SEARCH · Search PubMed

Results for “FOWLS, DOMESTIC”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,603 records · Page 89Linked to original sources

PubMedDate not supplied

Cranial teratomas in two domestic ducks (Anas platyrhynchos domesticus).

Teratomas are rare tumors in domestic fowl, and none have been reported in the cranial area of ducks. Clinical signs and gross and microscopic findings associated with a cranial teratoma in two domestic ducks are reported. One tumor arose within the cranial vault and was associated with neurologic signs. The other tumor was subcutaneous and invaded the parietal bone but did not extend into the brain. Both tumors were tridermic.

Animals↗

PubMed1994

[Detection, significance and control of paramyxoviruses in birds].

Infection, disease and mortality due to various paramyxoviruses currently occur fairly frequently in both domestic fowl and in captive and free-living birds. These viruses are therefore of economic and ecologic significance, and may also cause zoonoses. The current legal status of the detection and control of paramyxovirus-associated diseases or epidemics are described. Prophylactic vaccination against Newcastle disease using live and inactivated vaccines, as required by the fowl disease regulations, remains of great importance in maintaining health and productivity of the fowl. Correct immunisation also includes checking the effectiveness using serological methods.

Animals↗

PubMed1990

Gordon memorial lecture. Vaccines and vaccination--past, present and future.

1. Immunisation was first practised as early as the 10th century when small doses of smallpox material administered by unusual routes were used to immunise against smallpox. The procedure was introduced into England in the early part of the 18th century. 2. The next major development was the use by Jenner of cowpox to vaccinate against smallpox in the late 18th century. 3. Some eighty years later came the classic studies of Pasteur developing vaccines for fowl cholera, anthrax and rabies. 4. The studies of Jenner and Pasteur established the major principles of vaccination which are in use to this day. 5. The major viral diseases of the domestic fowl were recognised during the 1920s and 1930s and in most cases vaccines were developed within 5 years of the discovery of the viral nature of the cause of each disease. 6. The desirable properties of poultry vaccines required by the user and producer are not completely fulfilled by currently available vaccines. 7. There is a need to use the opportunities provided by modern biotechnology and immunology to search for and develop vaccines that better fulfil the desirable properties of poultry vaccines. 8. There are a number of strategies available for the development of novel vaccines, some of which are appropriate for the needs of poultry vaccines.

Animals↗

PubMed1995

["Breeding for distress" in fowl].

During the last hundred years the fancying and breeding of exhibition poultry became very popular as free time activity. Certain breeding standards were set, and the aim of actual breeding endeavours is to meet these standards through selective breeding. Not only were serious defects established as standard qualities (e.g. domestic ducks with feather crests, rumplessness, and ear-tufts in the domestic fowl), but certain distinctive marks were changed into excessive formations (e.g. pigeon breeds with large, cauliflower-like wattles, or enlarged crops and severe behaviour changes). Accurate analysis of such breeding efforts shows that these breeds are to be called defective and abnormal in the sense of section 11b of the German protection of animals legislation. Whether an increased embryonic mortality, especially during the hatching period, constitutes a condemnable state of cruelty against is recently being discussed. Criticised are also standard features which handicap, in varying degrees, certain functional systems of the natural behaviour patterns. Section 11b of the German protection of animal legislation in its present wording is definitely no sufficient mean to control the contemporary excess in breeding of domestic animals.

Animal Welfare↗

PubMed1980

Differentiation of sympathetic and enteric neurons of the fowl embryo in grafts to the chorio-allantoic membrane.

