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PubMed1998

Flux Synthesis of LiAuS and NaAuS: "Chicken-Wire-Like" Layer Formation by Interweaving of (AuS)(n)(n)(-) Threads. Comparison with alpha-HgS and AAuS (A = K, Rb).

From the reaction of Au with alkali metal polysulfide liquids, LiAuS and NaAuS were discovered. Orange crystals of LiAuS crystallize in the monoclinic space group C2/c, (no. 15), with a = 8.994(2) Å, b = 8.956(2) Å, c = 7.201(3) Å, beta = 128.68(1) degrees, and Z = 8. Light-yellow planks of NaAuS crystallize in the orthorhombic space group Ccca, (no. 68), with a = 14.658(5) Å, b = 21.043(7) Å, c = 7.118(4) Å, and Z = 32. Both compounds contain infinite one-dimensional (AuS)(n)()(n)()(-) chains, featuring alternating sulfide anions and linear coordinated Au centers. In LiAuS, the chains are zigzag and fully extended and they pack in two mutually perpendicular sets. In NaAuS, the same chains coil in an unusual fashion so that they become interwoven to form layers reminiscent of "chicken-wire". This novel coiling mode allows Au-Au contacts to form, which help to stabilize the structure. The structural relationships between LiAuS, NaAuS, Na(7)Au(5)S(6), AAuQ (A = K, Rb, Cs; Q = S, Se), and alpha-HgS are explored.

Journal Article↗

PubMed1997

[Comparison of plasma thyroxin and insulin concentrations between 10-day old layer and broiler chickens].

In this study both sexes of 10 day old layer and broiler chickens were used to investigate plasma circulating concentrations of 3,3'-5-triiodothyronine (T3), thyroxine (T4) and insulin by using the radioimmunoassay (RIA) methods. The results were as follows: serum T3 concentration was higher in broilers than that in layers (P < 0.01), especially a significant difference between male strains was seen in this experiment (P < 0.001), and the levels of plasma insulin was significantly higher in male broilers than that in male layers (P < 0.001), however, no clear differences in plasma T4 was seen between strains and sexes (P > 0.05). In addition, there were sex differences in T3 and insulin levels in layers, that is to say, those in the female layers was higher than those in the male layers, but no clear deifference was seen between sexes in broilers. A significant positive correlation between T3, insulin and their weight gained (P < 0.05). The results suggest that the levels of serum T3 and Insulin may influence the various growth rate during early posthatch development in layers and broilers.

Animals↗

PubMed1996

Plasma viscosity values and the relationship with age and sex in normal commercial broiler and layer strains of chickens.

1. The plasma viscosity values of normal commercial broiler and layer strains of chicken were measured in relation to age and sex. 2. In both broilers and layers plasma viscosity values decreased at 2 weeks of age; probably reflecting the period of change from maternal plasma protein to the bird's self-synthesised proteins. 3. There was a progressive rise in plasma viscosity in both strains and sexes with age. The increase was greatest in female layers at 17 weeks of age before lay. 4. There was no overall significant difference in viscosity values between fresh and frozen-stored plasma samples.

Aging↗

PubMed1992

Salmonella enteritidis in commercial layer farms in New York state; environmental survey results and significance of available monitoring tests.

Seven hundred fifty-one environmental samples were collected from 76 chicken layer houses in a voluntary Salmonella enteritidis (SE) survey study carried out in New York state between January 15 and April 8, 1991. SE was recovered from both houses on 1 farm. Sampling of manure pits and mice in hen houses was useful for SE screening. Phage types of SE from the environment, birds, and mice were identical. The rapid whole-blood test was unreliable, and culture of cloacal swabs was inadequate for detection of SE carriers. Culture of organs from chickens did not correlate well with results of environmental samples.

Animals↗

PubMed2000

The immunogenicity and pathogenicity of Pasteurella multocida isolated from poultry in Indonesia.

