This article examines Chinese roast duck,with particular emphasis on Cantonese roast duck.It traces the origin of roast duck to the Northern and Southern Dynasties and describes its development through various dynasti...This article examines Chinese roast duck,with particular emphasis on Cantonese roast duck.It traces the origin of roast duck to the Northern and Southern Dynasties and describes its development through various dynasties.Roast duck played an important role in military,court,and folk life,and left evidence in many ancient books.The article introduces the preparation methods of Beijing,Nanjing,and Cantonese roast ducks.It analyzes the significance of Cantonese roast duck in Cantonese culinary culture and distinguishes roast duck from roast goose.It argues that Chinese roast duck,particularly Cantonese roast duck,is a distinguished and historically significant element of Chinese culinary culture,whose development reflects the evolution of regional cooking techniques,social customs,and cultural values from ancient times to the present.By tracing the origins,historical development,and cultural significance of roast duck,the article highlights its role as both a culinary symbol and a vehicle for understanding broader patterns of Chinese food culture,thereby contributing to the appreciation and global recognition of Chinese cuisine.展开更多
Background AflatoxinB1(AFB_(1))is a prevalent contaminant in agricultural products,presenting significant risks to animal health.CotA laccase from Bacillus licheniformis has shown significant efficacy in degrading myc...Background AflatoxinB1(AFB_(1))is a prevalent contaminant in agricultural products,presenting significant risks to animal health.CotA laccase from Bacillus licheniformis has shown significant efficacy in degrading mycotoxins in vitro test.The efficacy of Bacillus CotA laccase in animals,however,remains to be confirmed.A 2×2 factorial design was used to investigate the effects of Bacillus CotA laccase level(0 or 1 U/kg),AFB_(1) challenge(challenged or unchal-lenged)and their interactions on ducks.The purpose of this study was to evaluate the efficacy of Bacillus CotA laccase in alleviatingAFB_(1) toxicosis of ducks.Results Bacillus CotA laccase alleviatedAFB_(1)-induced declines in growth performance of ducks accompanied by improved average daily gain(ADG)and lower feed/gain ratio(F/G).Bacillus CotA laccase amelioratedAFB_(1)-induced gut barrier dysfunctions and inflammation testified by increasing the jejunal villi height/crypt depth ratio(VH/CD)and the mRNA expression of tight junction protein 1(TJP1)and zonula occluden-1(ZO-1)as well as decreasing the expression of inflammation-related genes in the jejunum of ducks.Amino acid metabolome showed that Bacillus CotA laccase amelioratedAFB_(1)-induced amino acid metabolism disorders evidenced by increasing the level of glu-tamic acid in serum and upregulating the expression of amino acid transport related genes in jejunum of ducks.Bacil-lus CotA laccase amelioratedAFB_(1)-induced liver injury testified by suppressing oxidative stress,inhibiting apoptosis,and downregulating the expression of hepatic metabolic enzyme related genes of ducks.Moreover,Bacillus CotA laccase degradedAFB_(1) in digestive tract of ducks,resulting in the reduced absorption level ofAFB_(1) across intestinal epithelium testified by the decreased level ofAFB_(1)-DNA adduct in the liver,and the reduced content ofAFB_(1) residues in liver and feces of ducks.Conclusions Bacillus CotA laccase effectively improved the growth performance,intestinal health,amino acid metabolism and hepatic aflatoxin metabolism of ducks fedAFB_(1) diets,highlighting its potential as an efficient and safe feed enzyme forAFB_(1) degradation in animal production.展开更多
TypeⅠinterferon(IFN)-mediated innate immune responses represent the first line of host defense against viral infection.However,the molecular mechanisms by which avian infuenza virus(AIV)inhibits typeⅠIFN production ...TypeⅠinterferon(IFN)-mediated innate immune responses represent the first line of host defense against viral infection.However,the molecular mechanisms by which avian infuenza virus(AIV)inhibits typeⅠIFN production in ducks are not well understood.Here,we frst found that the polymerase basic 2(PB2)protein of H5N1 subtype AIV inhibited the typeⅠIFN responses by targeting duck mitochondrial antiviral signaling protein(MAVS).We further demonstrated that H5N1-PB2 bound to theΔtransmembrane(ΔTM)domain of duck MAVS,and the polymerase basic 1(PB1)binding domain(PBD)and RNA binding nuclear import domain(RND)of H5N1-PB2 interacted with MAVS to inhibit typeⅠIFN expression in ducks.Collectively,our fndings contribute to understanding the molecular mechanism by which AIV proteins regulate the retinoic acid-inducible geneⅠ(RIG-Ⅰ)-like receptor(RLR)signaling pathway to evade host antiviral immune responses in ducks.展开更多
Duck species are important vectors for seed dispersal of many plants,contributing significantly to the regeneration of wetland plant communities.However,research on the temporal changes in diet and the dynamics and di...Duck species are important vectors for seed dispersal of many plants,contributing significantly to the regeneration of wetland plant communities.However,research on the temporal changes in diet and the dynamics and differences of seed dispersal among different duck species is still limited.In this study,we analyzed the diversity of duck community and the diversity of seeds in the feces of different duck species from December to February for 2022–23 and 2023–24 in the coastal wetland of Dafeng,eastern Jiangsu Province,China.A total of 13 duck species were recorded in the four habitats,of which Spot-billed Ducks(Anas zonorhyncha)and Mallards(A.platyrhynchos)were the most abundant.The diversity and abundance of ducks vary across different habitats,and tidal flat supports the greatest diversity and abundance of ducks.We collected fecal samples from Spot-billed Ducks,Gadwalls(Mareca strepera),Mallards,and Eurasian Teals(A.crecca)in the tidal flat,from which seeds belonging to 7 families,13 genera and 15 different plant species were obtained.There were significant differences in seed dispersal among the four duck species,which varied with the season.Gadwalls and Common Teals showed more significant diversity in seed dispersal,with their feces containing a greater variety of plant seeds,which is related to their broader dietary range and ecological adaptability.Furthermore,the seasonal variation in the number of seeds per feces reflected the availability of seeds in the habitat and the response of ducks to environmental changes,while variations in seed intake among different duck species may be associated with inter-annual weather condition changes.The results of this study will provide a new perspective for understanding the mechanisms of bird-mediated seed dispersal in coastal wetland and offer preliminary insights for the seed dispersal by Asian ducks.展开更多
