Contagious Ecthyma Research Articles

Skin disease in goats (Capra aegagrus hircus): a retrospective study of 358 cases at a university veterinary teaching hospital (1988-2020).

Goats are important worldwide as a source of milk, meat, fibre and hide, and as show animals and pets. To document the type, signalment associations and prevalence of skin disease in a referral hospital population. Case population at a university veterinary teaching hospital. Retrospective study by searching computerised medical records of goats seen between 1 January 1988 and 1 January 2021. Key words employed were "alopecia, caseous lymphadenitis, Chorioptes, dermatitis, dermatophyte, dermatophytosis, goat, lice, louse, mange, mite, pemphigus foliaceus, Psoroptes, ringworm, seborrhea, skin" RESULTS: Of 1,488 records reviewed, 358 (24%) goats had skin disease recorded. Seventy-nine (22.1%) of 358 goats presented primarily for skin disease. The Nigerian Dwarf goat breed was at higher risk of developing skin disease (P < 0.0002). As goats aged, the odds for developing skin disease was higher [odds ratio (OR) = 1.07 per year, 95% confidence interval (1.04, 1.12)] as was the predilection for malignant skin tumours (P < 0.001). Sex was not associated with skin disease (P = 0.98). The most common clinical sign was exfoliative dermatitis, noted in 94 (26.4%) of 358 goats. The most common diagnoses were pediculosis, bacterial skin disease and squamous cell carcinoma. Less frequent diagnoses were Chorioptes spp. infestation, contagious ecthyma (orf), coronitis/interdigital dermatitis, demodicosis, dermatophytosis, Psoroptes spp. infestation, dermatophilosis and pemphigus foliaceus. Skin diseases are common in goats. Nigerian Dwarf goats and older goats are at greater risk of developing skin disease; Nigerian Dwarf goats had a predilection for malignant skin tumours. Clinicians should include a dermatological examination in goats regardless of the reason for presentation.

Immunomodulatory Strategies for Parapoxvirus: Current Status and Future Approaches for the Development of Vaccines against Orf Virus Infection.

Orf virus (ORFV), the prototype species of the parapoxvirus genus, is the causative agent of contagious ecthyma, an extremely devastating skin disease of sheep, goats, and humans that causes enormous economic losses in livestock production. ORFV is known for its ability to repeatedly infect both previously infected and vaccinated sheep due to several immunomodulatory genes encoded by the virus that temporarily suppress host immunity. Therefore, the development of novel, safe and effective vaccines against ORFV infection is an important priority. Although, the commercially licensed live-attenuated vaccines have provided partial protection against ORFV infections, the attenuated viruses have been associated with major safety concerns. In addition to safety issues, the persistent reinfection of vaccinated animals warrants the need to investigate several factors that may affect vaccine efficacy. Perhaps, the reason for the failure of the vaccine is due to the long-term adaptation of the virus in tissue culture. In recent years, the development of vaccines against ORFV infection has achieved great success due to technological advances in recombinant DNA technologies, which have opened a pathway for the development of vaccine candidates that elicit robust immunity. In this review, we present current knowledge on immune responses elicited by ORFV, with particular attention to the effects of the viral immunomodulators on the host immune system. We also discuss the implications of strain variation for the development of rational vaccines. Finally, the review will also aim to demonstrate future strategies for the development of safe and efficient vaccines against ORFV infections.

Detection of contagious ovine ecthyma (orf) and risk factors for infection in small ruminants in Iran

