Chlorophacinone exposure causing an epizootic of acute fatal hemorrhage in lambs.

This report describes an epizootic of chlorophacinone toxicosis in lambs with severe acute hemorrhages. Eleven lambs, approximately 1-2 months of age, suddenly developed epistaxis, respiratory distress, and facial and cervical swelling. Affected animals died within 1-2 hours from the onset of clinical signs. Two lambs were available for complete postmortem examination. Gross lesions included mucosal and organ pallor, icterus, melena, and lung edema, as well as thymic, cervical muscle, and intra-articular hemorrhage. Histologically hepatocellular centrolobular necrosis was observed. The anticoagulant chlorophacinone was detected in the livers at 0.58 ppm and 0.50 ppm (wet weight), respectively. The source of exposure to chlorophacinone was old bait material placed between the wall studs of the building housing the ewes and lambs. The lambs were able to reach the bait through a hole in the plywood interior wall of the building.     

Neurotropism of highly pathogenic avian influenza virus A/chicken/Indonesia/2003 (H5N1) in experimentally infected pigeons (Columbia livia f. domestica)

This investigation assessed the susceptibility of experimentally infected pigeons to the highly pathogenic avian influenza virus (HPAIV) H5N1 that caused recent outbreaks of avian influenza in birds and humans in several countries of Asia. For this purpose 14 pigeons were infected ocularly and nasally with 10(8) EID50 and clinical signs were recorded and compared with five chickens infected simultaneously as positive controls. The chickens demonstrated anorexia, depression, and 100% mortality within 2 days postinoculation. Three of the pigeons died after a history of depression and severe neurological signs consisting of paresis to paralysis, mild enteric hemorrhage, resulting in a mortality of 21%. Gross lesions in these pigeons were mild and inconsistent. Occasionally subcutaneous hyperemia and hemorrhage and cerebral malacia were observed. Microscopic lesions and detection of viral antigen were confined to the central nervous system of these pigeons. In the cerebrum and to a minor extent in the brain stem a lymphohistiocytic meningoencephalitis with disseminated neuronal and glial cell necrosis, perivascular cuffing, glial nodules, and in one bird focally extensive liquefactive necrosis could be observed. The remaining nine pigeons showed neither clinical signs nor gross or histological lesions associated with avian influenza, although seroconversion against H5 indicated that they had been infected. These results confirm that pigeons are susceptible to HPAIV A/chicken/Indonesia/2003 (H5N1) and that the disease is associated with the neurotropism of this virus. Although sentinel chickens and most pigeons did not develop disease, further experiments have to elucidate whether or not Columbiformes are involved in transmission and spread of highly pathogenic avian influenza.     

Postural and neurological deficits in broiler chicks after cervical vaccination with live vaccine.

A disease characterized by paresis and paralysis was seen in 7-9-day-old broiler chicks after vaccination in the neck area at day-of-age with a live virus vaccine containing viruses of Marek's disease, fowl pox, and infectious bursal disease. Affected birds presented with variable signs of ataxia, lateral recumbency, leg paralysis, and twisting or S-shaped flexure of the neck. Gross lesions noted at necropsy included swelling and edema of the subcutaneous tissues and muscles of the neck at the injection site area. A heavy mononuclear inflammatory cell infiltration was seen in the subcutaneous tissues, connective tissues, and muscles of the neck at the injection site. In some cases, the inflammatory process extended along fascial planes to involve the epidural spaces surrounding the spinal cord. Fatty changes with possible demyelination of nerve fibers were noted in some sections of the spinal cord adjacent to the inflammatory lesions. Clusters of poxviruses were found within some inflammatory lesions on transmission electron photomicrographs.     

Plasma biochemistry in pigeons experimentally infected with Salmonella.

Ten pigeons were crop inoculated with 1 x 10(9) colony-forming units of Salmonella typhimurium var. Copenhagen and observed during 28 days. Ten sham-inoculated pigeons served as noninfected controls. Clinical signs after Salmonella infection consisted of polydipsia, polyuria, and diarrhea. Morbidity was 90%, but there was no mortality. All inoculated pigeons showed fecal excretion of Salmonella for at least 7 days. Biochemical analysis of plasma samples taken at 3-day intervals indicated decreased concentrations of creatine kinase (CK)-MM and CK-MB isoenzymes and elevated total protein and alpha- and gamma-globulin values. No consistent changes in the level of 17 other blood parameters were observed. After 28 days, all pigeons were necropsied. Gross lesions and bacteriologic and histologic examination indicated septicemia in all Salmonella-inoculated pigeons. Results indicate that Salmonella septicemia in pigeons induces only limited changes in biochemical blood parameters. Decreased CK concentration was a consistent finding, however, and may therefore be a useful aid in the diagnosis of salmonellosis in pigeons.     