Of 13 field isolates of Pasteurella from chickens and ducks in Indonesia, 10 were confirmed as P. multocida subspecies multocida, one as P. multocida subspecies gallicida and one as P. multocida subspecies septica. Nine were capsular Type A four were Serotype 1, one was Serotype 4, one was Serotype 11, one was Serotypes 4,12, and the remaining six were untypable. Five isolates were pathogenic for mice and two were pathogenic for chickens. Both a trivalent vaccine which included local field isolates and an imported commercial vaccine, were efficacious in layer chickens against challenge with virulent reference and local field strains. Though not statistically significant, the protection provided by the trivalent vaccine against virulent field isolate challenge was slightly better and could provide an improvement over the currently used imported vaccine although further field trials are required. A bacterin vaccine produced from a Serotype 1 field isolate grown in the allantoic sac of embryonated chicken eggs provided chickens with good cross protection against heterologous serotype challenge.

Animals↗

PubMed2005

Experimental assessment of the pathogenicity of H5N1 influenza A viruses isolated in Japan.

We examined the pathogenicity for chickens of two H5N1 avian influenza viruses isolated in Japan, A/chicken/ Yamaguchi/7/2004 (Ck/Yamaguchi/7/04) isolated from outbreaks in commercial layer chickens, and A/duck/Yokohama/aq10/ 2003 (Dk/Yokohama/aq10/03) isolated from duck meat imported from China. All chickens inoculated intranasally with either strain died, and the viruses were reisolated from all organs examined. However, both the mean time of onset of clinical signs and the mean death time of Ck/Yamaguchi/7/04 were shorter than those of Dk/Yokohama/aq10/03.

Administration, Intranasal↗

PubMed2025

Detection of the mgtC gene in multidrug-resistant Salmonella sp. based on isolation of chicken eggshell swabs from traditional Surabaya markets.

BACKGROUND: The virulence of Salmonella sp. is increased by the presence of the mgtC gene, which allows the bacteria to survive in environments with low magnesium levels, such as inside macrophages. Salmonella sp. found on eggshells when they show resistance to three or more classes of antibiotics can be classified as multidrug-resistant (MDR) bacteria. AIM: This study aimed to identify the presence of Salmonella sp. MDR and the mgtC gene in chicken eggshell swabs from traditional markets in Surabaya. METHODS: Swab samples were collected from 160 eggs (80 from layer chickens and 80 from free-range chickens) at 10 traditional markets in Surabaya, Indonesia. Isolation and identification were performed using culture media, including Salmonella Shigella Agar, Gram staining, Triple Sugar Iron Agar, Sulfide Indole Motility, Simmons Citrate Agar, Methyl Red and Voges Proskauer, and Urea Agar. Antibiotic sensitivity testing was performed using the disc diffusion method on Mueller-Hinton Agar. Molecular detection of the mgtC gene was performed using polymerase chain reaction. RESULTS: The results showed that 16.87% (27/160) of the samples were detected positive for Salmonella sp. All Salmonella sp. isolates (27) were resistant to Erythromycin (100%). Resistance was also found to Ampicillin (77.77%, 21/27), Tetracycline (29.62%, 8/27), and Ciprofloxacin (18.51%, 5/27). No resistance to chloramphenicol was observed. In addition, eight of the 27 isolates (29.62%) were classified as Salmonella sp. MDR. The Salmonella sp. MDR isolates also carried the mgtC gene at 87.5% (7/8). CONCLUSION: These findings demonstrate the potential global public health threat posed by MDR Salmonella sp. with the mgtC gene, emphasizing the importance of monitoring and controlling antibiotic resistance in humans and animals.

Animals↗

PubMedDate not supplied

Infectious coryza in meat chickens in the San Joaquin Valley of California.