[Objective] The aim of this study was to investigate the development rule of muscle fiber in different duck breeds during various developmental stages. [Method] Cherry valley duck, Jinding duck, White muscory duck and...[Objective] The aim of this study was to investigate the development rule of muscle fiber in different duck breeds during various developmental stages. [Method] Cherry valley duck, Jinding duck, White muscory duck and Suma duck （ Cherry valley duck ♂ × Jinding duck ♀ ） were fed for 10 weeks to observe the ultrastructure of muscle fiber by electron microscope, and the myofibril diameter and sarcomere length were also determined. [Result] The myofibril diameter increased with ages. Sarcomere length and myofibril diameter did not change significantly with the increasing ages （P〉0.05）. The myofibril diameter of White muscory duck and Jinding duck were thicker, while that of Cherry valley cluck and Suma duck were thinner. Moreover, the sarcomere length of Suma duck and White muscory duck were longer, while that of Cherry valley duck and Jinding duck were shorter. Thus, the basic characteristics of ultrastructure of muscle fiber were consistent in these duck breeds.[Conclusion] The results have an important meaning for duck breeding.展开更多
[Objective] The aim was to improve the quality of the duck blood tofu by ultrasonic technology. [Method] Ultrasonic technology was used to break the blood cell membrane. The optimal ultrasonic condition was determined...[Objective] The aim was to improve the quality of the duck blood tofu by ultrasonic technology. [Method] Ultrasonic technology was used to break the blood cell membrane. The optimal ultrasonic condition was determined by single factor de- sign, and the differences in sensory quality and nutritional value between the duck blood tofu treated with and without ultrasonication were studied. [Result] The optimal ultrasonic power was 400 W and the optimal ultrasonic time was 6 min. Under these conditions, the content of duck blood haemoglobin increased by 43.46%, the content of iron increased by 10.85%, and the breakage rate was 100%. The a＊ value of the duck blood tofu increased significantly under ultrasonic treatment. Both internal micro-structure and texture parameters proved that the ultrasonic contributed to the formation of gel structure. After treatment by artificial gastric juice and artifi- cial intestinal juice, the total amino acids in the digestive juice were 9.25% higher than that of the duck blood tofu without ultrasonic treatment. [Conclusion] The duck blood tofu under ultrasonic treatment would be beneficial to human body absorption, and the nutrition value would be higher as well.展开更多
Seventeen microsatellite loci were used to assess the genetic variation and population structure of six endangered duck populations in China. PIC, heterozygosity with two estimators of genetic differentiation （FST an...Seventeen microsatellite loci were used to assess the genetic variation and population structure of six endangered duck populations in China. PIC, heterozygosity with two estimators of genetic differentiation （FST and GST）, and Nei＇s standard genetic distance were evaluated. The results showed that these six endangered duck populations showed high polymorphism. The propor- tion of inter-population subdivision among the six duck populations ranged between 17.0 and 14.7%. The average heterozygosity was 0.706, 0.702, 0.691, 0.676, 0.604, and 0.660 in the Gaoyou, Liancheng, Jinding, Beijing, Shaoxing, and Jianchang ducks, respectively. The average PIC ranged from 0.561 to 0.663. Finally, the results showed higher genetic diversity and difference above the levels of genetic variation among all the populations.展开更多
In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. To...In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. Total 240 1-d-old Cherry Valley ducks were selected, and they were randomly divided into 4 groups, including 1 control group and 3 treatment groups. There were 3 replicates for each group and there were 20 ducks for each replicate. The ducks in the control group were fed the basal diet, and the ducks in the 3 treatment groups were fed the basal diet added with Lactobacillus, Bacillus natto and florfenicol, respectively. The test lasted for 42 d. The results showed that the addition of Lactobacillus and Bacillus natto could improve the average daily weight gain and final average weight （P〈0.05） of Cherry Valley ducks, and reduce the glutamic-pyruvic transaminase ac- tivity, alkaline phosphatase activity and serum urinary nitrogen content in duck blood （P〈0.05） and reduce the creatinine content and total cholesterol content in Cherry Valley ducks （P〉0.05）; at the same time, adding probiotics to feed could also in- crease the grass economic benefits of Cherry Valley ducks. In overall, the effects of adding probiotics were better than those of adding antibiotic.展开更多
A new breeding population of Mandarin Duck （Aix gaIericulata, Linnaeus） was first recorded in 2003 in Jiao- tanzhuang-Hehekou region of Pingshan county, Hebei Province, China. Recently, the gradually increasing popu...A new breeding population of Mandarin Duck （Aix gaIericulata, Linnaeus） was first recorded in 2003 in Jiao- tanzhuang-Hehekou region of Pingshan county, Hebei Province, China. Recently, the gradually increasing population indicates that there are suitable breeding habitats （such as foraging habitats and nesting sites） for Mandarin Duck. However, these habitats are always close to human disturbances, which are the potential risk for their population. Therefore, it is urgent to put forward an applicable protection strategy, in order to strengthen the public awareness for this unprotected population.展开更多
