Paramyxovirus-1 in feral pigeons (Columba livia) in Ontario

Paramyxovirus-1 (PMV-1) infection was diagnosed in racing pigeons in Ontario during 1985, but it was not until January 1989, that the virus was isolated from feral pigeons (Columba livia) in this province. During an 18 month period beginning January 1988, a total of 43 feral pigeons was submitted to the Wildlife Diseases Laboratory, Pathology Department, Ontario Veterinary College. A history of neurological signs accompanied most of the birds. Tissues from 29 birds were submitted for PMV-1 isolation. Allantoic inoculation of embryonated chicken eggs yielded PMV-1 in 10 of the pigeons submitted. On the basis of histological criteria, we believe that 12 other birds were also infected with PMV-1.

Gross pathological changes were unremarkable. Lymphplasmacytic interstitial nephritis was observed histologically in all birds from which PMV-1 was isolated. Other lesions seen, in decreasing frequency of occurrence, were lymphoplasmacytic interstitial hepatitis and multifocal hepatic necrosis, lymphoplasmacytic interstitial pancreatitis, nonsuppurative encephalitis and myelitis.

The existence of PMV-1 in feral pigeons poses a potential threat to the poultry population since there is ample opportunity for mingling with poultry under open housing management. There is also a concern that pigeons may harbor the virus, perhaps in the kidney, and become chronic carriers and potential long-term disseminators of the disease.

     

Screening for several potential pathogens in feral pigeons (Columba livia) in Madrid

Background

Pathogens with the zoonotic potential to infect humans, such as Campylobacter jejuni, Campylobacter coli and Chlamydophila psittaci, can be found in feral pigeons (Columba livia). Given the high density of these birds in the public parks and gardens of most cities, they may pose a direct threat to public health.

Methods

A total of 118 pigeons were captured in three samplings carried out in 2006-2007 in public parks and gardens in Madrid, Spain. Standard haematological and morphological analyses were carried out on the pigeons. PCR was used to screen for the presence of Campylobacter jejuni, C. coli and Chlamydophila psittaci. Positive samples were confirmed by DNA sequencing.

Results

The analyses demonstrated a high prevalence of Chlamydophila psittaci (52.6%) and Campylobacter jejuni (69.1%) among the birds captured. In contrast, Campylobacter coli was rarely detected (1.1%).

Conclusions

Pigeons in Madrid can carry Chlamydophila psittaci and Campylobacter jejuni. They may be asymptomatic or subclinical carriers of both pathogens.     

Screening of feral pigeon (Colomba livia), mallard (Anas platyrhynchos) and graylag goose (Anser anser) populations for Campylobacter spp., Salmonella spp., avian influenza virus and avian paramyxovirus

A total of 119 fresh faecal samples were collected from graylag geese migrating northwards in April. Also, cloacal swabs were taken from 100 carcasses of graylag geese shot during the hunting season in August. In addition, samples were taken from 200 feral pigeons and five mallards. The cultivation of bacteria detected Campylobacter jejuni jejuni in six of the pigeons, and in one of the mallards. Salmonella diarizona 14: k: z53 was detected in one graylag goose, while all pigeons and mallards were negative for salmonellae. No avian paramyxovirus was found in any of the samples tested. One mallard, from an Oslo river, was influenza A virus positive, confirmed by RT-PCR and by inoculation of embryonated eggs. The isolate termed A/Duck/Norway/ 1/03 was found to be of H3N8 type based on sequence analyses of the hemagglutinin and neuraminidase segments, and serological tests. This is the first time an avian influenza virus has been isolated in Norway. The study demonstrates that the wild bird species examined may constitute a reservoir for important bird pathogens and zoonotic agents in Norway.     

Pharmacokinetics and bioavailability of erythromycin in pigeons (Columba livia)

Tissue and plasma concentrations were determined after intravenous and oral administration of erythromycin to pigeons to establish the pharmacokinetics and bioavailability of the drug. A short mean half-life of elimination of 0.9 h was found. The relative bioavailability after direct crop administration of erythromycin thiocyanate or erythromycin ethylsuccinate at a dosage rate of 100 mg/kg was less than 10%. At a drug concentration in drinking water of 1 g/l, erythromycin plasma levels were barely detectable, whilst lung and trachea concentrations reached a maximum of 1.6 micrograms/ml. Even after crop administration of 100-mg/kg erythromycin thiocyanate, low plasma levels were obtained, whilst lung and trachea concentrations were substantially higher. Prescribed drinking-water regimens seemed unable to yield therapeutic tissue concentrations. Only individual crop administration seemed an appropriate medication method. The use of erythromycin ethylsuccinate did not present any advantage in comparison with erythromycin thiocyanate.     

