Epidemiology and Evolution of Emerging Porcine Circovirus-like Viruses in Pigs with Hemorrhagic Dysentery and Diarrhea Symptoms in Central China from 2018 to 2021

Porcine circovirus-like virus (PCLV) is a type of circular Rep-encoding single-stranded DNA virus and may be associated with the development of diarrheal symptoms in pigs. In this study, we retrospectively analyzed three years of past cases in Anhui, China, and reported a case of hemorrhagic enteritis and death in a pregnant sow possibly caused by PCLV. In addition, we analyzed the evolutionary characteristics of PCLV and found that mutation, recombination and selective pressure all played an important role in the evolution of PCLV. We identified N15D and T17S as well as L56T, T58R, K59Q, M62R, L75I and R190K mutations in two different branches, and we noted recombination events in the Rep of a group of Chinese strains. Analysis of selection pressure revealed that PCLV gained more positive selection, indicating that the virus is in a continuous evolutionary state. The PR2 plot, ENC-plot and neutrality analysis showed a greater role of natural selection than that of mutational pressure in the formation of codon usage patterns. This study is the first to identify PCLV in sows with hemorrhagic dysentery and death, and it provides new epidemiological information on PCLV infection in pigs in China.

Endoparasitoses of the Eurasian collared dove (Streptopelia decaocto) on the northern Black Sea coast of Ukraine

One of the main tasks of ecological parasitology at the present stage is to determine patterns of spread of invasive diseases of poultry in the environment through a thorough epidemiological examination, as well as to determine the main directions and factors of spread of parasites in Ukraine. Some pigeon health problems can affect their populations, but parasitic infections play an important role. Our research found that 83.3% of Eurasian collared doves examined (Streptopelia decaocto) were affected by endoparasites. The commonest helminths were Raillietina spp. with the average invasion intensity of 4.9 ± 1.3 specimens/ind., Baruscapillaria spp. and Ascaridia columbae with an invasion intensity of 4.6 ± 1.5 and 3.7 ± 2.1 specimens/ind., respectively. The commonest cestodes were Raillietina spp. with the extent of invasion of 52.2% and Davainea proglottina – 6.7%. The Amoebotaenia cuneata cestodes were recorded in 3 (3.3%) doves, and Echinolepis carioca – only in 2 (2.2%) doves. Six doves (6.7%) were infected with the nematode Ascaridia columbae and 5 (5.6%) – Baruscapillaria spp. Eimerian oocysts were found in 9 (10%) collared doves, and Trichomonas gallinae was recorded in 15 (16.7%) birds. According to the results of helminthological autopsy and identification of the isolated pathogens, 8 varieties of mixinvasions were identified. In association with the Rayetins, there were the protozoa Eimeria spp. and Trichomonas gallinae and the nematode Ascaridia columbae. Two-component invasions were registered in 78.6% of doves, three-component infestations in 14.3% and four-component infestations in 7.1% of birds. Mixed infection with Raillietina spp. + Ascaridia columbae was found in the small intestine of Streptopelia decaocto, which was also pathomorphologically observed to have catarrhal-hemorrhagic enteritis, which was accompanied by the formation of a large number of spotted hemorrhages on the mucous membrane, and in the places of attachment of cestodes - necrotic-caseous areas. Temperature and other weather conditions such as humidity, precipitation, etc. of the northern Black Sea coast affect the population size of intermediate host cestodes. Continuous monitoring of invasive diseases of pigeons of different species will help to take the necessary preventive measures against endoparasitoses of birds.

Identification and Typing of Canine Parvovirus Using Molecular Techniques

Aim: Canine parvovirus 2, the causative agent of acute hemorrhagic enteritis in dogs, is one of the most important pathogenic viruses. It causes a highly contagious and often fatal disease. The disease condition is complicated further due to emergence of a number of variants namely CPV-2a, CPV-2b, CPV-2c, new CPV 2a, new CPV 2b over the years and involvement of domestic and wild canines. The virus is shed in large numbers in the feces of infected dog and upto 7 to 10 days post-infection, therefore, the present study was designed to detect CPV and to identify the prevailing antigenic types of CPV using molecular techniques from rectal swabs of affected dogs. Methods: The rectal swabs were collected from dogs suspected of Canine Parvovirus and subjected to PCR, Nested PCR and Realtime PCR for identification and typing of CPV in infected dogs. Results: From the study it was found that the per cent positivity was high in dogs and was found to be 50% and 89% by PCR and nested polymerase reaction respectively when considered in suspected dogs. The most prevailing antigenic type as detected by Real time PCR was found to be CPV 2a. Conclusions: The study indicated the animals vaccinated for CPV were also found positive for the disease. This study helps to detect percent positivity of CPV in dogs and also is important to identify the prevailing antigenic types of CPV in the region.

