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At least 145 records · Page 8Linked to original sources
PubMed1991

The onset of pain related behaviours following partial beak amputation in the chicken.

The number of pecks delivered by birds to an attractive visual stimulus was measured before and again 6, 26 and 32 h after partial beak amputation. There was a significant reduction in the number of pecks by birds 26 h after amputation but not at 6 h after. This reduction was considered to be a quantitative measure of pain related guarding behaviour. The results indicated the presence of a pain-free period immediately following amputation which may last in some birds for as long as 26 h.

Amputation, Surgical↗
PubMed1976

Sedimentation equilibrium studies on protein from kookaburra beak.

Fractionated samples of the soluble S-carboxymethyl proteins from kookaburra beak (Frenkel and Gillespie 1976) were examined by equilibrium sedimentation. The molecular weight was found to be 11,300 when the photoelectric scanning absorption optical system was employed and 13,700 when Rayleigh interference optics were used. Possible explanations for this difference are considered and it is concluded that it must arise from heterogeneity of the protein. Optical rotatory dispersion measurements indicate that the proteins probably exist as random coils in dilute aqueous buffer.

Animals↗
PubMedDate not supplied

Short beak: a new autosomal recessive semilethal mutation in Japanese quail.

Short break (SBK) is a new semilethal mutation of Japanese quail (Coturnix japonica). The SBK individuals are characterized externally by short breaks, shanks, and digits. The shank is also thicker than the wild type. The shape of the mutant beak does not show a parrotlike appearance, contrasting with that of other poultry chondrodystrophic mutants reported in the literature. Bones in the fore and hind limbs of the SBK mutant are also shorter than the wild types. The humerus and ulna in the wing are significantly thicker than the wild types. Other bones in the wing and leg show approximately the same thickness as the wild types. The majority of the SBK mutants die at the late embryonic stage. Some chicks can hatch with no assistance, but almost all die around 3 days of age. However, a part of the SBK individuals (5.3%, 8/151) reach sexual maturity and can reproduce. Genetic analyses revealed that the SBK mutation is controlled by an autosomal recessive gene. The proposed gene symbol is sbk. The sbk gene is allelic to the previously reported stumpy-limb (sl) gene that expresses a somewhat similar phenotype to the SBK.

Animals↗
PubMed1993

Laboratory diagnosis of psittacine beak and feather disease by haemagglutination and haemagglutination inhibition.

Simple and sensitive haemagglutination and haemagglutination inhibition assays were developed for psittacine beak and feather disease (PBFD) virus and serum antibody, respectively. The assays were used in the examination of samples from 73 birds clinically affected with PBFD. High antigen titres (log2 9 to log2 12) were detected in feathers, faeces and cloacal contents of PBFD-affected birds. Antigen was not detected in either faecal or feather samples from 20 normal galahs (Eolophus roseicapillus) and 9 normal sulphur crested cockatoos (Cacatua galerita). After kaolin treatment and haemadsorption of serum, haemagglutination inhibition (HI) antibody titres could not be detected in serum from 42 PBFD-affected birds, whereas serum HI titres from 64 normal psittacine birds ranged from less than log2 1 to log2 8. Serum and yolk HI antibody responses of 6 PBFD virus-inoculated layer hens were measured. Pre-inoculation chicken sera contained high concentrations of non-specific haemagglutination inhibitors (not detected in chloroform-extracted yolk), which were removed by kaolin treatment and haemadsorption.

Animals↗
PubMed1992

Ultrastructure and distribution of epidermal sensory receptors in the beak of the echidna, Tachyglossus aculeatus.

Within the rostral one centimetre of the Echidna beak, three specialised receptors were found: a mucous sensory gland, a rod-like structure, and an innervated epidermal pit. The mucous sensory gland consists of a dermal mucous gland and a modified epidermal portion. Bulbous nerve terminals, similar to those reported for the Platypus, were found within the modified epidermal portion of the mucous gland. The rod-like structure contains four types of nerve terminals: Merkel cells, Paciniform corpuscles, and a central and a peripheral vesicle chain receptor. Apart from minor differences, the rod-like structure is similar to that previously reported for the Platypus. Preliminary results are presented for a third structure: an innervated epidermal pit. Topographical and ultrastructural analyses are used in the context of functional interpretation.

Animals↗
PubMed1990

Extracutaneous viral inclusions in psittacine beak and feather disease.

