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PubMed2003

Comparison of the immune responses against Salmonella enterica serovar Gallinarum infection between naked neck chickens and a commercial chicken line.

The immune responses of indigenous naked neck (NaNa and Nana) and normally feathered (nana) chickens against a Salmonella Gallinarum (SG) infection were evaluated and compared with those of a commercial line (B-380). Groups of 28-day-old chickens (NaNa, Nana, nana, and B-380) were immunized orally and subcutaneously with 50 microg of SG antigens. Control non-immunized animals were inoculated with sterile saline solution. All chickens were challenged with 1 LD(50) of SG and mortality was recorded daily for 20 days. Antibodies to SG were measured in sera before immunization, before the challenge, 10 days after the challenge, and at sacrifice. Peripheral blood lymphocyte proliferation assays were performed using concanavalin A and SG antigens. Results showed that non-immunized Nana chickens exhibited the best natural resistance to Salmonella infection, since only 30% of them died. In contrast, all control B-380 chickens died by the 13th day. Immunization with SG induced immunity in chickens of all genotypes. Indigenous naked neck and normally feathered chickens showed a higher survival rate when compared with B-380 chickens. Immunized Nana chickens showed the highest antibody titres (P<0.05) as well as the highest thymidine incorporation in peripheral blood lymphocytes stimulated with con A or SG antigens (P<0.05). The results show that Nana chickens are the most resistant to SG infection and the best responders to vaccination with SG antigens.

Administration, Oral↗
PubMed1986

Isolation and determination of the amino acid sequence of chicken calcitonin I from chicken ultimobranchial glands.

A radioimmunoassay for chicken calcitonin in chicken ultimobranchial glands was established utilizing a rabbit antiserum against eel calcitonin. This assay method, which is about 100 times as sensitive as the usual bioassay for hypocalcemic activity, was used for monitoring chicken calcitonin during its purification. The immunoreactivity in chicken ultimobranchial extract was separated by SP-Sephadex C-25 chromatography into two fractions. Chicken calcitonin I, which was occurred in the major immunoreactive fraction, was further purified to homogeneity as shown by reverse phase HPLC. In the end, 39 nmol of chicken calcitonin I was obtained from 3,384 chickens following a 12,000-fold purification. The complete amino acid sequence of purified chicken calcitonin I was determined to be H-Cys-Ala-Ser-Leu-Ser-Thr-Cys-Val-Leu-Gly-Lys-Leu-Ser-Gln-Glu-Leu-His-Ly s-Leu-Gln-Thr-Tyr-Pro-Arg-Thr-Asp-Val-Gly-Ala-Gly-Thr-Pro-NH2 and confirmed by synthesis. The specific biological activity of chicken calcitonin I (4,500 MRCU/mg) was identical to that of eel calcitonin, which has the highest specific biological activity among the calcitonins so far isolated. Chicken calcitonin I resembled the calcitonins from the ultimobranchial glands both of salmon and eel in sequence, biological activity, and immunological property.

Amino Acid Sequence↗
PubMed2004

Survival of cold-stressed Campylobacter jejuni on ground chicken and chicken skin during frozen storage.

Campylobacter jejuni is prevalent in poultry, but the effect of combined refrigerated and frozen storage on its survival, conditions relevant to poultry processing and storage, has not been evaluated. Therefore, the effects of refrigeration at 4 degrees C, freezing at -20 degrees C, and a combination of refrigeration and freezing on the survival of C. jejuni in ground chicken and on chicken skin were examined. Samples were enumerated using tryptic soy agar containing sheep's blood and modified cefoperazone charcoal deoxycholate agar. Refrigerated storage alone for 3 to 7 days produced a reduction in cell counts of 0.34 to 0.81 log10 CFU/g in ground chicken and a reduction in cell counts of 0.31 to 0.63 log10 CFU/g on chicken skin. Declines were comparable for each sample type using either plating medium. Frozen storage, alone and with prerefrigeration, produced a reduction in cell counts of 0.56 to 1.57 log10 CFU/g in ground chicken and a reduction in cell counts of 1.38 to 3.39 log10 CFU/g on chicken skin over a 2-week period. The recovery of C. jejuni following freezing was similar on both plating media. The survival following frozen storage was greater in ground chicken than on chicken skin with or without prerefrigeration. Cell counts after freezing were lower on chicken skin samples that had been prerefrigerated for 7 days than in those that had been prerefrigerated for 0, 1, or 3 days. This was not observed for ground chicken samples, possibly due to their composition. C. jejuni survived storage at 4 and -20 degrees C with either sample type. This study indicates that, individually or in combination, refrigeration and freezing are not a substitute for safe handling and proper cooking of poultry.

