Multiple perineuriomas in chicken (Gallus gallus domesticus)

Intraneural perineurioma is an extremely rare condition characterized by perineurial cell proliferation within peripheral nerve (PN) sheaths. In the veterinary field, this entity has been reported only in a dog. We examined multiple enlargements of PNs in 11 chickens (Gallus gallus domesticus) (9 Japanese bantams and 2 specific pathogen-free White Leghorn), which were inoculated with an avian leukosis virus (ALV) causing so-called fowl glioma. All chickens clinically exhibited progressive leg paralysis. Lumbosacral plexus, brachial plexus, and/or spinal ganglion were commonly affected, and these nerves contained a diffuse proliferation of spindle cells arranged concentrically in characteristic onion bulb-like structures surrounded by residual axons and myelin sheaths. The spindle cells were immunohistochemically negative for S-100alpha/beta protein. Electron microscopy revealed that these cells were characterized by short bipolar cytoplasmic processes, occasional cytoplasmic pinocytotic vesicles, and discontinuous basal laminae. These features are consistent with those of intraneural perineurioma. Furthermore, the specific sequence of the ALV was detected in the PN lesions of 8/11 (73%) birds by polymerase chain reaction. These results indicate that the multiple intraneural perineuriomas of chicken may be associated with the ALV-A causing fowl glioma.     

Gallus gallus domesticus: Paratenic host of Angiostrongylus vasorum

Angiostrongylus vasorum, a parasite of the cardiorespiratory system in canids, has a heteroxenous biological cycle in which the intermediate hosts are terrestrial and aquatic mollusks. Generally, canids become infected by ingesting the intermediate host or paratenic hosts, such as amphibians, that contain infective larvae (L3). However, there are no reports of birds as paratenic hosts of A. vasorum. To evaluate the susceptibility and viability of Gallus gallus domesticus as a paratenic host of A. vasorum, 17 Cobb chickens were randomly divided into two groups. The animals in group A were inoculated with third stage larvae of A. vasorum, and those in group B ate snails inoculated with A. vasorum L3. At 30 days post-infection, the chickens were killed, and the muscles and organs were placed in a pepsin–HCl solution (1% HCl (37%), 1% pepsin) for 3 h in an oven at 40 °C to recover the L3. In group A, 1863 L3 were recovered per chicken. In group B, 2585 L3 were recovered. A dog that ingested organs and tissues from a chicken from group A released first-stage larvae of A. vasorum in its feces 51 days after infection; the dynamics of this process were monitored for 107 days, when treatment with 25 mg fenbendazole/kg body weight was performed for 21 days. Chickens nourished with infected snails or with infective L3 may be a source of infection for dogs indicate that G. gallus is a potential paratenic host for this parasite.     

Metastatic melanomas in young broiler chickens (Gallus gallus domesticus)

Four young broiler chickens affected by multiple melanotic tumors are described. Grossly, there were multiple tumors composed of melanocytes within the skin, skeletal muscle, and multiple visceral organs. Tumors ranged from flattened macules to masses that extensively replaced viscera. Microscopically, melanocytes were often well pigmented, and while there was moderate nuclear anisokaryosis, mitotic rates were low. Immunohistochemical staining of some melanomas with antibodies to S100 proteins, Melan-A, vimentin, or neuron-specific enolase after bleaching of tumor cells with potassium permanganate revealed lack of immunostaining of tumor cells with antibodies to S100, strong positive staining of tumor cells for neuron-specific enolase, moderate staining with antibodies to vimentin, and faint staining for Melan-A. Only neuron-specific enolase staining was evident in unbleached tumor cells. Attempts to identify exogenous avian leukosis viruses in these tumors were unsuccessful.     

Postnatal development of central corneal thickness in chicks of Gallus gallus domesticus

Objective To investigate the changes in corneal thickness that occur during maturation of the Gallus gallus domesticus chick eye over the first 450 days of life. Animals studied Twenty‐nine chicks, of which 12 were males and 17 were females. Procedures The central corneal thickness (CCT) was measured by ultrasonic pachymetry from hatch until 450 days of age. Segmented regression was applied to capture the two phases observed in the CCT plotted against age. Eye and gender were also included in the model. Results Mean CCT values initially decreased, with the lowest point being reached at around 12 days of age. CCT then gradually increased as the chick matured. At 70 days of age the animals have completed corneal development and reached the plateau value of 0.242 ± 0.0002 mm. CCT differences between gender or between left and right eyes were not statistically significant. Prediction equations for mean CCT according to the bird's age are presented. Conclusions There is an initial decrease in corneal thickness until approximately 12 days of age, which presumably mirrors maturation of corneal endothelial cell function. The pattern of changes in corneal thickness during the first phase of development of the chick CCT was similar to the one reported for dogs and humans. However, a unique feature of the development of CCT in chicks is that after reaching a plateau at 70 days corneal thickness did not significantly change over the remainder of the study period. Additionally, unlike in humans and dogs, there is no gender difference for corneal thickness in chicks.     