Thirty-five birds that died with naturally acquired psittacine beak and feather disease (PBFD) were necropsied to identify extracutaneous viral inclusions. Inclusions were found in various tissue sections from 34 of 35 birds. By immunoperoxidase staining, intranuclear and intracytoplasmic inclusion bodies were shown to contain PBFD viral antigen. Inclusion-bearing lesions were widely disseminated but often closely associated with the alimentary tract. Lesions within the palate, esophagus, crop, intestine, bursa of Fabricius, and liver probably serve as sources for viral shedding into the feces.

Animals↗
PubMed1992

Production and characterization of monoclonal antibodies to psittacine beak and feather disease virus.

Monoclonal antibodies specific for the virus that causes psittacine beak and feather disease (PBFD) were produced by fusing spleen cells from mice immunized with purified concentrated PBFD virus with mouse myeloma cell line Sp2/0. The resulting hybridomas were tested for reactivity against whole purified virus by an enzyme-linked immunosorbent assay (ELISA) system. Four clones, designated 15H8, 8E3, 11G12, and 2C3, were subcloned by limiting dilution. Isotyping indicated that clone 15H8 was secreting IgG, whereas the remaining clones secreted IgM. The secreted immunoglobulins were characterized by reactivity against purified PBFD virus using immunoblotting procedures, by immunohistochemical staining of virus-induced lesions in infected tissues, and by inhibition of PBFD virus agglutination of cockatoo erythrocytes. Antibodies secreted by clones 15H8 and 8E3 had the strongest activity against purified whole virus. Only immunoglobulin secreted by the clone 15H8 could be used to detect viral antigen in infected tissues. None of the monoclonal antibodies had hemagglutination-inhibition activity.

Animals↗
PubMed1999

Electron microscopical observations of psittacine beak and feather disease in an Umbrella cockatoo (Cacatua alba).

Psittacine beak and feather disease (PBFD) was diagnosed in an umbrella cockatoo (Cacatua alba) with severe feather dystrophy and loss. Electron microscopically, the intranuclear and intracytoplasmic inclusion bodies observed by light microscopy were composed of viral particles forming paracrystalline arrays, whorls, semicircles or concentric circles. Recovered viral particles from the skin and feather follicle tracts were icosahedral and 15 to 20 nm in diameter.

Animals↗
PubMed1985

Electron microscope study of the Grandry and Herbst corpuscles in the palatine mucosa, gingival mucosa and beak skin of the duck.

Grandry and Herbst corpuscles of the palatine mucosa, gingival mucosa and beak skin were studied with the electron microscope. Typical Grandry corpuscles are surrounded by thick bundles of collagen fibers and composed of a terminal axon sandwiched between Grandry cells. Occasionally, two or three nerve endings are found within one corpuscle. The Grandry cell contains numerous electron-dense granules similar to those of a Merkel cell. The cell extends protrusions at the poles and the opposing faces. Desmosome-like attachments are noted between interdigitated protrusions, and between the axon and Grandry cell. Herbst corpuscles are composed of an outer capsule, inner core and central nerve ending. The outer capsule consists of 15 to 20 concentric lamellae, while the inner core possesses 60 to 70 sheets of cytoplasmic extensions. Under the scanning electron microscope, the corpuscles appeared as an elongated oval form surrounded by dense fibrous connective tissue, and each lamella of the outer capsule was composed of a dense network of thick and thin fibrils. These were seen under the transmission electron microscope as thick fibrils about 50 nm in diameter and peripheral thin fibrils about 10 nm in diameter. In some portions, a periodic increase of cytoplasmic density about 20 nm in width located in neighboring sheets was noted. The terminal axons of both corpuscles contain numerous neurofilaments, slender mitochondria, neurotubules, smooth endoplasmic reticulum and vesicles. Both corpuscles are limited by several flat cells which are arranged in parallel and probably correspond to the perineural cells of the peripheral nerve. Tight junctions were observed between these cells.

Animals↗
PubMed1991

Effect of beak-trimming age and high fiber grower diets on layer performance.

The performance of three commercial strains of White Leghorn layers was compared following beak trimming (BT) at 6 or 12 wk of age when fed diets containing 4.45 and 6.30% fiber between 6 and 12 or 12 and 18 wk of age, respectively. Body weights were lower at 12 wk in the 6-wk BT pullets, but were heavier at 18 wk when compared with the 12 wk BT pullets. Eighteen-week body weights were unaffected by feeding regimens. Six week BT resulted in higher hen-day and hen housed egg production, total egg mass, feed consumption, and total egg income. Profitability was superior for the 6-wk BT treatment (P = .072). Feeding the high fiber diets from 6 to 12 or 12 to 18 wk of age resulted in no differences in any of the adult performance traits measured compared with the control diet.

