AIM: To analyze the difference of intestinal microbial community diversity between healthy and (S. enteritidis) orally infected ducklings.METHODS: Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR was applied...AIM: To analyze the difference of intestinal microbial community diversity between healthy and (S. enteritidis) orally infected ducklings.METHODS: Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR was applied to analyze the intestinal microbial community diversity and dynamic change including duodenum, jejunum, ileum, cecum and rectum from healthy ducklings and 7-day-old ducklings after oral infection with S. enteritidis at different time points.RESULTS: The intestinal microbial community of the control healthy ducklings was steady and the ERIC-PCR band numbers of the control healthy ducklings were the least with rectum and were the most with caecum. ERIC-PCR bands of orally inoculated ducklings did not obviously change until 24 h after inoculation (p.i.). The numbers of the ERIC-PCR bands gradually decreased from 24 h to 72 h p.i., and then, with the development of disease, the band numbers gradually increased until 6 d p.i. The prominent bacteria changed because of S. enteritidis infection and the DNAstar of staple of ERIC-PCR showed that aerobe and facultative aerobe (Escherichia coli, Shigella, Salmonella) became preponderant bacilli in the intestine of orally infected ducklings with SE.CONCLUSION: This study has provided significant data to clarify the intestinal microbial community diversity and dynamic change of healthy and S. enteritidis orally infected ducklings, and valuable insight into the pathogenesis of S. enteritidis infection in both human and animals.展开更多
A feed trial was conducted with a total of 1 134 Beijing ducklings to study the optimum level of dietary lysine （Lys） （0.95, 1.10, 1.25%）, methionine （Met） （0.26, 0.46, 0.66%） and tryptophan （Trp） （0.20, 0....A feed trial was conducted with a total of 1 134 Beijing ducklings to study the optimum level of dietary lysine （Lys） （0.95, 1.10, 1.25%）, methionine （Met） （0.26, 0.46, 0.66%） and tryptophan （Trp） （0.20, 0.30, 0.40%） for those ducklings during a phase of 0-2 weeks. Ducklings were randomly allotted to 27 groups according to a 3 × 3× 3 factorial arrangement and fed a basal corn-soybean-peanut meal diet containing 20.26% CP, 12.45 MJ kg^-1 ME. The results from this study indicate that Lys affected body weight （P〈0.01）, feed intake （0-14 d） （P〈0.01）, but had no effect on feed/gain （0-14 d） （P〉0.05）, uric acid concentration （P 〉 0.05）. Methionine influenced body weight （P 〈 0.01）, feed/gain （P 〈 0.05）, and feed intake （P 〈 0.01）. Tryphtophan had no effect on indices measured. The requirement of the Lys and Met for Beijing ducklings of 0-2 weeks of age were 1.10 and 0.46%. The requirement of Trp for Beijing ducklings of 0-2 weeks of age was not more than 0.20%.展开更多
one-day-old Tianfu meat ducklings were divided into three groups, and fed on dietsas follows:(1)control (Cu 12.16 mg kg-1),(2) copper toxicⅠ(Cu 850 mg kg-1) and (3)copper toxicⅡ( Cu 1050 mg kg-1) for studies on effe...one-day-old Tianfu meat ducklings were divided into three groups, and fed on dietsas follows:(1)control (Cu 12.16 mg kg-1),(2) copper toxicⅠ(Cu 850 mg kg-1) and (3)copper toxicⅡ( Cu 1050 mg kg-1) for studies on effects of copper toxicity on lymphoidorgans in duckling with the methods of experimental pathology and flow cytometry (FCM).The weight and growth index of the thymus, spleen and bursa of Fabricius were markedlyreduced (P<0.05 or P<0.01) in both copper toxic groupⅠand Cu toxic group Ⅱ whencompared with control group. The G0/G1 phase of the cell cycle of the thymus, spleen andbursa of Fabricius was much higher, and S, G2+M phases lower in Cu toxic groupsⅠand Ⅱthan in the control group. There were lymphocyte degeneration and depletion of lymphoidorgans, and the reticular cells of spleen and bursa of Fabricius proliferated and thereticular cells of thymus were also degenerate and necrotic in Cu toxic groups. Theresults demonstrated that Cu toxicity seriously impaired the progression of lymphocytesfrom the G0/G1 phase to S phase, inhibited the development of lymphoid organs and causedmarked pathological injury in lymphoid organs. The results also showed that the effectof Cu toxicity on the primary lymphoid organs occurred stronger than on the secondarylymphoid organs. The effect of Cu toxicity was the greatest on the bursa of Fabricius,followed by the thymus, and then the spleen. Potential mechanisms underlying aforementionedobservation were also discussed.展开更多
