Necropsied Birds Research Articles

Microbiology, induction, and management practices to mitigate lameness caused by bacterial chondronecrosis with osteomyelitis in broiler chickens

Bacterial chondronecrosis with osteomyelitis (BCO) lameness is the most prevalent skeletal disorder in poultry, implicated by the inherent risk of the high growth rate of modern broilers. The non-synchronization of massive body mass accretion vs maturation of the structural bone induces vulnerability to bone microfracture and immunosuppression, leading to bacterial necrosis in the skeletal and thoracic vertebral bones, leg paralysis, and eventual death. BCO lameness also imposes animal welfare issues and confers food safety risks. A study in 20 broiler farms in Australia recorded 28% BCO lesions of the necropsied birds, while a study in commercial flocks in Europe reported 19% moderate-to-severe lameness symptoms. The high incidence of lameness in commercial broiler farms reduces production value and leads to a huge economic loss in the poultry industry. Managing BCO lameness in broiler poultry is more challenging than that of other species because the peak of lameness incidence emerges at the marketing age of broilers. Moreover, curative treatment of the affected broilers is arduous due to their larger populations but shorter production cycles. Thus, condemnation of clinically lame birds has been a common practice in broiler farms to prevent the transmission of highly contagious BCO throughout the broiler populations. This practice decreases the production value and increases the economic forfeits. Therefore, presenting intervention measures for managing and controlling BCO in broiler poultry is necessary. Knowledge of etiological agents, pathogenesis, detection, and experimental lameness models to evaluate the efficacy of the intervention measures is highly important in presenting approaches to mitigate BCO lameness. Thus, this review focuses on microbiology studies of BCO, models of creating experimental lameness, and intervention measures mitigating BCO lameness in broiler chickens.

Molecular and Pathological Investigation of Infectious Bronchitis in Broiler Flocks in Sulaimani Province, Iraq

This research's goal was to examine the molecular analysis and pathological lesions linked to IBV infection in flocks of naturally infected broiler chickens from non-vaccinated and vaccinated (H120, MA5+IB 4-91) flocks. One hundred sixteen birds were collected in Sulaimani provinces between November 2021 and July 2022 from various broiler chicken flocks of vaccinated (H120, MA5+IB 4-91) and non-vaccinated birds who suffered from respiratory illness. Viral isolation and PCR were used to confirm the infection. The majority of the necropsied birds showed congested trachea and the presence of mucus with caseated debris at the bifurcation. There was a white precipitate in the ureters, also the kidneys were enlarged and congested. Sequencing of the S1 glycoprotein gene revealed that four isolates found and after phylogenetic analysis of the strains' deduced amino acid sequences indicated that they had a close relationship with the Iranian strains MG013972 and MG013973 as well as the Iraqi strain MH747093. The non-vaccinated chickens' histopathological evaluation of all organs was more severe than that of the vaccinated chicks, with catarrhal exudate obstructing the tracheal lumen and tracheal epithelium undergoing hyperplasia to squamous metaplasia. In lung sections, catarrhal exudate partially to completely blocked the parabronchial lumen and the intrabronchial septa thickened due to alveolar capillary congestion, and an inflammatory reaction. Mild to severe glomerulonephritis with considerable collecting epithelial cell degeneration was seen in the kidney segment. Finally, it can be said that the infectious bronchitis virus is a significant contributor to the respiratory and/or renal issues affecting the flocks of broiler chickens in Sulaimani Province.