Avian adenovirus isolated from pigeons affected with inclusion body hepatitis

Avian adenoviruses were isolated from two pigeons affected with inclusion body hepatitis (IBH) by using chicken embryo liver cell cultures. One of the isolates, designated strain S-PL1, replicated in the cell nuclei forming intranuclear inclusion bodies, showed adenovirus-like morphology by electron microscopy, and cross-reacted serologically with strain SR-48 known as serotype 2 of fowl adenovirus. The strain S-PL1 killed day-old chicks by subcutaneous inoculation, and its 50% chicken lethal dose was 10(3.8) plaque forming units per bird. Severe lesions characterized with IBH and pancreatitis, were produced in chicks inoculated with the virus. Intranuclear inclusion bodies were also recognized in the liver, pancreas, kidney, proventriculus, small intestine, and caecum. By indirect immunofluorescence test, intranuclear viral antigens were detected in the liver, pancreas and other tissues.     

Outbreak of Mycobacterium avium subsp. avium infection in one flock of domestic pigeons

An outbreak of Mycobacterium avium subsp. avium infection was diagnosed in one breed of domestic pigeons (Columba livia f. domestica) in the Czech Republic. Nodular granulomatous lesions were found in 42 (9.7%) pigeons of the 435 examined; histopathologic examination of livers with gross lesions of mycobacteriosis from 15 randomly selected pigeons revealed granulomatous inflammation typical for avian mycobacteriosis in all samples. Direct Ziehl-Neelsen (ZN) microscopy and conventional culture were performed for a total of 117 liver samples (42 pigeons with nodular lesions, 55 randomly selected pigeons without nodular lesions, and 20 randomly selected squabs). Acid-fast bacilli were observed in 19 (16.2%), and conventional culture yielded growth of M. a. avium in 40 (34.2%) liver samples. A triplex quantitative real-time PCR assay based on the IS901 detection system was performed successfully in 115 liver samples and revealed M. a. avium in 63 (54.8%) of them. Mycobacterium a. avium was also detected in two squabs. Eight domestic rabbits (Oryctolagus cuniculus f. domestica) living in the breeding facility were also examined. Pyogranulomatous lesions were only found in one adult male rabbit. At necropsy, both direct ZN microscopy and culture gave negative results for mycobacteria in all examined rabbit tissues. Mycobacterium a. avium was diagnosed in a liver sample of one juvenile rabbit using triplex qPCR, suggesting that M. a. avium infection can occur as early as juvenile animals.     

A comparative study of pigeons and chickens experimentally infected with PPMV-1 to determine antigenic relationships between PPMV-1 and NDV strains

To compare the pathogenicity of PPMV-1 in pigeons and chickens, both species of birds were experimentally infected with strain pi/CH/LHLJ/110822, which was isolated from a pigeon in China. The clinical signs, gross lesions, and histopathological changes were observed in pigeons inoculated with pi/CH/LHLJ/110822. The morbidity and mortality rates were 80% and 70% in pigeons, respectively, whereas there were no clinical signs or gross lesions in chickens inoculated with the same strain. The viral loads in tissue samples were detected by real-time RT-PCR, indicating that six tissue samples (i.e., kidney, lung, brain, trachea, Harderian glands, and proventriculus) had detectable viral RNA in all dead pigeons, and significant differences in viral loads between pigeons and chickens were observed in several tissue samples (i.e., Harderian glands, proventriculus, duodenum, pancreas, small intestine, and large intestine) on 3 days post-inoculation (dpi) and in brain tissue on 7 dpi. In general, viral loads in pigeons were higher than those in chickens, whereas antibody titers in pigeons were lower than those in chickens. These results showed differences in pathogenicity, efficiency of viral RNA replication, and humoral immunity, indicating different susceptibilities between the host species. Additionally, the cross hemagglutination inhibition assay and cross virus neutralization tests demonstrated that pi/CH/LHLJ/110822 antigenicity was different from those of strains La Sota and F48E9.     