Ontogeny of brain temperature regulation in chicks (Gallus gallus domesticus)

1. Development of brain temperature regulation was studied in the domestic fowl (Gallus gallus domesticus) from hatching to 21 d of age. 2. Body and brain temperature at hatching were relatively low compared with adult levels. However, both were effectively regulated at ambient temperatures of 30 and 35 degrees C, with only a minor difference between the 2 temperatures. 3. Body and brain temperature increased as a power function of age at significantly different rates, approaching adult levels at around 10 d of age and resulting in a linear increase in body-to-brain temperature difference with age. 4. The results indicated the existence of different patterns of post-hatching development of brain temperature regulation in relation to the degree of precocity of a species.     

Experimental stimulation of eosinophil production in the domestic fowl (Gallus gallus domesticus)

A method has been devised to produce eosinophilia in birds experimentally. Multiple intraperitoneal injections of bovine serum albumin (BSA) produced a greater response than horse serum in young adult fowls, and injections of 2 ml BSA were more effective than injections of 0.2 ml. The highest eosinophilic responses were obtained with injections of BSA together with aluminium hydroxide. Thymectomy had little effect on eosinophil numbers following horse serum injections but irradiation produced a depressed response. Horse serum that had been heated to 56 degrees C for 30 minutes to inactivate complement and to denature proteins, including possible horse IgE, induced an eosinophilic response in 50 per cent of birds compared with only 14 per cent with unheated horse serum. Furthermore, when the former birds were reinjected after a rest period of 13 weeks, the eosinophilic response followed a similar curve as before but a higher proportion of birds responded. Birds aged over two years did not give a good eosinophilic response after horse serum stimulation. There was no consistent correlation between raised IgE levels and eosinophil numbers. Tolerance to horse serum was detected in some birds using a radial immunodiffusion technique. Analyses of blood plasma from birds with eosinophilia showed a significant increase in total amino acids compared with normal birds.     

Physiological and behavioural responses associated with feather removal in Gallus gallus var domesticus

Electroencephalographic, cardiovascular and behavioural parameters were examined in Gallus gallus var domesticus in response to feather removal. The progressive removal of feathers resulted in marked changes in the bird's behaviour from an alert agitated response following the initial removals to periods of crouching immobility following successive removals. During the periods of immobility the birds showed a high amplitude low frequency EEG pattern and successive removals resulted in a progressive increase in the total duration of this activity in the two minutes after removal. The heart rate response to feather removal was variable whereas the blood pressure always increased and this increase was followed by a gradual return to pre-stimulus levels. There were no consistent cardiovascular responses related to the immobility. It was concluded that feather removal is likely to be painful to the bird and feather removal by flockmates can be categorised as a welfare problem.     

Discrimination between individual humans by domestic fowl (Gallus gallus domesticus).

1. We demonstrate that Barred-Rock and Isa-Brown hens can discriminate between the presence of 2 different humans and use this information as a cue for whether or not to make an operant response. 2. This demonstration in domestic fowl, the first of its kind in any avian subject, is consistent with a growing body of evidence that many species, including agricultural animals, are surprisingly adept at differentiating between humans. 3. Such a discriminative ability carries considerable implications for issues related to husbandry, production and welfare.     

Morphological study of the caecal epithelium of the chicken (Gallus gallus domesticus L.)

1. The structure of the chicken caecal epithelium has been investigated at macroscopic and microscopic levels (scanning and transmission electron microscopy). 2. Morphological data distinguish three regions in the caecum: proximal, with well developed villi, but smaller and less numerous than those present at mid-jejunum; medial, with longitudinal folds and small villi, and distal, with longitudinal and transverse folds and small villi similar to those of the medial region. 3. Microvilli of enterocytes from the tip of the villus of the proximal caecum are shorter and thinner than jejunal microvilli; microvilli of medial and distal regions are poorly developed. 4. There is a decrease in microvillus surface area along the villus axis as a result of the progressive decrease of microvillus length from the tip of the villus to the crypt, both in the proximal caecum and jejunum. In tip of the villus, the amplification of apical surface due to microvilli is 24, 12.7 and 14 times in proximal, medial and distal caecum, respectively, while in the jejunum the amplification factor is 33.1. 5. The higher development of proximal caecal apical surface supports the view that this region is better adapted for the absorption of nutrients that the other caecal regions.     

