			Home About us Contact

Domestic Chicken (domestic + chicken)

Distribution by Scientific Domains

Life Sciences	80%

Selected Abstracts

Vascularization of the Fleshy Comb in the Domestic Chicken

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005
B. Vollmerhaus
Up to now little is known about the vascularization of the chicken fleshy comb (crista carnosa). In order to evaluate the vascularization of the crista carnosa of the cook (breed White Leghorn), corrosion casts were created by injecting Plastoid into the internal carotid as described by Schummer (1951). Specimens were investigated by stereomicroscopy and scanning electron microscopy (SEM). Generally the dermis is highly vascularized by two capillary networks, which are localized beneath the epithelium and beneath the dermal papillas. The dense subepithelial network is characterized by the presence of sinusoid vessels. In the subcutaneous plexus numerous arteriovenous anastomoses of different types occur. Additionally there are arteriovenous anastomoses between the main vessels reaching the indentations of the comb. Our results show the presence of superficial and dense capillary networks and arteriovenous anastomoses are the anatomical basis for the functions of the chicken comb in mating behaviour and thermoregulation. Reference, Schummer, A. 1951: Simplified method for plastoid corrosion. Anat. Anaz. 98, 288,290. [source]

Behavioral regulators in the brain of neonatal chicks

ANIMAL SCIENCE JOURNAL, Issue 3 2007
Mitsuhiro FURUSE
ABSTRACT Domestic chickens are precocial and therefore have relatively well-developed processes at hatch. As a result, neonatal chicks grow well at hatch with no parental care. The regulation of food intake in animals, including domestic birds, is complicated. Just after hatching, neonatal chicks find their food by themselves and they can control their food intake. Recently, prolactin releasing peptide and gonadotropin-inhibitory hormone were confirmed as central orexigenic factors in the neonatal chick. Both peptides have a common structure as RFamide peptides. On the other hand, vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide, both belonging to the glucagon superfamily, were recognized as inhibitory. Broiler chicks have either a greater capability to acclimatize to novel environments, or a blunted hypothalamus-pituitary-adrenal axis compared with layer chicks. These differences are explained by higher melatonin concentrations in the pineal gland and other parts of the brain of broiler chicks since melatonin attenuates the stress response. Stressful behavior in chicks can be attenuated by neurotransmitters or by nutrients such as creatine, phosphatidylserine, L-serine and (-)-epigallocatechin gallate. It is suggested that the regulation of behavior is somewhat specific and can be attenuated by some manipulation in neonatal chicks. [source]

2,3,4,7,8-pentachlorodibenzofuran is a more potent cytochrome P4501A inducer than 2,3,7,8-tetrachlorodibenzo- p -dioxin in herring gull hepatocyte cultures

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2010
Jessica C. Hervé
Abstract Concentration-dependent effects of 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), and 2,3,7,8-tetrachlorodibenzofuran (TCDF) on cytochrome P4501A (CYP1A) induction were determined in primary cultures of embryonic herring gull (Larus argentatus) hepatocytes exposed for 24,h. Based on the concentration that induced 50% of the maximal response (EC50), the relative potencies of TCDD and TCDF did not differ by more than 3.5-fold. However, also based on the EC50, PeCDF was 40-fold, 21-fold, and 9.8-fold more potent for inducing ethoxyresorufin- O -deethylase (EROD) activity, CYP1A4 mRNA expression, and CYP1A5 mRNA expression than TCDD, respectively. The relative CYP1A-inducing potencies of PeCDF and of other dioxin-like chemicals (DLCs) in herring gull hepatocytes (HEH RePs), along with data on concentrations of DLCs in Great Lakes herring gull eggs, were used to calculate World Health Organization toxic equivalent (WHO-TEQ) concentrations and herring gull embryonic hepatocyte toxic equivalent (HEH-TEQ) concentrations. The analysis indicated that, when using avian toxic equivalency factors (TEFs) recommended by the WHO, the relative contribution of TCDD (1.1,10.2%) to total WHO-TEQ concentration was higher than that of PeCDF (1.7,2.9%). These results differ from the relative contribution of TCDD and PeCDF when HEH RePs were used; PeCDF was a major contributor (36.5,52.9%) to total HEH-TEQ concentrations, whereas the contribution by TCDD (1.2,10.3%) was less than that of PeCDF. The WHO TEFs for avian species were largely derived from studies with the domestic chicken (Gallus gallus domesticus). The findings of the present study suggest that it is necessary to determine the relative potencies of DLCs in wild birds and to re-evaluate their relative contributions to the biochemical and toxic effects previously reported in herring gulls and other avian species. Environ. Toxicol. Chem. 2010;29:2088,2095. © 2010 SETAC [source]

