Beak Abnormalities Research Articles

Temporal Characterization of the Viral Load of Psittacine Beak and Feather Disease Virus in Rosy-Faced Lovebirds (Agapornis roseicollis)

Psittacine beak and feather disease virus (BFDV) is a widespread and highly pathogenic virus in parrots. The disease typically presents with feather and beak abnormalities, along with possible immune system suppression. No cure or commercialized vaccine is currently available. Our understanding of the Psittacine beak and feather disease often comes from infected individuals with visible symptoms. Limited knowledge exists regarding the pathology and role of asymptomatic individuals in disease transmission. Asymptomatic individuals could shed the virus in their crop secretion, feces, or feathers. In this study, we investigated the temporal change in the viral load in feather and fecal samples from 17 asymptomatic Rosy-faced Lovebirds (Agapornis roseicollis) using qPCR. Our results showed that most of the individuals had very low viral load, while three individuals with high viral load at the beginning of the experiment were observed to exhibit a decreasing trend in viral load in both fecal and feather samples. Surprisingly, the viral load in an individual can drop from a high level to an undetectable level within three months. This suggests that BFDV infection might not be lethal or highly pathogenic for some individuals. We also showed that the viral load in feathers was higher than in feces.

The impact of strain and cage type on the welfare of laying hens in different seasons

The aim of this study was to determine the effects of strain and cage type on the welfare of laying hens in commercial flocks over different seasons. A 2 x 2 x 3 factorial design was used to evaluate the effects of strain (white and brown layers) and cage type (conventional and enrichable battery cages) on the welfare of laying hens over three seasons (winter, spring and summer). The Welfare Quality® Assessment Protocol for Poultry was used to assess the welfare of laying hens. The strain and cage type significantly affected the welfare of the laying hens, which varied according to the season. Hens from the brown strain exhibited higher occurrences of FPD, keel bone abnormalities, and feather loss on the head and neck. White strains displayed a greater percentage of hens with abnormalities in the toe, comb, and beak, along with pecking wounds on the comb and extensive feather loss on the back, rump, and belly. A higher prevalence of comb abnormalities was observed in conventional cages. Hens in enrichable cages had higher rates of FPD, toe, comb and beak abnormalities, as well as pecking wounds on the comb and extensive feather loss. As a result, it was concluded that enrichable cages have a more adverse impact on the welfare of laying hens, with welfare losses in enrichable cages being more pronounced in brown hens compared to white hens and with interactions between strain and cage type varying seasonally.

Congenital abnormalities in dead-in-shell chicks associated with mixed bacterial infections

Determination of the chick embryonic developmental period at which embryonic mortalities occur could help in establishing the cause of such mortalities. The late stage of embryonic development has particular importance due to its dramatic effect on life after hatching. This study was conducted to investigate the occurrence, frequency and bacterial isolates from dead-in-shell chick embryos in Northern Jordan. A total of 1,000 unhatched eggs were collected at hatching day from 10 hatcheries located in Northern Jordan. Out of 1,000 eggs, 357 (35.7%) were fertile, of which 210 (58.8%) were dead-in-shell embryos. Approximately 50.5% of the dead embryos displayed abnormalities, including neck muscles with subcutaneous petechial haemorrhages (44.3%), beak abnormalities (3.8%), eye deformities (1.9%) and anencephaly (0.5%). Sixty-six bacterial isolates were identified from 82 samples from the dead-in-shell embryos. The isolates were 22 (33.3%) Escherichia coli, 18 (27.3%) Klebsiella pneumoniae, 14 (21.2%) Staphylococcus aureus, 5 (7.6%) Pseudomonas aeruginosa, 4 (6.1%) Salmonella enteritidis, 2 (3%) Bacillus cereus and 1 (1.5%) Proteus vulgaris. Mixed growth was also recorded in 16 (19.5%) samples. There was a significant (P < 0.05) association between Escherichia coli as a bacterial isolate and the occurrence of neck and beak abnormalities. In this study, infection of check embryos with several bacterial species, particularly Escherichia coli, was identified as an important cause of multiple congenital abnormalities involving the neck and beak of unhatched chicks.

