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At least 19 recordsLinked to original sources
PubMed2024

Intestinal microbiome profiles in broiler chickens raised without antibiotics exhibit altered microbiome dynamics relative to conventionally raised chickens.

The present study was undertaken to profile and compare the cecal microbial communities in conventionally (CONV) grown and raised without antibiotics (RWA) broiler chickens. Three hundred chickens were collected from five CONV and five RWA chicken farms on days 10, 24, and 35 of age. Microbial genomic DNA was extracted from cecal contents, and the V4-V5 hypervariable regions of the 16S rRNA gene were amplified and sequenced. Analysis of 16S rRNA sequence data indicated significant differences in the cecal microbial diversity and composition between CONV and RWA chickens on days 10, 24, and 35 days of age. On days 10 and 24, CONV chickens had higher richness and diversity of the cecal microbiome relative to RWA chickens. However, on day 35, this pattern reversed such that RWA chickens had higher richness and diversity of the cecal microbiome than the CONV groups. On days 10 and 24, the microbiomes of both CONV and RWA chickens were dominated by members of the phylum Firmicutes. On day 35, while Firmicutes remained dominant in the RWA chickens, the microbiome of CONV chickens exhibited am abundance of Bacteroidetes. The cecal microbiome of CONV chickens was enriched with the genus Faecalibacterium, Pseudoflavonifractor, unclassified Clostridium_IV, Bacteroides, Alistipes, and Butyricimonas, whereas the cecal microbiome of RWA chickens was enriched with genus Anaerofilum, Butyricicoccu, Clostridium_XlVb and unclassified Lachnospiraceae. Overall, the cecal microbiome richness, diversity, and composition were greatly influenced by the management program applied in these farms. These findings provide a foundation for further research on tailoring feed formulation or developing a consortium to modify the gut microbiome composition of RWA chickens.

Animals↗
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↗
PubMed1977

Chicken secretory immunoglobulin: chemical and immunological characterization of chicken IgA.

1. Chicken IgA purified from biliary fluids was chemically and immunologically characterized. 2. Chicken IgA was determined to be the only immunoglobulin class present in bile. Gel filtration studies reveal polymeric IgA e.g. 17-19S. 3. Antigenically, chicken IgA is distinct from chicken IgG, and IgM. 4. Chicken IgA does not show antigenic homology to human IgA. 5. SDS poly-acrylamide gel electrophoresis revealed IgA to possess heavy chains of 60,000 and light chains of 24,000 mol. wt, respectively. 6. Peptide mapping of tryptic digests of chicken alpha chains reveals approximately 35 peptides. The peptide map pattern is distinct from chicken gamma chains.

Animals↗
PubMed1978

Isolation and cultivation of bovine ephemeral fever virus in chickens and chicken embryos.

Unadapted bovine ephemeral fever (BEF) virus was isolated from cattle blood after intravenous inoculation into chicken embryos. Infected embryos died or hatched as abnormal chickens. The chick embryo was slightly less sensitive to unadapted BEF virus than were Vero cell cultures, but the use of embryos avoids the several blind passages that are required to isolate BEF virus in unweaned mice. Chick embryos were considerably less efficient than Vero cell culture or unweaned mice in detecting Vero cell-adapted and mouse-adapted BEF virus respectively. Viraemia was demonstrated in chicken embryos at 1-4 days and in one-day-old chickens at 1-3 days after intravenous inoculation of BEF virus. BEF virus was demonstrated by isolation and by immunofluoresence in heart, brain, lung and liver of chicken embryos at 1-5 days and in lung and liver of one-day-old chickens at 1-2 days, after intravenous inoculation. The isolated viruses were confirmed as BEF virus by neutralization with immune mouse ascitic fluid. BEF neutralizing antibodies were produced in 4-week-old and adult chickens after intravenous inoculation with BEF virus.

Animals↗
PubMed2025

GCRP: Integrated Global Chicken Reference Panel from 11,951 Chicken Genomes.

Chickens are a crucial source of protein for humans and a popular model animal for bird research. Despite the emergence of imputation as a reliable genotyping strategy for large populations, the lack of a high-quality chicken reference panel has hindered progress in chicken genome research. To address this, here we introduce the first phase of the 100K Global Chicken Reference Panel (100K GCRP). Currently, two panels are available: a comprehensive mix panel (CMP) for domestication diversity research and a commercial breed panel (CBP) for breeding broilers specifically. Evaluation of genotype imputation quality showed that CMP had the highest imputation accuracy compared to imputation using existing chicken panels in Animal-SNPAtlas and Animal Genotype Imputation Database (AGIDB), whereas CBP performed stably in the imputation of commercial populations. Additionally, we found that genome-wide association studies using GCRP-imputed data, whether on simulated or real phenotypes, exhibited greater statistical power. In conclusion, our study indicates that the GCRP effectively fills the gap in high-quality reference panels for chickens, providing an effective imputation platform for future genetic and breeding research. The project includes 11,951 samples and provides services for various applications on its website at http://farmrefpanel.com/GCRP/#/.