Prevalence and risk factors for Salmonella spp. and Campylobacter spp. caecal colonization in broiler chicken and turkey flocks slaughtered in Quebec, Canada

We conducted an observational study to estimate prevalence and risk factors for Salmonella spp. and Campylobacter spp. caecal colonization in poultry. Eighty-one broiler chicken and 59 turkey flocks selected among flocks slaughtered in the province of Quebec, Canada, were included in the study. Flock status was evaluated by culturing pooled caecal contents from about 30 birds per flock. Exposure to potential risk factors was evaluated with a questionnaire. Odds ratios were computed using multivariable logistic regression.

The prevalence of Salmonella-positive flocks was 50% (95% CI: 37, 64) for chickens and 54% (95% CI: 39, 70) for turkeys, respectively. Odds of Salmonella colonization were 2.6 times greater for chicken flocks which failed to lock the chicken house permanently. In turkeys, odds of Salmonella colonization were 4.8–7.7 times greater for flocks which failed to be raised by ≤2 producers with no other visitors allowed onto the premises, or origin from a hatchery.

The prevalence of Campylobacter-positive flocks was 35% (95% CI: 22, 49) for chickens and 46% (95% CI: 30, 62) for turkeys. Odds of colonization were 4.1 times higher for chicken flocks raised on farms with professional rodent control and 5.2 times higher for flocks with manure heap >200 m from the poultry house, and also increased with the number of birds raised per year on the farm and with the age at slaughter. For turkeys, odds of Campylobacter flock colonization were 3.2 times greater in flocks having a manure heap at ≤200 m from poultry house and 4.2 times greater in flocks drinking unchlorinated water.     

Safety and efficacy of clavulanate-potentiated amoxycillin in pigeons (Columba livia)

Pigeons treated orally with 125 mg clavulanate-potentiated amoxycillin for seven days showed no adverse reactions. The drug had a marked depressive effect on the faecal flora but this had returned to normal 10 days after cessation of treatment. When administered to pigeons with an experimental Staphylococcus aureus infection of the feet no clinical response was apparent and there was no evidence of a diminution in the inflammatory process.     

Parasites of domestic pigeons (Columba livia domestica) in Sebele, Gaborone, Botswana

The following parasites were found in apparently healthy pigeons kept in Sebele: a haemoprotozoan, Haemoproteus columbae (80%); endoparasite metazoan nematodes, Ascaridia columbae (30%) and Dispharynx spiralis (10%); a cestode, Raillietina sp. (80%) and coccidian oocysts (40%); 2 ectoparasites, namely the pigeon fly, Pseudolynchia canariensis (50%) and the louse, Columbicola columbae (30%). The pigeons also had highantibody titres, (1:256) to the protozoan parasite Toxoplasma gondii (100%). The latter infection in these domestic pigeons has public health implications.     

Prevalence of Salmonella, Yersinia and Campylobacter spp. in feral raccoons (Procyon lotor) and masked palm civets (Paguma larvata) in Japan

To estimate the public and animal health risk that alien species pose, the prevalence of Salmonella, Yersinia, and Campylobacter spp. in feral raccoons (Procyon lotor, n=459) and masked palm civets (Paguma larvata, n=153), which are abundant alien species in Japan, was investigated in urban and suburban areas of Japan. Salmonella enterica was detected from 29 samples [26 raccoons, 5.7%, 95% confidence interval (CI) 7.8-3.5%; three masked palm civets, 2.0%, 95% CI 4.2-0%]. Many of the isolates belonged to serovars that are commonly isolated from human gastroenteritis patients (e.g. S. Infantis, S. Typhimurium, and S. Thompson). The antimicrobial susceptibility test showed that 26.9 % of the isolates from raccoons were resistant to at least one antimicrobial agent, whereas none of the isolates from masked palm civets were resistant. Yersinia sp. was detected from 193 samples (177 raccoons, 38.6%, 95% CI 43.0-34.1%; 16 masked palm civets, 10.5%, 95% CI 15.3-5.6%). All virulent Yersinia strains belonged to Yersinia pseudotuberculosis, which was isolated from seven (1.5%, 95% CI 2.6-0.4%) raccoons and six (3.9%, 95% CI 7.0-0.8%) masked palm civets. According to the detection of virulence factors, all the Y. pseudotuberculosis isolates belonged to the Far Eastern systemic pathogenicity type. Campylobacter spp. was detected from 17 samples (six raccoons, 1.3%, 95% CI 2.3-0.3%; 11 masked palm civets, 7.2%, 95% CI 11.3-3.1%). Among these, three isolates from raccoons were identified as C. jejuni. These results showed that these pathogens can be transmitted by human activities, other wild animals, and the environment to feral raccoons and masked palm civets, and vice versa. As these animals have omnivorous behaviour and a wide range of habitats, they can play an important role in the transmission of the enteric pathogens.     