Beak abnormality hinders provisioning ability and reduces body condition of a female House Wren (Troglodytes aedon)

Beak abnormalities have been reported in a wide range of species but typically affect only a small portion (<1%) of wild bird populations. Most research has focused on the prevalence, morphology, and causes of beak deformities, resulting in relatively little information on the consequences of these deformities for individual birds. Birds with abnormal beaks likely struggle to feed themselves, a situation that can only be exacerbated during the breeding season when they must provide food for not only themselves but also their offspring. We captured a female house wren (Troglodytes aedon) with abnormal mandibles during the 2016 breeding season. The female was lighter and smaller than normal, and her clutch size smaller and incubation and nestling periods slightly longer than normal. Using video recordings at the nest, we found that early in the nestling period the female's provisioning rate was lower and her time spent brooding greater than normal, yet she succeeded in rearing a smaller-than-average brood. We conclude that the female's abnormal beak was a severe handicap negatively affecting both her condition and her provisioning ability; however, it did not preclude her from raising a brood of nestlings.

Report on beak abnormalities of some birds of Patagonia

Report on beak abnormalities of some birds of Patagonia

Report on beak abnormalities of some birds of Patagonia

ABSTRACT Avian beaks are complex and highly specialized structures that if altered could hinder many aspects of bird biology. Here, we provide evidence from incidental sightings of 24 birds from 9 ...

Morphologically abnormal beaks observed in chickens that were beak-trimmed at young ages.

A survey of beak morphological abnormalities was performed on 6,201 chickens (egg-laying hens and chickens for meat production belonging to 25 flocks) brought to a poultry processing plant. The observed abnormalities varied among flocks with occurrence rates ranging from 0.48 to 46.67%. The occurrence was high in flocks subjected to beak trimming and varied significantly according to chicken breed, with the highest rates of abnormalities in a certain chicken breed. The most widely observed abnormalities were: 1) uneven growth of the upper and lower mandibles, mostly with elongation of the lower mandible (accounting for 64.8% of all abnormalities); 2) misalignment of the upper and lower mandibles, causing lateral deviation or crossing (16.3%); 3) sharp or jagged deformities of the mandible tips (10.1%); 4) permanent open beak, a deformity in which the beak did not close completely even when closed (5.8%); and 5) formation of tubercular swellings at the tips of the upper or lower mandibles (3.1%). This is the first report on the occurrence of beak abnormalities in beak-trimmed poultry in Japan.

External Beam Radiation Therapy of Squamous Cell Carcinoma in the Beak of an African Grey Parrot (Psittacus timneh)

Squamous cell carcinoma has been reported in a variety of bird species, most commonly psittacine and gallinaceous birds. The long-term prognosis in nongallinaceous birds is generally poor if complete surgical excision is not possible. Squamous cell carcinoma of the rhinotheca was diagnosed in a 34-year-old timneh African grey parrot (Psittacus timneh) with a 2-year history of beak abnormalities. No evidence of metastasis or local invasion were found on results of radiographs or computed tomography scan. The bird was treated with surgical debulking and palliative megavoltage radiation therapy. After 4 radiation treatments, the affected tissue was necrotic and was debrided to reveal healthy granulation tissue. The bird died approximately 7 months after diagnosis and 4 months after cessation of radiation treatment. At the time of death, a small scab lesion remained at the left oral commissure, but no visible tumor regrowth was evident. A postmortem examination was not performed, however, and tumor recurrence could not be ruled out in this bird.

Incidence, Severity, and Welfare Implications of Lesions Observed Postmortem in Laying Hens from Commercial Noncage Farms in California and Iowa.

The egg industry is moving away from the use of conventional cages to enriched cage and noncage laying hen housing systems because of animal welfare concerns. In this study, the prevalence and severity of lesions in noncage laying hens from commercial farms in two of the largest egg-producing states, California and Iowa, were evaluated by postmortem examination. Hens that died or were culled were collected during early, mid, and late stages of the laying cycle from 16 houses on three farms. Of the 25 gross lesions identified for study, 22 were observed, with an average of four lesions per hen. Vent cannibalism, reduced feather cover, keel bone deformation, and beak abnormalities were the most frequent lesions, observed in ≥40% of hens. Other common lesions were cloacal prolapse (30.5%), footpad dermatitis (24.3%), and septicemia (23.1%). Beak abnormality and enteric disease had the highest proportion of severe lesions. Pearson chi-square analysis revealed a number of stage-of-lay effects (P ≤ 0.05), some of which differed by state. For both states combined, the lesions observed more frequently during early lay were beak abnormalities, northern fowl mite infestation, and cage layer fatigue, whereas during mid lay, they were poor feather cover, vent cannibalism, footpad dermatitis, keel bone deformation, respiratory disease and roundworms. Feather pecking and cloacal prolapse were most common during late lay. Although differences in hen genetics, farm management practices, and environmental factors could all have affected the results of this study, the information provides a better understanding of hen health in noncage housing systems and could help to identify potential interventions to reduce hen welfare problems.

