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At least 343 records · Page 19Linked to original sources
PubMed1996

[The epidemiology of helicobacteriosis in humans; studies of the survival capacity of the microbe in food].

In man suffering from diseases of the stomach and the duodenum (gastritis, ulcus, enteritis, neoplasms), Helicobacter pylori (H..pylori) is frequently detected in the mucous membrane of the stomach. Up to now the spread of this agent is not quite clear. Since the direct transmission in humans can be taken for granted, the following study was to find out whether and for how long the agent mentioned above is able to survive in selected food and whether an infection of the consumer by these contaminated food is possible. 376 samples of secretions from the udder of healthy cows and those with mastitis where tested for the presence of H. pylori along with 100 stomachs of chicken from different flocks. In no case H. pylori could be detected. H. pylori was inoculated in high concentrations into milk and some milk-products. From cooled milk samples the agent could still be reisolated after six days in a density up to 10(3) CFU/ml of milk. At room-temperature or 37 degrees C resp. the pathogen could be detected in milk for three to four days only. In yoghurt the agent kept viable for three hours only, whereas in kefir for 24 hours. Mean survival time of then hours was found in pH-neutral curd cheese. The incubation of H.pylori in sterile drip from chicken and in physiologic saline resulted in maximal survival time of at least 48 hours at room temperature. But in H.pylori-broth the number of microorganisms had dropped below the limit of detectability only after 72 hours. At refrigerator-temperature (7 degrees C) H. pylori could still be detected within these three media after 72 hours in high concentrations. In drip from chicken kept at-20 degrees C before thawing H. pylori showed a considerable survival time. After four weeks its number had only dropped by one to two log cycles, whereas in saline and in broth the agent could not be detected anymore after one week at the most. Experiments concerning tenacity showed: On culture-media with different pH-values the growth-optimum of H. pylori was between pH 6.1 and 7.3 H. pylori was suspended in melting water from chicken and brought in thin layers onto wooden board, plastic and ceramic tiles. The bacterium could be recultured from these surfaces only as long as these were moist. At room-temperature the bacterium could not be detected anymore on wood after 30 minutes, on plastic or ceramic tiles after 90 minutes. At refrigerator-temperature the administered suspensions dried more slowly, so that H. pylori survived longer, but it still could not be isolated anymore on wood after 240 minutes, on plastic or ceramic tiles after 300 minutes. The decimal reduction-time for H. pylori suspensions in broth were. 72 sec. at +50 degrees C 43 sec. at +52 degrees C 20 sec. at +55 degrees C 10 sec. at +57 degrees C 4 sec. at +60 degrees C from which data z = 7.9 +/- 0.01 degrees C can be calculated. From these experiments on can conclude, that in all probability fresh milk and chicken do not contain H. pylori and thus do not represent a source of infection for man. After contamination of slaughtered chicken within the abattoir or from milk and milk-products within dairy industry by insufficient hygiene-management of infected personnel it can not be excluded, that H. pylori gets into households by these foods. An infection of the consumer by this route is not very likely, but can not be excluded with complete certainly.

Animals↗
PubMed2001

Eliciting antigen-specific egg-yolk IgY with naked DNA.

Immunization with naked DNA was used to elicit chicken egg yolk antibodies (IgY). Layer hens were inoculated with plasmid DNA encoding the enhanced green fluorescent protein, the fusion protein of Newcastle disease virus, and VP2 of African horse sickness virus. IgY was extracted from egg yolks by polyethylene glycol precipitation. Specific antibodies were present in the yolks of eggs from hens immunized with each of the three different plasmids. This approach to raising polyclonal antibodies obviates the need to produce and purify large quantities of proteins for immunization and can potentially yield large amounts of diagnostically or therapeutically useful reagents.

African Horse Sickness Virus↗
PubMed2001

Quantitative assessment of retinoid signaling pathways in the developing eye and retina of the chicken embryo.