Salmonella Pullorum in a Free-range Chicken Farm in Western Bahia, Brazil

Background:Industrial poultry farming has developed progressively in Brazil, conferring the country a prominent position on the national and international scene. Likewise, alternative poultry farming is an important economic activity for small-scale family farmers. However, shortcomings related to sanitary management lead to increased occurrence of avian diseases, such as those caused by Salmonella spp. Despite salmonellosis has been described in industrial establishments, reports in alternative farms are less common, therefore the objective of this study was to describe the occurrence of salmonellosis in free-range chickens in the municipality of Barra, Western Bahia, Brazil. Cases: The poultry farmer reported the occurrence of diarrhoea in his chicken flock since the acquisition of the batch of chicks. Initially, carrying out the medicinal treatment of the birds, there was clinical improvement, however, successive recurrences of clinical signs occurred, such as diarrhoea, apathy, anorexia, and death of some birds. Upon learning about the case, an epidemiological investigation of the flock was carried out, and it was noted that some of the birds were retracted, apathetic, anorexic, and a lot of diarrheic faeces of a yellowish-white appearance were also observed. The entire flock had a history of vaccination against diseases: newcastle disease, infectious bronchitis, gumboro disease, and fowlpox. For better evaluation, five birds were necropsied, enabling the observation that the animals had a good body score. However, the necropsy revealed lesions such as splenomegaly, hepatomegaly, and enteritis in the three birds initially analysed (Animals 1, 2, and 3). The other birds (Animals 4 and 5) were submitted to evaluation for Eimeria sp. oocysts by means of scrapings from the intestinal mucosa, and there were no structures compatible with oocysts. Faecal samples were collected from another six birds in the flock for coproparasitological examination, and the presence of oocysts was not detected. Finally, sera from 20 birds in the flock were collected for the Rapid Serum Agglutination Test (SAR) for the detection anti-Salmonella Pullorum antibodies. Discussion: The diagnosis was based on clinical evaluation, post-mortem pathological findings of the necropsied birds, epidemiological data and confirmed with SAR testing, whereby 11 birds were seropositive for Salmonella enterica subspecies enterica serovar Pullorum. The prevalence of S. Pullorum is poorly described in alternative farming. Based on the farmer's report, it is believed that the chicks were purchased already infected, because birds from the same batch, also purchased by neighbouring producers, showed the same clinical signs. The unsatisfactory sanitation in the flock was another factor that may have favoured the persistence of the bacteria, since, the lack of removal of organic matter is a source of nutrients for microorganisms, and this may have favoured the multiplication and maintenance of the bacteria in the down feathers, feed, and water. The elimination of S. Pullorum through the faeces, in addition to the density of the birds, may have led to transmission to the other healthy birds. However, the knowledge and adoption of prophylactic measures in free-range chicken farms is a crucial factor in minimizing the occurrence of outbreaks and thus avoiding a future public Health Problem. Keywords: poultry pathology, alternative poultry farming, salmonellosis. Título: Samonella Pullorum em criação de galinhas caipiras no Oeste da Bahia, Brasil Descritores: patologia aviária, avicultura alternativa, salmoneloses.

Effects of early feeding of enzymatically treated yeast on growth performance, organ weights, intestinal histomorphology, and ceca microbial metabolites in broiler chickens subjected to Eimeria challenge

The study evaluated effects of early feeding of enzymatically treated yeast on growth performance and selected physiological responses in broiler chickens. A total of 480-day-old (male) Ross × Ross 708 broiler chicks were placed in 24 floor pens (20 birds per pen) and allocated to 2 diets (control vs. yeast) in a completely randomized block design (n = 12). Diets were formulated for a 5-phase feeding program: Pre-starter; d 0 to 6 Starter; d 7 to 15, Grower: d 16 to 28, Finisher 1; d 28 to 42 and Finisher 2; d 43 to 56. The yeast was applied in pre-starter and starter diets at 0.6 and 0.2%, respectively. Birds received a common diet from d 16 to 56. Feed intake (FI) and body weight (BW) were recorded by phase for calculation of BW gain (BWG) and FCR. On d 10, all birds received an oral dose of 25,000 E. acervullina and 5,000 E. maxima sporulated oocysts in 1 mL of sterile saline. On d 15 post-hatch, one bird per pen was sacrificed for organ weights (gizzard, small intestine, ceca, liver, spleen, liver, and bursa), jejunal tissues for histomorphology and ceca digesta for microbial activity. On d 56, one bird per pen was sacrificed for organs and breast weight. In pre-starter phase, yeast fed birds showed improved (P < 0.05) BWG and FCR than control fed birds. Combining pre-starter and starter phases, the FCR of yeast fed birds showed improved FCR (1.115 vs. 1.135; P < 0.05) than control. The overall BWG (d 0–56) was 3.920 and 3.962 kg/ bird and corresponding values for FCR were, 1.808 and 1.755, for the control and yeast, respectively. Diets had no (P > 0.05) effects on physiological responses evaluated on necropsied birds except that yeast birds had (P < 0.05) lighter bursa than control birds on d 15. The current data indicated that yeast could support growth in early life of broiler chickens, but these effects were not sustained after the transitioning birds to common grower and finisher diets.