The primary cause of contagious ecthyma is the orf virus, the parapoxvirus prototype. It is a viral problem observed in goat and sheep flocks in Iran, causing economic loss. Orf is a zoonosis with little epidemiological investigation present in Iran. The current research aims at determining the status of this virus, and a PCR was used as a confirmatory instrument. We sampled 668 goats and sheep and various breeding systems. Besides, the orf prevalence was studied, and vaccination efficacy was determined. Moreover, the potential risk factors surveyed for infection with ecthyma were identified. Samples were taken from goat and sheep flocks in the present cross-sectional research, and PCR was used for testing orf DNA. A checklist including animals’ general information was completed. Data were analyzed using univariate tests (chi-square and t-tests) and multivariable binary logistic regression analysis. Three hundred one (45%) goats and sheep detected orf DNA. The age of 70% of positive cases was below one month. Ecthyma infection was significantly higher in imported breeds (87.3%) than indigenous (39.3%). Ninety-six percent of infected goats and sheep in the present work were not vaccinated against ecthyma. The high prevalence of the orf virus was confirmed among goat and sheep flocks in Iran. It is necessary to train ranchers regarding sanitary actions, quarantine, and application of orf vaccination plans.

Study on the Role of the Common House Fly, Musca domestica, in the Spread of ORF Virus (Poxviridae) DNA under Laboratory Conditions.

ORF virus (Poxviridae) is the causative agent of contagious ecthyma (soremouth), a disease primarily affecting sheep and goats worldwide, but also humans exposed to disease-ridden animals. Pathogens are shed with scabs, and infection mainly occurs by direct contact. Although the disease is relatively benign and self-limiting, the morbidity rate is high in livestock with subsequent significant financial and economic impact. The aim of the study was to experimentally investigate the potential for the housefly, Musca domestica, to act as a mechanical vector of the virus. Homogenate of crusted scabs from ORFV-positive sheep (Italy, Apulia) were used to infect laboratory-reared flies. Flies walking on viral mixture and flies inoculated on their wings were individually placed in Falcon tubes and the ORFV DNA was searched by PCR on tube walls; flies were fed on the same homogenized crusts and their crop and spots (vomit and feces) molecularly examined for ORF DNA at 2, 4, and 6 h. All of the flies (100%) used in the experiments were able to pick up and transmit the viral genome to contact surfaces; 60% were found ORF virus (DNA)-positive in both spots and crop. These results suggest that M. domestica could play a role as potential mechanical vector and/or reservoir in the epidemiology of the ORF virus infection. Thus, house fly management should be considered in the measures to control the disease in ovine–caprine farms.

Diagnóstico de ectima contagioso em pequenos ruminantes através da Reação em Cadeia da Polimerase em Tempo Real

The virus of contagious ecthyma (CEV), also known as orf virus (ORFV) is the etiological agent of contagious ecthyma (CE) in sheep and goat and belongs to the Parapoxvirus genus, family Poxviridae. In some cases, CE can be confused with vesicular diseases so there is need for differentiation especially because, according to the standards of the National Program for the Eradication of FMD (PNEFA), goats and sheep are not vaccinated against Foot and Mouth Disease (FMD), acting as sentinel animals. Although initial studies have demonstrated the usefulness of the polymerase chain reaction (PCR) as a diagnostic test, there are no studies involving its use on Brazilian field samples, which may be genetically distinct from previously studied samples, as described in a study of restriction sites analysis of Brazilian CE samples. This work was conducted with the goal of standardizing a PCR (qPCR) test using SYBR Green I dye for molecular diagnosis of EC in DNA extracted from lesions of affected animal or cell culture inoculated in field samples. The products were detected with qPCR dissociation curve analysis which showed a peak at 88 ºC indicating that positive samples have only one specific amplification product. All DNA samples tested (29 animals crusts and their cell cultures) were positive in the qPCR. The qPCR was able to detect the DNA of at least 10,000 times dilution corresponding to 0.056 ng of DNA. It is believed that with the additional qPCR validations reported in this study, it can be used for differential diagnosis in the health surveillance of PNEFA.

Contagious ecthyma: how serious is the disease worldwide?