To investigate molecular epidemiology of DuCV in Cherry Valley ducks in China, the complete genomes of six DuCV strains, which were detected from Cherry Valley ducks in China between 2007 and 2008, were sequenced. Seq...To investigate molecular epidemiology of DuCV in Cherry Valley ducks in China, the complete genomes of six DuCV strains, which were detected from Cherry Valley ducks in China between 2007 and 2008, were sequenced. Sequence and phylogenetic analysis were carried out to compare these six strains with another 27 DuCV strains from Mulard duck, Muscovy duck, Pekin ducks and Mule duck. The analysis showed that the six DuCV strains exhibited typical genetic features of the family of DuCV, such as a stem-loop structure, three major open reading frames (Rep, Cap and ORF3), four intergenic repeats and the conserved motifs for rolling circle replication and for the dNTP binding domain located in the Rep protein. Phylogenetic analysis of the nucleotide sequences of the complete genome and Cap gene of these strains together with those that have been previously published demonstrated two distinct DuCV genotypes. The DuCV strains with complete genomes containing 1988 and 1989 nucleotides clustered in genotype A, whereas the strains with complete genomes containing 1991, 1992, 1995 and 1996 nucleotides lay in genotype B. The six DuCV strains from Cherry Valley ducks were divided into the two groups. The results of the study provides some insight into the variation of DuCVs in Cherry Valley ducks.展开更多
To examine the effect of Gankang Suppository on duck hepatitis B virus （DHBV）, the serum biochemistry and hepatic histology in an animal model of DHBV infection, a model of DHBV infection was established by infectin...To examine the effect of Gankang Suppository on duck hepatitis B virus （DHBV）, the serum biochemistry and hepatic histology in an animal model of DHBV infection, a model of DHBV infection was established by infecting 1-day-old Yingtaogu ducklings with DHBV-positive serum. The successful model was confirmed by PCR assay and 48 ducklings infected with DHBV were randomly divided into 3 groups： a Gankang Suppository treatment group, an acyclovir （ACV） group and a DHBV model group （control）, with each group having 16 animals. All the animals were given the medicines for 4 weeks in a row. The serum of the animals was taken 14 and 28 days after the medica- tion and 7 days after drug discontinuation. Real-time PCR was performed to detect the copy numbers of DHBV DNA in the serum. ALT and AST were dynamically monitored. The ducklings were sacrificed on the 7th day after the discontinuation of the treatment and livers were harvested and examined for inflammation and degeneration of liver cells by using HE staining. The results showed that on day 14, 28 after the treatment and day 7 after the withdrawal, the logarithmic values （log） of DHBV DNA copy numbers in ducklings of Gankang Suppository treatment group were significantly lower than that before the treatment （P=0.0092, P=0.0070, P=0.0080, respectively）. Compared with DHBV model control group, the ALT level was significantly decreased （P=0.0020, P=0.0019, respectively） on day 28 after the treatment and on day 7 after the withdrawal. The AST level was also reduced on day 14 after the treatment （P=0.0298）. Compared with the ACV control group, the level of ALT was lower on day 7 after the withdrawal （P=0.0016）. Histologically, the hepatocyte swelling, vacuolous degeneration and acidophilic degeneration in Gankang Suppository treatment group were alleviated 7 days after the withdrawal as compared with model control group （P=0.0282, P=0.0084, P=0.0195, respectively）. It is concluded that Gankang Suppository can effectively suppress DHBV replication, reduce the levels of serum ALT and AST and improve hepatic histology.展开更多
Twelve fluorescence-labeled microsatellite markers were used to analyze the genetic diversity of 12 domestic duck breeds and 2 wild duck breeds to determine the relationship and origin of Chinese domestic duck breeds....Twelve fluorescence-labeled microsatellite markers were used to analyze the genetic diversity of 12 domestic duck breeds and 2 wild duck breeds to determine the relationship and origin of Chinese domestic duck breeds. Gene frequency, effective number of alleles （Ne）, expected heterozygosity （He）, polymorphism information contents （PIC）, inbreeding coefficient in population （Fis）, standard genetic distance （Ds）, and genetic distance （DA） were calculated by FSTAT and distance and phylogenetic analysis after the dates which were output from the Microsatellite-Toolkit software. Genetic distances between 12 domestic duck breeds and 2 wild duck breeds were analyzed by variance analysis. Unweighted pair group method with arithmetic mean （UPGMA） and phylogenetic trees used for cluster analysis were structured. The results indicated that 11 loci had medium- or high-level genetic diversity among the 12 loci, which could be efficiently used in the detection of the genetic parameters of each population. The values of He were 0.5414 to 0.7343, those of PIC proved similar, and those of Fis were 0.1101 to 0.3381 among all populations. All breeds were clustered into three groups by UPGMA phylogenetic trees. Banzui duck was clustered into a separate group. Differences of the DA were analysed by t-test. The results showed that difference in DA between the 12 domestic duck breeds and Lvtou duck and the Banzui duck were very significant （P〈0.01）, indicating that these 12 domestic duck breeds originated from Lvtou wild duck, but not Banzui duck.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
[Objective]The research aimed to study the polymorphism of intron 1 and its effects on prolactin（PRL） gene and body size traits of Jingjiang Partridge Duck.[Method]Taking 96 Jingjiang partridge ducks as materials,th...[Objective]The research aimed to study the polymorphism of intron 1 and its effects on prolactin（PRL） gene and body size traits of Jingjiang Partridge Duck.[Method]Taking 96 Jingjiang partridge ducks as materials,the polymorphism of intron 1 of PRL gene was detected by PCR-RFLP method.And the relationship between the gene polymorphism and body size traits was analyzed.[Result]Intron 1 in PRL gene of Jingjiang Partridge Duck had sequence polymorphism.Two kinds of genotypes（AB and BB） were detected by DraⅠrestriction and genotype BB was dominant in population（91.67%）.The results of Chi-square test indicated that this site was in Hardy-Weinberg equilibrium in Jingjiang Duck（P 〉0.05）.The results of least square analysis showed that the ducks with AB genotype had larger pelvis breadth（P 〈0.01） but smaller chest measurement（P 〈0.05） than those of BB ducks.[Conclusion]It was preliminarily concluded that PRL gene could be regarded as useful candidate gene（marker） for part of body size traits of Jingjiang Partridge Duck and part of body size traits can be improved by allele selection.展开更多