Clinical evaluation of random skin flaps based on the subdermal plexus secured with sutures or sutures and cyanoacrylate adhesive for reconstructive surgery in dogs

OBJECTIVE: To evaluate the use of subdermal plexus skin flaps for closing defects after excision of cutaneous and subcutaneous tumors in dogs and to compare outcome of flaps secured with sutures and those secured with butyl-cyanoacrylate and intermittent sutures. STUDY DESIGN: Clinical study. ANIMALS: Fifteen dogs. METHODS: After excision of cutaneous or subcutaneous tumors the skin defect was reconstructed by random flaps based on the subdermal plexus. Flap skin edges were apposed with simple interrupted 4-0 monofilament nylon sutures (group 1; 5 dogs) or nylon sutures alternated with butyl-cyanoacrylate adhesive (group 2; 10 dogs). Flaps were evaluated every 48 hours when bandages were changed, until complete healing. RESULTS: Random flaps based on the subdermal plexus were effectively used to close wound defects; mean flap survival was 89%. Partial flap necrosis occurred in 4 dogs. Wound margins apposed with butyl-cyanoacrylate had thinner and more esthetic scars than sutured margins. CONCLUSION: Random flaps based on the subdermal plexus proved to be versatile for covering limb wounds after excision of cutaneous or subcutaneous tumors. Mean survival rate was comparable to that reported for axial pattern flaps. Butyl-cyanoacrylate adhesive was easy to apply, allowed accurate margin apposition with good cosmetic outcome and reduced sutures needed. CLINICAL RELEVANCE: Cyanoacrylate adhesive should be considered in lieu of suture closure to secure random skin flaps based on the subdermal plexus in dogs.     

Diarrhea associated with myenteric ganglionitis in a dog

Diarrhea in a Border Terrier was associated with inflammatory lesions of the myenteric plexus. This lesion has been documented rarely in dogs. It is speculated that the myenteric plexus lesions were responsible for an autonomic nervous system dysfunction, which resulted in extreme intestinal hypermotility and subsequent diarrhea. Suggested tests for dogs suspected to have autonomic dysfunction are given.     

The effect of animal health products on the formation of injection site lesions in subprimals of experimentally injected beef calves

Two hundred and twenty beef calves were used in an experimental study to determine the occurrence of injection site lesions at slaughter (15 to 18 months of age) following subcutaneous and intramuscular injection of various products into the top hip (top butt), thigh (round), and neck or rib of calves at birth, branding, or weaning. Products tested were: 2 different preparations of selenium; a 2-way, a 7-way, and an 8-way clostridial bacterin; 2 combination 7-way clostridial and Haemophilus somnus bacterins; 2 H. somnus bacterins; 2 different 4-way modified-live viral respiratory vaccines; a 4-way killed viral and H. somnus vaccine; and penicillin, florfenicol, ceftiofur, trimethoprim-sulfa, and tilmicosin. The occurrence of lesions, number of steaks affected with lesions, the trim weight of lesions, the histological class of lesions, and the estimated economic losses are described. Generally, products administered subcutaneously in the neck produced minimal tissue damage and economic losses.     

Experimental inoculation of pigeons (Columba livia) with Mycobacterium bovis

The purpose of this pilot study was to determine if pigeons (Columba livia) are susceptible to infection with Mycobacterium bovis by either oral or intratracheal inoculation and to assess their possible role in the lateral transmission of bovine tuberculosis. Six pigeons were orally inoculated with 1.3 x 10(5) colony-forming units of M. bovis, six pigeons were intratracheally inoculated with the same dose, and six pigeons served as noninoculated controls. The study continued for 90 days postinoculation (PI), with groups of birds necropsied at 30-day intervals, and fecal samples and tissues were collected for mycobacterial culture. Two pigeons, one intratracheally inoculated and one orally inoculated, shed M. bovis in their feces at 1 day PI, and one intratracheally inoculated bird shed M. bovis in its feces 60 days PI. Whereas no illness or weight loss was present during the course of the study, 2 of 12 inoculated birds exhibited microscopic lesions of mycobacteriosis, and the organism was isolated from tissues of three inoculated birds. Pigeons are susceptible to infection with M. bovis after high dose inoculation and can shed the organism in their feces for up to 60 days PI; intratracheally inoculated birds appear more likely to become active fecal shedders of M. bovis. Although these were high dose inoculations under experimental conditions, pigeons may potentially play a role in the lateral transmission of bovine tuberculosis between infected and uninfected mammalian hosts.     