Plastics in regurgitated Flesh-footed Shearwater (Ardenna carneipes) boluses as a monitoring tool

Plastic production and pollution of the environment with plastic items is rising rapidly and outpacing current mitigation measures. Success of mitigation actions can only be determined if progress can be measured reliably through incorporation of specific, measurable targets. Here we evaluate temporal changes in the amount and composition of plastic in boluses from Flesh-footed Shearwaters during 2002–2020 and assess their suitability for measuring progress against national and international commitments to reduce plastic pollution. Plastic in the shearwater boluses showed a generally decreasing pattern from 2002 to 2015 and increasing again to 2020. The colour and type of plastics in boluses was comparable to items recovered from live and necropsied birds, but a much smaller sample size (~35 boluses/year) was required to detect changes in plastic number and mass over time. We therefore suggest shearwater boluses are a low-effort, high-statistical power monitoring tool for quantifying progress against environmental policies in Australia.

Treatment with chloroquine is retinotoxic in captive African penguins (Speniscus demersus). Attenuation and recovery of electroretinographic responses.

To evaluate the effect of prophylactic anti-malarial chloroquine treatment, and its cessation, on electroretinographic (ERG) responses of captive African penguins. A brief ERG protocol ("QuickRetCheck") was recorded under mesopic conditions with manual restraint and no sedation or pupil dilation. Birds were recorded on two separate occasions, first while being treated with a daily chloroquine dose of 10mg/kg for 12days (n=15, treatment group) and second after 4months without chloroquine treatment (n=6, off-treatment group). Three birds were recorded on both occasions. Three other birds from the flock that died were studied histopathologically. Scotopic responses were unmeasurable in either recording and therefore were not analyzed. Mean a- and b-wave amplitudes of the mixed rod-cone responses to standard (3cd·s/m2 ) and high (10cd·s/m2 ) intensity flashes were higher in the off-treatment group. No difference in implicit times was observed. Sex, age, and number of previous chloroquine treatments did not affect ERG responses. Histopathology revealed Plasmodium spp.in the lungs, liver, and brain, but not in the eyes, of the necropsied birds, and there were no signs of retinitis or retinopathy. Daily chloroquine treatment was associated with attenuated ERG responses in penguins, which improve following cessation of treatment. Further work is warranted to establish a chloroquine dose that is efficacious yet has minimal adverse effects. Our results suggest that ERG responses of captive penguins undergoing ERG for any indication (such as prior to cataract surgery), must be evaluated in light of the birds' anti-malaria treatment status.

Mortality among free-ranging California condors (Gymnogyps californianus) during 2010–2014 with determination of last meal and toxicant exposure

Over the past 30 years, the California condor (Gymnogyps californianus) population has rebounded from 22 individuals to over 200 birds living in the wild. Historical impacts to the population have been largely anthropogenic. In this study, we explore mortality and cause of death data from condors that died during the years 2010-2014 and compare these to mortality data described by Rideout et al. in 2012, covering the years 1992-2009. In addition, morphologic and genetic analysis of the contents of the upper gastrointestinal (GI) tract was performed on the 2010-2014 condor mortalities to determine animal origins of the last meal eaten. The maximum population at risk within this time frame was 329 birds. During this time, 88 condors died and underwent post-mortem examination, and 41 birds were lost to tracking efforts and presumed dead (crude mortality rate of 39%; 129/329). A cause of death was determined for 66 of the 88 necropsied birds. Lead toxicosis remained a significant negative factor in condor population recovery, being related to the deaths of 37 adult and juvenile condors (proportional mortality rate 56%). Compared to condors succumbing to other causes of death, cattle were less often part of the last meal of lead-intoxicated condors. Based on these data, continued efforts to mitigate the impact of lead on California condors should be pursued.

Getting under the birds' skin: tissue tropism of Borrelia burgdorferi s.l. in naturally and experimentally infected avian hosts.