Animals↗
PubMed1992

Antibody response to and maternal immunity from an experimental psittacine beak and feather disease vaccine.

Adult umbrella cockatoos, Moluccan cockatoos, African grey parrots, and a yellow-headed Amazon parrot were inoculated IM or SC with beta-propiolactone-treated psittacine beak and feather disease (PBFD) virus. Thirty- to 45-day-old African grey parrot, umbrella cockatoo, and sulphur-crested cockatoo chicks also were vaccinated with the same inoculum. The hemagglutination inhibition (HI) and agar-gel diffusion tests were used to assay for post-vaccination development of anti-PBFD virus antibodies. All adult vaccinates seroconverted and had increases in HI and precipitating antibodies. The vaccinated chicks had increased concentrations of HI antibodies, but precipitating antibodies could not be detected. To demonstrate that chicks from vaccinated hens are protected from PBFD virus challenge, 3 African grey parrot chicks and 2 umbrella cockatoo chicks from vaccinated hens and 1 African grey parrot chick and 1 umbrella cockatoo chick from nonvaccinated hens were exposed to purified PBFD virus. Chicks from the vaccinated hens remained clinically normal during the 50-day test period. Chicks from the nonvaccinated hens developed clinical and histologic lesions of PBFD. Infected tissues from these birds were confirmed to contain viral antigen, using immunohistochemical staining techniques. The PBFD virus was recovered from the affected birds. These findings indicate that adult and 30- to 45-day-old psittacine birds will seroconvert following vaccination with beta-propiolactone-treated PBFD virus. Also, hens inoculated with beta-propiolactone-treated PBFD virus produce chicks that are, at least temporarily, resistant to virus challenge.

Animals↗
PubMed1991

Routes and prevalence of shedding of psittacine beak and feather disease virus.

Psittacine beak and feather disease (PBFD) virus was recovered from the feces and crop washings from various species of psittacine birds diagnosed with PBFD. High concentrations of the virus also could be demonstrated in feather dust collection from a room where 22 birds with active cases of PBFD were being housed. The virions recovered from the feces, crop, and feather dust were confirmed to be PBFD virus by ultrastructural, physical, or antigenic characteristics. Virus recovered from the feather dust and feces hemagglutinated cockatoo erythrocytes. The specificity of the agglutination was confirmed by hemagglutination inhibition, using rabbit antibodies against PBFD virus. During the test period, 26% (8 of 31) of the birds screened were found to be excreting PBFD virus in their feces, and 21% (3 of 14) of crop washings were positive for PBFD virus. Some birds in the sample group had active cases of diarrhea, whereas others had normal-appearing feces. Diarrhea was found to be the only significant indicator of whether a bird was likely to be excreting virus from the digestive tract. These findings suggest that exposure of susceptible birds to PBFD virus may occur from contact with contaminated feather dust, feces, or crop secretions. Viral particles that were morphologically similar to parvovirus (20- to 24 nm-icosahedral nonenveloped virions) also were recovered from feces of some of the birds.

Animals↗
PubMed1991

Hemagglutination by psittacine beak and feather disease virus and use of hemagglutination inhibition for detection of antibodies against the virus.

Conditions for psittacine beak and feather disease (PBFD) virus hemagglutination and hemagglutination-inhibition (HI) test reactions are defined. The PBFD virus was found to hemagglutinate cockatoo and some guinea pig erythrocytes. The HI test was used to assay serum antibody titer in birds with active PBFD virus infections and in others that had been exposed to diseased birds. On the basis of HI antibody titers in psittacine birds that had been exposed to PBFD virus, but remained clinically normal, we suggest that some birds exposed to the virus are able to mount an effective immune response. Birds with active PBFD virus infections had lower antibody values than did birds that had been exposed to the virus, but remained clinically normal. On the basis of these findings, the ability to develop a suitable HI antibody response may be crucial in determining the disease status of susceptible birds exposed to the PBFD virus. If HI antibodies are found to have neutralizing activity, then the fact that a high HI titer was induced in birds inoculated with purified PBFD virus might suggest that an immunization program would be effective in preventing PBFD virus infections.