Two cases of infectious coryza in meat chickens are reported. The first case involved 6-week-old broiler chickens in which only Haemophilus paragallinarum was isolated. The second case involved 11-week-old roaster chickens in which H. paragallinarum and Mycoplasma synoviae were isolated. Both farms were in close proximity to layer-chicken farms where infectious coryza had been previously diagnosed. In both cases, only certain houses on the farm were affected, and mortality in these houses increased slightly. At processing, the condemnation rates for affected houses were considerably higher than rates for unaffected houses. Condemnations for affected houses were mostly due to airsacculitis. A dissecting fibronopurulent cellulitis was a prominent lesion in the second case. This lesion could lead to confusion with chronic fowl cholera and swollen-head syndrome.

Air Sacs↗

PubMed2005

Polymorphisms of 5' flanking region of chicken prolactin gene.

The polymorphisms of 5' flanking region of chicken prolactin (cPRL) gene were examined in several populations of Chinese native Yuehuang, Taihe Silkie and imported White Leghorn Layer chickens. The 5' flanking regions (2638 bp) from Yuehuang, Taihe Silkie and White Leghorn chickens were subjected to sequencing analysis. Four single nucleotide polymorphisms (SNPs) were identified at position -2425(C/T), -2215(T/C), -2063(G/A) and -1967(A/G). A 24-bp indel (insertion or deletion) and a polyA length polymorphism were also identified. For the 24-bp indel locus, three genotypes (AA, AB and BB) were found in Yuehuang chickens, while only two genotypes were detected in Taihe Silkie (AB and BB) and Leghorn chickens (AA and BB). The genotype frequencies of AA, AB and BB were significantly different among the three breeds. For the polyA locus, although three genotypes (CC, CD and DD) were found, only one genotype (CC) was detected in White Leghorn chickens, while two or three genotypes were observed in Chinese native chickens. We used real-time quantitative PCR and radioimmunology assay to investigate the potential association of the 24-bp indel locus with cPRL mRNA expression, plasma cPRL and brooding behaviors, and observed that chickens with genotype AB, which are of the highest incidence of broodiness, had the highest cPRL mRNA levels, providing the possibility that this polymorphic site might be related to the broodiness in chickens via modulating the transcriptional level of cPRL gene. The dissociation among cPRL gene transcription, mRNA storage and hormone release was also observed.

5' Flanking Region↗

PubMed2002

Anticoccidial vaccines for broiler chickens: pathways to success.

The use of live vaccines, either attenuated or non-attenuated, for the control of coccidiosis due to Eimeria infections in broiler breeder or layer chickens is well established. Use in broilers, however, has been slow to gain acceptance. This has been partly for economic reasons, but also because of perceived adverse effects on early chick growth, particularly with non-attenuated vaccines, and concerns about timely onset of protective immunity in such short-lived birds. This review describes advances in understanding of epidemiological factors and recent improvements of administration methods that have helped to allay these fears and to make the use of anticoccidial vaccines in broilers technically achievable. Topics discussed include: (1) types of commercially available vaccine, (2) vaccines in development, (3) vaccination methods and equipment, (4) basis of vaccine efficacy and immunogenic variation of parasites, (5) key factors in the survival, sporulation and dissemination of vaccinal oocysts, (6) descriptions and significance of patterns of litter oocyst accumulation and occurrence of intestinal lesions in vaccinated flocks, (7) rotation of anticoccidial vaccination and chemotherapy to restore drug sensitivity to resistant wild-type coccidia, (8) combinations of anticoccidial vaccination and chemotherapy, (9) interactions between coccidiosis and clostridiosis in broilers and compatibilities of potential control methods, (10) published performance data for live anticoccidial vaccines in broilers, (11) possible further developments of live vaccines.

Animals↗

PubMed1997

Functional characterization of neural and smooth muscle motilin receptors in the chicken proventriculus and ileum.