Sympathetic cells (adrenergic neurons, SIF cells and chromaffin cells) and enteric neurons differentiate from migratory cells derived from the neural crest. The development of these cell types was studied in chorio-allantoic membrane (CAM) grafts, using combinations of tissue from domestic fowl embryos. Neural anlagen (neural tube and crest) of the vagal, cervico-thoracic and lumbo-sacral axial levels were equally capable of sympathetic differentiation, but this required somitic tissue for its significant expression. However, the vagal somites possessed only slight sympathogenic activity, thereby accounting for the negligible contribution of the vagal neural crest to the sympathetic nervous system. The same three levels of the neural anlage could furnish enteric neurons when combined directly with the aneuronal colo-rectum. However, the scale of this line of differentiation varied with the level of origin of the neural anlage, in contrast to the apparent equivalence in the ability to diffentiate as sympathetic cells. The density of enteric neurons in combinations with the vagal neural anlage was estimated as 60 times greater than the neuron density in combinations with the cervico-thoracic neural anlage. The lumbo-sacral neural anlage gave results similar to those of the cervico-thoracic level. Moreover, neural crest-derived pigment cells, positioned ectopically in the wall of the colo-rectum, were rare in combinations with the vagal neural anlage, but common in grafts with the other levels. When tested physiologically, the colo-rectum grown with the vagal neural anlage showed non-adrenergic, non-cholinergic inhibitory nervous activity in addition to the expected cholinergic excitatory responses. The neurons derived directly from vagal neural anlagen were similar to those that had reached the colo-rectum via their normal migratory pathways, when studied in terms of histological appearance, density of distribution and physiological responses.

Allantois↗

PubMed1995

Blockade of beta-adrenoceptor in control of blood pressure in fowl.

Several avian species show elevated blood pressure (BP) and spontaneous atherogenesis in the aorta and other large arteries. The BP appears to be influenced by age, sex (higher in males), environment, and diet in some species. We reported previously that mean aortic pressure and heart rate, but not plasma renin activity (PRA), of conscious female domestic fowl were markedly reduced by propranolol. In the present study, we aimed to determine in conscious roosters whether 1) hypotension evoked by atenolol or practolol, which selectively inhibit cardiac beta-receptors in mammals, is more potent than that evoked by propranolol, and 2) the renin-angiotensin (ANG) system and/or catecholamines are involved in beta-adrenoceptor antagonist-induced hypotension. Mean arterial pressure (171.2 +/- 3.5 mmHg) and heart rate (281 +/- 4 beats/min) of chronically cannulated roosters (n = 38) were markedly reduced by acute infusion or repeated injections (14 days) of propranolol, atenolol, or practolol, but not by SQ-14,225 (ANG-converting enzyme inhibitor) or [Sar1, Thr8]ANG II (nonselective ANG receptor antagonist). None of the beta-adrenoceptor blockers, however, showed cardioselectivity. The resting PRA of conscious roosters (1.27 +/- 0.09 ng.ml-1.h-1, n = 38) was low and did not change significantly after chronic or acute treatment with beta-adrenoceptor blockers except for a slight decrease induced by practolol. PRA increased after SQ-14,225. The plasma levels (pg/ml) of norepinephrine (701.9 +/- 76.0), epinephrine (337.2 +/- 57.1), and dopamine (299.1 +/- 39.0) of conscious roosters were further increased by propranolol. Practolol also increased dopamine significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗

PubMed1987

Calcium participation in thyroid function in fowl (Gallus domesticus).

The effects of the calcium antagonists ethyleneglycol-bis-(beta-aminoethylether)-N,N,N',N'-tetraace tic acid (EGTA), cobalt chloride (CoCl2), and magnesium chloride (MgCl2) on the concentrations of plasma thyroxine (T4) and triiodothyronine (T3) and on the basal and stimulated release of T4 from incubated thyroid glands have been determined in the domestic fowl. Plasma T4 levels were consistently reduced 2 hr after the administration of each calcium antagonist, although only EGTA and CoCl2 lowered the concentration of plasma total calcium. Concentrations of plasma T3 were increased following MgCl2 treatment but reduced after CoCl2 administration. The basal release of T4 by incubated thyroid glands was reduced following in vivo EGTA and CoCl2 treatment, but increased after MgCl2 injection. The addition of bovine thyroid stimulating hormone (TSH, 200 mU) to the incubation consistently stimulated in vitro T4 release, although the magnitude of the stimulation was increased following in vivo EGTA or CoCl2 treatment and reduced after MgCl2 administration. These results demonstrate the involvement of calcium dependent mechanisms in the control of T4 release in fowl.

Animals↗

PubMed1983

Effects of food deprivation, strain, diet and age on feeding responses of fowls to intravenous injections of cholecystokinin.

