888 resultados para DOMESTIC-FOWL


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1. A total of 240 Shaver White and 240 ISA Brown pullets that had been reared in multi-bird cages on a 10-h photoperiod, and maintained at a light intensity of 3 or 25 lux, or changed from 3 to 25 lux or from 25 to 3 lux at 9 or 16 weeks of age, were moved into individual-bird cages at 20 weeks and transferred to 15-h photoperiods at 25 lux. 2. In both breeds, birds transferred from 3 to 25 lux at 16 or 20 weeks laid significantly more eggs than birds maintained on the brighter intensity from one day or increased to it at 9 weeks. 3. Mean egg weight, shell deformation, albumen height, feed intake and body weight gain in lay were not significantly affected by the light intensity treatments during the rearing period. There was, however, a small, but significant, negative correlation of egg numbers with mean egg weight, although this only partially explained the difference in egg numbers. The differences in egg production were unrelated to rate of sexual maturation.

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This experiment evaluated the growth of breast and leg muscle fibers of domestic fowl raised in two enclosure sizes (SE: Small Enclosure, 1.125 m2/10 birds; LE: Large Enclosure, 5.25 m2/10 birds). In breast muscles, the number of fibers per area decreased over time and higher values were observed in broilers housed in SE compared to LE. The fiber size increased with age and was greater in LE than SE at 56 days of age, suggesting greater hypertrophic growth of fibers in breast muscle for broilers maintained in LE. In leg muscles, the muscle cross-sectional area was greater for broilers raised in LE than SE at 56 days of age and decreased from 42 to 56 days of age in broilers raised in SE, suggesting leg muscle atrophy in these birds. The Fast Glycolytic (FG), Fast Oxidative-Glycolytic (FOG) and Slow Oxidative (SO) fibers grew until 42 days of age in both enclosure sizes. The area of FOG fibers was greater in broilers raised in LE than those in SE at 28 and 56 days of age; in LE-raised broilers, the SO area was greater at 28, 42 and 56 days of age, suggesting that the muscles of broilers housed in LE are more oxidative. The BW gain was greater for broilers raised in LE than SE, whereas BW, feed intake and feed conversion were not influenced by enclosure size. Thus, the enclosure space affected hypertrophic growth and metabolic characteristics of breast and leg muscle fibers. © Asian Network for Scientific Information, 2012.

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Coccidiosis of the domestic fowl is a worldwide disease caused by seven species of protozoan parasites of the genus Eimeria. The genome of the model species, Eimeria tenella, presents a complexity of 55-60 MB distributed in 14 chromosomes. Relatively few studies have been undertaken to unravel the complexity of the transcriptome of Eimeria parasites. We report here the generation of more than 45,000 open reading frame expressed sequence tag (ORESTES) cDNA reads of E. tenella, Eimeria maxima and Eimeria acervulina, covering several developmental stages: unsporulated oocysts, sporoblastic oocysts, sporulated oocysts, sporozoites and second generation merozoites. All reads were assembled to constitute gene indices and submitted to a comprehensive functional annotation pipeline. In the case of E. tenella, we also incorporated publicly available ESTs to generate an integrated body of information. Orthology analyses have identified genes conserved across different apicomplexan parasites, as well as genes restricted to the genus Eimeria. Digital expression profiles obtained from ORESTES/EST countings, submitted to clustering analyses, revealed a high conservation pattern across the three Eimeria spp. Distance trees showed that unsporulated and sporoblastic oocysts constitute a distinct clade in all species, with sporulated oocysts forming a more external branch. This latter stage also shows a close relationship with sporozoites, whereas first and second generation merozoites are more closely related to each other than to sporozoites. The profiles were unambiguously associated with the distinct developmental stages and strongly correlated with the order of the stages in the parasite life cycle. Finally, we present The Eimeria Transcript Database (http://www.coccidia.icb.usp.br/eimeriatdb), a website that provides open access to all sequencing data, annotation and comparative analysis. We expect this repository to represent a useful resource to the Eimeria scientific community, helping to define potential candidates for the development of new strategies to control coccidiosis of the domestic fowl. (C) 2011 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

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Cover title.

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Includes bibliographical references.

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1. Embryos of the domestic fowl have been partially sterilised by injecting the drug busulphan into 24-h incubated eggs. 2. Some of these embryos were injected with primordial germ cells (PGCs) after 55 h of incubation to attempt to repopulate the gonads. 3. Primordial germ cells transfected with a defective retrovirus containing the reporter gene lac Z were shown to settle in these sterilised gonads. 4. Quantitative histology of 6-d embryos showed that busulphan produced 75% sterilisation but that PGCs could repopulate these gonads. 5. The technique of producing such germ line chimaeras is of value in studying cell kinetics, gonad differentiation and the production of transgenics.