To evaluate the effects of duck hepatitis virus-1 （DHV-1） on the body weight gain in duck and the effects of silymarin on it in vivo, 100 10-d-old ducks, both male and female, were collected to be subjected to the t...To evaluate the effects of duck hepatitis virus-1 （DHV-1） on the body weight gain in duck and the effects of silymarin on it in vivo, 100 10-d-old ducks, both male and female, were collected to be subjected to the test. The experiments were conducted in 8 groups： in group 1-3, the animals were inoculated with 1：105 diluted duck hepatitis virus （DHV-1） infected allantoic fluid and given 0, 30, and 50 mg kg^-1 BW d^-1 silymarin orally, respectively. In group 4-6, the animals were inoculated with 1：5 × 105 diluted DHV-1 infected allantoic fluid and given 0, 10, and 30 mg kg^-1 BW d^-1 silymarin orally, respectively. In group 7, the animals were given 10 mg kg^-1 BW d^-1 silymafin only. Group 8 was the control one treated by injecting sterillized saline into the leg muscles. All the silymarin was given from 0 to 4 d after inoculation of the virus. By the 5th d after inoculation, the vein blood was drawn from the dorsal foot vein and the plasma samples were collected and stored at -20℃. The body weight gain （BWG） was measured from 0 to 10 d after inoculation. The plasma IGF-I, T3, and T4 concentrations were measured by radioimmunoassay （RIA）. At the virus dose of 1：5 ×105 diluted virus infected allantoic fluid, the inoculation of the virus enhanced the BWG significantly compared with that of the control （P〈 0.01）, while 10-50 mg kg^-1 BW d^-1 silymarin could counteract the effects of the virus on the BWG dose-dependently. The plasma IGF-I levels showed no correlation with the BWG, but the T3 levels showed a same tropism with the body weight gain. The present results indicated that sublethal DHV-1 enhanced the body weight gain of ducklings significantly, and the silymarin could counteract this effect in vivo.展开更多
One-day-old healthy ducklings （n = 100） were randomly allocated into two groups （n = 50, respectively） to investigate the effect of cytokines on ducklings with selenium poisoning. The ducklings in control group （...One-day-old healthy ducklings （n = 100） were randomly allocated into two groups （n = 50, respectively） to investigate the effect of cytokines on ducklings with selenium poisoning. The ducklings in control group （Group Ⅰ） were fed with full rations containing 0.3 mg kg^-1 selenium, and the ducklings in selenium poisoning group （Group Ⅱ ） were fed with seleniumexcessive rations containing 8.0 mg kg^-1 selenium. One mL blood was collected by cardiac puncture at d 15, 30, 60, and 90 （n = 10, respectively）, serum was separated by centrifugation. Contents of cytokines were determined by the radioimmunity method （RIA）. The results showed that the contents of IL-113, IL-213 in Group Ⅱ were higher than that in control group at d 15 （P〉0.05）, but were significantly lower at d 30, 60, and 90 （P〈0.01）; the contents of IL-8β in Group II were significantly lower than that in control group （P〈0.01）; the contents of erythropoietin （EPO） and IGF-2 in Group II were significantly lower in different degree than that in control group at d 60 and 90 （P〈0.01）; the contents of granulocyte- macrophage colony stimulating factor （GM-CSF） in the two groups were lower in different degree and significantly lower at d 60 and 90 （P〈0.01）. It can be concluded that the excessive selenium could result in a decrease in immunity and a series of clinical pathology changes, such as anemia, tissue hemorrhage, and necrosis.展开更多