Wild birds are frequently exposed to the zoonotic tick-borne bacteria Borrelia burgdorferi sensu lato (s.l.), and some bird species act as reservoirs for some Borrelia genospecies. Studying the tropism of Borrelia in the host, how it is sequestered in different organs, and whether it is maintained in circulation and/or in the host's skin is important to understand pathogenicity, infectivity to vector ticks and reservoir competency.We evaluated tissue dissemination of Borrelia in blackbirds (Turdus merula) and great tits (Parus major), naturally and experimentally infected with Borrelia genospecies from enzootic foci. We collected both minimally invasive biological samples (feathers, skin biopsies and blood) and skin, joint, brain and visceral tissues from necropsied birds. Infectiousness of the host was evaluated through xenodiagnoses and infection rates in fed and moulted ticks. Skin biopsies were the most reliable method for assessing avian hosts' Borrelia infectiousness, which was supported by the agreement of infection status results obtained from the analysis of chin and lore skin samples from necropsied birds and of their xenodiagnostic ticks, including a significant correlation between the estimated concentration of Borrelia genome copies in the skin and the Borrelia infection rate in the xenodiagnostic ticks. This confirms a dermatropism of Borrelia garinii, B. valaisiana and B. turdi in its avian hosts. However, time elapsed from exposure to Borrelia and interaction between host species and Borrelia genospecies may affect the reliability of skin biopsies. The blood was not useful to assess infectiousness of birds, even during the period of expected maximum spirochetaemia. From the tissues sampled (foot joint, liver, spleen, heart, kidney, gut and brain), Borrelia was detected only in the gut, which could be related with infection mode, genospecies competition, genospecies-specific seasonality and/or excretion processes.

Evaluation of transmission potential and pathobiological characteristics of mallard originated Avian orthoavulavirus 1 (sub-genotype VII.2) in commercial broilers

Newcastle disease (ND), caused by Avian orthoavulavirus 1 (AOAV-1), affects multiple avian species around the globe. Frequent disease outbreaks are not uncommon even in vaccinates despite routine vaccination and, in this regards, viruses of diverse genotypes originating from natural reservoirs (migratory waterfowls) play an important role in a disease endemic setting. Though genomic characterization of waterfowl originated viruses has been well-elucidated previously, there is a paucity of data on clinico-pathological assessment of mallard-originated sub-genotype VII.2 in commercial chickens. Hence, the current study was designed to evaluate its transmission potential, tissue tropism and micro- and macroscopic lesions in commercial broilers. Based on complete genome and complete F gene, phylogenetic analysis clustered the study isolate within genotype VII and sub-genotype VII.2 in close association with those reported previously from multiple avian species worldwide. The study strain was found to be velogenic on the basis of typical residue pattern in the F-protein cleavage site (112R-RQ-K-R↓F117), sever disease induction in chicken, tissue tropism and subsequent clinico-pathological characteristics. Giving a clear evidence of horizontal transmission, a 100% mortality was observed by 4th and 6th day post infection (dpi) in chickens challenged with the virus and those kept with the challenged birds (contact birds), respectively. The observed clinical signs, particularly the greenish diarrhea, and macroscopic lesions such as pinpoint hemorrhages in proventriculus and caecal tonsils were typical of the infection caused by an AOAV-1 in chickens. The virus exhibited a broad tissue tropism where genomic RNA corresponding to study virus was detected in all of the tissues collected from recently mortile and necropsied birds. The study concludes that mallard-originated Avian orthoavulavirus 1 is highly velogenic to commercial chicken and therefore ascertain continuous disease monitoring and surveillance of migratory/aquatic fowls to better elucidate infection epidemiology and subsequent potential impacts on commercial poultry.