Cardiovascular tolerance of intravenous lidocaine in broiler chickens (Gallus gallus domesticus) anesthetized with isoflurane

ObjectiveTo determine the cardiovascular effects of lidocaine infused intravenously (IV) in broiler chickens.Study designTwo phase study: Phase 1, randomized up-and-down study to determine effective dose 50 (ED₅₀) for lidocaine; Phase 2, prospective randomized study to determine the cardiovascular effects of lidocaine.AnimalsSeventeen Ross-708 broiler chickens (Gallus gallus domesticus) [11 chickens (Phase 1) and 6 chickens (Phase 2)], weighing 2.6–4.3 kg.MethodsAfter induction of anesthesia with isoflurane and placement of monitoring equipment including invasive blood pressure, chickens were administered lidocaine IV. During Phase 1, using an up-and-down design, each animal received a variable dose selected based on the response of the previous animal. During Phase 2, each animal was administered 6 mg kg⁻¹ of lidocaine IV over 2 minutes. Clinically irrelevant cardiovascular effects were defined as a relative decrease of heart rate (HR) and mean blood pressure (MAP) <30% subsequent to IV lidocaine administration. The ED₅₀ was defined as the dose rate that would cause clinically irrelevant cardiovascular depression in 50% of the population.ResultsDuring Phase 1, using an up-and-down study design (n = 11), the ED₅₀ of lidocaine was determined to be 6.30 mg kg⁻¹ and 6.22 mg kg⁻¹ (95% confidence interval, 5.30–7.13 mg kg⁻¹), when calculated by Dixon's up-and-down method, and logistic regression, respectively. During Phase 2, following infusion of lidocaine (6 mg kg⁻¹), no clinically relevant effects on HR or MAP were detected in any animal.Conclusions and clinical relevancePrevious reports state that the dose of lidocaine used in birds should be =4 mg kg⁻¹. In this study, 6 mg kg⁻¹ of lidocaine injected IV was not associated with adverse cardiovascular effects. These results suggest that the dose of 4 mg kg⁻¹ can be exceeded, at least in chickens, and opens the possibility of other therapeutic uses for lidocaine in birds.     

Cardiovascular tolerance of intravenous bupivacaine in broiler chickens (Gallus gallus domesticus) anesthetized with isoflurane

Objective

To determine the median effective dose (ED₅₀) of intravenous (IV) bupivacaine associated with a 50% probability of causing clinically relevant cardiovascular effects [defined as 30% change in heart rate (HR) or mean arterial pressure (MAP)] in chickens anesthetized with isoflurane.

Utilisation of energy substrates in treadmill-exercised domestic fowl (Gallus gallus domesticus): blood glucose

1. Blood glucose concentration, glucose turnover and gas exchange were monitored in adult male domestic fowl at rest and during 90 min of continuous treadmill exercise. 2. During exercise oxygen consumption increased to about three times its resting value. Blood glucose concentration fell by 26% by the end of exercise. 3. Blood glucose turnover was not altered by exercise and oxidation showed only a moderate increase (35%). Glucose oxidation accounted for 23% of the total energy expenditure at rest and this value fell to 10% during exercise. At the same time the plasma free fatty acid concentration rose to three times its resting value suggesting an increased mobilisation of this substrate. 4. It is concluded that during exercise of this relatively moderate intensity glucose is a quantitatively minor fuel for the working muscles.     

Expression profile of myostatin mRNA during the embryonic organogenesis of domestic chicken (Gallus gallus domesticus)

Myostatin is a potent growth and differentiation factor involved in skeletal muscle tissue formation in vertebrates. However, recent studies in chicken embryo suggested that the myostatin was expressed even before the establishment of myogenic lineage. No studies have thus far been reported in birds to define the role of myostatin during the embryonic organogenesis. The present experiment was designed for studying the expression profiles of myostatin mRNA in the chicken liver, heart, brain, and intestine during their morphogenesis, using real-time PCR. The myostatin mRNA expression was significantly upregulated in liver during E15-E18. Similar results were observed during the development of chicken heart. In brain, the expression of myostatin was upregulated from E4 onwards. In intestine, the expression of myostatin was significantly increased many folds on E9-E18. Therefore, the increase in myostatin expression might be related to the growth of liver and heart on days E12-E18; morphogenesis and growth of brain during E15-E18; and morphogenesis and differentiation of intestine during E9-E18. In the present study, the tissue-specific expression of myostatin gene in chicken is similar to fishes, but different from that in mammals. Further, the inspection of chicken genome also suggested that there is no differentiation of GDF-8 and -11. A recent finding suggests that the chicken myostatin gene is closely related to mammals than fishes. Therefore, we propose that the chicken myostatin gene might have diverged in its function between teleosts and mammals. Indeed it is possible that its function might have only become fully differentiated to serve as a control of muscle mass in mammals.     