Animals↗
PubMed1987

[Differentiation of tactile corpuscles (Merkel's) in the beak of Coturnix coturnix quail during ontogeny].

Succession of the Merkel's corpuscles appearance and the nervous fibers connected with them in the germ of the beak has been studied by means of light (silver nitrate impregnation) and electron microscopic techniques. Appearance of the Merkel's corpuscles in the subepithelial connective tissue is preceded by sprouting of nervous fibers into the area. From the very beginning of their differentiation the tactile corpuscles are in contact with nervous terminals. Sensory innervation is a necessary condition for differentiation of the Merkel's corpuscles and tactile bodies in the bird quail.

Animals↗
PubMed1986

Feather and beak dystrophy and necrosis in cockatoos: clinicopathologic evaluations.

Several species of imported and captive-bred southeast Asian cockatoos with feather and beak disease (FBD) were evaluated. In recently emerging stained feathers from affected birds, intracytoplasmic magenta to basophilic inclusions of various sizes were found in macrophages and basophil-like cells within the pulp and feather epidermis. Occasionally, amphophilic intranuclear inclusions were seen within degenerated feather epidermal cells. On the basis of electron microscopic findings, intracytoplasmic inclusions were not membrane bound and consisted of crystalline arrays of viral particles (17 to 22 nm in diameter). On the basis of size and conformation, viral particles most closely resembled those of parvovirus or picornavirus. Consistent hematologic or serum enzyme differences were not found among affected or healthy cockatoos. Compared with findings in healthy cockatoos, cockatoos with FBD had significantly lower serum protein concentrations, and results of serum protein electrophoresis indicated that birds with FBD had significantly lower concentrations of prealbumin and gamma-globulin fractions. Mean pre- and post-ACTH plasma corticosterone concentrations of cockatoos with FBD were not significantly different from those of healthy cockatoos. In 8 of 9 affected cockatoos evaluated, serum T4 concentrations before and after thyrotropin stimulation were considered normal.

Animals↗
PubMed1980

Ultrastructure of the Herbst corpuscle from beak skin of the pigeon.

In serial sections of the lamellar sensory Herbst corpuscle from beak skin of the domestic pigeon the authors followed the change in the ultrastructural picture in sections led at different levels of the corpuscle. In the proximal part of the corpuscle the inner core is formed by only a small number of broad lamellae whose number subsequently increases so that in the middle of the length there are much more lamellae and they are quite narrow. This situation is probably given by the fact that the lamellae of the inner core gradually "unwind" from the plasma of Schwann cells in distal direction. In order to judge the ultrastructure of sensory corpuscles it is necessary to have serial sections through the whole corpuscle or at least its greater part. In cross sections of the corpuscles it is visible that as a rule projections of Schwann cells reaching up to the axon are lying between the lamellar systems, forming in this way two interlamellar spaces. However, in some sections there are only collagen fibrils in one of the spaces. Ir reminds of the cleft in Pacinian corpuscles. The authors are therefore of the opinion that this phenomenon is caused by a proximodistal shift in the arrangement of Schwann cells of both sides in non-Lamellirostres. This space probably represents the boundary between the lamellar systems of neighbouring Schwann cells of one side. The study further confirmed the incidence of large dense core vesicles in the plasma and projections of Schwann cells. Their diameter ranges between 150...200 nm. The character of these vesciles, which also correspond to Merkel granules, may be explained by ultrahistochemical examination. Oblique sections through the lamellae of Schwann cells could imitate the incidence of sympathetic nerve fibres between the lamellae of th inner core or in neighbourhood of the axon, as stated by Santini. Finally, in one section at the very beginning of the corpuscle, the authors observed in close neighbourhood of the central axon a formation whose structure resembled a vegetative nerve fibre. However, its existence was not found in further sections. Evaluation will be possible only after gathering more material.

Animals↗
PubMed1993

Variation in clinical disease and species susceptibility to psittacine beak and feather disease in Zimbabwean lovebirds.

While psittacine beak and feather disease has caused 100% mortality in captive flocks of 2 species of native Zimbabwean lovebirds (Agapornis nigrigensis and A. lilianae), other lovebird species in close contact with the sick birds have been only transiently affected or not at all. The clinical course of the disease in affected lovebirds may differ from that reported elsewhere, with recovery in some cases. These differences, along with ultrastructural differences may suggest a different virus or different strain of virus underlying disease in Zimbabwe.

Animals↗