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Horses; their varieties, breeding, and management in health and disease -- The hog; his originand varieties : management with a view to profit, and treatment under disease -- The hive and the honey-bee; with plain directions for obtaining a considerable annual income from this branch of rural economy -- Domestic fowl and ornamental poultry; their natural history, origin, and treatment in health and disease -- The cow: dairy husbandry and cattle breeding / by M. M. Milburn.

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Multiple lineages of Brazilian strains from 2007 to 2008 of avian infectious bronchitis virus (IBV) were detected in flocks of breeders, broilers, and layers. Organs samples from 20 IBV-positive flocks with variable clinical signs were submitted to the partial amplification of S gene (nucleotides 726-1071) of IBV. Fifteen of the 20 sequenced strains segregated in a unique Brazilian cluster subdivided in three subclusters (Brazil 01, 02, and 03). Whereas three strains could be classified as Massachusetts (Mass) genotype, the remaining two strains, originating from flocks with reproductive and respiratory disorders, grouped within the 4/91-793B genotype, a genotype that has not been detected before in Brazil. The potential relevance of the findings to the poultry industry is discussed because the low level of identity of the sequenced part of the S gene from 17 of 20 detected field strains and the vaccines of the Massachusetts serotype used suggest that the level of cross-protection by the Massachusetts vaccines might be low.

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The relationship between sperm velocity and individual age, size, body condition and fluctuating asymmetry was investigated in Alpine whitefish Coregonus fatioi. The fish analysed belonged to one among several sympatric whitefish populations of Lake Thun, Switzerland, which are characterized by a high prevalence of gonad alterations. Therefore, sperm velocity data were also tested for a link between gonad deformation and sperm swimming speed. Sperm velocity was significantly lower in larger-grown individuals and in individuals of higher body condition. As expected, sperm velocity was higher in males with higher levels of fluctuating asymmetry, but it did not significantly vary with male age. Moreover, variation in sperm velocity was found to be significantly higher in individuals showing some types of gonad alterations but it did not significantly correlate with the presence of other types of alterations. (C) 2007 The Authors Journal compilation (C) 2007 The Fisheries Society of the British Isles.

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Ovarian follicle development is primarily regulated by an interplay between the pituitary gonadotrophins, LH and FSH, and ovary-derived steroids. Increasing evidence implicates regulatory roles of transforming growth factor-beta (TGF beta) superfamily members, including inhibins and activins. The aim of this study was to identify the expression of mRNAs encoding key receptors of the inhibin/activin system in ovarian follicles ranging from 4 mm in diameter to the dominant F1 follicle (similar to 40 turn). Ovaries were collected (n=16) from inid-sequence hens maintained on a long-day photoschedule (16h of light:8 h of darkness). All follicles removed were dissected into individual granulosa and thecal layers. RNA was extracted and cDNA synthesized. Real-time quantitative PCR was used to quantify the expression of niRNA encoding betaglycan, activin receptor (ActR) subtypes (type-I, -IIA and -IIB) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH); receptor expression data were normalized to GAPDH expression. Detectable levels of ActRI, -IIA and -IIB and the inhibin co-receptor (betaglycan) expression were found in all granulosa and thecal layers analysed. Granulosa ActRI mRNA peaked (P < 0(.)05) in 8-9(.)9 mm follicles, whereas ActRIIA rose significantly from 6-7(.)9 mm to 8-9(.)9 nun, before filling to F3/2; levels then rose sharply (3-fold) to F1 levels. Granulosa betaglycan niRNA expression rose 3-fold from 4-5(.)9 min to 8-9(.)9 mm, before falling 4-fold to F3/2; levels then rose sharply (4-fold) to F1 levels. ActRIIB levels did not vary significantly during follicular development. Thecal ActRI mRNA expression was similar from 4-7(.)9 mm then decreased significantly to a nadir at the F4 position, before increasing 2-fold to the F1 (P < 0(.)05). Although thecal ActRIIB and -IIA expression did not vary significantly from 4 nim to F3, ActRIIB expression increased significantly (2-fold) from F3 to F1 and ActIIA, increased 22-fold from F2 to F1 (P < 0(.)05). Thecal betaglycan fell to a nadir at F6 after follicle selection; levels then increased significantly to F2, before filling similar to 50% in the F I. In all follicles studied expression of betaglycan and ActRI (granulosa: 1-0(.)65, P < 0-001, n=144/group; theca: r=0(.)49, P < 0-001, n=144/group) was well correlated. No significant correlations were identified between betaglycan and ActRIIA or -IIB. Considering all follicles analysed, granulosa mRNA expression of betaglycan, ActRI ActRIIA and ActRIIB were all significantly lower than in corresponding thecal tissue (betaglycan, 11(.)4-fold; ActRIIB, 5(.)1-fold; ActR(.) 3-8-fold: ActRIIA, 2(.)8-fold). The co-localization of type-I and -II activin receptors and betaglycan on granulosa and thecal cells are consistent with a local auto/paracrine role of inhibins and activins in modulating ovarian follicle development, selection and progression in the domestic fowl.