Gender-related changes in the avian vasotocin system during ontogeny

MICROSCOPY RESEARCH AND TECHNIQUE, Issue 1 2001
Aleksandr Jurkevich
Abstract The arginine vasotocin (AVT) system of the avian brain includes a sexually dimorphic part that extends from the caudal part of preoptic region through the medial part of the bed nucleus of stria terminalis (BSTm) to the lateral septum. It is composed of the parvocellular neurons located in the BSTm and the dense innervation of the medial preoptic region and lateral septum. In this part of the brain, AVT expression is stronger in males than in females in a few bird species investigated to date. This review focuses on the ontogeny of sexual differences in the vasotocinergic system of two gallinaceous species, domestic chicken and Japanese quail, and on the role of gonadal hormones in organizing during development and maintaining in adulthood these differences. Parvocellular AVT neurons become discernible in the BSTm of males and females during the second half of embryonic development. These cells undergo a profound and irreversible sexual differentiation during ontogenetic development. Recent findings demonstrate a dual role of estrogens in the organization and activation of sex differences in the AVT system. During the embryonic period of ontogeny, estrogens differentiate the AVT system in a sexually dimorphic manner in parallel with the differentiation of sexual behavior, while in adulthood estrogens, locally produced from testosterone in the male brain, activate AVT synthesis in the BSTm. The sexually dimorphic part of the AVT system is sensitive to a number of abiotic factors such as light, temperature, and water availability. It is suggested that sex dimorphic vasotocinergic systems could be implicated in processes of social recognition in various behavioral contexts. Microsc. Res. Tech. 55:27,36, 2001. © 2001 Wiley-Liss, Inc. [source]

Association of a Glu92Lys substitution in MC1R with extended brown in Japanese quail (Coturnix japonica)

ANIMAL GENETICS, Issue 3 2006
N. J. Nadeau
Summary We investigated melanocortin 1 receptor (MC1R) as a candidate locus for the Extended brown phenotype in quail, in which there is a general darkening throughout the plumage. An initial screen of variation in MC1R in Extended brown and in wild-type quails revealed two polymorphic non-synonymous sites. One of these sites, a G-to-A substitution leading to a Glu92Lys mutation, was perfectly associated with plumage phenotype; all Extended brown birds were homozygous for Lys92. Co-segregation of the Glu92Lys mutation with the Extended brown phenotype was confirmed in 24 progeny of an E/e+ × E/e+ cross. Glu92Lys is likely to be the causative mutation for the increased melanism in Extended brown, given that the same mutation is associated with melanic plumage in many breeds of domestic chicken, as well as in a wild passerine bird (the bananaquit, Coereba flaveola) and laboratory mice. Interestingly, the increase in melanization with the Glu92Lys mutation is less marked in quails than in most other birds and mammals. Phylogenetic results indicate that the Glu92Lys mutation has independently occurred in quail and chicken lineages. [source]

Red jungle fowl (Gallus gallus) as a model for studying the molecular mechanism of seasonal reproduction