To characterize the motilin receptors present in the chicken, the effects of chicken motilin (Phe-Val-Pro-Phe-Phe-Thr-Gln-Ser-Asp-Ile-Gln-Lys-Met-Gln-Glu-Lys-Glu-Arg -Asn-Lys-Gly-Gln), Leu13 porcine motilin, canine motilin and three erythromycin derivatives (EMA, EM523, GM611) on the contractility of the chicken gastrointestinal (GI) smooth muscles were investigated in vitro and compared with those in the rabbit duodenum. In the proventriculus longitudinal and circular muscle layers, chicken motilin (3 nM-1 microM) caused an atropine- and a tetrodotoxin-sensitive contraction (EC50 = 39-49 nM), and potentiated the EFS-induced contraction without affecting the responsiveness of acetylcholine. EM523 and GM611 (3-100 microM) contracted the proventriculus longitudinal muscle, and the maximum amplitudes of contraction were about 60% of that induced by chicken motilin. Chicken motilin (0.1 nM-100 nM) also caused contraction of the ileum (EC50 = 7 nM) through direct action on the smooth muscle cells. On the other hand, erythromycin derivatives showed only a weak contractile efficacy (about 20% of the maximum response of chicken motilin) even at high concentrations (10-100 microM). The rank order of potency in the ileum was chicken motilin > canine motilin > or = Leu13 porcine motilin > > GM611 > or = EM523 > or = EMA. GM109 slightly inhibited the ideal contractions induced by Leu13 porcine motilin at 100 microM (pA2 = 3.86). In the rabbit duodenum, chicken motilin was a full agonist with the same intrinsic activity as Leu13 porcine motilin, canine motilin and the erythromycin derivatives. However, the rank order of potency (Leu13 porcine motilin > or = canine motilin > chicken motilin > GM611 > or = EM523 > EMA) was different from that in the chicken ileum. In conclusion, chicken motilin causes an excitatory response in the chicken GI tract through activation of neural (proventriculus) and smooth muscle motilin receptors (ileum). The motilin receptor present in the ileum is different from that demonstrated in the rabbit intestine, because of a different rank order of motilin peptides in producing the contraction, low contracting activity of erythromycin derivatives and low antagonistic efficacy of GM109. Different pharmacological characteristics of the mechanical response induced by motilin peptides and erythromycin derivatives between the proventriculus and the ileum are discussed.

Animals↗

PubMed2004

Intestinal villus recovery in chickens refed semi-purified protein-, fat-, or fibre-free pellet diets.

1. To determine which macronutrient, protein, fat, or fibre is most effective at inducing structural recovery of intestinal villi after feed withdrawal, male layer chickens were allotted to the following groups: intact control (IC), 3-d feed withdrawal (F), ad libitum refeeding of a formula mash diet (AFM), or force-feeding of a formula (FFP) or semi-purified well-balanced (FSP), protein-free (FSPP), fat-free (FSPF), or fibre-free (FSPFi) pellet diets for one day after 3-d feed withdrawal. 2. After refeeding, the formula diet groups increased in villus height and apparent area. However, not all of the semi-purified groups recovered to the levels of the formula diet groups in all light microscopic variables, except in terms of a further decrease in cell mitosis in the FSPP group compared to the F group. Of the semi-purified groups, the FSPFi group tended to be the highest for all variables. This result suggests that the semi-purified diets did not induce villus recovery faster than the formula diet, especially in the case of the protein-free pellet diet. 3. After refeeding, a smooth surface of villus tip in the F group changed to a rough surface, with cell protuberances in the AFM group. This morphological recovery was clearer in the FFP group. Compared with the FFP group, the semi-purified groups had cell protuberances which extended further into the intestinal lumen, and more cell clusters. Among the semi-purified groups, epithelial cells were smaller in the FSPP and larger in the FSPFi than in the other groups. This result suggests that the semi-purified diet can induce a quicker cell recovery than the formula diet but that the protein-free diet is the slowest. 4. The present study demonstrates that protein is the most important nutrient for the recovery of intestinal villi after feed withdrawal.