Animals↗
PubMed2004

Mean total arsenic concentrations in chicken 1989-2000 and estimated exposures for consumers of chicken.

The purpose of this study was to estimate mean concentrations of total arsenic in chicken liver tissue and then estimate total and inorganic arsenic ingested by humans through chicken consumption. We used national monitoring data from the Food Safety and Inspection Service National Residue Program to estimate mean arsenic concentrations for 1994-2000. Incorporating assumptions about the concentrations of arsenic in liver and muscle tissues as well as the proportions of inorganic and organic arsenic, we then applied the estimates to national chicken consumption data to calculate inorganic, organic, and total arsenic ingested by eating chicken. The mean concentration of total arsenic in young chickens was 0.39 ppm, 3- to 4-fold higher than in other poultry and meat. At mean levels of chicken consumption (60 g/person/day), people may ingest 1.38-5.24 microg/day of inorganic arsenic from chicken alone. At the 99th percentile of chicken consumption (350 g chicken/day), people may ingest 21.13-30.59 microg inorganic arsenic/day and 32.50-47.07 microg total arsenic/day from chicken. These concentrations are higher than previously recognized in chicken, which may necessitate adjustments to estimates of arsenic ingested through diet and may need to be considered when estimating overall exposure to arsenic.

Age Factors↗
PubMed1977

Immunological capacity of the chicken embryo. II. Humoral immune responses in embryos and young chickens bursectomized and sham-bursectomized at 52--64 h of incubation.

White Rock embryos surgically "bursectomized" at 52--64 h of incubation, and shambursectomized embryos were injected with 10(6) guinea-pig red blood cells on day 12 of incubation, and tested for plaque-forming cells and serum haemagglutinins 3, 5, 7, 10, 15 and 19 days after immunization, i.e. as 15- to 19-day-old embryos and 1- to 10-day-old chickens. The number of natural plaque-forming cells detected by direct or indirect techniques was small in nonimmunized shambursectomized and bursectomized embryos, but increased in very young chickens. The injection of guinea-pig red blood cells induced a significant increase in the number of direct and indirect plaque-forming cells in the spleen of bursectomized and sham-bursectomized embryos and chickens. Agglutination of papain-treated guinea-pig red blood cells and indirect anti-chicken globulin (Coombs) test revealed the presence of natural agglutinins for guinea-pig and for sheep erythrocytes in non-immunized sham-and bursectomized embryos. A small number of sera from nonimmunized bursectomized and sham-bursectomized embryos contained IgM. The immunization with guinea-pig red blood cells increased the antibody production in both bursectomized and sham-bursectomized embryos and chickens. Sham-bursectomized embryos responded better to antigenic stimulation than bursectomized embryos. The injection of guinea-pig red blood produced an enlargement of the spleen only in bursectomized embryos and chickens. The first plasma cells appeared in nonimmunized sham-and bursectomized 6-day-old chickens. The number of plasma cells increased in chickens immunized as embryos. Cytomorphological analysis of the thymus, bone marrow and liver did not reveal apparent differences between bursectomized, sham-bursectomized embryos and very young chickens. It has been postulated that the chicken embryo has an antibody-producing system composed of the bursal and the nonbursal (or accessory "bursal") microenvironment, the latter being bursa-independent. The final microenvironmental network for the formation of Bu lymphocytes is the result of coordinated activities of a variety of intrinsic cellular and humoral factors.

Animals↗
PubMed1988

Lethality and bone alterations in chicken embryos and newly hatched chickens given bone-active agents.