[ Objective] The study aimed to lay a foundation for the further studies on function mechanism of NS1 protein in the interspecies transmission of waterfowl influenza virus. [Method] Using the serologic assay and the s...[ Objective] The study aimed to lay a foundation for the further studies on function mechanism of NS1 protein in the interspecies transmission of waterfowl influenza virus. [Method] Using the serologic assay and the specific RT-PCR method, some strains of H9 subtype waterfowl influenza virus were isolated from the 12 to 20 day-old muscovy duck flocks without any clinical symptoms in different areas of Guangdong Province. Four of these strains, including A/duck/ZQ/303/2007（H9N2） （A3 for short）, A/Duck/FJ/301/2007 （H9N2） （C1 for short）, A/Duck/NH/306/2007（H9N2） （ D6 for short）, A/duck/SS/402/2007（H9N2） （ E2 for short）, and a strain named A/duck/ZC/2007（H9N2） （L1 for short） from a muscovy duck died of avian influenza virus （AIV）, were used for NSl gene cloning and sequencing. Subsequently, the obtained NSl gene sequences were compared with other NS1 sequences registered in GenBank, and the phylogenetic analysis was also conducted. [Result] When compared with the H9N2 AIV NS1 sequences in GenBank, the NSl genes of the four AIV strains A3, C1, 136 and E2 displayed homologies ranging from 99% to 100% at nucleotide level, and 95% to 100% at amino acid level; while the NSl gene of L1 strain displayed homology ranging from 94% to 97% at nucleotide level, and 93% to 98% at amino acid level. The phylogenetic tree demonstrated that A3, C1, D6 and E2 were highly resemblant, and L1 was closest to AY66473 （chicken, 2003）. By comparison with the NS1 gene sequences of L1, AF523514 （duck）, AY664743 （chicken） and EF155262.1 （quail） using DNAstar, A3, C1, D6 and E.2 presented nucleotide variations at site 21 （ R→Q）, 70, 71 （ KE→EG）, 86 （ A→S）, 124 （V→M） and 225 （ S→N）, and amino acid variations at site 21,70, 71 and 86 in dsRNA- dependent protein kinase （PKR） binding domain of NSl gene, which induced the evident variations of antigenic determinant and surface proba- bility plot of NS1 protein. [ Conclusion] This study suggested that the amino acid sequence variation in PKR binding domain of NS1 protein had something to do with the virus pathogenicity.展开更多
[Objeclive] The comparison of levels of thyroid hormones （T3, T4 and FT3） in female ducks serum and embryo of different embryonic age between Gaoyou duck and Jinding duck were made to provide basic data for further ...[Objeclive] The comparison of levels of thyroid hormones （T3, T4 and FT3） in female ducks serum and embryo of different embryonic age between Gaoyou duck and Jinding duck were made to provide basic data for further research. [Method] The levels of thyroid hormones （T3, T4 and FT3） in female ducks serum, fertilized eggs, and 7, 11,15, 19, 22, 28-days embryo of Gaoyou duck and Jinding duck were analyzed with radioimmunoassay （RIA）. [ Result]The levels of thyroid hormones in fertilized eggs were higher than those in serum of female ducks; different em- bryonic age hormone level of Gaoyou duck and Jinding duck in serum had almost the same variation trend, which was low but relatively stable after 15 days. [Condusion] The result suggested that thyroid hormones play an important role in duck embryonic development, especially in the early peded.展开更多
A severe egg-drop disease caused by the infection of a novel duck flavivirus outbroke successively in many provinces in southeastern China since 2010.It was identified as a duck Tembusu virus（DTMUV）and named by Chin...A severe egg-drop disease caused by the infection of a novel duck flavivirus outbroke successively in many provinces in southeastern China since 2010.It was identified as a duck Tembusu virus（DTMUV）and named by Chinese Association of Animal Science and Veterinary Medicine in the first symposium on waterfowl disease control,which was presumed to be a mosquito-borne flavivirus of the Ntaya virus subgroup in the genus Flavivirus,family Flaviviridae.Currently,a large number of studies have been conducted on the epidemiology,clinical symptoms and pathological changes,etiology,and rapid diagnoses of the virus.The disease remains a constant threat to the duck industry.In order to provide reference for subsequent in-depth study,in this paper,research progress on the disease was summarized based on previous studies.Furthermore,the potential infection or asymptomatic infection in humans should be evaluated as soon as possible.展开更多
A study was taken up on integration of ducks in private and community fish ponds in Tami Nadu. A total of 50 ha of land under private holding and community water bodies each were selected to implement this model. Duck...A study was taken up on integration of ducks in private and community fish ponds in Tami Nadu. A total of 50 ha of land under private holding and community water bodies each were selected to implement this model. Ducks were integrated based on the water spread area. Fodder, fruit, nuts, fuel, timber trees and vegetables were grown on pond bunds. Control units of fish ponds of farmers holding without integration of ducks also were taken up. A control unit also was established in the university farm land with and without integration of ducks. In private water bodies coconut trees and banana fetched additional revenue. During the first year the average fish production from the private land model was 1,552 kg and 1,731 kg for the first and second year respectively per Hectare. In community ponds the yields were 1,610 and 1,337 kg for the first and second year respectively. In field control units there was no increase in fish yield over the years. In private water bodies the beneficiaries got egg yield of 148 and 90 eggs and community water bodies 144 and 127 eggs per bird were obtained during first and second year resoectivelv.展开更多
文摘This article examines Chinese roast duck,with particular emphasis on Cantonese roast duck.It traces the origin of roast duck to the Northern and Southern Dynasties and describes its development through various dynasties.Roast duck played an important role in military,court,and folk life,and left evidence in many ancient books.The article introduces the preparation methods of Beijing,Nanjing,and Cantonese roast ducks.It analyzes the significance of Cantonese roast duck in Cantonese culinary culture and distinguishes roast duck from roast goose.It argues that Chinese roast duck,particularly Cantonese roast duck,is a distinguished and historically significant element of Chinese culinary culture,whose development reflects the evolution of regional cooking techniques,social customs,and cultural values from ancient times to the present.By tracing the origins,historical development,and cultural significance of roast duck,the article highlights its role as both a culinary symbol and a vehicle for understanding broader patterns of Chinese food culture,thereby contributing to the appreciation and global recognition of Chinese cuisine.