Mycobacterium tuberculosis SIT42 Infection in an Abused Dog in Southern Italy

A case of Mycobacterium tuberculosis infection is described in a dead adult male dog in Southern Italy. The carcass was found by the Health Authority in a gypsy encampment. It was admitted to our forensic veterinary medicine unit, with a suspicion of cruelty to the animal. Necropsy showed beating and traumatism signs, and mistreating was confirmed. Gross lesions included multiple nodular hepatic lesions, hemorrhagic enteritis with enlarged mesenteric lymph nodes, body cavity effusions, and an adrenal neoplasm. Bacteriological and molecular analyses were carried out on the liver lesions that enabled to identify M. tuberculosis SIT42 (LAM9). Drug-resistance patterns were evaluated by screening mutations on the rpoB and katG genes that showed susceptibility to both rifampin and isoniazid, respectively. Very few studies report canine tuberculosis, and little is known about the disease in Italy. To the authors' knowledge, this is the first report of Mycobacterium tuberculosis SIT42 infection in a dog in Italy.

Interferon-alpha-2a as a salvage treatment for hemorrhagic enteritis associated with Epstein-Barr Virus reactivation : a case report

Epstein-Barr virus [EBV] is a virus that infects almost all humans worldwide. After the acute phase of the infection, it stays in a latent form in B lymphocytes. EBV reactivation tends to occur in immunosuppressed patients. EBV reactivation may involve the gastrointestinal tract ; it has been associated mainly with colitis, but hemorrhagic enteritis has been poorly reported. Treatment usually includes antivirals. However, our patient did not respond to conventional treatment, so interferon alpha-2a was given as a salvage treatment. To our knowledge, this is the first reported case of hemorrhagic enteritis associated to EBV reactivation treated successfully with interferon alpha-2a.

INQUISITION OF CARDIOPULMONARY AND KIDNEY LESIONS PRODUCED BY NATURAL PERACUTE AND ACUTE CLOSTRIDIUM TYPE D ENTEROTOXEMIA IN CHINKARA DEER

This study describes the clinical signs, postmortem lesions and histopathological findings in chinkara deer died during an outbreak of enterotoxaemia. The study included 7 chinkara deer. During the outbreak, 5 chinkara deer died without clinical signs while 2 chinkara deer showed clinical signs before death. Clinical signs including greenish watery diarrhea, chocolate colored urine, herding in a corner with head down, fever, anorexia and opisthotonos. After death of these 7 deer, necropsy performed and observed soft and swollen kidneys, straw color fluid in abdominal cavity, edematous and congested lungs, hydrothorax, hydropericardium, hemorrhages and ballooning of small and large intestine and watery contents in the small intestine. In per-acute cases multifocal petechial hemorrhages on jejunal mucosa and myocardium were frequently observed. The histologic changes were perivascular cuffing in lungs and proteinaceous fluid in alveoli, pulmonary edema and hemorrhagic enteritis. Disruption of renal tubular epithelial cells, necrosis and congestion observed in histopathological section of kidneys. Affected deer was treated with different drugs and supplements but unfortunately prognosis was death. Enterotoxaemia is more fatal in young deer than adult. On the basis of this study we found that enterotoxaemia clinical signs, postmortem lesions and histopathological changes in deer are same as other animals such as sheep and goats.

Visual Detection of Clostridium perfringens Alpha Toxin by Combining Nanometer Microspheres with Smart Phones

Clostridium perfringens α toxin (CPA) is an important virulence factor that causes livestock hemorrhagic enteritis and food poisoning by contaminated meat products. In this study, the nano-silica microspheres combined with smartphone image processing technology was developed to realize real-time CPA detection. First, the N-terminal and C-terminal domain of the CPA toxin (CPAC3 and CPAN) and their anti-sera were prepared. The silica microspheres coupled with the antibody of CPAC3 was prepared to capture the toxin that existed in the detection sample and the fluorescent-labeled antibody of CPAN was incubated. Moreover, the fluorescent pictures of gray value were performed in a cell phone app, corresponding to toxin concentration. The new assay takes 90 min to perform and can detect CPA as little as 32.8 ng/mL. Our results showed a sensitive, stable, and convenient CPA detection system, which provides a novel detection method of native CPA in foods.

Molecular Characterization of Hemorrhagic Enteritis Virus (HEV) Obtained from Clinical Samples in Western Canada 2017–2018

Hemorrhagic enteritis virus (HEV) is an immunosuppressive adenovirus that causes an acute clinical disease characterized by hemorrhagic gastroenteritis in 4-week-old turkeys and older. Recurrent incidence of secondary infections (e.g., systemic bacterial infections, cellulitis, and elevated mortality), may be associated with the presence of field-type HEV in Canadian turkey farms. We speculate that field-type HEV and vaccine/vaccine-like strains can be differentiated through analysis of the viral genomes, hexon genes, and the specific virulence factors (e.g., ORF1, E3, and fib knob domain). Nine out of sixteen spleens obtained from cases suspected of immunosuppression by HEV were analyzed. The limited data obtained showed that: (1) field-type HEV circulates in many non-vaccinated western Canadian flocks; (2) field-type HEV circulates in vaccinated flocks with increased recurrent bacterial infections; and (3) the existence of novel point mutations in hexon, ORF1, E3, and specially fib knob domains. This is the first publication showing the circulation of wild-type HEV in HEV-vaccinated flocks in Western Canada, and the usefulness of a novel procedure that allows whole genome sequencing of HEV directly from spleens, without passaging in cell culture or passaging in vivo. Further studies focusing more samples are required to confirm our observations and investigate possible vaccination failure.