroud Duck Tembusu virus (DTMUV), a pathogenic flavivirus, emerged in China since 2010 and causing huge economic loss in the Chinese poultry industry. Although several vaccines have been reported to control DTMUV disease, few effective vaccines are available and new outbreaks were continuously reported. Thus, it is urgently to develop a new effective vaccine for prevention of this disease. Methods In this study, a suicidal DNA vaccine based on a Semliki Forest virus (SFV) replicon and DTMUV E glycoprotein gene was constructed and the efficacy of this new vaccine was assessed according to humoral and cell-mediated immune responses as well as protection against the DTMUV challenge in Ducklings. Results Our results showed that the recombinant SFV replicon highly expressed E glycoprotein in DEF cells. After intramuscular injection of this new DNA vaccine in Ducklings, robust humoral and cellular immune responses were observed in all immunized Ducklings. Moreover, all Ducklings were protected against challenge with the virulent DTMUV AH-F10 strain. Conclusions In conclusion, we demonstrate that this suicidal DNA vaccine is a promising candidate facilitating the prevention of DTMUV infection
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protective immune responses in Ducklings induced by a suicidal dna vaccine of the vp1 gene of duck hepatitis virus type 1
Veterinary Microbiology, 2012Co-Authors: Zongyan Chen, Guangqing LiuAbstract:A suicidal DNA vaccine based on a Semliki Forest virus (SFV) replicon was evaluated for the development of a vaccine against duck hepatitis virus type 1 (DHV-1). The VP1 gene of DHV-1 was cloned and inserted into pSCA1, an SFV DNA-based replicon vector. The resultant plasmid, pSCA/VP1, was transfected into BHK-21 cells and the antigenicity of the expressed protein was confirmed using an indirect immunofluorescence and western blot assay. Immunogenicity was studied in Ducklings. Ducklings were injected intramuscularly two times with pSCA/VP1 at 14 days intervals. Anti-DHV-1 antibodies were detected by ELISA, the lymphocyte proliferation response was also tested by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide method and neutralizing antibodies were measured by microneutralization tests. Our results showed that DHV-1-specific antibodies, neutralizing antibodies and lymphocyte proliferation were well induced in Ducklings. Furthermore, all the Ducklings were protected against challenge with wild DHV-1. In conclusion, we demonstrate that the suicidal DNA vaccine is a promising vaccine candidate facilitating the prevention of duck hepatitis caused by DHV-1.
Xuelian Zhang - One of the best experts on this subject based on the ideXlab platform.
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Comparative liver transcriptome analysis in Ducklings infected with duck hepatitis A virus 3 (DHAV-3) at 12 and 48 hours post-infection through RNA-seq
Veterinary Research, 2018Co-Authors: Xuelian Zhang, Chong Cao, Yue Liu, Wenjing Zhang, Chunxue Hao, Haotian Chen, Qi Zhang, Wenlong Zhang, Mingchun Gao, Junwei WangAbstract:AbstractDuck hepatitis A virus 3 (DHAV-3), the only member of the novel genus Avihepatovirus, in the family Picornaviridae, can cause significant economic losses for duck farms in China. Reports on the pathogenicity and the antiviral molecular mechanisms of the lethal DHAV-3 strain in Ducklings are inadequate and remain poorly understood. We conducted global gene expression profiling and screened differentially expressed genes (DEG) of duckling liver tissues infected with lethal DHAV-3. There were 1643 DEG and 8979 DEG when compared with mock Ducklings at 12 hours post-infection (hpi) and at 48 hpi, respectively. Gene pathway analysis of DEG highlighted mainly biological processes involved in metabolic pathways, host immune responses, and viral invasion. The results may provide valuable information for us to explore the pathogenicity of the virulent DHAV-3 strain and to improve our understanding of host–virus interactions.
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MOESM3 of Comparative liver transcriptome analysis in Ducklings infected with duck hepatitis A virus 3 (DHAV-3) at 12 and 48Â hours post-infection through RNA-seq
2018Co-Authors: Xuelian Zhang, Chong Cao, Yue Liu, Wenjing Zhang, Chunxue Hao, Haotian Chen, Qi Zhang, Wenlong Zhang, Mingchun GaoAbstract:Additional file 3. Differentially expressed genes in the uninfected and 12Â hpi duckling livers. The list of all differentially expressed genes in the livers of Ducklings in the control group and 12Â hpi group
Todd J. Applegate - One of the best experts on this subject based on the ideXlab platform.