基金National Key Research and Development Program of China(2021YFC2103003)National Natural Science Foundation of China(31972604)+1 种基金Jinan Introductory Innovation Team Project(No.202228037)China Postdoctoral Science Foundation(2023M730998).
文摘Background AflatoxinB1(AFB_(1))is a prevalent contaminant in agricultural products,presenting significant risks to animal health.CotA laccase from Bacillus licheniformis has shown significant efficacy in degrading mycotoxins in vitro test.The efficacy of Bacillus CotA laccase in animals,however,remains to be confirmed.A 2×2 factorial design was used to investigate the effects of Bacillus CotA laccase level(0 or 1 U/kg),AFB_(1) challenge(challenged or unchal-lenged)and their interactions on ducks.The purpose of this study was to evaluate the efficacy of Bacillus CotA laccase in alleviatingAFB_(1) toxicosis of ducks.Results Bacillus CotA laccase alleviatedAFB_(1)-induced declines in growth performance of ducks accompanied by improved average daily gain(ADG)and lower feed/gain ratio(F/G).Bacillus CotA laccase amelioratedAFB_(1)-induced gut barrier dysfunctions and inflammation testified by increasing the jejunal villi height/crypt depth ratio(VH/CD)and the mRNA expression of tight junction protein 1(TJP1)and zonula occluden-1(ZO-1)as well as decreasing the expression of inflammation-related genes in the jejunum of ducks.Amino acid metabolome showed that Bacillus CotA laccase amelioratedAFB_(1)-induced amino acid metabolism disorders evidenced by increasing the level of glu-tamic acid in serum and upregulating the expression of amino acid transport related genes in jejunum of ducks.Bacil-lus CotA laccase amelioratedAFB_(1)-induced liver injury testified by suppressing oxidative stress,inhibiting apoptosis,and downregulating the expression of hepatic metabolic enzyme related genes of ducks.Moreover,Bacillus CotA laccase degradedAFB_(1) in digestive tract of ducks,resulting in the reduced absorption level ofAFB_(1) across intestinal epithelium testified by the decreased level ofAFB_(1)-DNA adduct in the liver,and the reduced content ofAFB_(1) residues in liver and feces of ducks.Conclusions Bacillus CotA laccase effectively improved the growth performance,intestinal health,amino acid metabolism and hepatic aflatoxin metabolism of ducks fedAFB_(1) diets,highlighting its potential as an efficient and safe feed enzyme forAFB_(1) degradation in animal production.
基金supported by the grants from the National Natural Science Foundation of China(31872497 and 32072844)the National Key Research and Development Program of China(2021YFD1800200 and 2016YFD0500207)the Laboratory of Lingnan Modern Agriculture Project,China(NT2021007)。
文摘TypeⅠinterferon(IFN)-mediated innate immune responses represent the first line of host defense against viral infection.However,the molecular mechanisms by which avian infuenza virus(AIV)inhibits typeⅠIFN production in ducks are not well understood.Here,we frst found that the polymerase basic 2(PB2)protein of H5N1 subtype AIV inhibited the typeⅠIFN responses by targeting duck mitochondrial antiviral signaling protein(MAVS).We further demonstrated that H5N1-PB2 bound to theΔtransmembrane(ΔTM)domain of duck MAVS,and the polymerase basic 1(PB1)binding domain(PBD)and RNA binding nuclear import domain(RND)of H5N1-PB2 interacted with MAVS to inhibit typeⅠIFN expression in ducks.Collectively,our fndings contribute to understanding the molecular mechanism by which AIV proteins regulate the retinoic acid-inducible geneⅠ(RIG-Ⅰ)-like receptor(RLR)signaling pathway to evade host antiviral immune responses in ducks.
基金financially supported by the National Natural Science Foundation of China(Grant No.32171528)Natural Science Foundation of Jiangsu Province(Grant No.BK20221180).