Animals↗
PubMed1977

EA-rosette-forming cells in chickens: presence in spleens of bursectomized chickens and relationships to B-lymphocytes.

Spleen cells from 3-month-old chickens which had been surgically and chemically bursectomized were examined for rosette-forming lymphocytes (RFL). Finding no correlation between the degree of agammaglobulinemia in bursectomized chickens and the percentage of RFL in their spleens demonstrated a dissociation between two B-cell dependent functions, namely, immunoglobulin production and rosette-forming ability. In fact, the percentage of RFL in the spleens of agammaglobulinemic chickens was found to be slightly higher than those of normal chickens. The data indicate that RFL in spleens of normal chickens are B cells, and suggest the existence of a population of rosette-forming B lymphocytes in agammaglobulinemic bursectomized chickens.

Agammaglobulinemia↗
PubMed1978

Structural and genetic studies on chicken 7S immunoglobulin allotypes. IV. The presence of an unexpected chicken immunoglobulin heavy chain allotype: subclass or pseudoallele?

Low concentrations of allotypic specificity CS-1.1 were detected in the sera of two inbred chicken lines [University of California, Davis (UCD) 7 and Regional Poultry Research Laboratory 15I4] previously reported to lack this specificity. The CS-1.1 alloantigen in 15I4 chickens has the same specificity as the major allotype in a line of chickens (UCD 2) in which it was initially defined. In 15I4 chickens, CS-1.1 allotype is present on a population of molecules distinct from those which carry the major allotype; thus a second 7S Ig H chain locus, CS-2, is proposed. The concentration of CS-1.1-bearing molecules determined by two different methods was 7 microgram/ml and 230 microgram/ml in 15I4, whereas UCD 2 chickens had 4 mg/ml of CS-1.1 molecules. The levels of CS-1.1 inhibitory activity in 15I4 birds remained relatively constant over a 30-day period. The presence of two 7S Ig populations in 15I4 chickens may be interpreted as evidence either for 7S Ig subclasses with shared allotypes or for a pseudoallelic organization of genes controlling expression of 7S Ig H chains. The results were consistent with the presence of redundant C region genes, differing in allotypes, whose expression is under the control of an as yet undefined regulatory mechanism.

Alleles↗
PubMed1976

A comparison of the structure of chicken erythrocyte and chicken liver chromatin.

The structure of chicken erythrocyte and chicken liver chromatin has been studied by enzymatic digestion with micrococcal nuclease and DNAase I. Comparison of the fragments produced by brief digestion with micrococcal nuclease indicates that chicken erythrocyte chromatin has a longer nucleosome repeat than chicken liver chromatin, 212 base pairs as opposed to 200 base pairs (bp). More extensive digestion with micrococcal nuclease demonstrates that both tissues have 140 bp mucleosome cores. The difference in the length of the nucleosome repeat must therefore result from a difference in the length of the DNA linker between cores. Chicken erythrocyte chromatin is known to contain a tissue-specific, H1-like histone, H5, and to be genetically dormant. A model is presented to explain how changes in histone H1 could cause changes in the nucleosome repeat length and thereby alter the genetic activity of chromatin.

Animals↗
PubMed1978

Fc receptor-bearing lymphoid cells in the chicken. II. Relative increase of Fc(IgG) receptor bearing cells in obese strain-chickens.

An EA rosette technique is used to study ontological development and organ distribution of Fc(IgG) receptor-bearing lymphoid cells in normal CS White Leghorn chickens, and in OS chickens with spontaneous autoimmune thyroiditis. During the embryonic period, no difference was seen between CS and OS in the tissue distribution of cells with Fc receptors. At the time of hatching and subsequently, the OS chickens possessed relatively more Fc receptor-bearing lymphoid cells than did CS chickens. The increase of Fc receptor-bearing lymphoid cells was most prominent among spleen cells. No difference in the affinity of Fc receptors between lymphocytes of the OS and CS chickens was demonstrated. The possible role of Fc receptor-carrying cells in the development of autoimmune thyroiditis is discussed.