This paper presents new information about inhibitory effects of intravenous injections of cholecystokinin-octapeptide (CCK-8) on feeding activity in birds, with particular reference to variation in motivational state. With increasing food deprivation (0, 1, 2 or 3 h) before injection, doses of 2 and 8 micrograms/kg CCK-8 became progressively less effective in suppressing feeding of domestic fowls. As with mammals, latency to feed was shorter, and subsequent feeding activity greater, with deprived than with undeprived birds. Fowls of broiler (meat-type) and layer strains, which have different absolute food requirements but similar relative (per kg body weight) requirements, did not differ in their feeding responses to injections of 1, 8 and 16 micrograms/kg CCK-8. Food intake of fowls fed on a diet diluted with 40% powdered cellulose was suppressed less by the same three doses of CCK-8 than that of birds fed on undiluted food. This may have been because birds with the more bulky diluted food had to spend a greater proportion of time feeding. Broiler chicks aged 2 and 6 weeks, which may have different blood-brain resistance to circulating CCK and which have different relative food requirements, did not differ in their feeding responses to injections of 2 and 8 micrograms/kg CCK-8. These results do not satisfy one of the criteria proposed for demonstrating the action of a satiety agent, that feeding should be suppressed in a consistent manner regardless of motivational state. An alternative explanation for the apparent satiating properties of CCK-8 is suggested, based on similarities in their time-course, and dependence on deprivation level, to abnormal gastrointestinal responses with similar doses of the peptide.

Aging↗

PubMed2003

Distribution of N-acetylneuraminic acid and sialylglycan in eggs of the Silky fowl.

1. The distribution of sialic acid in the eggs of original Silky fowl was investigated. The sialic acid contents of the yolk, albumen and the chalaza of a single egg were 205.2, 11.96 and 0.83 mg, respectively. 2. The sialic acid content of the yolk of Silky eggs was 11.5-fold higher than that of a conventional domestic fowl yolk. 3. Sialic acid isolated from Silky yolk was entirely N-acetylneuraminic acid (NeuAc). No N-glycolylneuraminic acid or O-acetyl containing sialic acid was observed. 4. The structure of the major sialylglycan in Silky egg yolk was determined to be a disialyl-biantennary chain in which the NeuAc residues were alpha2-6 linked to glucose. No alpha2-3 linkage was observed. 5. Thus, the Silky fowl's egg provides an excellent source of NeuAc and sialylglycan.

Animals↗

PubMed1984

Plasma hormones (arginine vasotocin, prolactin, aldosterone, and corticosterone) in relation to hydration state, NaCl intake, and egg laying in fowls.

This review surveys our latest research dealing with the involvement of arginine vasotocin (AVT), the avian antidiuretic hormone, and other hormones in the regulation of water and salt balance in fowl. We examined the effect of dehydration, salt loading, high- and low-salt diets, and oviposition on plasma hormone levels and analyzed them in light of our knowledge of avian osmoregulatory responses to changes in water and salt balance. Gradual dehydration and hyperosmotic loading in domestic fowl revealed consistent differences in the AVT response between groups adapted to low- and high-NaCl diets. In birds on a low-NaCl diet the sensitivity of the AVT release was significantly higher than in birds on a high-NaCl diet. These results support the concept that the link between osmotic and volume regulation is established via varying sensitivity of the AVT release. We determined the half-life of the AVT in fowls (6.3 min), a value similar to that of ADH in mammals. We found that during oviposition, plasma AVT increases by a factor of four over the normal level, a magnitude consistent with the maximal responses revealed in osmotic stimulations. We have shown that as long as drinking water is available, heat exposure has no effect on the plasma osmotic constituents and the regulatory hormones. However, combined dehydration and heat exposure resulted in pronounced osmoregulatory responses integrated with the thermoregulatory responses to maintain water and salt balance without jeopardizing the birds' ability to cope with the thermoregulatory demands.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldosterone↗

PubMedDate not supplied

[Erythrocyte insulin receptors in the ontogeny of chickens].

Specific binding of 125I-insulin by the erythrocytes was studied in the chick embryos, chicken and adult fowl. The binding was shown to decrease during ontogenesis. The maximal level of binding was observed in the chick embryos. Within a month after hatching, it decreased to the level of adult fowl due, mainly, to the decrease in the number of receptors per erythrocyte. This phenomenon can be accounted for both by the increase of insulin content in blood with age and the age changes of the population of erythrocytes. It is proved that during ontogenesis of the domestic fowl the decrease of a portion of immature erythrocytes in the peripheral blood with age accounts for the dynamics of binding observed. At the same time the affinity of hormone receptors increased but the influence of this factor on the binding pattern was not leading.