文摘Duck species are important vectors for seed dispersal of many plants,contributing significantly to the regeneration of wetland plant communities.However,research on the temporal changes in diet and the dynamics and differences of seed dispersal among different duck species is still limited.In this study,we analyzed the diversity of duck community and the diversity of seeds in the feces of different duck species from December to February for 2022–23 and 2023–24 in the coastal wetland of Dafeng,eastern Jiangsu Province,China.A total of 13 duck species were recorded in the four habitats,of which Spot-billed Ducks(Anas zonorhyncha)and Mallards(A.platyrhynchos)were the most abundant.The diversity and abundance of ducks vary across different habitats,and tidal flat supports the greatest diversity and abundance of ducks.We collected fecal samples from Spot-billed Ducks,Gadwalls(Mareca strepera),Mallards,and Eurasian Teals(A.crecca)in the tidal flat,from which seeds belonging to 7 families,13 genera and 15 different plant species were obtained.There were significant differences in seed dispersal among the four duck species,which varied with the season.Gadwalls and Common Teals showed more significant diversity in seed dispersal,with their feces containing a greater variety of plant seeds,which is related to their broader dietary range and ecological adaptability.Furthermore,the seasonal variation in the number of seeds per feces reflected the availability of seeds in the habitat and the response of ducks to environmental changes,while variations in seed intake among different duck species may be associated with inter-annual weather condition changes.The results of this study will provide a new perspective for understanding the mechanisms of bird-mediated seed dispersal in coastal wetland and offer preliminary insights for the seed dispersal by Asian ducks.
基金Supported by Key Project for Ministry of National Science and Tech-nique (2006BAD01A09)National 863 Project (2006AA10Z1D8)~~
文摘[Objective] The aim of this study was to investigate the development rule of muscle fiber in different duck breeds during various developmental stages. [Method] Cherry valley duck, Jinding duck, White muscory duck and Suma duck （ Cherry valley duck ♂ × Jinding duck ♀ ） were fed for 10 weeks to observe the ultrastructure of muscle fiber by electron microscope, and the myofibril diameter and sarcomere length were also determined. [Result] The myofibril diameter increased with ages. Sarcomere length and myofibril diameter did not change significantly with the increasing ages （P〉0.05）. The myofibril diameter of White muscory duck and Jinding duck were thicker, while that of Cherry valley cluck and Suma duck were thinner. Moreover, the sarcomere length of Suma duck and White muscory duck were longer, while that of Cherry valley duck and Jinding duck were shorter. Thus, the basic characteristics of ultrastructure of muscle fiber were consistent in these duck breeds.[Conclusion] The results have an important meaning for duck breeding.
基金Supported by National Agricultural Scientific and Technological Achievements Transformation Program of China(2012GB2C100165)~~
文摘[Objective] The aim was to improve the quality of the duck blood tofu by ultrasonic technology. [Method] Ultrasonic technology was used to break the blood cell membrane. The optimal ultrasonic condition was determined by single factor de- sign, and the differences in sensory quality and nutritional value between the duck blood tofu treated with and without ultrasonication were studied. [Result] The optimal ultrasonic power was 400 W and the optimal ultrasonic time was 6 min. Under these conditions, the content of duck blood haemoglobin increased by 43.46%, the content of iron increased by 10.85%, and the breakage rate was 100%. The a＊ value of the duck blood tofu increased significantly under ultrasonic treatment. Both internal micro-structure and texture parameters proved that the ultrasonic contributed to the formation of gel structure. After treatment by artificial gastric juice and artifi- cial intestinal juice, the total amino acids in the digestive juice were 9.25% higher than that of the duck blood tofu without ultrasonic treatment. [Conclusion] The duck blood tofu under ultrasonic treatment would be beneficial to human body absorption, and the nutrition value would be higher as well.
基金This work was supported by the National High-tech Research and Development Program (863 Program) (No. 2001AA243082)the National Natural Science Foundation of China (No. 30170673).
文摘Seventeen microsatellite loci were used to assess the genetic variation and population structure of six endangered duck populations in China. PIC, heterozygosity with two estimators of genetic differentiation （FST and GST）, and Nei＇s standard genetic distance were evaluated. The results showed that these six endangered duck populations showed high polymorphism. The propor- tion of inter-population subdivision among the six duck populations ranged between 17.0 and 14.7%. The average heterozygosity was 0.706, 0.702, 0.691, 0.676, 0.604, and 0.660 in the Gaoyou, Liancheng, Jinding, Beijing, Shaoxing, and Jianchang ducks, respectively. The average PIC ranged from 0.561 to 0.663. Finally, the results showed higher genetic diversity and difference above the levels of genetic variation among all the populations.
基金Supported by Project of Jiangsu Agri-animal Husbandry Vocational College(NSFZN1309)~~
文摘In order to investigate the effects of probiotics on growth performance, blood biochemical indexes and economic benefits of Cherry Valley ducks, different probiotics were added into the feed of Cherry Valley ducks. Total 240 1-d-old Cherry Valley ducks were selected, and they were randomly divided into 4 groups, including 1 control group and 3 treatment groups. There were 3 replicates for each group and there were 20 ducks for each replicate. The ducks in the control group were fed the basal diet, and the ducks in the 3 treatment groups were fed the basal diet added with Lactobacillus, Bacillus natto and florfenicol, respectively. The test lasted for 42 d. The results showed that the addition of Lactobacillus and Bacillus natto could improve the average daily weight gain and final average weight （P〈0.05） of Cherry Valley ducks, and reduce the glutamic-pyruvic transaminase ac- tivity, alkaline phosphatase activity and serum urinary nitrogen content in duck blood （P〈0.05） and reduce the creatinine content and total cholesterol content in Cherry Valley ducks （P〉0.05）; at the same time, adding probiotics to feed could also in- crease the grass economic benefits of Cherry Valley ducks. In overall, the effects of adding probiotics were better than those of adding antibiotic.
基金supported by Natural Science Foun-dation of Hebei Province (D2006000701, C2007000247)Doctoral Fund of Hebei Normal University (L2008B11)
文摘A new breeding population of Mandarin Duck （Aix gaIericulata, Linnaeus） was first recorded in 2003 in Jiao- tanzhuang-Hehekou region of Pingshan county, Hebei Province, China. Recently, the gradually increasing population indicates that there are suitable breeding habitats （such as foraging habitats and nesting sites） for Mandarin Duck. However, these habitats are always close to human disturbances, which are the potential risk for their population. Therefore, it is urgent to put forward an applicable protection strategy, in order to strengthen the public awareness for this unprotected population.