Studies were undertaken to assess the chicken embryo and newly hatched chicken as models for studying the effects of bone-active agents. Initially, 1,25-dihydroxycholecaliferol (1,25[OH]2D3), sodium fluoride (NaF), parathyroid extract, epidermal growth factor, and prostaglandin E2, were tested for lethality over a broad dose range. One or 3 injections of 1,25(OH)2D3 into the yolk sac of chicken embryos resulted in death of embryos given greater than or equal to 0.1 ng/injection, whereas 0.01 ng was tolerated by the embryos. Administering 1,25(OH)2D3 intraperitoneally to newly hatched chickens as a single injection or weekly for 3 weeks resulted in no deaths at doses up to 50 ng. One or 3 IV injections of 800 micrograms of NaF were lethal to embryos, whereas injections of less than or equal to 400 micrograms were tolerated by the embryo. Giving chickens feed and water containing 2.4 g of NaF/kg was lethal, but no deaths occurred when chickens were given feed containing less than or equal to 1.2 g of NaF/kg. Mortality associated with the administration of epidermal growth factor to embryos was inconsistent, in that death occurred in embryos given a single injection of greater than or equal to 250 ng, but no deaths occurred in embryos given 3 injections at similar doses. Parathyroid extract and prostaglandin E2 were not lethal when administered to embryos and chickens in a single-injection or multiple-injection regimen. Overall, lethality in chicken embryos given a particular agent reflected the dose of bone-active agent injected, rather than the number of injections. Three of the bone-active agents were selected to characterize their microscopic bone effects in chicken embryos and chickens.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2006

The anti-nuclease humoral immune response of broiler chickens exposed to Staphylococcus aureus, infectious bursal disease virus and chicken anaemia virus in an experimental model for bacterial chondronecrosis and osteomyelitis.

This study aimed to develop an enzyme-linked immunosorbent assay to detect antibody associated with Staphylococcus aureus that is produced during the chicken immune response to this organism. The protein nuclease was tested for suitability as an antigen to detect antibody in sera from broiler chickens that had been exposed to aerosolized S. aureus on day 1 post hatch during experiments to reproduce bacterial chondronecrosis and osteomyelitis. An enzyme-linked immunosorbent assay was developed to measure the levels of nuclease antibody in 509 chicken sera from various experiments, which also enabled the examination of the influence of factors such as the S. aureus infection status and co-infection with chicken anaemia virus (CAV) and infectious bursal disease virus (IBDV) on nuclease antibody levels. Positive levels of nuclease antibody were detected in 71% of serum samples from chickens inoculated with S. aureus, CAV and IBDV, while positive levels were detected in 35% of chickens inoculated with S. aureus only. The influence of CAV and IBDV on the number of chickens with positive levels was most prominent in chickens aged up to 42 days. The study showed that nuclease-specific antibodies form part of the humoral immune response in broiler chickens that have been exposed to S. aureus. Co-infection with CAV and IBDV appeared to promote development of antibody in birds younger than 42 days; however, the presence of antibody did not necessarily prevent systemic infection.

Aging↗
PubMed2001

cDNA cloning of the chicken branched-chain alpha-keto acid dehydrogenase complex. Chicken-specific residues of the acyltransferase affect the overall activity and the interaction with the dehydrogenase.

Branched-chain alpha-keto acid dehydrogenase complex is a macromolecule comprising three catalytic components: a dehydrogenase (E1) with alpha(2)beta(2) structure, an acyltransferase (E2) and a dihydrolipoamide dehydrogenase (E3). In the mammalian complex, the E2 component with 24 identical subunits forms a structural core, to which multiple copies of E1 and E3 bind noncovalently. We isolated cDNA clones encoding E1 alpha, E1 beta and E2 subunits from a chicken-liver cDNA library and performed nucleotide sequencing. Amino-acid sequences deduced from the nucleotide sequences revealed that chicken E1 alpha and E1 beta chains had substantially homologous sequences with the corresponding mammalian polypeptides, except for the N-terminus. Chicken E2 conserved three functional domains, a lipoyl-bearing domain, an E1/E3 binding domain and an inner-core domain, but contrasted strongly with mammalian E2 in respect of containing 11 additional residues in two interdomain linkers: nine sequential residues in one linker and two residues in the other. Replacement of many residues was also observed in the chicken linkers. When E2 activity for catalyzing the overall reaction was measured by activity reconstitution in combination with E1 and E3, chicken E2 was markedly less effective than mammalian E2. The capability of chicken E2 for binding E1 was also reduced when determined by the binding assay using sucrose density gradient centrifugation. Chicken E1 was functionally as well as structurally indistinguishable from mammalian E1. Thus the reduced catalytic activity of chicken E2 must arise from its reduced E1-binding capacity, which results from the characteristic structure of interdomain linkers in chicken E2.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗
PubMed1992

Abdominal adipose tissue from broiler chickens selected for body weight or for food efficiency differ in in vitro lipolytic sensitivity to glucagon and to chicken growth hormone, but not to dibutyryl cAMP.