Animal Feed↗

PubMed1995

Control of Salmonella enteritidis in Sweden.

The Swedish control of Salmonella, with special reference to Salmonella enteritidis, in poultry is described. The control is directed at all serotypes of Salmonella and imported grandparent chickens are controlled, which is considered to be the main reason why Sweden so far is not found to be involved in the worldwide spread of different phagetypes of S. enteritidis. However, this spread has initiated a more stringent control of Salmonella in layers as earlier existed in broilers. Since 1990, 90% of the layer flocks are voluntarily tested for Salmonella before slaughter by bacteriological examination of pooled faecal samples. If S. enteritidis is isolated the flock is destroyed. This test, and in addition two similar tests during the production are mandatory as of January 1st, 1994. The voluntary Salmonella control programme has also been extended to all of the layer parents and hatcheries since 1991. Only heat-treated feed is given to all layer chickens during the rearing period and its use is becoming gradually more common also during the production period. Since 1987, four layer flocks have been found to be infected by S. enteritidis phagetype 4 and one flock with phagetype 6. During 1970-1984, 90% of all flocks of broilers were voluntarily tested bacteriologically for Salmonella before slaughter, and since 1984 such a control is mandatory to all flocks. As a result of this and other controls, S. enteritidis has not been isolated from broilers since 1972. Based on a governmental regulation from 1961, introduced as a result of a large Salmonella epidemic in 1953, Sweden runs an active, official control of Salmonella (Wierup et al., 1992).(ABSTRACT TRUNCATED AT 250 WORDS)

Abattoirs↗

PubMedDate not supplied

Comparison of a modified Edward-type medium and a modified SP4-type medium for primary isolation of Mycoplasma gallisepticum (MG) from chickens vaccinated with the F strain of MG.

The efficacy of two media, an Edward-type medium (EPJ) and a modified SP4-type medium (SP4-PS), were compared for primary isolation of Mycoplasma gallisepticum (MG) from commercial layer chickens (n = 58) vaccinated with the live F strain of MG. Three groups of chickens that differed in the interval after vaccinal exposure to the F strain (32, 41, and 102 weeks) were studied at necropsy. Mycoplasma isolation was attempted from the trachea, sinus, and cloaca using lavage and swab techniques but was successful only from the trachea and sinus. MG was isolated from 39 (8.4%) of 463 culture attempts from 58 tracheal inocula and 58 sinus inocula. Isolation of MG was successful more frequently using EPJ medium than SP4-PS medium, and isolation occurred more often from the sinus than from the trachea. Of the 58 chickens studied, 19 (33%) were shown by culture to be infected with MG. Isolation was successful only from 32- and 41-week post-vaccination exposure groups. However, all chickens studied were serologically positive for MG antibody by rapid-plate agglutination and hemagglutination-inhibition assays.

Agglutination Tests↗

PubMed1996

A serological survey of turkey rhinotracheitis virus infection in chickens in Japan.

A total of 4,111 chicken sera collected from 1985 to 1995 at 137 farms in 36 prefectures were subjected to an enzyme-linked immunosorbent assay (ELISA) to test for antibodies against turkey rhinotracheitis (TRT) virus. The antibodies to TRT virus were detected in the chicken sera collected from 1988 to 1995, but the antibodies to TRT virus were undetectable in the sera of chickens collected before 1987. The antibody positive rates each year ranged from 2.2% (1988) to 54.2% (1995). Recently, the TRT virus has spread over the flocks of commercial broiler and layer chicken throughout the country. The serological findings indicated that the TRT virus had invaded the chickens before 1988, and has been widespread thereafter in Japan.

Animals↗

PubMed1982

Cell differentiation, protein synthesis rate and protein accumulation in muscle cell cultures isolated from embryos of layer and broiler chickens.