Aging↗

PubMed2000

Do female broiler breeder fowl display a preference for broiler breeder or laying strain males in a Y-maze test?

In recent years, the commercial broiler breeder industry has reported problems of male aggression towards females [Millman, S.T., 1999. An investigation into extreme aggressiveness of broiler breeder males. Unpublished PhD Thesis, University of Guelph]. Although this aggression is shown by the males and is apparently a defect in their behaviour [Millman, S.T., Duncan, I.J.H., 2000. Strain differences in aggressiveness of male domestic fowl in response to a male model. Appl. Anim. Behav. Sci. 66, pp. 217-233], it is also possible that it stems in some way from the females. For example, broiler breeder females may not be receptive to male courtship advances, and may avoid males, thus causing frustration in otherwise normal males. The objective of this study was to examine mate preference by broiler breeder females and the effects of sexual experience on preference. A total of 24 mature, broiler breeder females were individually tested in a Y-maze, with females choosing between a broiler breeder male and a laying strain male. Females were tested using male models and tethered live males, both when the females were sexually inexperienced and after they had been housed with broiler breeder or laying strain males for 6 weeks.Females did not display a male-strain preference when tested with models, but sexually experienced females displayed some evidence of a preference for laying strain males in tests with live males, which did not reach statistical significance (P<0.10). Live males were a stronger attractant for sexually experienced females than were models (P<0.005). Individual females tested with the same pair of males showed different preferences, suggesting females used male behaviour as a basis for their choices, and not male morphology.In conclusion, we found no evidence that broiler breeder females inherently discriminate against broiler breeder males.

Journal Article↗

PubMed2002

Pre- and post-insemination episodes of sexual selection in the fowl, Gallus g. domesticus.

Although much attention has been recently directed to sexual selection arising after insemination from sexual promiscuity, little is known about the mechanisms determining reproductive success after insemination, and the way these mechanisms interact with each other and with selective mechanisms occurring before insemination: mate choice and mate acquisition. Here, we briefly review the findings of an on-going study investigating the mechanisms generating variation in reproductive success at both a pre- and a post-insemination stage in the domestic fowl. Female preference consistently favours socially dominant males before and after insemination. However, although social status mediates the number of sperm that a male inseminates into a female, dominant males may inseminate sperm of lower fertilising quality than their subordinates. We argue that mitochondrial genes may contribute to determine sperm quality, and speculate that the maternal control of mitochondrial genes may prevent sexual selection from operating on males, thus explaining both the lack of a positive correlation between social dominance and sperm quality and the maintenance of variation in male quality in the fowl.

Animals↗

PubMed2001

Maturation-dependent neointima formation in fowl aorta.

Fowl show spontaneous elevation of blood pressure (BP) and neointimal plaque formation in the abdominal aorta at young ages. Maturation/age-dependent modulation of vascular lesions and a causal relationship between elevated BP and neointima formation, however, have not been clarified. We therefore intended to characterize, first, maturation/age-dependent neointimal plaque formation and vascular lesions and, second, their relationship to BP elevation. The BP measured in conscious domestic fowl, Gallus gallus, White Leghorn breed, DeKalb strain, via an indwelling catheter inserted into the ischiadic artery, increased with maturation in males; and at plateau level, BP (mmHg) was significantly (P<0.01) higher in males (194.0+/-4.6, n=11) than in females (169.3+/-3.1, n=10). Neointimal plaques consisting of neointimal cells and abundant extracellular matrix appeared initially in the distal segment of the abdominal aorta (lesion-prone area) of chicks as early as 6 weeks old. The area (size) of neointimal plaques right above the ischiadic bifurcation increased with maturation, whereas the plaque area became smaller with some degenerative changes in adult birds. In some birds, diffuse subendothelial hyperplasia and more extensive plaque formation at the branching points of the aorta were observed. The plaque area appears to be larger in birds, particularly in males that have higher BP (r=0.68). The width of aortic smooth muscle (SM) layers, measured in regions with no plaque, increased with age, whereas the number of cells per unit of area decreased, suggesting that hypertrophy of vascular SM occurs in response to exposure of the vascular wall to high BP. The number of cells was significantly (P<0.01) higher in the plaque than in underlying aortic SM layers or in layers with no plaque formation. Both neointimal plaques and underlying SM layers are immunohistochemically positive for alpha SM actin, suggesting that neointimal cells are modulated SM cells, whereas the staining with SM myosin heavy chain antibody is low in neointimal plaques. Furthermore, plasma arginine levels dropped in accordance with the time of neointimal plaque formation, whereas plasma cholesterol levels showed an age-dependent increase. The results suggest that spontaneous development of neointimal plaques may be a consequence of exposure to high BP and associated local hemodynamic changes.