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growth serum biochemistry complement activity and liver gene expression responses of pekin Ducklings to graded levels of cultured aflatoxin b1
Poultry Science, 2014Co-Authors: X. Chen, N Horn, P F Cotter, Todd J. ApplegateAbstract:Abstract A 14-d study was conducted to evaluate the effects of cultured aflatoxin B1 (AFB1) on performance, serum biochemistry, serum natural antibody and complement activity, and hepatic gene expression parameters in Pekin Ducklings. A total of 144 male Pekin Ducklings were weighed, tagged, and randomly allotted to 4 dietary treatments containing 4 concentrations of AFB1 (0, 0.11, 0.14, and 0.21 mg/kg) from 0 to 14 d of age (6 cages per diet; 6 Ducklings per cage). Compared with the control group, there was a 10.9, 31.7, and 47.4% (P
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growth serum biochemistry complement activity and liver gene expression responses of pekin Ducklings to graded levels of cultured aflatoxin b1
Poultry Science, 2014Co-Authors: X. Chen, N Horn, P F Cotter, Todd J. ApplegateAbstract:A 14-d study was conducted to evaluate the effects of cultured aflatoxin B1 (AFB1) on performance, serum biochemistry, serum natural antibody and complement activity, and hepatic gene expression parameters in Pekin Ducklings. A total of 144 male Pekin Ducklings were weighed, tagged, and randomly allotted to 4 dietary treatments containing 4 concentrations of AFB1 (0, 0.11, 0.14, and 0.21 mg/kg) from 0 to 14 d of age (6 cages per diet; 6 Ducklings per cage). Compared with the control group, there was a 10.9, 31.7, and 47.4% (P < 0.05) decrease in cumulative BW gain with 0.11, 0.14, and 0.21 mg of AFB1/kg of diet, respectively, but feed efficiency was not affected. Increasing concentrations of AFB1 reduced cumulative BW gain and feed intake both linearly and quadratically, and regression equations were developed with r(2) ≥0.73. Feeding 0.11 to 0.21 mg of AFB1/kg reduced serum glucose, creatinine, albumin, total protein, globulin, Ca, P, and creatine phosphokinase linearly, whereas serum urea N, Cl, alkaline phosphatase, and aspartate amino transferase concentrations increased linearly with increasing AFB1 (P < 0.05). Additionally, 0.11 to 0.21 mg of AFB1/kg diets impaired classical and alternative complement pathways in the duckling serum when tested by lysis of rabbit, human type O, and horse erythrocytes, and decreased rabbit and horse agglutinins (P < 0.05). Liver peroxisome proliferator activated receptor α (PPARα) expression was linearly downregulated by AFB1 (P < 0.01). Results from this study indicate that for every 0.10 mg/kg increase in dietary AFB1, cumulative feed intake and BW gain decrease approximately 230 and 169 g per duckling from hatch to 14 d; and that AFB1 at very low concentrations can significantly impair liver function and gene expression, and innate immune dynamics in Pekin Ducklings.
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Comparative development of the small intestine in the turkey poult and Pekin duckling
Poultry science, 2005Co-Authors: Todd J. Applegate, Darrin M. Karcher, M. S. LilburnAbstract:Turkey poults and Pekin Ducklings hatch from eggs of similar weights and have the same incubation periods and body weights at hatch. The male Pekin duckling, however, can attain a market weight of 3.2 kg in approximately 6 wk, whereas at the same age, male turkeys only weigh approximately 2.1 kg. For this study, fertile turkey eggs (n = 400, mean weight: 87.2 g, range: 85 to 89.9 g) and Pekin duck eggs (n = 565, mean weight: 88.6 g, range: 85 to 92.0 g) were weighed and incubated. Embryos and hatchlings were sampled during the last week of incubation, at hatch, and through 7 d of age. Yolk-free BW of poults were 2.7 g heavier than Ducklings at hatch. Yolk-free BW of Ducklings, however, were greater than poults at 1 d of age (P > or = 0.06), and by 7 d of age Ducklings were 140 g heavier (P < or = 0.01). Yolk sac weight was similar at 21 and 25 d of incubation, yet was significantly lower in ducks at hatch, 1, and 2 d of age (P < or = 0.05). In the duckling, jejunum and ileum weights (3.7x heavier), length (1.6x longer), and density (g/cm; 2.3x more dense) were consistently heavier than in the turkey from hatch through 7 d (P < or = 0.01). Histological sections of the distal jejunum revealed more rapid villus growth in the duck from 0 to 3 d of age. The combination of increased intestinal growth (weight and length) and maturation (villus length) allowed ducks to achieve an additional 143 g of BW gain during the critical hatch through 7 d of growth.
