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Newcastle disease virus (NDV) is a major threat to the poultry industry worldwide, with a diversity of genotypes associated with severe economic losses in all poultry sectors. Class II genotype VII NDV are predominant in the Middle East and Asia, despite intensive vaccination programs using conventional live and inactivated NDV vaccines. In Egypt, the disease is continuously spreading, causing severe economical losses in the poultry industry. In this study; the protective efficacy of a commercial, inactivated recombinant genotype VII NDV-matched vaccine (KBNP-C4152R2L strain) against challenge with the velogenic NDV strain (Chicken/USC/Egypt/2015) was evaluated in commercial layers. Two vaccination regimes were used; live NDV genotype II (LaSota) vaccine on days 10, 18, and 120, with either the inactivated NDV genotype II regime or inactivated NDV genotype VII-matched vaccine regime on days 14, 42, and 120. The 2 regimes were challenged at the peak of egg production on week 26. Protection by the 2 regimes was evaluated after experimental infection, based on mortality rate, clinical signs, gross lesions, virus shedding, seroconversion, and egg production schedule. The results show that these 2 vaccination regimes protected commercial layer chickens against mortality, but some birds showed mild clinical signs and reduced egg production temporarily. However, the combination of live NDV genotype II and recombinant inactivated genotype VII vaccines provided better protection against virus shedding (20% and 0% vs. 60% and 40%) as assessed in tracheal swabs and (20% and 0% vs. 20% and 20%) in cloacal swabs collected at 3 and 5 D post challenge (dpc), respectively. In addition, egg production levels in birds receiving the inactivated NDV genotype VII-matched vaccine regime and in those given inactivated genotype II vaccines were 76.6, 79, 82, and 87.4% and 77.7, 72.5, 69, and 82.5% at 7, 14, 21, and 28 dpc, respectively. The results of this study indicate that recombinant genotype-matched inactivated vaccine along with a live attenuated vaccine can reduce virus shedding and improve egg production in commercial layers challenged with a velogenic genotype VII virus under field conditions. This regime may ensure a proper control strategy in layers., (Copyright © 2019. Published by Elsevier Inc.)

Tracheal swabs and different organs are collected from 17 chicken farms showing respiratory signs and variable mortalities in different governorates. Three successive blind serial passages were performed. Four IBV isolates are detected in vaccinated chickens by RT-PCR and are identified by sequence and phylogenetic analysis of portion of Si gene. Two IBV isolates, IBV S40 and IBV S61 are related to Mass reference strains (Egypt/F/03, M41, H120, Ma5, and M52). However, IBV S78 and IBV S82 are related to Egyptian variant 2 IBV strains Ck/Eg/BSU-2/2011 and Ck/Eg/ BSU-3/201 1.These results indicate the continuous evolution of Egyptian IBV circulating in chickens despite vaccination using H120 live attenuated vaccine.

Continuous circulation of influenza A(H5N1) virus among poultry in Egypt has created an epicenter in which the viruses evolve into newer subclades and continue to cause disease in humans. To detect influenza viruses in Egypt, since 2009 we have actively surveyed various regions and poultry production sectors. From August 2010 through January 2013, >11,000 swab samples were collected; 10% were positive by matrix gene reverse transcription PCR. During this period, subtype H9N2 viruses emerged, cocirculated with subtype H5N1 viruses, and frequently co-infected the same avian host. Genetic and antigenic analyses of viruses revealed that influenza A(H5N1) clade 2.2.1 viruses are dominant and that all subtype H9N2 viruses are G1-like. Cocirculation of different subtypes poses concern for potential reassortment. Avian influenza continues to threaten public and animal health in Egypt, and continuous surveillance for avian influenza virus is needed.