ANIMAL SCIENCE JOURNAL, Issue 3 2009
Hiroko ONO
ABSTRACT Photoperiodism is an adaptation mechanism that enables animals to predict seasonal changes in the environment. Japanese quail is the best model organism for studying photoperiodism. Although the recent availability of chicken genome sequences has permitted the expansion from single gene to genome-wide transcriptional analysis in this organism, the photoperiodic response of the domestic chicken is less robust than that of the quail. Therefore, in the present study, we examined the photoperiodic response of the red jungle fowl (Gallus gallus), a predecessor of the domestic chicken, to test whether this animal could be developed as an ideal model for studying the molecular mechanisms of seasonal reproduction. When red jungle fowls were transferred from short-day- to long-day conditions, gonadal development and an increase in plasma LH concentration were observed. Furthermore, rapid induction of thyrotropin beta subunit, a master regulator of photoperiodism, was observed at 16 h after dawn on the first long day. In addition, the long-day condition induced the expression of type 2 deiodinase, the key output gene of photoperiodism. These results were consistent with the results obtained in quail and suggest that the red jungle fowl could be an ideal model animal for the genome-wide transcriptional analysis of photoperiodism. [source]

Central regulation of food intake in the neonatal chick

ANIMAL SCIENCE JOURNAL, Issue 2 2002
Mitsuhiro FURUSE
ABSTRACT Regulating food intake is complicated in animals including domestic birds. Just after hatching, neonatal chicks find their food by themselves and they can control food intake, since domestic chicken belongs to the precocial type of avian species. Thus, domestic chickens have relatively well-developed mechanisms of food-intake control at hatching. While many aspects of food-intake regulation in chickens appear similar to that in mammals, there are some responses that are unique to chickens. For instance, some neurotransmitters such as neuropeptide Y (NPY), orexin-A, orexin-B, motilin, melanin-concentrating hormone (MCH), galanin, growth hormone releasing factor (GRF) and ghrelin stimulate feeding in mammals. Only NPY strongly stimulates food intake in birds similar to that observed in mammals; however, both orexins, motilin, MCH and galanin failed to alter food intake of the chick. Moreover, GRF and ghrelin suppressed feeding of chicks. On the other hand, cholecystokinin (CCK), gastrin, glucagon-like peptide-1 (GLP-1), corticotropin-releasing factor (CRF), histamine, ,-melanocyte stimulating hormone (,-MSH), leptin and bombesin are known to suppress feeding in mammals. These responses are similar to those of mammals except for leptin. Therefore, the inhibitory mechanisms for feeding are well conserved in chicks. [source]

The domestic chicken in the Tylos burials of Bahrain

ARABIAN ARCHAEOLOGY AND EPIGRAPHY, Issue 2 2003
Kevin C. MacDonald
Four out of fifteen burials from the Tylos period (c.200 BC , AD 200), presented by Toft Jensen in this number of AAE, contained bones of the domestic chicken (Gallus gallus) and represent the earliest remains of that species found on the island of Bahrain. [source]

The odour of pyrazine increases the egg mass of domestic chickens (Gallus gallus domesticus L.)

JOURNAL OF ZOOLOGY, Issue 3 2002
Anat Barnea
Abstract Forty leghorn chickens at the commencement of egg laying, were divided into two groups, each with 10 females and 10 males. One group was exposed to the odour of synthetic pyrazine (2-methoxy-3-isobutylpyrazine) for 16 weeks while the other acted as a control. During the first 4 weeks the hens exposed to pyrazine odour laid significantly fewer eggs (unfertilized) than the controls, but thereafter both groups laid a similar number. Mean egg mass of the pyrazine exposed hens was significantly (P= 0.012) greater (5.5%) than that of the control group. No significant difference was found in body mass or eggshell thickness. Similarly, there were no consistent significant differences between groups in oestrogen and testosterone concentrations in the blood of females and males, respectively. No pyrazine could be detected in cloacal extracts. The experiment shows that an external odour can affect the internal reproductive system of the chicken. It is suggested that the pyrazine-engendered increase in egg mass involves neuroendocrine regulation within the hypothalamus rather than hormonal interactions ,downstream' of the brain. [source]