Examination of Australian backyard poultry for Salmonella,Campylobacter and Shigella spp., and related risk factors

Worldwide, foodborne illness is a significant public health issue in both developed and developing countries. Salmonellosis, campylobacteriosis and shigellosis are common foodborne gastrointestinal illnesses caused by the bacteria Salmonella spp., Campylobacter spp. and Shigella spp. respectively. These zoonotic diseases are frequently linked to eggs and poultry products. The aim of this study was to investigate the presence of these pathogens in Australian backyard poultry flocks and to determine risk factors for these pathogens. Poultry faeces samples were collected from 82 backyards and screened for Salmonella spp., Campylobacter spp. and Shigella spp. using qPCR. A questionnaire was administered to the backyard poultry owners to assess their knowledge regarding management of poultry and eggs and to identify potential risk factors that may contribute to the presence of zoonotic pathogens in the flocks. One composite faecal sample was collected from each backyard (82 samples). Composite sampling here means taking one or more grab samples from a backyard to make up approximately 10 grams. Four per cent of samples, that is 4% backyards tested, were positive for Salmonella spp., 10% were positive for Campylobacter spp. and none were positive for Shigella spp. A higher infection rate was seen in multi-aged flocks (24%) compared with the single-aged flocks (3%). The survey found that many participants were engaging in risky food safety behaviours with 46% of participants responding that they washed their eggs with running water or still water instead of wiping the dirt off with a damp cloth to clean the eggs and 19% stored their eggs at room temperature. This study demonstrated that backyard poultry may pose a potential risk for salmonellosis and campylobacteriosis. Additionally, Australian public health and food safety regulations should be modified and effectively implemented to address the risks associated with backyard poultry husbandry.     

Helminth parasites of domestic pigeons (Columba livia domestica) in Sebele, Gaborone, Botswana

Twelve adult domestic pigeons from Sebele, Gaborone, Botswana, were examined for the presence of helminth parasites. The cestode genus Raillietina and two species of nematodes, Dispharynx spiralis and Ascaridia columbae were recovered. Most pigeons (75 %) were infected with Raillietina spp. often in concurrence with A. columbae.     

Toxoplasma gondii antibodies in common barn-owls (Tyto alba) and pigeons (Columba livia) in New Jersey

In southwestern New Jersey during 1986 and 1987, common barn-owls and pigeons were captured on farmsteads and tested for Toxoplasma gondii antibodies by a modified direct agglutination test. In 1986, 3/28 (10.7%) adult and 0/124 nestling owls tested positive at titers of greater than or equal to 1:40. Additionally, 2/34 (5.9%) pigeons tested had T. gondii antibodies at titer of 1:320. In 1987, 9/38 (27.3%) adult and 18/80 (22.5%) nestling owls tested positive at titers of greater than or equal to 1:25; this includes 3/38 (7.9%) adult and 1/80 (1.3%) nestling owls that tested positive at a titer of 1:50.     

Unusual biphasic disease in domestic pigeons (Columba livia f. domestica) following experimental infection with Sarcocystis calchasi