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Secretion of LH and FSH from the anterior pituitary is regulated primarily by hypothalamic GnRH and ovarian steroid hormones. More recent evidence indicates regulatory roles for certain members of the transforming growth factor beta (TGF beta) superfamily including inhibin and activin. The aim of this study was to identify expression of mRNAs encoding key receptors and ligands of the inhibin/activin system in the hen pituitary gland and to monitor their expression throughout the 24-25-h ovulatory cycle. Hens maintained on long days (16 h light/8 h dark) were killed 20, 12, 6 and 2 h before predicted ovulation of a midsequence egg (n = 8 per group). Anterior pituitary glands were removed, RNA extracted and cDNA synthesized. Plasma concentrations of LH, FSH, progesterone and inhibin A were measured. Real-time quantitative PCR was used to quantify pituitary expression of mRNAs encoding betaglycan, activin receptor (ActR) subtypes (type I, IIA), GnRH receptor (GnP,H-R), LH beta subunit, FSH beta subunit and GAPDH. Levels of mRNA for inhibin/activin beta A and beta B subunits, inhibin alpha subunit, follistatin and ActRIIB mRNA in pituitary were undetectable by quantitative PCR (< 2 amol/reaction). Significant changes in expression (P < 0.05) of ActRIIA and betaglycan mRNA were found, both peaking 6 h before ovulation just prior to the preovulatory LH surge and reaching a nadir 2 h before ovulation, just after the LH surge. There were no significant changes in expression of ActRI mRNA throughout the cycle although values were correlated with mRNA levels for both ActRIIA (r=0.77; P < 0.001) and betaglycan (r=0.45; P < 0.01). Expression of GnRH-R mRNA was lowest 20 h before ovulation and highest (P < 0.05) 6 h before ovulation; values were weakly correlated with betaglycan (r=0.33; P=0.06) and ActRIIA (r=0.34; P=0.06) mRNA levels. Expression of mRNAs encoding LH beta and FSH beta subunit were both lowest (P < 0.05) after the LH surge, 2 h before ovulation. These results are consistent with an endocrine, but not a local intrapituitary, role of inhibin-related proteins in modulating gonadotroph function during the ovulatory cycle of the hen, potentially through interaction with betaglycan and ActRIIA. In contrast to mammals, intrapituitary expression of inhibin/activin subunits and follistatin appears to be extremely low or absent in the domestic fowl.

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Secretion of LH and FSH from the anterior pituitary is regulated primarily by hypothalamic GnRH and ovarian steroid hormones. More recent evidence indicates regulatory roles for certain members of the transforming growth factor beta (TGF beta) superfamily including inhibin and activin. The aim of this study was to identify expression of mRNAs encoding key receptors and ligands of the inhibin/activin system in the hen pituitary gland and to monitor their expression throughout the 24-25-h ovulatory cycle. Hens maintained on long days (16 h light/8 h dark) were killed 20, 12, 6 and 2 h before predicted ovulation of a midsequence egg (n = 8 per group). Anterior pituitary glands were removed, RNA extracted and cDNA synthesized. Plasma concentrations of LH, FSH, progesterone and inhibin A were measured. Real-time quantitative PCR was used to quantify pituitary expression of mRNAs encoding betaglycan, activin receptor (ActR) subtypes (type I, IIA), GnRH receptor (GnP,H-R), LH beta subunit, FSH beta subunit and GAPDH. Levels of mRNA for inhibin/activin beta A and beta B subunits, inhibin alpha subunit, follistatin and ActRIIB mRNA in pituitary were undetectable by quantitative PCR (< 2 amol/reaction). Significant changes in expression (P < 0.05) of ActRIIA and betaglycan mRNA were found, both peaking 6 h before ovulation just prior to the preovulatory LH surge and reaching a nadir 2 h before ovulation, just after the LH surge. There were no significant changes in expression of ActRI mRNA throughout the cycle although values were correlated with mRNA levels for both ActRIIA (r=0.77; P < 0.001) and betaglycan (r=0.45; P < 0.01). Expression of GnRH-R mRNA was lowest 20 h before ovulation and highest (P < 0.05) 6 h before ovulation; values were weakly correlated with betaglycan (r=0.33; P=0.06) and ActRIIA (r=0.34; P=0.06) mRNA levels. Expression of mRNAs encoding LH beta and FSH beta subunit were both lowest (P < 0.05) after the LH surge, 2 h before ovulation. These results are consistent with an endocrine, but not a local intrapituitary, role of inhibin-related proteins in modulating gonadotroph function during the ovulatory cycle of the hen, potentially through interaction with betaglycan and ActRIIA. In contrast to mammals, intrapituitary expression of inhibin/activin subunits and follistatin appears to be extremely low or absent in the domestic fowl.

