Embden Goose Research Articles

Role of Poultry in the Spread of Novel H7N9 Influenza Virus in China

The recent outbreak of H7N9 influenza in China has resulted in many human cases with a high fatality rate. Poultry are the likely source of infection for humans on the basis of sequence analysis and virus isolations from live bird markets, but it is not clear which species of birds are most likely to be infected and shedding levels of virus sufficient to infect humans. Intranasal inoculation of chickens, Japanese quail, pigeons, Pekin ducks, Mallard ducks, Muscovy ducks, and Embden geese with 10(6) 50% egg infective doses of the A/Anhui/1/2013 virus resulted in infection but no clinical disease signs. Virus shedding was much higher and prolonged in quail and chickens than in the other species. Quail effectively transmitted the virus to direct contacts, but pigeons and Pekin ducks did not. In all species, virus was detected at much higher titers from oropharyngeal swabs than cloacal swabs. The hemagglutinin gene from samples collected from selected experimentally infected birds was sequenced, and three amino acid differences were commonly observed when the sequence was compared to the sequence of A/Anhui/1/2013: N123D, N149D, and L217Q. Leucine at position 217 is highly conserved for human isolates and is associated with α2,6-sialic acid binding. Different amino acid combinations were observed, suggesting that the inoculum had viral subpopulations that were selected after passage in birds. These experimental studies corroborate the finding that certain poultry species are reservoirs of the H7N9 influenza virus and that the virus is highly tropic for the upper respiratory tract, so testing of bird species should preferentially be conducted with oropharyngeal swabs for the best sensitivity. The recent outbreak of H7N9 influenza in China has resulted in a number of human infections with a high case fatality rate. The source of the viral outbreak is suspected to be poultry, but definitive data on the source of the infection are not available. This study provides experimental data to show that quail and chickens are susceptible to infection, shed large amounts of virus, and are likely important in the spread of the virus to humans. Other poultry species can be infected and shed virus but are less likely to play a role of transmitting the virus to humans. Pigeons were previously suggested to be a possible source of the virus because of isolation of the virus from several pigeons in poultry markets in China, but experimental studies show that they are generally resistant to infection and are unlikely to play a role in the spread of the virus.

Research Note: Avian Leukosis Retroviral Genes are not Detected in Geese

Genomic DNA from four strains of geese was analyzed for the presence of endogenous viral elements using a probe that can detect over 20 Rous-associated endogenous viral genes (ev genes) in chickens, as well as a probe and protocol that detects endogenous avian viruses (EAV). Southern blot analysis of genomic DNA did not reveal any ev genes in DNA of 15 geese from Chinese, Synthetic, or two Embden goose strains. Even under low stringency conditions, using a probe that covered most of the polymerase (pol) gene of the Rous-associated virus (RAV) and that revealed EAV elements in a chicken without ev genes, no viral loci were evident in goose DNA.

Common antigenic properties of a g-type (goose) and a c-type (duck) egg white lysozyme: Antibody responses in rabbits and mice

Embden goose (GEWL) and Barbary duck (DEWL) egg white lysozymes possess different amino acid sequences corresponding to the g-type and c-type, respectively. GEWL was shown to be a better immunogen than DEWL in both rabbits and mice. The antigenicity of the two lysozymes was tested using different techniques (i.e. indirect ELISA, inhibition tests and immunoabsorption experiments). Injection of either GEWL or DEWL into rabbits and mice induced both specific antibodies and cross-reacting antibodies. Moreover, anti-GEWL antibodies, in contrast to anti-DEWL antibodies, did not cross-react with hen egg white lysozyme (HEWL), a c-type lysozyme. While the structure of GEWL was not modified after binding to plastic, DEWL was denaturated, but it did keep some native epitopes. It was concluded that g-type and c-type lysozymes, which have different amino acid sequences, exhibit strong common antigenic properties.

Three-dimensional Structure of Goose-type Lysozyme from the Egg White of the Australian Black Swan, Cygnus atratus

The egg white of C. atratus contains two forms of lysozyme, a 'chick-type' which is similar to that found in the egg white of the domestic hen, and a 'goose-type' similar to that found in the egg white of the Embden goose. The molecular structure of the goose-type lysozyme has been determined at a resolution of a 2.8 A by X-ray crystallographic analysis. The structure consists of two domains linked by a long stretch of alpha-helix. In all, there are seven helical segments in the structure. While there is no amino acid sequence homology with either hen egg-white or bacteriophage T4 lysozymes, there are portions of the structure where the folding of the main chain is similar to that found in portions of either hen egg-white lysozyme or T4 lysozyme or both. In particular, there is a consistency of structure in the arrangement of acid groups in the catalytic site. G-o plots calculated for this structure and for the bacteriophage T4 lysozyme structure show that both have similar 'modules' of structure with boundaries occurring at structurally equivalent positions. Three of the common boundaries are equivalent structurally to three of the four module boundaries observed in G-o plots of hen egg-white lysozyme. The variation in the position of the remaining boundary may be related to differences in substrate binding.