Gastrointestinal helminths of Humboldt penguin (Spheniscus humboldti Meyen, 1834) from south central Chile

The study of parasitism in penguins is relevant because it offers information on the biology and ecology of this host. This study reports the parasitism of 156 specimens of Spheniscus humboldti rescued from beaches of the south-central coast of Chile, between January 2006 and June 2015, describing their potential forms of transmission and pathogenicity. The parasitic infection was determined by coproparasitic methods in live specimens and by necropsy in dead penguins. The gastrointestinal helminths Tetrabothrius eudyptidis (Lonnberg, 1896), Cardiocephaloides physalis (Lutz, 1926), Contracaecum pelagicum (Johnston & Mawson, 1942) and Cosmocephalus obvelatus (Creplin, 1825) were identified by both methods. Parasitism was observed in 29.57% of live specimens and 51.76% of necropsied birds. All the parasites identified corresponded to genera already informed in S. humboldti . The richness of the S. humboldti parasitic fauna was lower than that reported for other species of penguins. The results demonstrate the participation of S. humboldti as a definitive host in the life cycles of the parasites reported in this study. Being S. humboldti a vulnerable species, it is necessary to continue with parasitological studies in this penguin to clarify the role of parasites in the health of these birds.

Occurrence and antimicrobial susceptibility of Salmonella spp. isolated from domestic pigeons Columba livia var. domestica in 2007-2017 in Poland

Salmonellosis is one of the most important bacterial diseases in pigeons. The disease occurs in birds of different ages, and long-term Salmonella spp. carrier status is a major problem. The study included 499 samples from live pigeons and internal organs from 265 necropsied birds. The samples were cultured on a standard and selective media. Their antimicrobial susceptibility was carried out by the Kirby-Bauer diffusion method. Thirty one Salmonella spp. isolates were cultured. Most isolates were obtained from the internal organs of dead or euthanised pigeons, and only single isolates were obtained from droppings and cloacal swabs. A total of 4% of the samples tested were positive. The greatest percentage of isolates was susceptible to enrofloxacin (96.3%) and florfenicol (95.7%). Sulfamethoxazole and trimethoprim combination was effective against 73.9% of the isolates. Despite the fact of increasing antibiotic resistance of the investigated bacteria, it is comforting that enrofloxacin remains highly effective despite its widespread use in birds.

Microbiological diagnosis and antimicrobial sensitivity profiles in diseased free-living raptors

ABSTRACTFree-living raptors (birds of prey) can act as reservoirs of potentially zoonotic agents, but they also can be affected by microorganisms as target hosts. In this retrospective study, microbiological results (n = 663) and antibiotic sensitivity profiles (n = 108) of bacterial isolates were analysed from diseased free-living raptors. Sixty-nine percent of cases (n = 457) yielded bacteria: 58% were in pure culture and 42% were of different species. Remarkably, samples from necropsies (47%) had higher percentage of pure isolations than those obtained from clinical (31%) samples (P < 0.001). Among bacterial isolates, Escherichia coli was the most common agent (35%), principally recovered from necropsied birds with clinical signs of septicaemia or respiratory disorders. Pseudomonas aeruginosa (7%) was isolated from birds with systemic infection and from oral lesions, especially in nocturnal raptors (P < 0.001). Staphylococcus spp. (5%), mainly Staphylococcus aureus, was found to be the most prevalent cause of pododermatitis (35%) and Staphylococcus hyicus was isolated from conjunctivitis (18.2%). Interestingly, 8% of samples with lesions compatible with avian tuberculosis were positive to the Mycobacterium avium complex. The most frequent fungi associated with pneumonic lesions and ingluvitis were Aspergillus spp. and Candida spp., respectively. More than 50% of the 108 isolates (34 different bacterial spp.) demonstrated resistance to clindamycin, ampicillin, tetracycline, cefuroxime, enrofloxacin and trimethoprim/sulphamethoxazole. Among the E. coli strains, 71% (27/38) presented a multidrug-resistance pattern to >3 antimicrobials. Detection in wildlife of antimicrobial-resistant pathogens that might be significant at the animal–human–ecosystem interface is of great relevance under the ‘One Health’ approach.