Environmental contaminants and chromosomal damage associated with beak deformities in a resident North American passerine.

A large cluster of beak abnormalities among black-capped chickadees (Poecile atricapillus) in Alaska raised concern about underlying environmental factors in this region. Metals and trace elements, organochlorine pesticides, polychlorinated biphenyls (PCBs), and polychlorinated dibenzo-dioxins and polychlorinated dibenzofurans (PCDD-Fs) were analyzed in adults, nestlings, and eggs of the affected population; local bird seed was also tested for organochlorine pesticides. The results offered no support for the hypothesis that selenium or any other inorganic element was responsible for beak deformities among chickadees, but some evidence that organochlorine compounds may be contributing factors. Adults with beak deformities had an elevated level of chromosomal damage, which was correlated with lipid level and concentrations of several organochlorine compounds. Multivariate analyses of pesticides and PCBs did not distinguish abnormal from normal adults, but subsequent univariate analysis demonstrated higher concentrations of heptachlor epoxide and PCB-123 in abnormal adults. Concentrations of all organochlorine compounds were low, and none is known to cause beak or keratin abnormalities. Patterns of PCB congener concentrations differed between nestlings with normal and abnormal parents. Eggs from clutches with low hatchability had higher concentrations of hexachlorobenzene and PCDD-Fs than those with high hatching success, and hexachlorobenzene was found in seeds. Additional testing for PCDD-Fs, polycyclic aromatic hydrocarbons, and other emerging contaminants, including brominated compounds, is needed to rule out environmental contaminants as a cause of beak deformities in chickadees in Alaska.

Macroscopic, Histologic, and Ultrastructural Lesions Associated With Avian Keratin Disorder in Black-Capped Chickadees (Poecile atricapillus)

An epizootic of beak abnormalities (avian keratin disorder) was recently detected among wild birds in Alaska. Here we describe the gross, histologic, and ultrastructural features of the disease in 30 affected adult black-capped chickadees (Poecile atricapillus). Grossly, there was elongation of the rhamphotheca, with varying degrees of lateral deviation, crossing, and gapping between the upper and lower beak. Not uncommonly, the claws were overgrown, and there was alopecia, scaling, and crusting of the skin. The most prominent histopathologic features in the beak included epidermal hyperplasia, hyperkeratosis, and core-like intrusions of necrotic debris. In affected birds, particularly those with moderate to severe beak overgrowth, there was remodeling of premaxillary and mandibular bones and various dermal lesions. Lesions analogous to those found in beaks were present in affected claws, indicating that this disorder may target both of these similar tissues. Mild to moderate hyperkeratosis occurred in other keratinized tissues, including skin, feather follicles, and, occasionally, sinus epithelium, but typically only in the presence of microbes. We did not find consistent evidence of a bacterial, fungal, or viral etiology for the beak lesions. The changes observed in affected birds did not correspond with any known avian diseases, suggesting a potentially novel hyperkeratotic disorder in wild birds.

On-farm survey of beak characteristics in White Leghorns as a result of hot blade trimming or infrared beak treatment

SUMMARY Commercial laying hens in North America are typically beak trimmed to prevent injury and mortality caused by feather pecking and cannibalism. Beak trimming is most commonly performed on day-old chicks at the hatchery, either by hot blade (HB) or infrared (INF) techniques. The differences between these 2 methods and the potential variability within each method may cause morphological differences in the beaks of laying hens throughout their production cycle. Few data are available detailing variations between the beaks of laying hens after trimming in commercial settings. The purpose of this field survey was to measure beak lengths of 4 commercial laying hen flocks at 2 age ranges treated by either HB or INF techniques at hatch. Statistical analyses of the data for the 2 treatment types were not possible because of genetic and environmental differences between flocks; therefore, statements comparing treatments are not meant as definitive and are provided for general information only. Infrared-treated hens had shorter beaks with a lower SEM, and they generally exhibited fewer beak abnormalities than HB-trimmed hens at both ages. It is our observation in this field survey that INF-treated commercial hens seemed to have less variation in beak length and fewer beak abnormalities.

Epizootic of Beak Deformities Among Wild Birds in Alaska: An Emerging Disease in North America?