耕作方式和秸秆覆盖对旱地麦豆轮作下小麦籽粒产量、蛋白质含量和土壤硝态氮残留的影响

为明确耕作方式和秸秆覆盖对旱地麦豆轮作下小麦籽粒产量、蛋白质含量和土壤硝态氮残留的影响,2014年10月-2016年6月,利用设置在豫西典型旱作区的麦豆轮作栽培模式长期定位试验,选取传统翻耕、翻耕覆盖、旋耕和旋耕覆盖4个处理,比较了小麦氮素吸收利用、籽粒产量、蛋白质含量以及土壤硝态氮残留量。结果表明,与翻耕相比,旋耕不影响小麦产量,但花后氮素积累量、籽粒蛋白质含量和蛋白质产量分别降低60.0%、8.6%和13.0%,而成熟期0~200 cm土层硝态氮残留量显著提高28.6%。同一耕作方式下,秸秆覆盖较无覆盖不仅显著提高了穗数、穗粒数、千粒重和收获指数,还提高了拔节前和开花后的氮素积累量,促进了营养器官氮素向籽粒中转运,从而使翻耕覆盖的籽粒产量、氮素吸收效率、籽粒蛋白质含量和蛋白质产量较翻耕分别提高11.5%、13.5%、7.4%和21.3%,旋耕覆盖较旋耕也分别提高23.0%、39.5%、12.8%和38.5%。在试验进行7年后的小麦成熟期,翻耕覆盖0~200 cm土层硝态氮残留量较翻耕降低31.3%,旋耕覆盖较旋耕也降低51.4%。因此,秸秆覆盖不仅可提高旱地麦豆轮作下小麦产量、蛋白质含量和氮素吸收效率,还能降低土壤硝态氮的残留量,是兼顾旱地小麦高产优质和环境友好生产的有效途径,尤其以旋耕覆盖效果突出。     

Free choice feeding of whole grains in meat-type pigeons: 1. effect on performance,carcass traits and organ development

1. The effects of 5 different feeding systems on the performance, carcass traits and organ development were studied in pigeon squabs.

2. The 5 treatments were (1) whole grains of maize, pea and wheat plus concentrate feed; (2)whole grains of maize and wheat plus concentrate feed (CWC); (3) whole grains of maize and pea plus concentrate feed; (4)whole grain of maize plus concentrate feed (CC); and (5) compound feed (CF).

3. Feed intake of parent pigeons increased significantly from 0 to 21 d and it was higher in the CF treatment. Body weight of squabs in the CWC treatment was the highest among the 5 treatments in 4 weeks. Body weight losses of parental pigeons during the rearing period were not significantly different among the 5 treatments.

4. Protein intake in CC and CWC treatments was lower than that of the other three treatments. The CWC treatment had the highest daily weight gain and the lowest feed conversion ratio. Treatments were statistically similar in the relative weight of carcass, breast and thigh. CF had the lower relative weight of abdominal fat.

5. Relative weight of gizzard in the CF treatment was significantly lower than that of CWC.

6. It was concluded that the application of free choice feeding of whole grains of maize and wheat plus concentrate feed increased the body weight of 28-d-old pigeon squabs and decreased the feed conversion rate of parent pigeons. This feeding strategy could be commercially interesting in meat-type pigeon production.

     

Pathologic changes in pigeons infected with a virulent Trichomonas gallinae strain (Eiberg)

Trichomonas gallinae, Eiberg strain, is a virulent hepatotropic flagellate parasite of pigeons. The parasite initially infects the upper digestive tract, causing the formation of ulcers, which allow it to enter the circulatory system. The trichomonads later gain access to the liver, where they cause the formation of caseous lesions. Vascular congestion and perivascular cuffing in the liver were seen as early as 4 days postinfection (PI). By day 7 PI, a marked reduction in abdominal fat and hepatosplenomegaly was evident. Hepatocytes underwent fatty degeneration (seen by day 7 PI) before total necrosis set in. On day 8 PI, trichomonads could be found among the necrotic hepatocytes in caseous lesions. These lesions were delineated by a wall of leukocytes and occasional giant cells. Nonimmune pigeons died within 14 to 17 days PI of liver dysfunction. Other organs (kidney and genitalia) were also seen to undergo degeneration. These manifestations probably reflect the progression of liver dysfunction.     

Survey of the pathologic findings in a large production colony of pigeons, with special reference to pseudomembranous stomatitis and nephritis

Pathologic evaluations of pigeons dying between September 1984 and August 1985 are reported for a production colony of 1200-1800 White Carneau and Show Racer pigeons ranging in age from hatchlings to 12 years. Infectious diseases were the common causes of death in pigeons younger than 1 year; salmonellosis and nephritis were the common causes in pigeons 1-3 years old; and neoplasia and reproductive organ disorders were the common causes in pigeons older than 3 years. Monthly mortality was 2-4% in pigeons fed a cholesterol-containing diet and 0.9% in those fed noncholesterol-containing pellet diets. The increased deaths in the cholesterol-fed birds were attributed primarily to end-stage renal disease and atherosclerosis with secondary complications. The most frequently observed clinical entity in pigeons younger than 6 months was pseudomembrane formation on the oral and pharyngeal mucosa, termed pseudomembranous stomatitis. The definitive etiologic factor was not determined. Although all affected pigeons had similar gross lesions, the cases fell into one of three subsets, suggestive of bacterial, fungal, or viral etiologies. Chronic nephritis occurring as end-stage renal disease was more severe in pigeons fed a cholesterol-containing diet.     