Pathologic and microbiologic aspects of pet psittacine infected by Escherichia coli and Salmonella Typhimurium

ABSTRACT: The role of Escherichia coli in healthy microbiota of psittacine is controversial, and the presence of Salmonella sp. indicates possible disease. Therefore, this study aimed to identify the presence of E. coli and Salmonella spp. in a psittacine pet that died in Fortaleza, Brazil, correlating pathogenicity aspects of the isolates through the evaluation of lesions and antimicrobial susceptibility. Psittacine pets sent to the Laboratory of Ornithological Studies, State University of Ceará, that died in 2014 and 2015 were necropsied. Fragments of liver, kidneys, intestine, lung, heart, spleen and brain were collected for microbiological and histopathological analyses. Scores were attributed to lesions and isolated strains submitted to antimicrobial susceptibility test. From the seventy necropsied birds, nineteen were positive for E. coli and one for Salmonella Typhimurium. Congestive lesions and lymphoplasmocitic inflammatory infiltrate were observed varying from light to moderate and were the main findings. In the analyzed strains, multidrug resistance against different groups of antibiotics was observed. In conclusion, according to the results, E. coli strains and the Salmonella Typhimurium isolate produced significant lesions in the psittacine pets, and multidrug resistance may hinder treatments with antibiotics used in avian pet medicine.

Pathological Studies on Infectious Bronchitis Disease in Chickens

Infectious bronchitis virus has been recognized as highly contagious disease in chickens. In this study, 138 birds from 10 broiler chicken flocks that suffered from respiratory disease were examined to study the pathological lesions associated with IBV infection in naturally infected flocks. Moreover, the infection was confirmed via virus isolation and PCR. Samples were harvested from both Sharkia and Gharbia provinces during one year. The clinical examination of the investigated birds showed nasal discharges, gasping and rales. Congested trachea with lumen contained mucus and caseated material at the biforcation of the two main bronchi were characteristic in most of the necropsied birds. The kidneys were enlarged and dark red or pale with the presence of whitish precipitate in the ureters. Four isolates recovered from four different broilers chicken’s flocks were further analyzed by S1 glycoprotein gene sequencing. The phylogenetic analysis of the deduced amino acids sequences of the four strains revealed that they were closely related to the IBV Egyptian variant 2 and IS/1494/2006 strains. The histopathological examination of the kidneys showed focal aggregation of lymphocytes in the renal cortex and the medulla. The liver showed multiple focal areas of necrosis which replaced by lymphocyte and heterophils aggregation. The spleen showed thickened capsule with subcapsular hemorrhage and mild to severe focal depletion of lymphocytes. Trachea, lung, proventriculus, intestine and bursa showed hyperplasia and degenerative changes in their epithelium. Blood vessels showed endotheliosis with perivascular edema and leukocyte infiltration in various organs. Edema was also seen in heart, trachea and lungs. Finally, it could be concluded that infectious bronchitis virus is a major cause and strongly implicated in respiratory and/or renal problems of the Egyptian broiler chicken flocks. Moreover, Egyptian variant 2 still evolving and causing severe damage to renal tissue and various organs.

English

A potency trial was conducted to evaluate the potency of four commonly used infectious bursal disease (IBD) live vaccines to determine the most appropriate vaccination response to establish the most appropriate vaccination programme against IBD in Nigeria. A total of 700 day old cockerels were randomly divided into six groups 1, 2, 3, 4, 5, and 6. Groups 1 to 4 were the vaccination cockerels while Groups 5 and 6 were the positive and negative controls. The chicks were sub divided into five groups A, B, C, D and E representing the different schedules that is, 1 and 3 weeks, 2 and 4 weeks, 3 and 5, 1, 3 and 5, 2, 4 and 6 weeks, respectively. After each vaccination, the chicks were observed for clinical signs of IBD. Two weeks after each vaccination, chicks were challenged with IBD virus, onset of clinical signs, morbidity and mortality rates were observed. Sample of bursa was collected from 5 birds at 3 and 7 days post challenge from dead as well as necropsied birds. The lesions were scored on the scale of 0 to 5 (mild to severe). Vaccine 3 appeared to be the best with the mean of 1.8 for gross lesions, 1.2 for histo-pathological lesions, 0.6 for clinical signs, 0.6 for mortality, 0.2 for antibody titre and 1.8 for bursal body weight ratio. Schedule A (vaccination at 1 and 3 weeks) also was the best for all the vaccines. Therefore, Nigerian poultry farmers are advised base on the aforementioned result to use vaccine 3 and schedule A in the control the outbreaks of IBD. Key words: Cockerels chicks, live Infectious bursal disease (IBD) vaccines, potency, vaccination schedule, vaccination strategies.