Retinoid signaling has been implicated as an important regulator of retinal development and differentiation. We have used state of the art high-pressure liquid chromatography to identify and quantitate biologically active retinoids, immunohistochemistry to localize the retinoic acid synthetic enzyme retinaldehyde dehydrogenase 2 (RALDH2), and nucleic acid assays to quantitate and localize retinoid receptor gene transcripts in the developing eye and retina of the chicken. Our results demonstrate spatial distinctions in retinoid synthesis and signaling that may be related to laminar differentiation in the developing retina. Retinoic acids (RAs) and their precursor retinols (ROHs) are the predominant retinoids in the developing eye. All-trans-RA and all-trans-3,4-didehydro-RA are present in the neuroepithelium in approximately equal amounts from early stages of neurogenesis until shortly before hatching. The retinoid X receptor (RXR) ligand 9-cis-RA is undetectable at all stages; if present, it cannot exceed a small percentage of the total RA content. RAs are not detected in the pigment epithelium. All-trans-ROH is present in the neuroepithelium and pigment epithelium, whereas all-trans-3,4-didehydro-ROH is detected only in the pigment epithelium and/or the choroid and sclera. RALDH2 immunoreactivity is intense in the choroid, low or absent in the pigment epithelium, and moderate in the neuroepithelium, where it is highest in the outer layers. Transcripts of all five chicken retinoid receptor genes are present in the neural retina and eye throughout development. During the period of neurogenesis, at least three of the receptors (RAR gamma, RXR gamma, RXRalpha), exhibit dynamic patterns of differential localization within the depths of the neural retina.

Aldehyde Oxidoreductases↗
PubMed1994

Growth hormone secretory characteristics of sex-linked dwarf and normal-sized chickens reared on a control or on a 3,3',5-triiodothyronine-supplemented diet.

This study examined the pulsatile presence of growth hormone (GH) in the plasma--which reflects its pulsatile release--of 8-week-old male sex-linked dwarf (dwdw) or normal-sized (Dwdw) chickens from a brown-egg layer strain reared on a control or on a 0.5 ppm triiodothyronine(T3)-supplemented diet. The overall GH mean, amplitude, and baseline levels of control dw chickens were significantly higher than those of control Dw chickens. No differences in peak length or peak frequency between genotypes were observed. Dietary T3 supplementation abolished the pulsatile GH release in both genotypes. T3 treatment depressed the mean GH levels of Dw but not of dw chickens.

Animals↗
PubMedDate not supplied

[Lipids of Raillietina tetragona and Raillietina echinobothrida cestodes from the intestines of hens].

Lipids of the cestodes R. tetragona and R. echinobothrida, parasites of chickens, were studied by thin-layer and gas-liquid chromatography methods. The quantity of neutral lipids amounts to 74.4% in R. tetragona and to 73.1% in R. echinobothrida. Triglycerides amount to 35.6% and 38.4% of the neutral lipids in these species, sterols to 21.6% and 17.2%, sterol esters to 25.1% and 32.0%, diglycerides to 2.8% and 1.4% and free fatty acids to 7.8% and 6.5%, respectively. Fatty acids content of worms is similar but not identical of that of chicken intestine lipids. Cestode infection affects the lipid content of chicken intestine resulting in the decrease of triglycerides and oleic acid quantities and in the increase of the amount of free fatty acids and stearic acid.

Animals↗
PubMedDate not supplied

Isolation and characterization of a novel antigenic subtype of infectious bronchitis virus serotype DE072.