Contagious ecthyma (CE) is an infectious disease of small ruminants caused by a parapoxvirus of family Poxviridae subfamily Chordopoxvirinae. The disease is obviously distinguished by an establishment of scabby lesions and ulcerative formation on less hairy areas including muzzle, ears, nostril, and sometimes on genitalia. The disease is endemic in sheep and goats. The virus is transmissible to other ruminants and is a public health concern in humans. Although the disease is known as self-limiting, it may cause a significant economic threat and financial losses due to lower productivity in livestock production. Information with regard to the risk of the disease and epidemiology in most parts of the world is underreported. This paper aims to provide relevant information about the epidemiology of CE in selected regions of Europe, South America, North America, Asia, Africa, and Australia. An in-depth comprehension of virus infection, diagnoses, and management of the disease will enable farmers, researchers, veterinarians, abattoir workers, health personnel, and border controllers to improve their measures, skills, and effectiveness toward disease prevention and control, toward reducing unnecessary economic loss among farmers. A herd health program for significant improvement in management and productivity of livestock demands a well planned extension program that ought to encourage farmers to equip themselves with adequate skills for animal healthcare.

Molecular Insights into the Genetic Variability of ORF Virus in a Mediterranean Region (Sardinia, Italy).

Orf virus (ORFV) represents the causative agent of contagious ecthyma, clinically characterized by mild papular and pustular to severe proliferative lesions, mainly occurring in sheep and goats. In order to provide hints on the evolutionary history of this virus, we carried out a study aimed to assess the genetic variation of ORFV in Sardinia that hosts a large affected small ruminant population. We also found a high worldwide mutational viral evolutionary rate, which resulted, in turn, higher than the rate we detected for the strains isolated in Sardinia. In addition, a well-supported genetic divergence was found between the viral strains isolated from sheep and those from goats, but no relevant connection was evidenced between the severity of lesions produced by ORFV and specific polymorphic patterns in the two species of hosts. Such a finding suggests that ORFV infection-related lesions are not necessarily linked to the expression of one of the three genes here analyzed and could rather be the effect of the expression of other genes or rather represents a multifactorial character.

The genetic identification of camel contagious ecthyma virus as the causative agent of contagious ecthyma in dromedary camels (Camelus dromedarius) in Qatar.

Camel contagious ecthyma is a contagious viral disease of camels caused by either Orf virus (ORFV) or camel contagious ecthyma virus (CCEV). It has been previously reported and shown to cause economic losses in some camel-rearing countries in Asia and Africa, but has not been detected in Qatar. The purpose of this study was to identify and genetically characterize the contagious ecthyma causative agent in Qatari dromedary camels between 2017 and 2018. Accordingly, we made diagnoses of camel contagious ecthyma based on the clinical signs and genetic analysis of the entire major envelop protein (B2L) gene. The sequence analysis showed that CCEV was the infecting virus, and the B2L gene sequences were highly conserved between the locally infected camels with 100% similarity with isolates from Bahrain. This is the first study reporting the detection of CCEV in Qatar. We suggest that sequencing of the CCEV genome is necessary to determine the origin and relationship of this virus with other members of the parapoxvirus genus.

Orf virus ORFV112, ORFV117 and ORFV127 contribute to ORFV IA82 virulence in sheep

The parapoxvirus orf virus (ORFV) encodes several immunomodulatory proteins (IMPs) that modulate host innate and pro-inflammatory responses to infection. Using the ORFV IA82 strain as the parental virus, recombinant viruses with individual deletions in the genes encoding the IMPs chemokine binding protein (CBP; ORFV112), inhibitor of granulocyte-monocyte colony-stimulating factor and IL-2 (GIF, ORFV117) and interleukin 10 homologue (vIL-10; ORFV127) were generated and characterized in vitro and in vivo. The replication properties of the individual gene deletion viruses in cell culture was not affected comparing with the parental virus. To investigate the effect of the individual gene deletions in ORFV infection and pathogenesis, groups of four lambs were inoculated with each virus and were monitored thereafter. Lambs inoculated with either recombinant or with the parental ORFV developed characteristic lesions of contagious ecthyma. The onset, nature and severity of the lesions in the oral commissure were similar in all inoculated groups from the onset (3 days post-inoculation [pi]) to the peak of clinical lesions (days 11–13 pi). Nonetheless, from days 11–13 pi onwards, the oral lesions in lambs inoculated with the recombinant viruses regressed faster than the lesions produced by the parental virus. Similarly, the amount of virus shed in the lesions were equivalent among lambs of all groups up to day 15 pi, yet they were significantly higher in the parental virus group from day 16–21 pi. In conclusion, individual deletion of these IMP genes from the ORFV genome resulted in slight reduction in virulence in vivo, as evidenced by a reduction in the duration of the clinical disease and virus shedding.