Assessment of ruminal degradation, oral bioavailability, and toxic effects of anticoagulant rodenticides in sheep

OBJECTIVE: To assess the rate and extent of ruminal degradation of warfarin, chlorophacinone, and bromadiolone in vitro and determine the oral availability and clinical and hemostatic effects of each anticoagulant rodenticide in adult sheep. ANIMALS: 3 Texel sheep. PROCEDURE: Samples of ruminal fluid were incubated with each of the anticoagulants to assess the kinetics of ruminal degradation over 24 hours. To determine the plasma kinetics of the anticoagulants, each sheep received each of the anticoagulants IV or via a rumenimplanted cannula at 2-month intervals (3 rodenticide exposures/sheep). At intervals during a 240- to 360- hour period after treatment, prothrombin time (PT) was measured, plasma anticoagulant concentration was assessed, and clinical signs of rodenticide poisoning were monitored. In plasma and rumen extracts, anticoagulant concentrations were determined via high-performance liquid chromatography. RESULTS: In the rumen extracts, anticoagulants were slightly degraded (< 15%) over 24 hours. In vivo, oral availability of warfarin, chlorophacinone, and bromadiolone was estimated at 79%, 92%, and 88%, respectively. Although maximum PT was 80 seconds after chlorophacinone and bromadiolone treatments, no clinical signs of toxicosis were detected; PT returned to baseline values within 2 weeks. CONCLUSIONS AND CLINICAL RELEVANCE: In sheep, warfarin, chlorophacinone, and bromadiolone were not degraded in the rumen but their bioavailabilities were high after oral administration; the kinetics of these compounds in sheep and other mammals are quite similar. These data suggest that the lack of susceptibility of ruminants to these anticoagulant rodenticides cannot be explained by either ruminal degradation or the specific toxicokinetics of these anticoagulants.     

Designing a treatment protocol with voriconazole to eliminate Aspergillus fumigatus from experimentally inoculated pigeons

To investigate the efficacy of voriconazole for the treatment of aspergillosis, three groups of six racing pigeons (Columba livia domestica) were inoculated in the apical part of the right lung with 2 × 10⁷ conidia of an avian derived Aspergillus fumigatus strain. The minimal inhibitory concentration of voriconazole for this strain was 0.25 μg/ml. In two groups, voriconazole treatment was started upon appearance of the first clinical signs and continued for fourteen days. The third group was sham treated. The voriconazole-treated pigeons received voriconazole orally at a dose of 10 mg/kg body weight (BW) q12h (group 1) or 20 mg/kg BW q24h (group 2). Sixteen days post-inoculation all surviving pigeons were euthanized. Weight loss, clinical scores, daily mortality, lesions at necropsy and isolation of A. fumigatus were compared between all groups. In both voriconazole-treated groups, a significant reduction in clinical signs and lesions was observed. Administering voriconazole at 10 mg/kg BW q12h eliminated A. fumigatus and administering voriconazole at 20 mg/kg BW q24h reduced A. fumigatus isolation rates. Mild histological liver abnormalities were found in group 1 (10 mg/kg BW q12h), while mild histological as well as macroscopic liver abnormalities were found in group 2 (20 mg/kg BW q24h).In conclusion, voriconazole at 10 mg/kg BW q12h in pigeons reduces clinical signs and eliminates A. fumigatus in racing pigeons experimentally infected with A. fumigatus.     

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.

     

Outbreak of avian mycobacteriosis in a flock of two-year-old domestic pigeons (Columba livia f. domestica)

This report describes an outbreak of avian mycobacteriosis in a flock of 100 two-yr-old pigeons. Over a 6-mo period, the sick pigeons showed cachexia followed by death. In Columbiformes classic tubercles rarely develop, but in these affected pigeons granulomatous nodular lesions of various sizes, containing numerous acid-fast bacilli, were found in the internal organs. The lesions were observed in the liver, spleen, intestine, bone marrow, ovary, and oviduct. Despite their breeding age, atrophy was also found in the ovary and oviduct. Microorganisms belonging to Mycobacterium avium complex were identified in the affected tissues by polymerase chain reaction.