Three infectious bronchitis virus (IBV) isolates, CU82792, CU82805, and CU82808, were recovered from sentinel chickens placed with three different layer flocks of a large commercial poultry farm in New York State. The three isolates were classified as members of the DE072 serotype on the basis of 1) their S1 genes could be amplified with only a modified primer designed for the DE072 serotype and 2) their restriction fragment length polymorphism patterns, after digestion with endonucleases HaeIII, BstyI and XcmI, were indistinguishable from that of DE072 virus. Additional characterization of one of the isolates, CU82805, revealed that its S1 gene bears approximately 96% identity at the nucleotide level and 94% identity at the amino acid level with DE072. Yet, in an in vitro reciprocal virus neutralization test, only a one-way neutralization was observed, i.e., antiserum to CU82805 neutralized DE072, whereas CU82805 was not neutralized by DE072 antiserum. Implications of these findings with regard to IBV diagnosis and immunization are discussed.

Amino Acid Sequence↗
PubMed1984

Mycoplasma gallisepticum isolation in layers.

Mycoplasma gallisepticum (MG) isolations in live chickens have been made from swabs obtained primarily from the trachea or nasal exudates. As tracheal swabs are often contaminated with feed and because tracheal swabbing may be stressful to the bird, this study was conducted to determine if swabs from the choanal cleft (palatine fissure) would yield MG isolation rates comparable to MG isolation rates of swabs taken from the trachea. Commercial Leghorns from 17 to 22 weeks of age were inoculated via eyedrop with the F strain of MG. Swabs were made from the trachea or the choanal cleft region (palatine fissure) when the chickens were 58 to 63 weeks of age; MG was isolated from 15 of 101 tracheal swab samples and from 51 of 108 choanal cleft swab samples. This study indicates that swabs taken from the choanal cleft region yield higher isolation rates and are more easily obtained than tracheal swabs.

Age Factors↗
PubMed1999

Gonadotropin regulation of inhibin alpha-subunit mRNA and immunoreactive protein in cultured chicken granulosa cells.

Gonadotropin regulation of the inhibin alpha-subunit was investigated in chicken granulosa cell cultures. Granulosa layers were isolated from the F(1) and F(3) + F(4) follicles from three to four hens, pooled according to size, dispersed, and cultured (n = 3 replications for each experiment). In Experiments 1 and 2 either ovine LH or FSH was added to the cultures at doses of 0, 5, and 25 ng/ml. The cultures were terminated at 4, 24, and 48 h after plating. For both follicle sizes the expression of mRNA for the inhibin alpha-subunit was less (P < 0.05) at 24 and 48 h in untreated cells than in those treated with both doses of LH. Expression of the mRNA for the inhibin alpha-subunit was significantly increased only by the 25 ng/ml dose of FSH and only in the F(1) follicle at 24 and 48 h compared to the untreated cells. After 48 h of culture, immunoreactive alpha-subunit protein accumulation was greater for both follicle types in the media of cells treated with the highest dose of LH and FSH than in the media from untreated cells. In Experiment 3, doses of 0, 5, 25, or 50 ng/ml of either LH or FSH were added to F(1) and F(3) + F(4) granulosa cells. All cultures were terminated at 48 h. LH and FSH increased the expression of the mRNA and immunoreactive protein for the inhibin alpha-subunit equally in a time-dependent manner. These experiments indicate that gonadotropins enhance the expression of both the mRNA and the protein for the inhibin alpha-subunit in chicken granulosa cells.

Animals↗
PubMed2004

Quantitative trait loci with parent-of-origin effects in chicken.

We investigated potential effects of parent-of-origin specific quantitative trait loci (QTL) in chicken. Two divergent egg-layer lines differing in egg quality were reciprocally crossed to produce 305 F2 hens. Searching the genome using models with uni-parental expression, we identified four genome-wide significant QTL with parent-of-origin effects and three highly suggestive QTL affecting age at first egg, egg weight, number of eggs, body weight, feed intake, and egg white quality. None of these QTL had been detected previously using Mendelian models. Two genome-wide significant and one highly suggestive QTL show exclusive paternal expression while the others show exclusive maternal expression. Each of the parent-of-origin specific QTL explained 3-5 % of the total phenotypic variance, with the effects ranging from 0.18 to 0.4 phenotypic SD in the F2. Using simulations and further detailed analyses, it was shown that departure from fixation in the founder lines, grand-maternal effects (i.e. mitochondrial or W-linked) and Z-linked QTL were unlikely to give rise to any spurious parent-of-origin effects. The present results suggest that QTL with parent-of-origin specific expression are a plausible explanation for some reciprocal effects in poultry and deserve more attention. An intriguing hypothesis is whether these effects could be the result of genomic imprinting, which is often assumed to be unique to eutherian mammals.