Animals↗
PubMed1975

Horizontal transmission of turkey herpesvirus to chickens. 3. Transmission in three different lines of chickens.

Horizontal transmission of turkey herpesvirus (HVT) was studied in three separate trials using three different lines of chickens in each trial. There was no horizontal spread of HVT to contact cagemates through 8 weeks regardless of the line of donor chickens, when inoculated subcutaneously with 9.2 times 10-3 plaque-forming units (PFU) of HVT at 1 week of age. The virus spread poorly to a few cagemates from an experimental line of White Leghorns (W.S.U.-V.S.), but not from a commercial line of White Leghorns (C.-W.L.) or meat-type (C.-M.T.) chickens, when inoculated with 9.4 times 10-4 PFU of HVT at 1 week of age. The virus spread readily to contact cagemates from W.S.U.-V.S. but not at all from C.-W.L. or C.-M.T. chickens when inoculated with 2 times 10-4 PFU of HVT at 8 weeks of age. The incidence among cagemates of contact infection by HVT appeared similar regardless of genetic lines. This observation indicated a difference among different genetic lines of chickens in the development and/or shedding of infectious HVT following virus inoculation.

Animals↗
PubMed1976

Horizontal transmission of turkey herpesvirus to chickens. 5. Airborne transmission between chickens.

Airborne transmission of turkey herpesvirus (HVT) between chickens was studied in two trials using an experimental line of White Leghorns. HVT either did not spread or spread poorly to chickens that had been exposed for 8 weeks to the exhaust air from a cage containing donor chickens inoculated with HVT at 8 weeks of age. There was no airborne transmission of HVT to chickens that had been exposed for 4 weeks. This study indicated a possible by an infrequent spread of HVT between chickens via airborne route.

Air Microbiology↗
PubMed1977

Effects of lymphocytes from Marek's disease-infected chickens on mitogen responses of syngeneic normal chicken spleen cells.

PHA responses have been measured in lymphoid cell cultures prepared by mixing normal chicken spleen cells with spleen or thymus cells from syngeneic chickens infected with the oncogenic herpesvirus MDV. Results of these studies may be summarized as follows: 1) spleen cells from MDV-infected chickens with visceral lymphomas inhibit the PHA response of normal spleen cells possibly by release of soluble inhibitory factors in response to the mitogen; 2) lymphoid cells from asymptomatic MDV-infected chickens, although hyporeactive themselves to PHA, can have a stimulatory effect on PHA responses of normal spleen cells in mixed cultures; 3) spleen cells from MDV-infected chickens, effectively protected from viral oncogenesis by HVT vaccination, show normal reactivity to PHA in spearate cultures and may react in mixed cultures like normal lymphocytes, with neither a pronounced stimulatory nor inhibitory effect on the PHA response of normal spleen cells.

Animals↗
PubMedDate not supplied

Biological characters and bacteriophage typing of Staphylococcus aureus isolated from chicken staphylococcosis and commercial balanced chicken food in Argentine.

During 1976-78, 33 S. aureus strains were isolated from chickens suffering from dermatitis and septicemia, omphalitis, pneumonia, arthritis and tenosynovitis; and from a commercial balanced chicken food. All the strains were classified into the biotype B of Hájek and Marsálek. Twenty-nine (87.8%) strains could be classified into Sato et al biological type 4 although they differed from it in its ability to grow at 45 degrees C. The remaining 4 strains differed from the others because they failed in producing hemolysis in bovine and ovine blood agar, egg yolk reaction and splitting of Tween 80. Thirty (90.9%) strains were lysed by avian phages: 28 strains at 1 x RTD and 2 at 100 x RTD. Twenty seven (93.1% strains of the Sato et al biotype 4 were sensitive to the phages CH42/CH43/CH63/CH37 of avian group II, and 2 strains to the phage CHA1 at 100 x RTD. Only one of the 4 unclassified strains could be typed by phage CH4 of avian group I at 1 x RTD. Twenty seven (81,8%) strains were typable at 100 x RTD by the basic set of human phages: 26 strains belonged to group III (53 and 53/77) and 1 to a mixed group I/III (79/53/77). The typable strains belonged only to Sato et al biotype 4. None of 33 strains were sensitive to any of the bovine phages. The biological characters and bacteriophage typing of the S. aureus showed that almost all the strains belong to chicken types. The strains isolated from food belong to the same chicken biotype and phagetype as the strains isolated from dermatitis, septicemia, omphalitis and pneumonia. The strains isolated from arthritis and tenosynovitis were different from the ones isolated from other pathologies.