Chlamydotis macqueenii and C. undulata (Aves: Otididae) are new hosts for Caryospora megafalconis (Apicomplexa: Eimeriidae) and proposal of the genus Avispora gen. nov.

Oocysts of a coccidian morphologically matching features of Caryospora megafalconis Klüh, 1994 were found in fecal samples and contents of the large intestines in five wild caught Clamydotis macqueenii (Gray) and 19 captive bred C. undulata (Jaquin). Scrapings of the intestinal mucosa of necropsied birds revealed macrogamonts and unsporulated oocysts. Sporulation in a potassium dichromate solution at 26°C was completed in 48h. Intestinal contents and sporulated oocysts obtained from feces of infected bustards as well as sporulated oocysts of C. megafalconis and C. neofalconis Böer, 1982 from two Falco rusticolis Linnaeus and one F. peregrinus Tunstall were used for DNA sequencing of the cox1, 18S ribosomal ribonucleic acid (rRNA), and 28S rRNA genes. The phylogenetic trees for all three genes showed that sequences of the material from bustards were identical with C. megafalconis from falcons. C. neofalconis and C. daceloe Yang et al., 2014 were situated in the neighboring clades. Contrary to this, subsequent sequences of C. bigenetica Wacha and Christiansen, 1982 from rattlesakes are at a distinct distance suggesting that despite morphological similarities of the oocysts, there are differences between Caryospora species of birds and reptiles. For this reason, it might be reasonable to transfer avian Caryospora species into a new genus Avispora.

Molecular Diagnosis of Beak and Feather Disease in Native Brazilian Psittacines

The incidence of the psittacine beak and feather disease virus (BFDV) was investigated in Brazilian native parrots with normal feathering arriving at rescue and triage centers for wild animals (CETAS, IBAMA) in the state of Minas Gerais, Brazil. BFDV DNA was investigated by previously described PCR technique for the partial amplification of BFDV ORF-1 in DNA extracts from blood, cloacal swab or liver of psittacines. Some birds provided more than one sample. Nine species of psittacines were sampled between January 2009 and October 2010. Blood (n=46) or cloacal swab (n=128) samples were obtained from psittacines immediately upon arrival at the triage centers. Liver samples were collected from necropsied birds dead on arrival (n=167). All swab samples were negative, except for one Ara ararauna individual (n=3) which blood presented the BFDV DNA. On the other hand, 11 liver samples were positive for BFDV DNA, with a prevalence of 7.8% in Amazona aestiva (n=140). No BFDV DNA was detected in the liver of Amazona amazonica (n=11), A. vinacea (n=5), A. rhodochorytha (n=4), Anodorhynchus hyacinthinus (n=3), Ara ararauna, (n=3), Aratinga leucophtalma (n=2), Guarouba guarouba (n=1) and Pionus maximiliani (n=1). In most cases, alopecia was not associated with BFDV detection in liver, and liver histopathology was inconclusive. Although all cloacal swab samples were negative, a few psittacines (n=19) that died at CETAS-Belo Horizonte were retested, and 21% were detected as positive in liver. A group of psittacines (n=16) was clinically evaluated, and despite showing feather dystrophy, all birds were negative in the cloacal swabs, except for one, which blood sample was positive (A. ararauna). The obtained sequences of the BFDV strains BH 215 and BH 732 were deposited in the GenBank (JQ649409 and JQ649410). A 98% similarity with strain sequences described in Australia, Japan, and New Zealand was observed. It is possible that these strains arrived in Brazil through the legal and illegal trade of parrots. However, it was not possible to associate BFDV infection with the geographical origin of birds and no local marker was detected. The rates of detection, although similar to other studies, indicate the tendency of a high incidence of the disease, possibly associated with stress, and high bird density and wide transmission in captivity conditions.

Histopathological and immunohistochemical diagnosis of infectious bursal disease in poultry birds.