One-day-old healthy ducklings(n=100)were divided into control group and experimental group randomly, and selenium poisoning of ducklings was artificially caused by feeding ration containing 8 mg kg-1 Se every day. The...One-day-old healthy ducklings(n=100)were divided into control group and experimental group randomly, and selenium poisoning of ducklings was artificially caused by feeding ration containing 8 mg kg-1 Se every day. The dynamic changes of No content and NOS activity in the serum and tissues were determined by means of the method of nitric acid reductase. Results showed that the NO content and NOS activity in serum and tissues in experimental group increased significantly(P<0. 05)and they were time-dependent. It was suggested that the high level of selenium in bodies could increase the NOS activity and NO content as it destroyed the metabolism of material and energy as well as structure and function of tissues and cells. These changes of NO content and NOS activity might be involved in the metabolism of selenium poisoning.展开更多
20 one-day-old Tianfu ducklings were fed on a natural diet deficient in phosphorus (Ca 0.80%, P 0.366%) for three weeks and examined for signs and lesions. Signs began to appear at the age of one week, and became seri...20 one-day-old Tianfu ducklings were fed on a natural diet deficient in phosphorus (Ca 0.80%, P 0.366%) for three weeks and examined for signs and lesions. Signs began to appear at the age of one week, and became serious at two weeks. 13 ducklings died during the experiment. Morbidity was 100% and mortality was 65%. The affected ducklings mainly showed leg weakness, severe lameness, depression, lack of appetite and stunted growth. The serum alkaline phosphatasc activities increased markedly. The scrum phosphorus concentration, tibial ash, ash calcium and phosphorus content decreased obviously. At necropsy, maxillae and ribs were soft, and the latter was crooked. Long bones were soft and broke easily. The hypcrtrophic zone of the growth- plate in the epiphysis of long bones was lengthened and ostcoid tissue increased in the mctaphyseal spongiosa histopathologically. The above mentioned symptoms and lesions could be prevented by adding phosphorus to the natural deficient diet (up to 0.65%). The relationship between lesions and signs, pathomorphological characterisation and pathogcnsis were also discussed in this paper.展开更多
教学流程:一、课前准备及热身入境1.出示Class rules.确定评价机制。2.Listen and guess.引出故事人物。设计意图:通过听听猜猜的活动,引出本课谈论话题:duckling二、围绕主题,了解故事1.观察封面,了解故事背景知识。T:Look at the cove...教学流程:一、课前准备及热身入境1.出示Class rules.确定评价机制。2.Listen and guess.引出故事人物。设计意图:通过听听猜猜的活动,引出本课谈论话题:duckling二、围绕主题,了解故事1.观察封面,了解故事背景知识。T:Look at the cover of the storybook.What can you see in the picture?Ss:I can see some ducklings.Two are yellow.One展开更多
基金The National Science &Technology Pillar Program, 2007Z06-017Program for New Century Excellent Talents in University, NCET-04-0906/NCET-06-0818+1 种基金Sichuan Province Basic Research Program, 04JY029-006-1/04JY021-100/07JY029-017Program for Key Disciplines Construction of Sichuan Province, SZD0418
文摘AIM: To analyze the difference of intestinal microbial community diversity between healthy and (S. enteritidis) orally infected ducklings.METHODS: Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR was applied to analyze the intestinal microbial community diversity and dynamic change including duodenum, jejunum, ileum, cecum and rectum from healthy ducklings and 7-day-old ducklings after oral infection with S. enteritidis at different time points.RESULTS: The intestinal microbial community of the control healthy ducklings was steady and the ERIC-PCR band numbers of the control healthy ducklings were the least with rectum and were the most with caecum. ERIC-PCR bands of orally inoculated ducklings did not obviously change until 24 h after inoculation (p.i.). The numbers of the ERIC-PCR bands gradually decreased from 24 h to 72 h p.i., and then, with the development of disease, the band numbers gradually increased until 6 d p.i. The prominent bacteria changed because of S. enteritidis infection and the DNAstar of staple of ERIC-PCR showed that aerobe and facultative aerobe (Escherichia coli, Shigella, Salmonella) became preponderant bacilli in the intestine of orally infected ducklings with SE.CONCLUSION: This study has provided significant data to clarify the intestinal microbial community diversity and dynamic change of healthy and S. enteritidis orally infected ducklings, and valuable insight into the pathogenesis of S. enteritidis infection in both human and animals.