A novel Sarcocystis species has recently been reported in the domestic pigeon (Columba livia f. domestica) as intermediate host, causing severe central nervous signs similar to Paramyxovirus-1 or Salmonella Typhimurium var. cop. infection. Transmission of the parasite via the northern goshawk (Accipiter gentilis) as definitive host has been established. Experimental infection of domestic pigeons with sporocysts excreted by experimentally infected northern goshawks reproduced the natural infection in the pigeon, proving the causative role of the parasite in the disease. Here, we describe in greater detail the course of the fulminant biphasic disease depending on the infectious dose. Pigeons infected with 10(3) or 10(4) sporocysts showed clinical signs of polyuria and apathy around 10-11 days postinfection (dpi) and sudden neurological signs 51-57 dpi as a second phase of disease. Pigeons infected with higher doses died within 7-12 dpi, also showing polyuria and apathy but without nervous signs. At necropsy, livers and spleens had multifocal necroses and infestations with parasitic stages, namely, schizonts. Moreover, lesions and schizonts were also found in the lung, bone marrow, and next to blood vessels in the connective tissue of various organs. Pigeons infected with 102 sporocysts remained symptomless until 58-65 dpi, when sudden central nervous signs occurred. Major histopathologic findings of pigeons with neurological signs were encephalitis and myositis of virtually every skeletal muscle with high infestations of sarcocysts. Only mild myocarditis and very few cysts were found in the heart muscles. Importantly, a sentinel pigeon developed identical lesions when compared to those of low-dose infected pigeons, suggesting a risk of mechanical transmission of sporocysts from freshly infected to uninfected pigeons in a flock. By contrast, chickens failed to develop any clinical signs or pathologic lesions in the same experiment. The findings further characterize the new highly pathogenic disease in domestic pigeons, which clinically mimics paramyxovirosis and salmonellosis in both phases of the disease and exclude chickens as further intermediate host species.     

Prevalence and risk factors for Campylobacter spp. in chicken broiler flocks in Reunion Island (Indian Ocean)

Our objectives were to determine Campylobacter prevalence in broiler chicken flocks in Reunion Island and to define specific practices associated with the presence of Campylobacter spp. Infection in Reunionese broiler flocks. Fifty broiler flocks were studied in Reunion Island from May 2007 to February 2009. A questionnaire was submitted to the farmers and samples of fresh droppings were collected to assess the flock's Campylobacter status. Fifty four percent of the flocks were infected by Campylobacter spp.: 30% (95% CI: 28.71-31.29) were infected with Campylobacter coli and 17% (95% CI: 15.95-18.05) with Campylobacter jejuni; only 7% (95% CI: 6.28-7.72) were infected by both species at the same time. Several poultry houses in the farm (OR=11.2; [1.05-92]) and cleaning without any detergent (OR=13.1; [2.1-78.3]) increased the risk of Campylobacter infection. A distance higher than 500 m between broiler farms (OR=0.27; [0.1-0.8]) and use of disinfectant during the rearing period decreased this risk of infection (OR=0.15; [0.1-0.75]).     

Heat resistance in liquids of Enterococcus spp., Listeria spp., Escherichia coli, Yersinia enterocolitica, Salmonella spp. and Campylobacter spp

The aim of the work was to collect, evaluate, summarize and compare heat resistance data reported for Campylobacter, Enterococcus, Escherichia, Listeria, Salmonella and Yersinia spp. The work was limited to resistance in liquids with pH values 6-8. Results obtained under similar experimental conditions were sought. Thermal destruction lines for the various bacterial groups studied were constructed using log10 D values and treatment temperatures. There was a good linear relationship between log10 D and temperature with Escherichia coli, listerias and salmonellas. For campylobacters, enterococci and yersinias the relationships were weaker but, nevertheless, present. Using the slopes of the lines and their 95% confidence limits, z values and their 95% confidence limits were calculated. z values were compared with z values obtained from reports. The equations for the lines were also used for calculation of predicted means of D values at various treatment temperatures. 95% confidence limits on predicted means of D values and on predicted individual D values were also calculated. Lines and values are shown in figures and tables. Differences in heat resistance noted between and within the bacterial groups studied are discussed.     

Campylobacter spp., Salmonella spp., Verocytotoxic Escherichia coli,and Antibiotic Resistance in Indicator Organisms in Wild Cervids

Faecal samples were collected, as part of the National Health Surveillance Program for Cervids (HOP) in Norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. Samples from a total of 618 animals were examined for verocytotoxic E. coli (VTEC); 611 animals for Salmonella and 324 animals for Campylobacter. A total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species E. coli and Enterococcus faecalis/E. faecium for antibiotic resistance pattern studies. Salmonella and the potentially human pathogenic verocytotoxic E. coli were not isolated, while Campylobacter jejuni jejuni was found in one roe deer sample only. Antibiotic resistance was found in 13 (7.3%) of the 179 E. coli isolates tested, eight of these being resistant against one type of antibiotic only. The proportion of resistant E. coli isolates was higher in wild reindeer (24%) than in the other cervids (2.2%). E. faecalis or E. faecium were isolated from 19 of the samples, none of these being reindeer. All the strains isolated were resistant against one (84%) or more (16%) antibiotics. A total of 14 E. faecalis-strains were resistant to virginiamycin only. The results indicate that the cervid species studied do not constitute an important infectious reservoir for either the human pathogens or the antibiotic resistant microorganisms included in the study.     