Animal Feed↗
PubMed1979

Viral protein sythesis by tissues from avian leukosis virus-infected chickens. II. Effect of passive neutralizing antibody in normal and agammaglobulinaemic chickens.

Synthesis in vitro of avian leukosis virus (ALV) group (gs proteins, p27 and p12, by various tissues from chickens infected within a few days after hatching was studied by means of autoradiography of immunoelectrophoretic patterns. Viral protein was synthesized in all tissues of chicks examined between days 18 and 50 of age after which time liver, kidney, bursa, thymus, and spleen became negative. The lung and genital organs of the chicks, however, continued to synthesize viral protein up to 100 days of age, when the experiment was ended. Repeated injections of neutralizing chicken antibody to ALV (Ab) starting on day 26 or 37 caused gs protein to decrease in spleen, liver, and thymus within 5 days but not in bursa, lung, and genital organs. Agammaglobulinaemic (Agamma) chickens showed prolonged persistence of gs protein synthesis in the spleen and liver; this synthesis was abrogated by passive Ab. Liver from Agamma chickens, however, also became negative without Ab treatment. The relative roles of antibody and cellular immunity in influencing ALV replication during the initial phase of infection before lymphoma development are discussed.

Agammaglobulinemia↗
PubMed1979

Isolation of the chicken beta-globin gene and a linked embryonic beta-like globin gene from a chicken DNA recombinant library.

A library of random chicken DNA fragments, 15-22 kb long, has been prepared in the vector lambda Charon 4A. This library was screened with combined adult and embryonic globin cDNA, and several independent globin gene-containing recombinants were isolated. One of these recombinants, lambda Chicken beta-globin 1 (lambda C beta G1), contains the adult chicken beta-globin gene and a closely linked embryonic beta-like globin gene. Both genes are transcribed in the same direction with the adult gene located 5' to the embryonic gene. Electron microscopic visualization of R loop structures generated by hybridization of globin RNA to lambda C beta G1 demonstrates that both globin genes contain major intervening sequences about 800 bp long, similar to those present in mammalian beta-globin genes. The adult beta-globin gene also contains a minor (approximately 100 bp long) intervening sequence analogous to the one observed in mammalian beta-globin genes. Restriction enzyme analysis of the adult beta-globin gene on lambda C beta G1 is consistent with the hypothesis that its two intervening sequences occur in the same positions with respect to the beta-globin amino acid sequence as do the corresponding mammalian intervening sequences.

Animals↗
PubMed1976

Chemical carcinogen-induced transplantable fibrosarcomas in histocompatible chickens. I. Incidence of tumor induction in normal and bursectomized chickens.

Transplantable fibrosarcomas were developed in two B-locus-defined chicken strains from primary tumors induced by im injection of 2 mg 7,12-dimethylbenz[a]anthracene in 0.1 ml dimethyl sulfoxide into 1- to 2-week-old chicks. Viruses were not important factors in transmission of these tumors as evidenced by 1) transplantability only within the chicken strain of origin, 2) lack of evidence for a filterable agent, 3) maintenance of donor karyotypic characteristics upon transplantation, 4) lack of DNA polymerase and avian leukosis virus group-specific protein production in vitro. Bursectomized inbred SC chickens had a higher incidence of tumor induction than did normals of the same strain. Although the exact interpretation of this finding posed some problems, as discussed, an important function of enhancing antibody in tumor growth appeared excluded.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1976

[Experimental reproduction of necrotic enteritis in the chicken. 2. Further mono- and polyinfections with CL. perfringens and coccidia with special reference to ground-kept chickens].

Coccidial oocysts and/or vegetative germs, spores, and toxins of Cl. perfringens Type A were used in mono-infection and poly-infection experiments on SPF chicken aged seven and 56 days and kept under different conditions. Necrotic enteritis was regularly reproduced in all experimental groups with polyinfections. In chicken aged seven days necrotic enteritis was reproduced even after repeated mono-infections with 4 X 10(9) gerus and toxin of Cl. perfringens. The loss figures recorded from ground-kept infected groups were higher than those established from the cage-kept animals. The pathologica-anatomic findings recorded from the dead chicken included necrotic, ulcerative, and catarrhal to haemorrhagic intestinal inflammations, with necrotic enteritis being most strongly pronounced in the ileum and jejunum. All infected groups lost not only animals but weight as well. Their average weight on the 21 st day from the onset of infection was up to 26.4 per cent lower than that of the control groups.

Animals↗