Age Factors↗
PubMed2004

A genetic variation map for chicken with 2.8 million single-nucleotide polymorphisms.

We describe a genetic variation map for the chicken genome containing 2.8 million single-nucleotide polymorphisms (SNPs). This map is based on a comparison of the sequences of three domestic chicken breeds (a broiler, a layer and a Chinese silkie) with that of their wild ancestor, red jungle fowl. Subsequent experiments indicate that at least 90% of the variant sites are true SNPs, and at least 70% are common SNPs that segregate in many domestic breeds. Mean nucleotide diversity is about five SNPs per kilobase for almost every possible comparison between red jungle fowl and domestic lines, between two different domestic lines, and within domestic lines--in contrast to the notion that domestic animals are highly inbred relative to their wild ancestors. In fact, most of the SNPs originated before domestication, and there is little evidence of selective sweeps for adaptive alleles on length scales greater than 100 kilobases.

Alleles↗
PubMed2006

Susceptibility of various parental lines of commercial white leghorn layers to infection with a naturally occurring recombinant avian leukosis virus containing subgroup B envelope and subgroup J long terminal repeat.

Chickens from seven different parental lines of commercial White Leghorn layer flocks from three independent breeders were inoculated with a naturally occurring avian leukosis virus (ALV) containing an ALV-B envelope and an ALV-J long terminal repeat (LTR) termed ALV-B/J. Additional groups of chickens from the same seven parental lines were inoculated with ALV-B. Chickens were tested for ALV viremia and antibody at 0, 4, 8, 16, and 32 wk postinfection. Chickens from all parental lines studied were susceptible to infection with ALV-B with 40%-100% of inoculated chickens positive for ALV at hatch following embryo infection. Similarly, infection of egg layer flocks with the ALV-B/J recombinant virus at 8 days of embryonation induced tolerance to ALV with 86%-100% of the chickens viremic, 40%-75% of the chickens shedding virus, and only 2/125 (2%) of the chickens producing serum-neutralizing antibodies against homologous ALV-B/J recombinant virus at 32 wk postinfection. In contrast, when infected with the ALV-B/J recombinant virus at hatch, 33%-82% of the chickens were viremic, 28%-47% shed virus, and 0%-56% produced serum-neutralizing antibodies against homologous ALV-B/J recombinant virus at 32 wk postinfection. Infection with the ALV-B/J recombinant virus at embryonation and at hatch induced predominately lymphoid leukosis (LL), along with other common ALV neoplasms, including erythroblastosis, osteopetrosis, nephroblastomas, and rhabdosarcomas. No incidence of myeloid leukosis (ML) was observed in any of the commercial White Leghorn egg layer flocks infected with ALV-B/J in the present study. Data suggest that the parental line of commercial layers may influence development of ALV-B/J-induced viremia and antibody, but not tumor type. Differences in type of tumors noted in the present study and those noted in the field case where the ALV-B/J was first isolated may be attributed to differences in the genetics of the commercial layer flock in which ML was first diagnosed and the present commercial layer flocks tested in the present study.

Animals↗
PubMed2006

Influence of diet type on the inclusion of plant origin active substances on morphological and histochemical characteristics of the stomach and jejunum walls in chicken.

