Gallus Gallus VERIFIED
The noncoding control region of the mitochondrial DNA of various gallinaceous birds was studied with regard to its restriction fragment length polymorphism (RFLP) and sequences of the first 400 bases. Tandem duplication of the 60-base unit was established as a trait unique to the genus Gallus, which is shared neither by pheasants nor by quails. Unlike its close ally Gallus varius (green junglefowl), the red junglefowl Gallus gallus is a genetically very diverse species; the 7.0% sequence divergence was seen between those from Thailand (G. g. gallus and G. g. spadiceus) and the other from the Indonesian island of Java (G. g. Bankiva). Furthermore, the divergence increased to 27.83% if each transversion is regarded as an equivalent of 10 transitions. On the other hand, a mere 0.5-3.0% difference (all transitions) separated various domestic breeds of the chicken from two G. g. gallus of Thailand, thus indicating a single domestication event in the area inhabited by this subspecies of the red junglefowl as the origin of all domestic breeds. Only transitions separated six diverse domesticated breeds. Nevertheless, a 2.75% difference was seen between RFLP type I breeds (White Leghorn and Nagoya) and a RFLP type VIII breed (Ayam Pelung). The above data suggested that although the mitochondrion of RFLP type V was the main contributor to domestication, hens of other RFLP types also contributed to this event.
Maropitant citrate is a synthetic neurokinin-1 receptor antagonist and substance P inhibitor used for control of emesis in dogs in cats. Maropitant citrate is used empirically in birds, despite a lack of pharmacokinetic data in avian species. The objective of this study was to determine the pharmacokinetic profile of a single dose of maropitant citrate 1 and 2 mg/kg subcutaneously (SC) in eight Rhode Island Red hens (Gallus gallus domesticus). A crossover study design was used with 1-week washout between trials. Blood samples were collected over 36 h after drug administration. Plasma concentrations were measured using liquid chromatography-tandem mass spectrometry and pharmacokinetic parameters were determined via non-compartmental analysis. The mean maximum plasma concentration, time to maximum concentration, and elimination half-life following 1 and 2 mg/kg SC were 915.6 312.8 ng/ml and 1195.2 320.2 ng/ml, 0.49 0.21 h and 1.6 2.6 h, and 8.47 2.24 h and 8.58 2.6 h, respectively. Pharmacokinetic data suggests doses of 1 or 2 mg/kg SC may be administered every 12-24 h to maintain above target plasma concentration similar to dogs (90 ng/ml). These data provide a basis for further investigation of maropitant citrate pharmacokinetics and pharmacodynamics in birds.
Mitochondrial DNA (mtDNA) sequences remain the most widely used for phylogenetic analysis in birds. A major limitation of mtDNA sequences, however, is that mitochondria genes are inherited as a single linkage group. Here we describe the use of a 540-bp DNA sequence corresponding to the G3 domain of Gallus gallus nuclear aggrecan gene (AGCI) for phylogenetic analysis of the main groups of Galliformes including Phasianidae, Numididae, and Odontophoridae. We also included species from Cracidae and Megapodiidae which are considered by some as Craciformes and others, including here as Galliformes. The uncorrected sequence divergence of the G3 fragments ranges from 1% among the grouses to 36% between some of the distant groups within Galliformes. These sequences contain 39-48% AT nucleotides and the ratios of transition versus transversion are above 1.5 in majority of the comparisons. Using G3 sequences from an Anseriform, Oxyura jamaicensis, as out-groups, phylogenetic trees were obtained using maximum parsimony and distance algorithms and bootstrap analyses. These trees were consistent with those described using Avian sarcoma and leucosis virus gag genes and those from amino acid sequences of hemoglobin and lysozyme c. Our data also support relationships among Galliformes which were defined using mtDNA sequences. In addition to the general support of the five main families of Galliformes, our data are also consistent with previous work that showed Francolinus africanus and Gallus gallus are in the same clade and that Tetraoninae is a well-supported monophyletic subfamily within Phasianidae. The results presented here suggest that the AGC1 sequences meet the criterion of novel nuclear DNA sequences that can be used to help resolve the relationships among Galliformes.