Objective: To evaluated the histological changes within the tegument of adult Fasciola gigantica (F. gigantica) that led to the gross changes that were visible externally., Methods: The effects of oleoresin extract of myrrh (Mirazid(®)), myrrh volatile oil and triclabendazole sulphoxide (reference drug) on the tegumental structure of adult F. gigantica following treatment in vitro had been determined by light microscopy., Results: The internal changes in the tegument observed in this study were compatible with surface changes seen in the previous scanning electron microscopy study, using the same drugs. The swelling of tegumental syncytium was a particular feature of their action, but its level was much greater with myrrh volatile oil, in which vacuolization of the tegument and loss of spines were observed., Conclusions: The present study demonstrated the fasciocidal properties of Mirazid(®) oleoresin extract, and it might be possible to reinforce its fasciocidal activity by increasing its content of myrrh volatile oil.

An outbreak of foot-and-mouth disease (FMD) in Egypt affected approximately 40,000 cattle and water buffaloes and killed more than 4,600 animals during February-March 2012. To investigate the etiology of the 2012 outbreak, specimens were collected from six governorates and analyzed using universal primers to amplify the 5' untranslated region (UTR) by reverse-transcription polymerase chain reaction. Only FMDV-SAT2 was detected, with an overall detection rate of 80.3 %. Complete VP1- and leader-proteinase-coding sequences, obtained from three isolates from three different governorates, were compared with previously reported sequences. Phylogenetic analysis of these sequences indicated that the circulating viruses were homogeneous and were closely related to topotype VII. Importantly, the newly emerged viruses were genetically closely related to strains isolated from Saudi Arabia, Sudan, Eritrea and Cameroon between 2000 and 2010, suggesting the dominant nature of this virus and underscoring the need for worldwide intensive surveillance to minimize its devastating consequences.

After emerging in Egypt in 2006, highly pathogenic avian influenza H5N1 viruses continued to cause outbreaks in Egyptian poultry and sporadic human infections. The strategy used by Egyptian authorities relied on vaccinating poultry, depopulating infected areas, and increasing awareness and biosecurity levels. Despite those efforts, H5N1 became endemic, and vaccine-escape variants are thought to have emerged even though commercial poultry vaccines were protective in laboratory settings. We studied the cross-reactivity of 6 commercially available H5 poultry vaccines against recent H5N1 Egyptian isolates in a field setting in Egypt. Only one vaccine based on an Egyptian H5N1 virus induced high cross-reactive antibody titers. Our results may be explained by the fact that the seed viruses in these vaccines are genetically distinct from H5N1 viruses currently circulating in Egypt. In light of our findings, we recommend that the H5N1 prevention and control strategy in Egypt be updated and reinforced. Special consideration should be given to the vaccination strategy, and the use of vaccines based on currently circulating viruses is advisable.

Reservoirs for the continuing influenza (H5N1) outbreaks in Egypt are ill-defined. Through active surveillance, we detected highly pathogenic influenza subtype H5 viruses in all poultry sectors; incidence was 5%. No other subtypes were found. Continued circulation of influenza (H5N1) viruses in various regions and poultry sectors perpetuates human exposure in Egypt.

Myrrh was used for controlling the infection with Eimeria species in chickens. A total of 120 one-day-old native breed chickens bought from commercial hatchery were used in the experiment. Birds were feed on starter balanced ration free from anticoccidial drugs. At age of 2 weeks the chickens were divided into 4 groups (1-4), 30 chicks each. Chickens of first group were inoculated by 50,000 sporulated oocysts of mixed local field isolated Eimneria species and served as infected non treated control group. Birds of the second group were infected similarly and received simultaneously 10 mg Myrrh / bird by oral route. Birds of group 3 was supplied with Myrrh 10 mg / bird one day before infection by coccidia (50000 oocyst/bird). Last chicken group was left as non infected non treated control group. Measurements to evaluate the efficacy of Myrrh as anticoccidial drug included; mortality percentage; lesion score at 5 day post infection and the total oocyst output/gm of fecal dropping. The results showed that the mortality rate reached 10% and 3.33% in groups 2&3 respectively, while it reached 26.66% in infected non treated control group. High lesion score was recorded in infected non treated group followed by infected treated chicken groups regardless the time of treatment. The feed conversion rates reached 3.14 in infected non treated chicken group against 2.47 & 2.21 in treated chickens groups, 2&3 respectively. Mean oocyst count per gram faecal dropping (OPG) was reduced significantly in group 3 when compared with other infected treated or infected non treated chicken groups.