Campylobacter spp., Salmonella spp., verocytotoxic Escherichia coli, and antibiotic resistance in indicator organisms in wild cervids

Faecal samples were collected, as part of the National Health Surveillance Program for Cervids (HOP) in Norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. Samples from a total of 618 animals were examined for verocytotoxic E. coli (VTEC); 611 animals for Salmonella and 324 animals for Campylobacter. A total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species E. coli and Enterococcus faecalis / E. faecium for antibiotic resistance pattern studies. Salmonella and the potentially human pathogenic verocytotoxic E. coli were not isolated, while Campylobacter jejuni jejuni was found in one roe deer sample only. Antibiotic resistance was found in 13 (7.3%) of the 179 E. coli isolates tested, eight of these being resistant against one type of antibiotic only. The proportion of resistant E. coli isolates was higher in wild reindeer (24%) than in the other cervids (2.2%). E. faecalis or E. faecium were isolated from 19 of the samples, none of these being reindeer. All the strains isolated were resistant against one (84%) or more (16%) antibiotics. A total of 14 E. faecalis-strains were resistant to virginiamycin only. The results indicate that the cervid species studied do not constitute an important infectious reservoir for either the human pathogens or the antibiotic resistant microorganisms included in the study.     

Comparative study of ampicillin and amoxycillin after intravenous, intramuscular and oral administration in homing pigeons (Columba livia)

Pharmacokinetics of ampicillin and amoxycillin after intravenous, intramuscular and oral administration was investigated in homing pigeons. The pharmacokinetic parameters in a cross-over study after intravenous administration of the sodium salts were comparable. The only significant difference was found for the distribution phase. The bioavailability after intramuscular injection of the sodium salts was especially low for ampicillin (26 per cent, as against 57 per cent for amoxycillin). The mean peak blood levels at 0.5 hours were 13.65 and 28.80 mg litre-1 for ampicillin and amoxycillin, respectively. After oral administration of trihydrate solutions (8 mg ml-1) the bioavailability was 20 and 35 per cent, respectively, and the mean peak blood levels were 8.46 and 16.98 mg litre-1, found at 1.04 and 1.26 hours. The recovery from the droppings, which include in birds the urine fraction as well, was unexpectedly low. Based on controls for recovery of added penicillin from the droppings and uric acid suspensions, indications were found that the pigeon enzymically inactivates penicillins. The in vitro activity of ampicillin against 266 strains of bacteria isolated from birds was determined. The minimum inhibitory concentration (MIC) for 65.4 per cent of the Escherichia coli was lower than 4 mg litre-1, for 91.1 per cent of the Salmonella species was lower than 2 mg litre-1 and for 100 per cent of the Yersinia pseudotuberculosis was lower than 0.25 mg litre-1. Based on these data and a literature study dosage regimens were calculated for MIC values of 0.5 and 2.5 mg litre-1.     

Physiological and hormonal aspects in female domestic pigeons (Columba livia) associated with breeding stage and experience

The present study examined the changes in serum biochemical values, hormone profiles and ovary prolactin receptor (PRLR) gene expression occurring in female domestic pigeons (Columba livia) under different breeding status and experience. The egg‐laying pigeons had lower calcium, total protein, albumin, prolactin levels and higher oestrogen levels than those of incubating birds (p < 0.05). First‐time breeders had higher (p < 0.05) progesterone levels and lower (p < 0.05) prolactin levels than that of experienced ones. The levels of oestrogen and follicle‐stimulating hormone (FSH) increased with age (p < 0.05). The very old birds showed a pronounced increase (p < 0.05) in PRL, FSH and progesterone and a little decrease in oestrogen. Serum prolactin level was not correlated with the ovary PRLR mRNA expression pattern among all the pigeons. Results showed that serum physiological profile of female pigeons was correlated with breeding status, whereas reproductive hormone levels were correlated with advancing breeding experience. It was concluded that female pigeons had a good ability of recovering from nutrient loss after each breeding attempts, and the degradation of reproductive performance might be attributed to changes in the endocrine system.