Three hundred and thirty-six 1-day-old male Hubbard HI-Ye broiler hybrids, kept in battery cages, were fed with diets based on maize (groups I and II) or wheat and barley (groups III and IV) and supplemented with or without plant extract (XT* 100 mg/kg) containing 5% carvacrol, 3% cinnamaldehyde and 2% of capsicum oleoresin. The morphological and histochemical examinations were carried out on days 21 and 42 of bird's age. The middle part of glandular part of the stomach and 30 mm long segment from the central part of the small intestine (jejunum) were taken out and then prepared for morphometrical and histochemical assays. Mobilization of mucocytes in superficial epithelium of the glandular stomach and increased secretion of neutral mucopolysaccharides and small amounts of sialomucins with or without local cell disruption with releasing of large amounts of mucus were observed in both 'grain' groups of 21-day-old birds fed with extract. In some animals, particularly those fed mixtures with plant extract, the folds of the proventriculum mucosa were fused into large, unshaped structures. In groups fed with plant extract the mucus secretion intensity and accumulation inside cells of the gastrointestinal mucosa were slightly higher. Morphological changes on gastrointestinal mucosa observed in young chickens fed XT were reduced in older animals. The results of this study showed that the increased releasing of large amounts of mucus and the creation of a thick layer of mucus on glandular stomach and wall of jejunum in chickens fed diets with plant extract could suggest villi-related protective properties of the use of the carvacrol, cinnamaldehyde and capsaicin mixture. This can explain the reduced possibility of adhesion to epithelium and number of Escherichia coli, Clostridium perfringes and fungi in the intestinal content of bird fed with XT supplemented diet. In morphometrical parameters of depth of jejunum crypt and height of villi, the influence of kind of grain and extract supplementation was observed in 21-day-old chickens only. The significant interaction between higher jejunum wall villi layer was observed only in chickens fed on maize diet supplemented with plant extract.

Animal Feed↗
PubMedDate not supplied

Intestinal nutrient uptake measurements and tissue damage: validating the everted sleeves method.

The reliability of methods for nutrient uptake measurements across the intestinal epithelium relies on the integrity of the mucosal epithelium and the enterocytes. We tested effects of tissue handling during the "everted sleeves method" on the length of intestinal villi, the surface magnification, the circumference of the gut, and the thickness of the muscle layer in sunbirds (Nectarinia osea), chicken (Gallus gallus), and mice (Mus domesticus). The sunbird has thin and delicate intestinal villi that are greatly affected by the everted sleeves method. After eversion and incubation, villi lost 30% of their original length. The severe tissue damage coincides with uptake measurements for glucose that were an order of magnitude lower than in other nectar-feeding (nectarivorous) birds of similar body size. Tissue handling during the everted sleeves method had significant effects on morphometric parameters of chicken and mouse intestines, but on a light-microscopical level, the tissue integrity and the cytology of the enterocytes were not altered. Therefore, we think that the everted sleeves method renders reliable and reproducible measurements of nutrient uptake in those species. We conclude that a histological evaluation is necessary to assess the reliability of the method before it is applied to adults or to the developmental stage of any species.

Animals↗
PubMed1977

The phospholipid content of ejaculated fowl and turkey spermatozoa.

Chicken and turkey spermatozoal lipids were separated into acidic and non-acidic fractions by DEAE cellulose column chromatography. The phospholipid composition of each fraction was examined by thin-layer chromatography, followed by phosphorus analysis. Chicken sperm phospholipid comprised 38.21% phosphatidyl choline, 9.04% phosphatidal choline, 12.62% phosphatidyl ethanolamine, 8.04% phosphatidal ethanolamine, 8.28% sphingomyelin, 9.76% phosphatidyl serine, 6.5% phosphatidyl inositol, and 7.49% cardiolipin. Turkey sperm phospholipid comprised 34.15% phosphatidyl choline, 7.14% phosphatidal choline, 15.61% phosphatidyl ethanolamine, 11.34% phosphatidal ethanolamine, 9.91% sphingomyelin, 8.83% phosphatidyl serine, 4.80% phosphatidyl inositol, and 8.22% cardiolipin.

Animals↗