Actins↗

PubMed1988

Thyrotrophin-releasing hormone induces growth hormone secretion in adult hypothyroid fowl.

While thyrotrophin-releasing hormone (TRH) stimulated growth hormone (GH) secretion in adult anesthetized cockerels, the GH response was blocked in anesthetized birds pretreated with thyroxine (T4) or triiodothyronine (T3). Moreover, whereas GH secretion in conscious adult birds was poorly responsive to TRH stimulation, conscious birds made hypothyroid by goitrogen pretreatment (with propylthiouracil, methimazole, or thiourea) were responsive to TRH challenge. Basal circulating GH concentrations in the goitrogen-pretreated birds were also higher than in the vehicle-injected controls. Surgical thyroidectomy similarly increased the basal GH concentration in adult birds and promoted TRH-induced GH secretion. These results demonstrate inhibitory effects of the thyroid hormones on basal and stimulated GH secretion in adult domestic fowl and suggest that GH release in adults is partly under tonic thyroidal inhibition.

Animals↗

PubMed1988

Egg-laying pattern of the semi-domesticated helmeted guinea fowl (Numida meleagris galeata).

1. Studies on the egg laying pattern of the semi-domesticated helmeted guinea fowl showed that the birds laid eggs between 06.00 and 20.00 h local time (05.00 to 19.00 h GMT). 2. More (67.9%) were laid in the evenings (15.00 to 20.00 h) than at any other period. 3. There were two distinct periods in the reproductive cycle: a breeding season which began in April and ended in September, and a resting or non-breeding period between October and March. 4. Sequence length was predominantly of 4 eggs and July was the month of peak egg production.

Animals↗

PubMed1986

Reduced food intake following intracerebroventricular administration of a low molecular weight fraction of plasma from free-feeding fowl.

Plasma was collected from free-feeding Leghorn cockerels and partitioned by gel filtration into fractions of different molecular weight ranges. The individual fractions were then lyophilized and reconstituted to four times the original concentration. The plasma was administered to 10-week-old Leghorn cockerels via a stainless steel guide cannula, stereotaxically implanted into the lateral cerebral ventricle. Sated cockerels received 10 microliters intracerebroventricular (ICV) injections of one of the concentrated plasma fractions or of a control injection of artificial cerebrospinal fluid. Food and water intake were monitored following injection. Food intake was significantly decreased by the ICV injection of plasma fractions less than 1500 mol wt, whereas water consumption was not significantly different from that of the controls. The 1500 to 5000 mol wt fraction and the fraction above 5000 did not alter either food or water intake. These results suggest that the plasma of free-feeding domestic fowl contains a low molecular weight factor that is involved in the regulation of food intake.

Animals↗

PubMedDate not supplied

Prevalence and antibiogram of Campylobacter jejuni in domestic animals in rural Ghana.

A total of 134 samples of rectal and cloacal swabs taken from apparently healthy domestic animals that were in 43 of 76 homes located in rural Ghana were examined for Campylobacter jejuni. C. jejuni was isolated from 32.8% (44/134) of the animals. The highest isolation rate of 43.6% was from local domestic fowls, followed by goats (33.3%) and sheep (23%). This organism was not detected in the pigs, cats, and ducks. All 44 strains of this bacterium produced hydrogen sulphide and hydrolyzed hippurate; antibiogram on 24 strains showed resistance to cephalothin, cephalexin, and sulfamethoxazole/trimethoprim. C. jejuni biotype 2 is the prevailing strain in animals in the area studied.

Animals↗