Aim:The aim of the present study was to diagnose infectious bursal disease (IBD) using gross, histopathological, and immunopathological approaches and to compare efficacy of immunohistochemical techniques with conventional diagnostic techniques.Materials and Methods:A total of 33 samples were collected from the six different poultry farms from Ludhiana and the nearby districts. Upon gross analysis of the necropsied birds, the relevant tissue samples such as bursa, kidney, junction of proventriculus and gizzard, heart, and muscles were then processed for histopathological and immunohistochemical studies.Results:Varied macroscopic changes were noted in bursa, characterized as swollen, hemorrhages to atrophy in size. Nonetheless, hemorrhages over thigh muscles were rarely seen. Histologically, the bursa showed prominent fibrotic and atrophic changes. Rarefaction of bursal follicles with intermittent infiltration of lympho-mononuclear cells with chronic cystic changes was additional changes, considered to be paramount for IBD. Expression and localization of IBD specific viral antigens were noticed mainly intracellular to the rarefied areas of bursal follicle section(s), in conjunction to inner lining of the cystic cavities of affected follicles. In addition, the junction of proventriculus and gizzard, the heart muscle, respiratory ciliated epithelium, and proventriculus also revealed positive expression to IBD virus (IBDV) antigen. Advanced immunopathological techniques, i.e., immunofluorescence further testified the evidence of antigen as positive green signal within affected follicles. Further consideration to the reliability of various techniques employed, positive correlation (r=0.64623) was emerged out with conventional pathological scoring.Conclusion:It is concluded that the bursa acts as an organ of choice for demonstrating IBDV antigen for specific diagnosis of disease using immunohistochemistry (IHC), and IHC staining is a precise, specific, rapid, and reliable method to demonstrate the IBDV antigen in the altered tissues due to IBDV infection.

Host-specific exposure and fatal neurologic disease in wild raptors from highly pathogenic avian influenza virus H5N1 during the 2006 outbreak in Germany.

Raptors may contract highly pathogenic avian influenza virus H5N1 by hunting or scavenging infected prey. However, natural H5N1 infection in raptors is rarely reported. Therefore, we tested raptors found dead during an H5N1 outbreak in wild waterbirds in Mecklenburg-Western Pomerania, Germany, in 2006 for H5N1-associated disease. We tested 624 raptors of nine species—common buzzard (385), Eurasian sparrowhawk (111), common kestrel (38), undetermined species of buzzard (36), white-tailed sea eagle (19), undetermined species of raptor (12), northern goshawk (10), peregrine falcon (6), red kite (3), rough-legged buzzard (3), and western marsh-harrier (1)—for H5N1 infection in tracheal or combined tracheal/cloacal swabs of all birds, and on major tissues of all white-tailed sea eagles. H5N1 infection was detected in two species: common buzzard (12 positive, 3.1%) and peregrine falcon (2 positive, 33.3%). In all necropsied birds (both peregrine falcons and the six freshest common buzzards), H5N1 was found most consistently and at the highest concentration in the brain, and the main H5N1-associated lesion was marked non-suppurative encephalitis. Other H5N1-associated lesions occurred in air sac, lung, oviduct, heart, pancreas, coelomic ganglion, and adrenal gland. Our results show that the main cause of death in H5N1-positive raptors was encephalitis. Our results imply that H5N1 outbreaks in wild waterbirds are more likely to lead to exposure to and mortality from H5N1 in raptors that hunt or scavenge medium-sized birds, such as common buzzards and peregrine falcons, than in raptors that hunt small birds and do not scavenge, such as Eurasian sparrowhawks and common kestrels.

Northern fowl mite (Ornithonyssus sylviarum) in Sweden

Haematophagous mites were collected from the vent region and plumage of chickens in six hobby flocks of ornamental breeds in Sweden, one of which included turkeys. Soiled vent skin and feathers, dermatitis, hyperkeratosis, skin necroses and ulcers were observed in 12 necropsied birds from two of the flocks. The mites were identified as the northern fowl mite Ornithonyssus sylviarum (Mesostigmata: Macronyssidae). This was supported by sequence analysis of a 642-bp region in the mitochondrial cytochrome oxidase subunit 1 (COI) gene (COI) in mites collected from five flocks, which showed 97-99% sequence similarity to O. sylviarum by blast analysis. Pairwise sequence comparisons revealed nucleotide variations in the range of 0-2.8%, whereas amino acid sequences were highly conserved. This paper represents one of very few records of O. sylviarum in European poultry, and is the first to report COI sequence data for O. sylviarum from poultry in Europe.