Complete amino acid sequence of Embden goose ( Anser anser) egg-white lysozyme

The complete amino acid sequence of Embden goose ( Anser anser) egg-white lysozyme (EC 3.2.1.17) has been proposed. The structure was established by comparing the citraconylated tryptic peptides of Embden goose lysozyme with the corresponding peptides from the black swan goose-type lysozyme. Those peptides which differed in amino acid composition were subjected to sequence analysis; the alignment of the tryptic peptides was achieved by analogy with other goose-type lysozymes. Embden goose lysozyme is a single polypeptide chain of 185 amino acids. It closely resembles the goose-type lysozymes from the black swan and the ostrich, differing in 6 and 30 residues, respectively.

Crystallographic data for lysozyme from the egg white of the embden goose

Two crystal forms of lysozyme from the egg white of the embden goose ( Anser anser) have been obtained, both of which are suitable for X-ray diffraction analysis. The monoclinic form has space group P2 1 with cell dimensions a = 38.3 A ̊ , b = 65.7 A ̊ , c = 45.2 a ̊ , β = 116 ° and the triclinic form (space group P1) has cell dimensions of a = 39.9 A ̊ , b = 42.2 A ̊ , c = 57.9 A ̊ and α = 98.8 °, β = 102.5 °, γ = 90.5 °.

Evidence of Influenza Viruses in Guinea Hens and White Embden Geese

Serologic evidence of infection with influenza A viruses is reported in commercially raised guinea fowl and White Embden geese in Minnesota.

Multiple Genes for Lysozyme in Birds: Studies on Black Swan Egg White Lysozymes

In contrast to other bird species that have been studied, not one but two distinct lysozymes have been isolated from the egg white of the black swan (Cygnus atratus). One is similar in molecular weight, NH2-terminal amino acid sequence, amino acid composition, specific activity, and immunological cross-reactivity to the lysozymes found in the egg white of the chicken, duck, and many other birds. The other black swan lysozyme shows no resemblance to these “chick-type” enzymes by the above criteria. It is very similar to the lysozyme found until now only in the egg white of the Embden goose. This black swan lysozyme and Embden goose lysozyme have a molecular weight of about 20,500 and are identical in the sequence of their first 20 NH2-terminal amino acids and in immunological cross-reactivity. Amino acid composition data indicate that these two “goose-type” lysozymes differ in sequence by a minimum of four amino acid substitutions. The differences in the structures of the chick-type and goose-type lysozymes suggest that they are products of two distinct genetic loci. Some species contain only chick-type lysozymes in their egg white (e.g. chicken, duck), others only goose-type lysozymes (Embden goose), while others contain both types of enzyme (black swan). In the light of other evidence, this suggests that the genetic loci coding for both enzymes are present in all species and that the presence of either or both lysozymes in egg white is controlled by a species-specific regulatory mechanism.

Multiple genes for lysozyme in birds

Quantitative microcomplement-fixation and immunodiffusion studies using antisera prepared against purified chicken and Embden goose lysozymes indicate that two lysozymes are present in black swan ( Cygnus atratus) egg white. Their different antigenic structures suggest that these two forms of lysozyme may be the products of nonallelic genes. The possibility of multiple gene loci for lysozyme or other proteins calls for caution in the interpretation of data on the rate of protein evolution.

Studies of Reproduction in Ducks: 1. The Duration of Fertility and Hatchability of White Pekin Duck Eggs

THE DURATION of fertility in domestic birds of the order Galliformes has been the subject of much experimentation, but relatively few studies are known for those of the order Anseriformes. Using the latter the maximum duration following artificial insemination was found to be 16 days in Pilgrim geese (Johnson, 1954) and 14 days in Embden geese (Kinney and Burger, 1960).A maximum duration of fertility of 13 days was recorded in the Philippines by Fronda et al. (1940) for native ducks and by Tolentino (1948) for Muscovies. Elder and Weller (1954) obtained fertile eggs from wild Mallards 17 days after isolation of females. Watanabe and Sugimori (1957), using artificial insemination, found a maximum duration of 12 days in the Japanese Ōsaka duck. Subsequently Watanabe (1959), again using artificial insemination, found the statistic to be 7 days for Ōsaka females receiving semen from either Ōsaka or Muscovy drakes. Landau and Vančíková …