Evolution of humoral immunity effectors in four flocks of sheep with symptoms of contagious ecthyma, from Santău village, Romania

Contagious ecthyma or contagious pustular dermatitis is a debilitating condition located on the skin of sheep and goats, with a zoonotic character. Contagious ecthyma is a disease with economic and animal welfare implications, rarely being fatal if the host organism suffers from immunosuppression or if secondary infections occur. Similar to other members of the Poxviridae family, immunity to contagious ecthyma is mediated by both innate and adaptive immune responses. Following the invasion of the contagious ecthyma virus, immunoglobulins are mobilized that specifically bind to the contagious ecthyma virus to form immune complexes, which are then eliminated by defense system to protect tissues from damage. The level of circulating immune complexes and immunoglobulins can be quantified and can be an indicator of the stage of infection. In the present study we aimed to investigate whether there is a link between the individual characteristics (sex, age, severity of clinical signs) of sheep with orf symptoms and the evolution of circulating immune complexes and total immunoglobulins. In addition to these investigations, we aimed to follow the evolution of these immunological parameters compared to the evolution in clinically healthy animals. Investigations of the serum revealed that levels of these two parameters (total Ig and CIC), can be influenced by the individual characteristics of sheep affected by the contagious ectima and shows differences compared to clinically healthy animals.

Natural Infection of Goats with Orf (Contagious ecthyma) and Its Diagnosis

Background: The Study was intended to evaluate some common diagnostics that could supplement the clinical and histological identification of orf in goats. Methods: Samples from suspected clinical cases of orf (Contagious ecthyma) were collected from various organized and unorganized goat herds around Guwahati, Assam. Presumptive diagnosis was based on the typical signs and lesions. For confirmatory diagnosis, various molecular and immunoassays were employed for the detection of orf virus or circulating antibodies. Result: Cutaneous lesions observed included solitary to multifocal erythema, papules, vesicles, pustules and scab stages on the lips, ears, gums, tongue, udder and perineal region. No mortality was observed and the morbidity rate varied between 35-60%. Microscopic lesions in skin biopsies were typically marked by epidermal hyperplasia and ballooning degeneration of the keratinocytes along with other changes. Eosinophilic intracytoplasmic inclusion bodies were demonstrable within keratinocytes only in early papulo-vesicular stages. Dermis was infiltrated with polymorphonuclear and mononuclear cells in varying proportions. Initial screening of samples was done with PCR systems to specifically detect parapoxvirus DNA employing a semi-nested PCR targeted against the partial B2L gene (with reported primers yielding 594 bp and 235 bp amplified products) and an uniplex PCR targeting the whole B2L gene (with reported primer set to yield an amplified product of 1206 bp). Agar gel immuno-diffusion (AGID) failed to develop positive immunoprecipitation with hyperimmune serum against scab lysates; however, counter-immuno-electrophoresis (CIE) showed positive immunoprecipitation in the same samples. For rapid and in situ detection of ORFV antigen in tissues, immunofluorescent and immunoperoxidase techniques were successfully employed both on cryosections and formalin fixed skin biopsies. Immunofluorescent technique on cryosections was found to be easy, rapid and more specific. A dot-ELISA was also developed for successful confirmation of orf virus from clinical samples. For antibody detection in convalescing goats, an indirect-ELISA and a dot-ELISA was also successfully tested to demonstrate for antibody detection in convalescing goats, but protective titres later after infection was not addressed. Monoclonal antibody employed in the assays was found to be specific, sensitive and versatile for virus detection from direct clinical samples. It is contemplated that assays employing hyperimmune sera or detection of circulating antibody against orf virus may have limited diagnostic applications owing to its partial and transient humoral immunity and the inherent property of the virus to modulate and interfere with the host response and evade immune mechanisms.