基金the grant of Shandong Province Higher Educational Science and Technology Program (J08LF07)Shandong Provincial Natural Sciences Fund (Q2006D04)
文摘To investigate molecular epidemiology of DuCV in Cherry Valley ducks in China, the complete genomes of six DuCV strains, which were detected from Cherry Valley ducks in China between 2007 and 2008, were sequenced. Sequence and phylogenetic analysis were carried out to compare these six strains with another 27 DuCV strains from Mulard duck, Muscovy duck, Pekin ducks and Mule duck. The analysis showed that the six DuCV strains exhibited typical genetic features of the family of DuCV, such as a stem-loop structure, three major open reading frames (Rep, Cap and ORF3), four intergenic repeats and the conserved motifs for rolling circle replication and for the dNTP binding domain located in the Rep protein. Phylogenetic analysis of the nucleotide sequences of the complete genome and Cap gene of these strains together with those that have been previously published demonstrated two distinct DuCV genotypes. The DuCV strains with complete genomes containing 1988 and 1989 nucleotides clustered in genotype A, whereas the strains with complete genomes containing 1991, 1992, 1995 and 1996 nucleotides lay in genotype B. The six DuCV strains from Cherry Valley ducks were divided into the two groups. The results of the study provides some insight into the variation of DuCVs in Cherry Valley ducks.
基金the National Natural Science Foundation of China (No. 30471533)
文摘To examine the effect of Gankang Suppository on duck hepatitis B virus （DHBV）, the serum biochemistry and hepatic histology in an animal model of DHBV infection, a model of DHBV infection was established by infecting 1-day-old Yingtaogu ducklings with DHBV-positive serum. The successful model was confirmed by PCR assay and 48 ducklings infected with DHBV were randomly divided into 3 groups： a Gankang Suppository treatment group, an acyclovir （ACV） group and a DHBV model group （control）, with each group having 16 animals. All the animals were given the medicines for 4 weeks in a row. The serum of the animals was taken 14 and 28 days after the medica- tion and 7 days after drug discontinuation. Real-time PCR was performed to detect the copy numbers of DHBV DNA in the serum. ALT and AST were dynamically monitored. The ducklings were sacrificed on the 7th day after the discontinuation of the treatment and livers were harvested and examined for inflammation and degeneration of liver cells by using HE staining. The results showed that on day 14, 28 after the treatment and day 7 after the withdrawal, the logarithmic values （log） of DHBV DNA copy numbers in ducklings of Gankang Suppository treatment group were significantly lower than that before the treatment （P=0.0092, P=0.0070, P=0.0080, respectively）. Compared with DHBV model control group, the ALT level was significantly decreased （P=0.0020, P=0.0019, respectively） on day 28 after the treatment and on day 7 after the withdrawal. The AST level was also reduced on day 14 after the treatment （P=0.0298）. Compared with the ACV control group, the level of ALT was lower on day 7 after the withdrawal （P=0.0016）. Histologically, the hepatocyte swelling, vacuolous degeneration and acidophilic degeneration in Gankang Suppository treatment group were alleviated 7 days after the withdrawal as compared with model control group （P=0.0282, P=0.0084, P=0.0195, respectively）. It is concluded that Gankang Suppository can effectively suppress DHBV replication, reduce the levels of serum ALT and AST and improve hepatic histology.
基金the National Special Funds of System of Industrial Technologies for Modern Agriculture of China(nycytx-45-04)
文摘Twelve fluorescence-labeled microsatellite markers were used to analyze the genetic diversity of 12 domestic duck breeds and 2 wild duck breeds to determine the relationship and origin of Chinese domestic duck breeds. Gene frequency, effective number of alleles （Ne）, expected heterozygosity （He）, polymorphism information contents （PIC）, inbreeding coefficient in population （Fis）, standard genetic distance （Ds）, and genetic distance （DA） were calculated by FSTAT and distance and phylogenetic analysis after the dates which were output from the Microsatellite-Toolkit software. Genetic distances between 12 domestic duck breeds and 2 wild duck breeds were analyzed by variance analysis. Unweighted pair group method with arithmetic mean （UPGMA） and phylogenetic trees used for cluster analysis were structured. The results indicated that 11 loci had medium- or high-level genetic diversity among the 12 loci, which could be efficiently used in the detection of the genetic parameters of each population. The values of He were 0.5414 to 0.7343, those of PIC proved similar, and those of Fis were 0.1101 to 0.3381 among all populations. All breeds were clustered into three groups by UPGMA phylogenetic trees. Banzui duck was clustered into a separate group. Differences of the DA were analysed by t-test. The results showed that difference in DA between the 12 domestic duck breeds and Lvtou duck and the Banzui duck were very significant （P〈0.01）, indicating that these 12 domestic duck breeds originated from Lvtou wild duck, but not Banzui duck.
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.
基金Supported by Science and Technology Development of Hubei Province during the Eleventh Five-Year Plan Period (2006AA202A04)~~
文摘[Objective]The research aimed to study the polymorphism of intron 1 and its effects on prolactin（PRL） gene and body size traits of Jingjiang Partridge Duck.[Method]Taking 96 Jingjiang partridge ducks as materials,the polymorphism of intron 1 of PRL gene was detected by PCR-RFLP method.And the relationship between the gene polymorphism and body size traits was analyzed.[Result]Intron 1 in PRL gene of Jingjiang Partridge Duck had sequence polymorphism.Two kinds of genotypes（AB and BB） were detected by DraⅠrestriction and genotype BB was dominant in population（91.67%）.The results of Chi-square test indicated that this site was in Hardy-Weinberg equilibrium in Jingjiang Duck（P 〉0.05）.The results of least square analysis showed that the ducks with AB genotype had larger pelvis breadth（P 〈0.01） but smaller chest measurement（P 〈0.05） than those of BB ducks.[Conclusion]It was preliminarily concluded that PRL gene could be regarded as useful candidate gene（marker） for part of body size traits of Jingjiang Partridge Duck and part of body size traits can be improved by allele selection.