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Ovarian follicle development is primarily regulated by an interplay between the pituitary gonadotrophins, LH and FSH, and ovary-derived steroids. Increasing evidence implicates regulatory roles of transforming growth factor-beta (TGF beta) superfamily members, including inhibins and activins. The aim of this study was to identify the expression of mRNAs encoding key receptors of the inhibin/activin system in ovarian follicles ranging from 4 mm in diameter to the dominant F1 follicle (similar to 40 turn). Ovaries were collected (n=16) from inid-sequence hens maintained on a long-day photoschedule (16h of light:8 h of darkness). All follicles removed were dissected into individual granulosa and thecal layers. RNA was extracted and cDNA synthesized. Real-time quantitative PCR was used to quantify the expression of niRNA encoding betaglycan, activin receptor (ActR) subtypes (type-I, -IIA and -IIB) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH); receptor expression data were normalized to GAPDH expression. Detectable levels of ActRI, -IIA and -IIB and the inhibin co-receptor (betaglycan) expression were found in all granulosa and thecal layers analysed. Granulosa ActRI mRNA peaked (P < 0(.)05) in 8-9(.)9 mm follicles, whereas ActRIIA rose significantly from 6-7(.)9 mm to 8-9(.)9 nun, before filling to F3/2; levels then rose sharply (3-fold) to F1 levels. Granulosa betaglycan niRNA expression rose 3-fold from 4-5(.)9 min to 8-9(.)9 mm, before falling 4-fold to F3/2; levels then rose sharply (4-fold) to F1 levels. ActRIIB levels did not vary significantly during follicular development. Thecal ActRI mRNA expression was similar from 4-7(.)9 mm then decreased significantly to a nadir at the F4 position, before increasing 2-fold to the F1 (P < 0(.)05). Although thecal ActRIIB and -IIA expression did not vary significantly from 4 nim to F3, ActRIIB expression increased significantly (2-fold) from F3 to F1 and ActIIA, increased 22-fold from F2 to F1 (P < 0(.)05). Thecal betaglycan fell to a nadir at F6 after follicle selection; levels then increased significantly to F2, before filling similar to 50% in the F I. In all follicles studied expression of betaglycan and ActRI (granulosa: 1-0(.)65, P < 0-001, n=144/group; theca: r=0(.)49, P < 0-001, n=144/group) was well correlated. No significant correlations were identified between betaglycan and ActRIIA or -IIB. Considering all follicles analysed, granulosa mRNA expression of betaglycan, ActRI ActRIIA and ActRIIB were all significantly lower than in corresponding thecal tissue (betaglycan, 11(.)4-fold; ActRIIB, 5(.)1-fold; ActR(.) 3-8-fold: ActRIIA, 2(.)8-fold). The co-localization of type-I and -II activin receptors and betaglycan on granulosa and thecal cells are consistent with a local auto/paracrine role of inhibins and activins in modulating ovarian follicle development, selection and progression in the domestic fowl.

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Anthropologists and cultural geographers have long accepted that animals play an important role in the creation of human cultures. However, such beliefs are yet to be embraced by archaeologists, who seldom give zooarchaeological data much consideration beyond the occasional economic or environmental reconstruction. In an attempt to highlight animal remains as a source of cultural information, this paper examines the evidence for the changing relationship between people and wild animals in Iron Age and Roman southern England. Special attention is given to ‘exotic’ species — in particular fallow deer, domestic fowl and the hare — whose management increased around AD 43. In Iron Age Britain the concept of wild game reserves was seemingly absent, but the post-Conquest appearance of new landscape features such as vivaria, leporaria and piscinae indicates a change in worldview from a situation where people seemingly negotiated with the ‘wilderness’ and ‘wild things’ to one where people felt they had the right or the responsibility to bring them to order. Using Fishbourne Roman Palace as a case study, we argue that wild and exotic animals represented far more than gastronomic treats or symbols of Roman identity, instead influencing the way in which people engaged with, traversed and experienced their surroundings.