文摘A feed trial was conducted with a total of 1 134 Beijing ducklings to study the optimum level of dietary lysine （Lys） （0.95, 1.10, 1.25%）, methionine （Met） （0.26, 0.46, 0.66%） and tryptophan （Trp） （0.20, 0.30, 0.40%） for those ducklings during a phase of 0-2 weeks. Ducklings were randomly allotted to 27 groups according to a 3 × 3× 3 factorial arrangement and fed a basal corn-soybean-peanut meal diet containing 20.26% CP, 12.45 MJ kg^-1 ME. The results from this study indicate that Lys affected body weight （P〈0.01）, feed intake （0-14 d） （P〈0.01）, but had no effect on feed/gain （0-14 d） （P〉0.05）, uric acid concentration （P 〉 0.05）. Methionine influenced body weight （P 〈 0.01）, feed/gain （P 〈 0.05）, and feed intake （P 〈 0.01）. Tryphtophan had no effect on indices measured. The requirement of the Lys and Met for Beijing ducklings of 0-2 weeks of age were 1.10 and 0.46%. The requirement of Trp for Beijing ducklings of 0-2 weeks of age was not more than 0.20%.
文摘one-day-old Tianfu meat ducklings were divided into three groups, and fed on dietsas follows:(1)control (Cu 12.16 mg kg-1),(2) copper toxicⅠ(Cu 850 mg kg-1) and (3)copper toxicⅡ( Cu 1050 mg kg-1) for studies on effects of copper toxicity on lymphoidorgans in duckling with the methods of experimental pathology and flow cytometry (FCM).The weight and growth index of the thymus, spleen and bursa of Fabricius were markedlyreduced (P<0.05 or P<0.01) in both copper toxic groupⅠand Cu toxic group Ⅱ whencompared with control group. The G0/G1 phase of the cell cycle of the thymus, spleen andbursa of Fabricius was much higher, and S, G2+M phases lower in Cu toxic groupsⅠand Ⅱthan in the control group. There were lymphocyte degeneration and depletion of lymphoidorgans, and the reticular cells of spleen and bursa of Fabricius proliferated and thereticular cells of thymus were also degenerate and necrotic in Cu toxic groups. Theresults demonstrated that Cu toxicity seriously impaired the progression of lymphocytesfrom the G0/G1 phase to S phase, inhibited the development of lymphoid organs and causedmarked pathological injury in lymphoid organs. The results also showed that the effectof Cu toxicity on the primary lymphoid organs occurred stronger than on the secondarylymphoid organs. The effect of Cu toxicity was the greatest on the bursa of Fabricius,followed by the thymus, and then the spleen. Potential mechanisms underlying aforementionedobservation were also discussed.
基金supported by the National Natural Science Foundation of China (30571341)Foshan Science and Technology Development Programme,China(04040111)
文摘To evaluate the effects of duck hepatitis virus-1 （DHV-1） on the body weight gain in duck and the effects of silymarin on it in vivo, 100 10-d-old ducks, both male and female, were collected to be subjected to the test. The experiments were conducted in 8 groups： in group 1-3, the animals were inoculated with 1：105 diluted duck hepatitis virus （DHV-1） infected allantoic fluid and given 0, 30, and 50 mg kg^-1 BW d^-1 silymarin orally, respectively. In group 4-6, the animals were inoculated with 1：5 × 105 diluted DHV-1 infected allantoic fluid and given 0, 10, and 30 mg kg^-1 BW d^-1 silymarin orally, respectively. In group 7, the animals were given 10 mg kg^-1 BW d^-1 silymafin only. Group 8 was the control one treated by injecting sterillized saline into the leg muscles. All the silymarin was given from 0 to 4 d after inoculation of the virus. By the 5th d after inoculation, the vein blood was drawn from the dorsal foot vein and the plasma samples were collected and stored at -20℃. The body weight gain （BWG） was measured from 0 to 10 d after inoculation. The plasma IGF-I, T3, and T4 concentrations were measured by radioimmunoassay （RIA）. At the virus dose of 1：5 ×105 diluted virus infected allantoic fluid, the inoculation of the virus enhanced the BWG significantly compared with that of the control （P〈 0.01）, while 10-50 mg kg^-1 BW d^-1 silymarin could counteract the effects of the virus on the BWG dose-dependently. The plasma IGF-I levels showed no correlation with the BWG, but the T3 levels showed a same tropism with the body weight gain. The present results indicated that sublethal DHV-1 enhanced the body weight gain of ducklings significantly, and the silymarin could counteract this effect in vivo.