The coccidicidal efficacy of volatile oils (curzerene, furanoeudesma-1, 3-diene and lindestrene) against unsporulated and sporulated chicken Eimeria species oocysts was tested in three concentrations: 1, 2 & 3 microg/ml. Marked reduction in the number of living oocysts was recorded in exposed groups. The concentration of 3 microg/ml volatile oils induced the highest destructive effect. 58.1% of viable unsporulated oocysts were destroyed. A mean number of 153,800 oocysts was the difference between the total number of the produced oocysts per gram faeces in the group infected with exposed oocysts and that of the group infected with non exposed oocysts being less in the exposed group with more reduction in the vitality of shedding oocysts in the former group. At the meantime, the postmortem and histopathological microscopical examination of the intestine and caecum of the tested group revealed a reduction in the intestinal lesions in the group infected with the exposed oocysts.

In Egypt, efforts to control highly pathogenic H5N1 avian influenza virus in poultry and in humans have failed despite increased biosecurity, quarantine, and vaccination at poultry farms. The ongoing circulation of HP H5N1 avian influenza in Egypt has caused >100 human infections and remains an unresolved threat to veterinary and public health. Here, we describe that the failure of commercially available H5 poultry vaccines in Egypt may be caused in part by the passive transfer of maternal H5N1 antibodies to chicks, inhibiting their immune response to vaccination. We propose that the induction of a protective immune response to H5N1 is suppressed for an extended period in young chickens. This issue, among others, must be resolved and additional steps must be taken before the outbreaks in Egypt can be controlled.

The highly pathogenic influenza virus H5N1 that infected chickens in Egypt in 2006 was characterized at immunologic and molecular levels. Cloacal swabs from chicken were analyzed by rapid antigen detection and RT-PCR using H5- and N1-specific primers, which confirmed the presence of an H5N1 influenza virus in infected chickens. Sequencing results revealed 100% homology of both genes with previously published sequences of H5N1 isolates from Egypt and the Middle East. The virus was isolated and propagated in MDBK cells in culture. Host cells showed a substantial cytopathic effect within 2 days of infection, which increased dramatically by the fourth day. Plaque infectivity titers of virus harvested from cell culture were initially 10(5)PFUs/ml and increased to 10(8)PFUs/ml after two additional passages and ultrafiltration. Formaldehyde treatment completely inactivated the virus, and MDBK cells inoculated with the killed virus showed no cytopathic effect. Two days after chickens were immunized with the killed virus, their sera showed that the killed Egyptian isolate was highly immunogenic. Western blot analysis showed that sera had antibodies reacting to four viral peptides: hemagglutinin (61.5kDa), RNA-binding protein (56kDa), neuraminidase (50kDa), and 45-kDa protein. In a challenge infection, the vaccine protected immunized chickens from death and reduced viral shedding.

Five concentrations of purified extract of Myrrh from Commiphora molmol tree were prepared to study its effects on the fowl tick Argas persicus under laboratory conditions. The results revealed that Myrrh had dependant dose toxic effect on the adult female of A. persicus. Toxicity increased gradually daily post treatment. The LC50 was 1.28%, 0.88%, 0.84%, 0.50% and 0.42% at Ist, 2nd, 3rd, 6th and 12th days respectively. At 12th day, the recorded mortality rates were 63, 67, 76, 87 and 94% for concentrations, 0.625, 1.25, 2.5, 5 and 10%, respectively against 5% in control. Histopathological and Transmission election microscope (TEM) examinations showed the lysing of epithelial gut cells in treated groups. The lysed epithelial gut cells showed irregularly distributed nucleus, commonly at low concentrations and rarely in high concentrations of Myrrh. The lysed epithelial gut cells, without nucleus or with aggregated one beside the basal lamina, were common at high concentrations and rare in low concentrations of Myrrh. Consequently, Myrrh can rapidly penetrate the cuticle to body cavity, destroy the epithelial gut cells and finally cause the death of ticks.