Production potentials of native chickens (Gallus gallus domesticus L.) of Western Visayas, Philippines

Poultry genetic resources diversity serves as a reservoir of genes adaptable to local conditions, production, resource utilization, and production that are compatible with consumer preferences for meat and egg products. This study was, therefore, conducted to determine the production potentials of native chickens in Western Visayas, Philippines. A total of 270 raisers were interviewed and 810 chickens were characterized. These numbers were divided equally among the provinces of Aklan, Antique, Capiz, Guimaras, Iloilo, and Negros Occidental. The data collected were analyzed using one-way analysis of variance and significant differences were determined using the Duncan’s Multiple Range Test. Results show that native chickens from Aklan had the highest (P?<?0.01) hatching percentage (93.10?±?1.67 %) and oldest (P?<?0.01) slaughter/marketing age (23.56?±?1.03 weeks). Those from Guimaras had the biggest (P?<?0.01) egg (42.69?±?0.87 g) and heaviest slaughter/marketing weight (920.00?±?22.72 to 924.44?±?23.01 g); the shortest (P?<?0.01) clutch interval (77.87?±?4.14 days) was observed from those in Iloilo. Those from Antique had the highest (P?<?0.01) survival rate from 1 day old to a slaughter/marketing age of 52.48?±?1.83 %. The adult live weight ranged from 1.27?±?0.04 to 1.62?±?0.04 kg with those from Aklan as the lowest (P?<?0.01) while those from Guimaras were the highest. Thus, the observed variations in reproductive and growth performances of native chickens from this region expressed their potentials for genetic improvement toward production.     

Let me sleep! Welfare of broilers (Gallus gallus domesticus) with disrupted resting behaviour

Perching is important for broiler welfare, however, hampered by body weight. In a mixed flock, resting behaviour and location were compared between three broiler hybrids (Rowan Ranger, Hubbard CYJA57 &; Ross 308; n?=?100/hybrid), differing in growth. Rearing was in a large littered pen (1.84 birds/m²), with perches. Behaviour and position was observed in focal birds on daytime and as group scans on daytime (days 11, 45, 61 and 80) and night-time (days 63, 70 and 77). Birds were slaughtered at 84 days and accumulated mortality in fast-growing birds was 20% and 2% in slow-growing. Resting frequency did not differ though fast-growing broilers perched less and lower, at night (P?P?P?相似文献   

Influence of intensive and extensive breeding on lactic acid bacteria isolated from Gallus gallus domesticus ceca

In the present study, lactic acid bacteria (LAB) from the cecum of chickens bred either under intensive (commercial broilers) or extensive (free-range) conditions were isolated, identified and some of their probiotic characteristics determined. The LAB identified by 16S-23S rRNA PCR-ARDRA were mainly of Lactobacillus species and to a lesser extent of Enterococcus spp. for all animals. Free-range chickens showed a higher presence of Lactobacillus acidophilus while Lactobacillus reuteri and Lactobacillus johnsonii were more frequently recovered from commercial broilers. Lactobacillus crispatus was found only in commercial broilers, Lactobacillus vaginalis and Lactobacillus agilis only in free-range chickens and Lactobacillus salivarius in both types. Enterococcus isolates from ceca of commercial broilers showed a higher resistance to antimicrobial drugs. Lactobacillus isolates from free-range chickens presented a higher frequency of in vitro antagonistic activity against selected pathogens than from commercial broilers. All LAB isolates had predominantly non-hydrophobic surfaces, but with variations depending on age of the chickens and breeding conditions. Animal breeding caused variation on composition, antimicrobial susceptibility, antagonistic activity and surface hydrophobicity of LAB from chicken cecum. LAB isolates from ceca of free-range chickens have potential as probiotic agents, which may be used in the future as replacing the use of antimicrobials as growth promoters.     

红色原鸡及其研究进展

本文就红色原鸡的生态习性、人工驯养及杂交利用、种质资源保护等方面的研究做一简单概述.