Successful clinical management of contagious ecthyma (Orf) in goat: A case report

Clinical management of orf in animals is a challenging task due to as there is no specific treatment for this viral infection. Orf disease caused by a double-standard (ds) DNA virus belongs to poxviridae family. A female black goat of 1.5 years presented with the history of lameness and proliferative skin lesions around oral cavity. On clinical examination characteristics lesions and physical examination findings pointed towards contagious ecthyma. Animal was treated with Ceftriaxone (15mg/kg, IM, BID, Intacef®) for five days, meloxicam (0.5mg/kg IM, Melonex®) for 3 days. The owner was guided to a regular application of boric acid mixed with desi curd on skin lesions and honey for oral mucosal wounds, twice a day. Good personal hygiene (both veterinarian and owner) was maintained in order to avoid zoonotic transmission. Animal shown drastic improvement in the clinical condition with complete recovery from oral lesions after 30 days of treatment.

Detection and therapeutic management of contagious ecthyma (ORF) in a kid

A kid of age two and a half months was presented to Veterinary Clinical Complex (VCC), of Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana with history of skin lesions on fore head and nasal planum, along with alopecia and pruritis since one month. On physical examination, the lesion was observed to be dry and scabby in appearance. History from the animal owner revealed more number of similar cases of skin lesions in same age group of kids, suspecting it to be contagious. Skin scabs on molecular investigation revealed an Orf infection to the kid. The PCR product of 594bp size was generated. The kid was treated with broad spectrum antibiotic along with symptomatic and supportive treatment till complete clinical recovery. The animal owner was briefed about the zoonotic implications of the disease and was advised to take proper hygienic measures while handling the kids.

PSV-13 Incidence of infectious and non-infectious feet lesions and their association with carcass quality in sheep at a slaughter plant in Alberta

Abstract Infectious and non-infectious feet lesions (FL) in livestock have been associated with reduced welfare, production, carcass and meat quality. Currently, the incidence of FL in sheep and its relationship with carcass quality has not been documented in Canada. The objectives of this study were to determine 1) the incidence and type of lesions in Alberta sheep at slaughter and 2) the relationship between FL and carcass quality. A total of 4,487 sheep carcasses were assessed for FL at a slaughter plant in Alberta, Canada between October 2017 and March 2019. Approximately 300 sheep were evaluated monthly by two experienced observers who recorded common infectious (IN) and non-infectious (NIN) lesions. In addition, carcass information including hot carcass weight (HCW), and back fat thickness (BFT) were obtained from the slaughter plant records. Data were analyzed by multivariable regression models using SAS PROC GLIMMIX. Overall, FL incidence was 9.4% (7.0% having one lesion and 2.4% having more than one lesion). Infectious lesions accounted for 45.7% of all lesions [footrot (37.1%), interdigital dermatitis (7.3%), and contagious ecthyma (1.3%)], while NIN lesions accounted for 54.3% [overgrown horn (21.9%), injury (13.6%), laminitis (10.2%), and other lesions (8.6%)]. Sheep with IN had lower BFT (13.5 ± 1.32 cm, P = 0.0002) and HCW (51.5 ± 1.89 kg, P = 0.0189) than NIN (15.8 ± 1.51 cm and 54.7 ± 1.97 kg, respectively). For every 1 cm decrease in BFT and 1 kg decrease in HCW the odds of IN increased by 0.89 (P &amp;lt; 0.0001) and 0.98 (P = 0.0229), respectively. Based on our findings, foot lesions are a significant issue for the Canadian sheep industry and infectious lesions may have greater detrimental effect on carcass quality than non-infectious lesions. Further studies are necessary to understand the relationship of carcass quality and feet lesion.