基金Supported by Key Specific Program for Science and Technology of Guangdong Province (2008B020700003 A2007A020400006)~~
文摘[ Objective] The study aimed to lay a foundation for the further studies on function mechanism of NS1 protein in the interspecies transmission of waterfowl influenza virus. [Method] Using the serologic assay and the specific RT-PCR method, some strains of H9 subtype waterfowl influenza virus were isolated from the 12 to 20 day-old muscovy duck flocks without any clinical symptoms in different areas of Guangdong Province. Four of these strains, including A/duck/ZQ/303/2007（H9N2） （A3 for short）, A/Duck/FJ/301/2007 （H9N2） （C1 for short）, A/Duck/NH/306/2007（H9N2） （ D6 for short）, A/duck/SS/402/2007（H9N2） （ E2 for short）, and a strain named A/duck/ZC/2007（H9N2） （L1 for short） from a muscovy duck died of avian influenza virus （AIV）, were used for NSl gene cloning and sequencing. Subsequently, the obtained NSl gene sequences were compared with other NS1 sequences registered in GenBank, and the phylogenetic analysis was also conducted. [Result] When compared with the H9N2 AIV NS1 sequences in GenBank, the NSl genes of the four AIV strains A3, C1, 136 and E2 displayed homologies ranging from 99% to 100% at nucleotide level, and 95% to 100% at amino acid level; while the NSl gene of L1 strain displayed homology ranging from 94% to 97% at nucleotide level, and 93% to 98% at amino acid level. The phylogenetic tree demonstrated that A3, C1, D6 and E2 were highly resemblant, and L1 was closest to AY66473 （chicken, 2003）. By comparison with the NS1 gene sequences of L1, AF523514 （duck）, AY664743 （chicken） and EF155262.1 （quail） using DNAstar, A3, C1, D6 and E.2 presented nucleotide variations at site 21 （ R→Q）, 70, 71 （ KE→EG）, 86 （ A→S）, 124 （V→M） and 225 （ S→N）, and amino acid variations at site 21,70, 71 and 86 in dsRNA- dependent protein kinase （PKR） binding domain of NSl gene, which induced the evident variations of antigenic determinant and surface proba- bility plot of NS1 protein. [ Conclusion] This study suggested that the amino acid sequence variation in PKR binding domain of NS1 protein had something to do with the virus pathogenicity.
基金funded by State Funds($31172194)Jiangsu Province Modern Agricultural Variety Innovation CX(11)(1030)+1 种基金Science and Technology Support Plan(BE2011329)Yangzhou City Science and Technology Research(YZ2010048)
文摘[Objeclive] The comparison of levels of thyroid hormones （T3, T4 and FT3） in female ducks serum and embryo of different embryonic age between Gaoyou duck and Jinding duck were made to provide basic data for further research. [Method] The levels of thyroid hormones （T3, T4 and FT3） in female ducks serum, fertilized eggs, and 7, 11,15, 19, 22, 28-days embryo of Gaoyou duck and Jinding duck were analyzed with radioimmunoassay （RIA）. [ Result]The levels of thyroid hormones in fertilized eggs were higher than those in serum of female ducks; different em- bryonic age hormone level of Gaoyou duck and Jinding duck in serum had almost the same variation trend, which was low but relatively stable after 15 days. [Condusion] The result suggested that thyroid hormones play an important role in duck embryonic development, especially in the early peded.
基金Supported by Natural Science Foundation of Shandong Province(ZR2012CQ012)Special Fund for Applied Technology Research and Development of Binzhou City(200706)Technological Innovation Project of Shandong Province(201220916006)
文摘A severe egg-drop disease caused by the infection of a novel duck flavivirus outbroke successively in many provinces in southeastern China since 2010.It was identified as a duck Tembusu virus（DTMUV）and named by Chinese Association of Animal Science and Veterinary Medicine in the first symposium on waterfowl disease control,which was presumed to be a mosquito-borne flavivirus of the Ntaya virus subgroup in the genus Flavivirus,family Flaviviridae.Currently,a large number of studies have been conducted on the epidemiology,clinical symptoms and pathological changes,etiology,and rapid diagnoses of the virus.The disease remains a constant threat to the duck industry.In order to provide reference for subsequent in-depth study,in this paper,research progress on the disease was summarized based on previous studies.Furthermore,the potential infection or asymptomatic infection in humans should be evaluated as soon as possible.
文摘A study was taken up on integration of ducks in private and community fish ponds in Tami Nadu. A total of 50 ha of land under private holding and community water bodies each were selected to implement this model. Ducks were integrated based on the water spread area. Fodder, fruit, nuts, fuel, timber trees and vegetables were grown on pond bunds. Control units of fish ponds of farmers holding without integration of ducks also were taken up. A control unit also was established in the university farm land with and without integration of ducks. In private water bodies coconut trees and banana fetched additional revenue. During the first year the average fish production from the private land model was 1,552 kg and 1,731 kg for the first and second year respectively per Hectare. In community ponds the yields were 1,610 and 1,337 kg for the first and second year respectively. In field control units there was no increase in fish yield over the years. In private water bodies the beneficiaries got egg yield of 148 and 90 eggs and community water bodies 144 and 127 eggs per bird were obtained during first and second year resoectivelv.