Muscle cell cultures were prepared from the leg muscle of 12-d layer and broiler chicken embryos. Cultures were then compared over a 10-d period from their capacity to differentiate into multinucleated myotubes and to synthesize and accumulate protein. Differentiation was qualitatively similar in the two cell types as evidenced by myoblast fusion that occurred rapidly during the first 2 d and remained essentially constant between d 3 and 10. However, several quantitative differences were observed. Even though the number of myotubes per culture was comparable between layers and broilers throughout development, layer muscle cultures usually exhibited a higher percentage fusion and more myonuclei per culture than broiler muscle cultures. Additionally, the nuclear density (i.e., the number of nuclei per myotube segment) was approximately 25% greater in layer cultures than in broilers between d 2 and 10 in culture. The rate of incorporation of 3H-leucine into total protein during pulse labeling experiments was comparable in muscle cultures of layers and broilers; however, broiler muscle cells accumulated approximately 40% more total protein per nucleus between d 6 and 10. Myosin heavy chain synthesis rate was higher in layer than in broiler muscle cultures, but broiler muscle cultures accumulated approximately 30% more myosin heavy chain than layers between d 6 and 10. The half-life of myosin heavy chain was 45 h in layer muscle cultures and 103 h in broiler muscle cultures. Thus, the capacity of broiler cells to accumulate more muscle protein was primarily due to a drastically slower protein breakdown rate.

Animals↗

PubMed2004

Assessing the roles of endogenous retrovirus EAV-HP in avian leukosis virus subgroup J emergence and tolerance.

Avian leukosis virus (ALV) subgroup J is thought to have emerged through a recombination event between an unknown exogenous ALV and the endogenous retrovirus elements designated EAV-HP. All EAV-HP elements identified to date in the chicken genome show large deletions, including that of the entire pol gene. Here we report the identification of four segregating chicken EAV-HP proviruses with complete pol genes, one of which shows exceptionally high sequence identity and a close phylogenetic relationship with ALV-J with respect to the env gene. Embryonic expression of EAV-HP env has been suggested as a factor associated with immunological tolerance induction in a proportion of ALV-J-infected meat-type chickens. In support of this, env gene transcripts expressed from two of the four newly identified EAV-HP proviruses were demonstrated in chicken embryos. However, when ALV-J-infected outbred meat-type chickens were assessed, the presence of intact EAV-HP proviruses failed to directly correlate with ALV-J tolerance. This association was further examined using F(2) progeny of two inbred lines of layer chicken that differed in EAV-HP status and immunological responses to ALV-J. Immunological tolerance developed in a small proportion of F(2) progeny birds, reflecting the expected phenotypic ratio for inheritance of a double-recessive genotype; however, the status of tolerance did not show any direct correlation with the presence of the intact EAV-HP sequence. Nevertheless, identification of an intact chicken EAV-HP locus showing a uniquely close relationship to the ALV-J prototype clone HPRS-103 in the env region provides the strongest evidence of its contribution to the emergence of ALV-J by recombination.

Animals↗

PubMed2006

Early steps in neural development.

We studied early neurulation events in vitro by transplanting quail Hensen's node, central prenodal regions (before the nodus as such develops), or upper layer parts of it on the not yet definitively committed upper layer of chicken anti-sickle regions (of unincubated blastoderms), eventually associated with central blastoderm fragments. We could demonstrate by this quail-chicken chimera technique that after the appearance of a pronounced thickening of the chicken upper layer by the early inductive effect of neighboring endophyll, a floor plate forms by insertion of Hensen's node-derived quail cells into the median part of the groove. This favors, at an early stage, the floor plate "allocation" model that postulates a common origin for notochord and median floor plate cells from the vertebrate's secondary major organizer (Hensen's node in this case). A comparison is made with results obtained after transplantation of similar Hensen's nodes in isolated chicken endophyll walls or with previously obtained results after the use of the grafting procedure in the endophyll walls of whole chicken blastoderms.

Animals↗