文摘One-day-old healthy ducklings （n = 100） were randomly allocated into two groups （n = 50, respectively） to investigate the effect of cytokines on ducklings with selenium poisoning. The ducklings in control group （Group Ⅰ） were fed with full rations containing 0.3 mg kg^-1 selenium, and the ducklings in selenium poisoning group （Group Ⅱ ） were fed with seleniumexcessive rations containing 8.0 mg kg^-1 selenium. One mL blood was collected by cardiac puncture at d 15, 30, 60, and 90 （n = 10, respectively）, serum was separated by centrifugation. Contents of cytokines were determined by the radioimmunity method （RIA）. The results showed that the contents of IL-113, IL-213 in Group Ⅱ were higher than that in control group at d 15 （P〉0.05）, but were significantly lower at d 30, 60, and 90 （P〈0.01）; the contents of IL-8β in Group II were significantly lower than that in control group （P〈0.01）; the contents of erythropoietin （EPO） and IGF-2 in Group II were significantly lower in different degree than that in control group at d 60 and 90 （P〈0.01）; the contents of granulocyte- macrophage colony stimulating factor （GM-CSF） in the two groups were lower in different degree and significantly lower at d 60 and 90 （P〈0.01）. It can be concluded that the excessive selenium could result in a decrease in immunity and a series of clinical pathology changes, such as anemia, tissue hemorrhage, and necrosis.
文摘One-day-old healthy ducklings(n=100)were divided into control group and experimental group randomly, and selenium poisoning of ducklings was artificially caused by feeding ration containing 8 mg kg-1 Se every day. The dynamic changes of No content and NOS activity in the serum and tissues were determined by means of the method of nitric acid reductase. Results showed that the NO content and NOS activity in serum and tissues in experimental group increased significantly(P<0. 05)and they were time-dependent. It was suggested that the high level of selenium in bodies could increase the NOS activity and NO content as it destroyed the metabolism of material and energy as well as structure and function of tissues and cells. These changes of NO content and NOS activity might be involved in the metabolism of selenium poisoning.
文摘20 one-day-old Tianfu ducklings were fed on a natural diet deficient in phosphorus (Ca 0.80%, P 0.366%) for three weeks and examined for signs and lesions. Signs began to appear at the age of one week, and became serious at two weeks. 13 ducklings died during the experiment. Morbidity was 100% and mortality was 65%. The affected ducklings mainly showed leg weakness, severe lameness, depression, lack of appetite and stunted growth. The serum alkaline phosphatasc activities increased markedly. The scrum phosphorus concentration, tibial ash, ash calcium and phosphorus content decreased obviously. At necropsy, maxillae and ribs were soft, and the latter was crooked. Long bones were soft and broke easily. The hypcrtrophic zone of the growth- plate in the epiphysis of long bones was lengthened and ostcoid tissue increased in the mctaphyseal spongiosa histopathologically. The above mentioned symptoms and lesions could be prevented by adding phosphorus to the natural deficient diet (up to 0.65%). The relationship between lesions and signs, pathomorphological characterisation and pathogcnsis were also discussed in this paper.
文摘教学流程:一、课前准备及热身入境1.出示Class rules.确定评价机制。2.Listen and guess.引出故事人物。设计意图:通过听听猜猜的活动,引出本课谈论话题:duckling二、围绕主题,了解故事1.观察封面,了解故事背景知识。T:Look at the cover of the storybook.What can you see in the picture?Ss:I can see some ducklings.Two are yellow.One