ABSTRACT. The sudden appearance of a large cluster of animals with gross abnormalities may signal a significant change in an ecosystem. We describe an unusual concentration of beak deformities that appear to have arisen rapidly within Alaska and now extend southward along the Pacific Coast. In Alaska we have documented 2,160 Black-capped Chickadees (Poecile atricapillus) and 435 individuals of 29 other species of birds, primarily during the past decade, with grossly overgrown and often crossed beaks. The annual prevalence of beak abnormalities among adult Black-capped Chickadees in south-central Alaska varied from 3.6% to 9.7% and averaged 6.5 ± 0.5% between 1999 and 2008. Only 0.05 ± 0.05% of nestlings and 0.3 ± 0.2% of juveniles <6 months old had abnormal beaks, which suggests that this is either a latent developmental or an acquired condition. We documented 80 cases in which a Black-capped Chickadee captured with an apparently normal beak was subsequently recaptured with a beak abnormality and 8 cases ...

Beak Deformities in Northwestern Crows: Evidence of a Multispecies Epizootic

ABSTRACT. Beak abnormalities are rare among adult birds and, typically, are not widespread in a given population, within a region, or across multiple species. A high concentration of beak deformities was recently documented in Black-capped Chickadees (Poecile atricapillus) and other resident avian species in Alaska. We describe a parallel condition in Northwestern Crows (Corvus caurinus) that signals the emergence of a multispecies epizootic. On the basis of 186 Northwestern Crows captured at six sites in Alaska during 2007 and 2008, we estimated the prevalence of beak deformities in adults to be 16.9 ± 5.3%, the highest rate of gross deformities ever recorded in a wild bird population. Prevalence varied among sites and was as high as 36% on the Kenai Peninsula, which suggests possible epizootic clusters. We also documented beak abnormalities in an additional 148 Northwestern Crows in south-central and southeastern Alaska and in 64 crows near Vancouver, British Columbia, and Puget Sound, Washington, a reg...

Severe Leukopenia and Liver Necrosis in Young African Grey Parrots (Psittacus erithacus erithacus) Infected with Psittacine Circovirus

This paper describes the signs, clinical pathology, and postmortem findings in 14 young African grey parrots (Psittacus erithacus erithacus) that were naturally infected with psittacine beak and feather disease (PBFD) virus (psittacine circovirus). All but two of the parrots had severe leukopenia at clinical presentation. Two other parrots also had severe anemia. All birds died within 3 wk after presentation. Postmortem examination documented liver necrosis in 11 of 14 birds and secondary bacterial or fungal infections in 9 of 14 birds. Tests for Chlamydia psittaci, polyomavirus, and Salmonella sp. were negative. PBFD viral infection could be demonstrated in all birds by polymerase chain reaction. Supporting evidence of PBFD viral infection was gathered by histologic examination of the bursa of Fabricius, electron microscopy, and DNA in situ hybridization. Electron microscopic examination of both the bursa of Fabricius and liver revealed virus particles resembling circovirus. DNA in situ hybridization of six liver tissue samples confirmed the presence of PBFD virus and excluded the presence of avian polyomavirus. Our findings suggest that a specific presentation of peracute PBFD viral infection, characterized by severe leukopenia, anemia, or pancytopenia and liver necrosis in the absence of feather and beak abnormalities, may occur in young African grey parrots.

Cytology of recessive sexual-phase mutants from wild strains of Neurospora crassa.

Wild-collected strains of Neurospora crassa harbor recessive mutations that are expressed in the sexual phase when homozygous. Thirty-two representative mutants that produced barren perithecia were examined cytologically. Six of these mutants failed to form asci. Of the remaining 26, chromosome pairing was disturbed in 12 and meiosis was disturbed at pachytene or diplotene in 5. Seven mutants showed normal meiosis I but then diverged from the normal sequence, and two showed perithecial beak abnormalities. In many mutants, ascus development and nuclear divisions continued after the initial defect, albeit abnormally. Nuclear divisions were often delayed, essentially uncoupling them from other ascus events such as the formation of enlarged spindle pole body plaques, ascospore wall membranes, and spore delimitation. All 32 mutants were recessive and none showed obvious morphological abnormalities during vegetative growth. This phenotype contrasts sharply with that of numerous laboratory-induced ascus mutants, which are frequently expressed pleiotropically in the vegetative phase and several are dominant in the sexual phase.

Teratogenic activity of aliphatic and aromatic fractions of Prudhoe Bay crude and fuel oil No. 2 in the chicken embryo

The teratogenic and embryotoxic activities of aliphatic (fraction 1), two- or three-ring aromatic (fraction 3), and four- or five-ring aromatic (fraction 4) fractions of Prudhoe Bay crude oil and fuel oil No. 2 were investigated in the developing chicken embryo. Embryos were treated at 96 hr development via the air sac membrane. Treatment with the aliphatic fraction of either oil did not cause any increase in developmental abnormalities; however, it did result in a dose-related significant decrease in weight, crown-rump length, and head length. Fraction 3 of both oils had both teratogenic and embryotoxic activities in the embryos, causing aberrations such as gastroschisis, edema, beak abnormalities, hemorrhages, and limb defects. Fraction 4 of Prudhoe Bay crude caused a slight but insignificant increase in developmental abnormalities while fraction 4 of fuel oil No. 2 had no teratogenic effect at the concentrations tested.