Comparative analysis, distribution, and characterization of microsatellites in Orf virus genome

Genome-wide in-silico identification of microsatellites or simple sequence repeats (SSRs) in the Orf virus (ORFV), the causative agent of contagious ecthyma has been carried out to investigate the type, distribution and its potential role in the genome evolution. We have investigated eleven ORFV strains, which resulted in the presence of 1,036–1,181 microsatellites per strain. The further screening revealed the presence of 83–107 compound SSRs (cSSRs) per genome. Our analysis indicates the dinucleotide (76.9%) repeats to be the most abundant, followed by trinucleotide (17.7%), mononucleotide (4.9%), tetranucleotide (0.4%) and hexanucleotide (0.2%) repeats. The Relative Abundance (RA) and Relative Density (RD) of these SSRs varied between 7.6–8.4 and 53.0–59.5 bp/kb, respectively. While in the case of cSSRs, the RA and RD ranged from 0.6–0.8 and 12.1–17.0 bp/kb, respectively. Regression analysis of all parameters like the incident of SSRs, RA, and RD significantly correlated with the GC content. But in a case of genome size, except incident SSRs, all other parameters were non-significantly correlated. Nearly all cSSRs were composed of two microsatellites, which showed no biasedness to a particular motif. Motif duplication pattern, such as, (C)-x-(C), (TG)-x-(TG), (AT)-x-(AT), (TC)- x-(TC) and self-complementary motifs, such as (GC)-x-(CG), (TC)-x-(AG), (GT)-x-(CA) and (TC)-x-(AG) were observed in the cSSRs. Finally, in-silico polymorphism was assessed, followed by in-vitro validation using PCR analysis and sequencing. The thirteen polymorphic SSR markers developed in this study were further characterized by mapping with the sequence present in the database. The results of the present study indicate that these SSRs could be a useful tool for identification, analysis of genetic diversity, and understanding the evolutionary status of the virus.

Whole-Genome Sequence of an Orf Virus Isolate Derived from a Cell Culture Infected with Contagious Ecthyma Vaccine.

This is a draft genome of an orf virus (ORFV) vaccine strain assembled via long- and short-read hybrid assembly. ORFV is a zoonotic pathogen that affects sheep and goats. The genome of the virus contained in the vaccine was found to have high similarity (98%) to those of other published strains.

Zoonotic Pathogens of Dromedary Camels in Kenya: A Systematised Review.

Kenya is home to Africa’s third largest population of dromedary camels, and production at commercial and local levels are increasingly important. In pastoral and nomadic communities in the arid and semi-arid lands (ASALs), camels play a vital role in food security, while commercial milk production and formalized export markets are rapidly emerging as camel populations expand into non-traditional areas. Until recently, little focus was placed on camels as hosts of zoonotic disease, but the emergence of Middle Eastern respiratory coronavirus (MERS-CoV) in 2012, and the discovery of exposure to the virus in Kenyan camels, highlighted the need for further understanding of this area. This systematised review utilised a robust search strategy to assess the occurrence of camel-associated zoonoses in Kenya and to evaluate the quality of the published literature. Seventy-four studies were identified, covering sixteen pathogens, with an increasing number of good quality studies in recent years. Despite this, the area remains under-researched and there is a lack of robust, high-quality research. Trypanosome spp., Echinococcus granulosus and Brucella spp. appeared most frequently in the literature. Pathogens with the highest reported prevalence were MERS-CoV (0–100%), Echinococcus granulosa (7–60%) and Rift Valley fever virus (7–57%). Exposure to Brucella spp., Coxiella burnetii and Crimean-Congo haemorrhagic fever virus showed higher levels in camel or camel-associated vectors than other livestock species, although brucellosis was the only disease for which there was robust evidence linking camel and human exposure. Zoonotic agents with less severe human health outcomes, such as Dermatophilosus congolensis and contagious ecthyma, were also represented in the literature. This review provides an important summary of the scope and quality of current knowledge. It demonstrates that further research, and improved adherence to robust study design and reporting are essential if the zoonotic risk from camels in Kenya, and elsewhere, is to be better understood.