1. Differences in responses to lipolytic agents have been investigated in vitro in abdominal adipose tissue from lines of broiler chickens selected for body weight (GL, a 'fat' line) or for food efficiency (FC, a 'lean' line). 2. Dibutyryl cyclic adenosine monophosphate stimulated in vitro lipolysis, as measured by the glycerol release, by adipose tissue from GL or from FC chickens to the same extent. 3. Glucagon stimulated glycerol release from adipose tissue from FC chickens, but not from GL chickens. 4. Adipose tissue from GL chickens was much more sensitive to chicken growth hormone (GH) compared to FC chickens. 5. It is concluded that the selection criteria applied influenced the number of adipose GH and glucagon receptors, the number of adipose GH receptors being lower and of glucagon receptors being higher in FC chickens compared to GL chickens.

Abdomen↗
PubMed2006

Progress from chicken genetics to the chicken genome.

The chicken has a proud history, both in genetic research and as a source of food. Here we attempt to provide an overview of past contributions of the chicken in both arenas and to link those contributions to the near future from a genetic perspective. Companion articles will discuss current poultry genetics research in greater detail. The chicken was the first animal species in which Mendelian inheritance was demonstrated. A century later, the chicken was the first among farm animals to have its genome sequenced. Between these firsts, the chicken remained a key organism used in genetic research. Breeding programs, based on sound genetic principles, facilitated the global emergence of the chicken meat and egg industries. Concomitantly, the chicken served as a model whose experimental populations and mutant stocks were used in basic and applied studies with broad application to other species, including humans. In this paper, we review some of these contributions, trace the path from the origin of molecular genetics to the sequence of the chicken genome, and discuss the merits of the chicken as a model organism for furthering our understanding of biology.

Animals↗
PubMed2002

H3N2 influenza viruses from domestic chickens in Italy: an increasing role for chickens in the ecology of influenza?

In Italy, multiple H3N2 influenza viruses were isolated from chickens with mild respiratory disease and were shown to replicate in the respiratory tracts of experimentally infected chickens; this finding is the first to show that H3N2 influenza viruses can replicate and cause disease in chickens. H3N2 influenza viruses in pigs on nearby farms seemed a likely source of the virus; however, antigenic and molecular analyses revealed that the gene segments of the viruses in chickens were mainly of Eurasian avian origin and were distinguishable from those isolated from pigs and wild aquatic birds in Italy. Thus, several different H3 influenza viruses were circulating in Italy, but we failed to identify the source of the chicken H3N2 influenza viruses that have disappeared subsequently from Italian poultry. Until recently, the transmission of influenza viruses (other than the H5 and H7 subtypes) from their reservoir in aquatic birds to chickens was rarely detected and highly pathogenic and non-pathogenic viruses were considered to be restricted to poultry species. However, the recent reports of the transmission of H9N2 and H5N1 influenza viruses to chickens in Hong Kong and, subsequently, to humans and our findings of the transmission of H3N2 influenza viruses to domestic chickens in Italy suggest an increased role for chickens as an intermediate host in the ecology of influenza.

Animals↗
PubMed1991

Heterophil function in healthy chickens and in chickens with experimentally induced staphylococcal tenosynovitis.