The nucleus isthmi pars magnocellularis (Imc) and pars parvocellularis (Ipc) influence the receptive field structure of neurons in the optic tectum (TeO). To understand better the anatomical substrate of isthmotectal interactions, neuronal morphology and connections of Imc were examined in chicks (Gallus gallus). Cholera toxin B injection into TeO demonstrated a coarse topographical projection from TeO upon Imc. Retrogradely labeled neurons were scattered throughout Imc and in low density within the zone of anterogradely labeled terminals, suggesting a heterotopic projection from Imc upon TeO. This organization differed from the precise homotopic reciprocal connections of Ipc and the nucleus isthmi pars semilunaris (SLu) with TeO. By using slice preparations, extracellular biotinylated dextran amine injections demonstrated a dense projection from most neurons in Imc upon both Ipc and SLu. Intracellular filling of Imc neurons with biocytin revealed two cell types. The most common, Imc-Is, formed a widely ramifying axonal field in both Ipc and SLu, without obvious topography. A less frequently observed cell type, Imc-Te, formed a widely ramifying terminal field in layers 10-12 of TeO. No neurons were found to project upon both Ipc/SLu and TeO. Both types possessed local axon collaterals and flat dendritic fields oriented parallel to the long axis of Imc. Imc neurons contain glutamic acid decarboxylase, which is consistent with Imc participating in center-surround or other wide-field inhibitory isthmotectal interactions. The laminar and columnar pattern of isthmotectal terminals also suggests a means of interacting with multiple tectofugal pathways, including the stratified subpopulations of tectorotundal neurons participating in motion detection.
Most scientists agree that the Southeast Asian Red Junglefowl (gallus gallus) is the primary wild ancestor of chickens. However, because DNA studies show that the Red Junglefowl lacks the gene for yellow skin (and shanks) it is believed that some point, hybridization with the Grey Junglefowl (Gallus sonnaratii) of India has occurred. The body structure of the Indian Gamebird (Cornish) and the Brahmas of China gives physical evidence of Grey Jungle- fowl influence. The tail carriage of the breed Sumatra indicates genetic contributions of the SriLanka Junglefowl (Gallus lafayetti). No doubt the Green Junglefowl (Gallus varius) has also contributed to modern chickens.
Malate dehydrogenase (MDH) functions as a catalyst for the NAD+/NADH-dependent reversible reaction between malate and oxaloacetate. The mitochondrial form of the enzyme (MDH2) is important in the citric acid cycle, a key part of aerobic metabolism. Previous studies into avian MDH2 have focused on studying enzyme gel mobility between taxonomic families, activity differences between migratory and non-migratory species, and activity differences of a species at high versus low altitudes. Individual enzyme kinetics and structural data on the wild-type MDH2, however, are not documented. A cDNA library is utilized to obtain the gene for Gallus gallus (chicken). The Gibson Cloning assembly was used to insert the MDH2 gene into the pET28(a)+ expression vector for expression of the protein in E. coli cells. Initial experiments to test expression conditions indicated that codon optimization may be required. Once optimal expression of the enzyme is achieved, the Kcat, Vmax, and Km values of wild-type MDH2 can be determined. Additionally, protein modeling software was employed to predict the 3D structure of the Gallus gallus and other avian species mitochondrial MDH proteins. These comparisons not only give insight on how differences in the amino acid sequence affect the structure, but they provide clues as to what mutations to the Gallus gallus expression vector may mimic the MDH2 enzyme of another avian species providing future research directions.
In this study, we assessed phenotypic variation in the development of two sexually size dimorphic traits. We then partitioned this phenotypic variation into genetic and environmental influences using multigenerational quantitative genetics techniques based on restricted maximum likelihood (REML) methods. These methods, developed by animal breeders, are becoming increasingly popular in behavioural ecology and evolutionary biology (reviewed in Kruuk, 2004). We used data from three generations of red junglefowl (Gallus gallus L.) to assess quantitative genetic patterns in mass gain and tarsus growth. We explored the extent to which growth trajectories were heritable and genetically integrated between traits and among ages. We also asked whether patterns of quantitative genetic variance were distinct in males and females and to what extent genetic correlations existed between the sexes.
TRAV (red), TRDV (yellow), TRAJ (light green), TRDJ (dark green), and TRDD (brown) gene segments are shown numbered by their corresponding location in order across the locus. TRAC (light blue) and TRDC (dark blue) are also indicated. TRAV segments are designated with a subgroup number followed by a period and a designated number according to their genomic location. Transcriptional orientation is indicated by the direction of the arrow on each gene segment. Arrows are not in proportion to the actual gene sizes. Interchangeably used V gene segments are indicated with a φ. Broken lines indicate the sequence gaps in the study, which is supplemented by the currently available Gallus gallus genome assembly (Galgal 4) accordingly. Syntenic and some unrelated genes are presented as gray boxes. 041b061a72