Congenital abnormalities in methylmercury poisoning

This study was undertaken to determine the teratogenic potential of methylmercury on chick embryogenesis. Methylmercuric chloride was dissolved in sodium bicarbonate (.2%) and administered to the chick embryos at doses ranging from .0009 to .010 mg per egg. The injections were made at days 2 and 3 of incubation (Groups A and B). All the embryos including controls were examined on the 7th day of incubation. Methylmercury poisoning was observed to be both embryolethal and teratogenic. Within the two groups, embryolethality was higher in Group A. The following congenital abnormalities were observed: exencephaly, shortened and twisted limbs, microphthalmia, shortened and twisted neck, beak abnormalities, everted viscera, reduced body size and hemorrhage all over the body. Exencephaly and limb abnormalities were very common. No differences in the incidence and types of gross abnormalities within both the groups (A and B) were noted. The incidence of malformations among the controls was low. The results of present investigation show that methylmercury poisoning is both embryolethal and teratogenic to early chick embryogenesis.

Studies on Synergism in Combinations of Anti-Tumour Agents in Chick Embryos.

Experiments have been carried out in which the effects of hydroxyurea alone and 5-BUdR alone, as well as in combination, on the development of chicken embryos were studied. The results were as follows: 1. Pilot experiments showed that neither hydroxyurea (0.05 mg/egg) or BUdR (0.025 mg/ egg) alone produced abnormalities during development. 2. When hydroxyurea was administered at 24 hours incubation and 5-BUdR 6 hours later, mortality was high. Mortality decreased as the interval between the two treatments was lengthened to 12 hours and 24 hours. 3. The incidence of beak abnormalities and micromelia rose when hydroxyurea treatment was followed by 5-BUdR by 6 hours or 12 hours. The incidence and severity of the defects declined as the interval was increased to 24 hours. 4. Whether 5-BUdR was injected first followed by hydroxyurea or hydroxyurea was followed by 5-BUdR, when the interval between the initial and the second injection was 6 or 12 hours, the toxic effects and the typical symptoms observed in the embryos were similar. 5. When the time interval between the injection of 5-BUdR followed by hydroxyurea was 24 hours, the mortality as well as incidence of typical abnormalities were reduced considerably. 6. It is supposed that the absence of any remarkable morphological defects when embryos were treated either with hydroxyurea or BUdR alone might be due to a repair mechanism in the DNA of the cells. The pronounced synergistic effects of combination of hydroxyurea and 5-BUdR reported here, could be due to the blockade of thede-novo biosynthesis of DNA.

Problems of acetazolamide and N‐ethylnicotinamide as teratogens

AbstractExperiments with acetazolamide and N‐ethylnicotinamide were made by injection into the yolk sac of chicken eggs after 24 and 96 hours of incubation. Acetazolamide produced in both stages abnormalities of the upper beak, the dosage‐effect response following a linear course. Effects minor in incidence were rumplessness at 24 hours, bending of tibiotarsus shaft in both stages and muscular hypoplasia after 96 hours. N‐ethylnicotinamide led to abnormalities of the upper beak in both stages. to malformations of tibiotarsus and fibula at 96 hours. With increasing dosages the results of N‐ethylnicotinamide rose by threshold effects. In a particular strain of White Leghorn fowl embryos gave little or no response to acetazolamide; N‐ethylnicotinamide produced the usual incidence of long bone defects, but few beak abnormalities. Acetazolamide acted as protective supplement when added to treatment with sulfanilamide; it prevented all abnormalities (micromelia) of long bones; it reduced incidence of defects of upper and lower beak after treatment at 24 hours, but not those of upper beak after 96 hours. N‐ethylnicotinamide also gave complete protection against sulfanilamide‐induced abnormality of lower beak and long bones, but an increased incidence of shortened upper beak. Acetazolamide and N‐ethylnicotinamide injected together at 96 hours led to exaggeration in incidence and change in expressivity of defects of the upper beak and a drastic lowering in frequency of tibiotarsus‐fibula malformations. Supplements of ADP reduced toxicity of acetazolamide and incidence of defects of the upper beak produced by it. Interference with NAD functions and oxidative phosphorylation is likely to be the cause of the teratogenic effects of acetazolamide as well as N‐ethylnicotinamide.