Contagious Ecthyma in Black Bengal crossbred goats and its therapeutic management

Banana is the most important fruit crop in India which requires the various cultivation practices. For carrying out those cultivation practices various energies are required to meet sustainable production. The main aim of this study was to find out the resource use efficiency estimation for banana production in Erode District of Tamil Nadu. Primary data was collected from 100 sample farmers using well structured interview schedule. The empirical results shows that except human labour, nitrogen, phosphorus and diesel remaining all other variables included in the model were positive and human labour, machine labour, nitrogen, potassium, FYM, plant protection chemicals, irrigation water, sucker and electricity were significant among other variables. Subsequently, increase in 1% use of inputs such as machine labour, potassium, electricity, sucker and plant protection chemicals would increase the yield of banana 0.15 per cent, 0.20 per cent, 0.02 per cent, 0.01 per cent and 0.01 per cent respectively and 79 per cent of the variations in banana yield were influenced by the explanatory variables. Likewise price fluctuation plays a major constraint among the banana farmers. This study suggested the banana farmers to use more amount of potassium and to reduce the usage of human labour and as well as nitrogen fertilizer for sustainable use of resources.

Contagious Ektima (CE) aşısının bağışıklık ve zararsızlık çalışmalarında tavşanların kullanılması

Contagious ecthyma (CE) is a zoonotic viral infection and common localized cutaneous infection of young sheep and goats caused by a Parapoxvirus with worldwide distribution. The aim of this study was to use rabbits instead of lambs and kids in immunity and safety studies after production of the CE vaccine. The titres of Pendik CE pathogen strain isolated lamb (E(P)CK4) and attenuated vaccine strain originated lamb (E(P)CK22) used in the study were TCID50 106.50 and 107.00/ml, respectively. In the study to determine the pathogenicity of CE virus (E(P)CK4) in rabbits, it was found that CE virus-specific hyperemia, vesicles and pustules were not observed and did not contain CE virus by PCR test in the scabs in the scarred back-waist regions, and body temperature did not increase in rabbits. In the blood sera of rabbits treated with pathogen CE virus and vaccinated with CE vaccine virus, no antibodies were detected against CE virus. It was found that the vesicles, pustules and scabs appeared on day 3 and the lesions healed on the 15th day. In the immunity study in lambs and kids vaccinated with CE vaccine (E(P)CK22), it was found that CE vaccine virus protects lambs and kids against pathogen CE (E(P)CK4) strain.

Adaptation of Contagious Ecthyma vaccine strain to MDBK cell culture and immunity-stability studies in lambs

Contagious ecthyma (CE) is a common viral infection in lambs and kids, and still maintains its importance in sheep and goat breeding. Attenuated, live and lyophilized CE vaccines adapted to cell culture are widely used in the fight against CE. The aim of this project was to adapt the CE vaccine strain to Madin Darby Bovine Kidney (MDBK) cell culture and to produce the vaccine, as well as determining the shelf life, stability, innocuity, and immune response in lambs. The titer of the vaccine virus adapted to the MDBK cell culture was determined to be TCID50 106.5/ml. In the innocuity study on mice and guinea pigs, no local or general reactions were observed. . Body temperature of 10 lambs vaccinated by scarification was found to be between normal values (38.2-39.1°C). Neutralizing antibodies belonging to CE virus with VNT could not be detected in blood sera taken on 30th day following the vaccination. As a result of challenge performed with pathogen (E(P)CK5) CE virus, the protection was observed against CE infection in vaccinated lambs. In the stability study, the titers of lyophilized CE vaccine were found to be TCID50 106.5/ml from 1 to 15 months and 106.0/ml at 18, 21 and 24 months during the 24-month storage period at + 4/+8°C. It was determined that the vaccine virus remained as stable at TCID50 106.5/ml titer for 12 hours at 30, 33, 37 and 40˚C and after 12 hours, the virus titer regressed to TCID50 105.75/ml. at 42°C and 45˚C. This study concluded that CE vaccines could be produced in MDBK cell cultures by adapting CE virus to MDBK cell culture.