Heterophil function was evaluated in 16 healthy chickens and in 46 chickens with experimentally induced staphylococcal tenosynovitis. In paired blood samples, heterophils from chickens with tenosynovitis had a significant increase in adherence, chemotaxis, phagocytosis, and bacterial killing of Staphylococcus aureus compared to heterophils from healthy chickens. The percent adherence of heterophils to nylon fiber columns increased significantly from a 78.4% mean +/- 6.6% standard deviation to 87.6% +/- 3.2% after induction of staphylococcal tenosynovitis. Heterophil movement following in vitro exposure to saline or endotoxin was increased in chickens with tenosynovitis; 3 +/- 1 heterophils/0.25 mm2 to 10 +/- 6 heterophils/0.25 mm2 and 136 +/- 29 heterophils/0.25 mm2 to 340 +/- 74 heterophils/0.25 mm2, respectively. Endotoxin-activated serum was chemoattractive for heterophils from all chickens. Flow cytometry was used to define the heterophil population on light scatter histograms, evaluate individual cell phagocytosis of latex beads, and quantitate the number of beads phagocytosed per heterophil. When incubated with increased numbers of beads, only heterophils from chickens with tenosynovitis phagocytosed higher numbers of beads. At heterophil to bead ratios of 1:10, the percentage of heterophils that phagocytosed beads increased from baseline values of 37.8% +/- 9.0% to post-infection values of 67.3% +/- 7.5%. Using 1:20 heterophil to bead ratios, heterophil phagocytosis increased from 38.7% +/- 9.9% to post-infection values of 79.8% +/- 7.3%. Heterophils from all chickens were able to phagocytose and kill log phase staphylococcal bacteria. After phagocytosis, the heterophils from chickens with staphylococcal tenosynovitis rapidly decreased the number of viable bacterial colony forming-units per milliliter by approximately one log.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2003

Differences between influenza virus receptors on target cells of duck and chicken and receptor specificity of the 1997 H5N1 chicken and human influenza viruses from Hong Kong.

To study whether influenza virus receptors in chickens differ from those in other species, we compared the binding of lectins and influenza viruses with known receptor specificity to cell membranes and gangliosides from epithelial tissues of ducks, chickens, and African green monkeys. We found that chicken cells contained Neu5Ac alpha(2-6)Gal-terminated receptors recognized by Sambucus nigra lectin and by human viruses. This finding explains how some recent H9N2 viruses replicate in chickens despite their human virus-like receptor specificity. Duck virus bound to gangliosides with short sugar chains that were abundant in duck intestine. Human and chicken viruses did not bind to these gangliosides and bound more strongly than duck virus to gangliosides with long sugar chains that were found in chicken intestinal and monkey lung tissues. Chicken and duck viruses also differed by their ability to recognize the structure of the third sugar moiety in Sia2-3Gal-terminated receptors. Chicken viruses preferentially bound to Neu5Ac alpha(2-3)Gal beta(1-4)GlcNAc-containing synthetic sialylglycopolymer, whereas duck viruses displayed a higher affinity for Neu5Ac alpha(2-3)Gal beta(1-3)GalNAc-containing polymer. Our data indicate that sialyloligosaccharide receptors in different avian species are not identical and provide a potential explanation for the differences between the hemagglutinin and neuraminidase proteins of duck and chicken viruses.

Animals↗
PubMed2005

Regulator of complement activation (RCA) locus in chicken: identification of chicken RCA gene cluster and functional RCA proteins.

A 150-kb DNA fragment, which contains the gene of the chicken complement regulatory protein CREM (formerly named Cremp), was isolated from a microchromosome by screening bacterial artificial chromosome library. Within 100 kb of the cloned region, three complete genes encoding short consensus repeats (SCRs, motifs with tandemly arranged 60 aa) were identified by exon-trap method and 3'- or 5'-RACE. A chicken orthologue of the human gene 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2, which exists in close proximity to the regulator of complement activation genes in humans and mice, was located near this chicken SCR gene cluster. Moreover, additional genes encoding SCR proteins appeared to be present in this region. Three distinct transcripts were detected in RNA samples from a variety of chicken organs and cell lines. Two novel genes named complement regulatory secretory protein of chicken (CRES) and complement regulatory GPI-anchored protein of chicken (CREG) besides CREM were identified by cloning corresponding cDNA. Based on the predicted primary structures and properties of the expressed molecules, CRES is a secretory protein, whereas CREG is a GPI-anchored membrane protein. CREG and CREM were protected host cells from chicken complement-mediated cytolysis. Likewise, a membrane-bound form of CRES, which was artificially generated, also protected host cells from chicken complement. Taken together, the chicken possesses an regulator of complement activation locus similar to those of the mammals, and the gene products function as complement regulators.

Amino Acid Sequence↗