Comparative studies of the potency of foot and mouth disease virus trivalent vaccine with different concentration of the antigenic content [146S]

Estimation of antigenic content [146S] of FMDV serotypes [A, O, SAT2] by sucrose density gradient [SDG] ultracentrifugation by determining the absorbance at 254 nm using ISCO520C density gradient system to produce a highly potent trivalent virus vaccine. The antigenic mass 146S [microg/ml] of serotype [O Pan Asia2, A Iran O5 and SAT2/EGY/2012] were 6.5, 6.2 and 5.9, respectively. The vaccine was injected into three groups of calves [2individuals/each group] subcutaneously in lateral part of the neck for a dose 3 ml [6.2 microg/serotype/ml], a dose 1.5 ml [4.1 microg/serotype/ml] and a dose 1 ml [2 micro/ml], the sera samples were collected at 7[th] day post vaccination [dpv], 14[th] dpv, 21[th] dpv, 28[th] dpv and every 2 wks till 40 weeks to evaluate the immune response along that period. The antibody titers/40wpv for a 3 ml dose [6.2 microg/ml] of serotypes [O Pan Asia-2, A Iran O5 and SAT-2/EGY/2012] were 2.08, 2 and 1.94, respectively [over the protective titer, PT=1.5 in SNT for cattle], a dose [4.1 microg/ml] of the three serotypes were 1.56, 1.62 and 1.63 [over PT], respectively, but for [2 microg/ml] dose of the three serotypes, the antibodies titer were 1.25, 1.19 and 1.2 [below PT], that show the antibodies titer depend on the concentration of the antigenic mass [146S] and with increase of the 146S concentration increase of the potency of the vaccine. The potency testing of the study depend upon the correlation between 146S and the neutralizing antibody titers were measured by SNT which are the perfect alternative of other potency tests which employ the challenge of the cattle with virulent virus. The immune response of the highly potent vaccine [4.1 microg/serotype/ml and 6.2 microg/serotype/ml] started early after 1[st] wpv and the protective titer remain for more than 38 wpv [especially in 6.2 microg/ml injected calves] and that confer the potency of the vaccine of that dose

Laboratory differentiation between streptococcus species isolated from different sources

This study was planned to throw light on the most important Streptococcus bacteria that isolated from the milk and pus and the most important laboratory tests that used in differentiation between the streptococcal bacterial species. This study was carried-out on a total number of 100 random samples of milk which were collected from different areas at Behera Governorate. Also. 100 pus samples from closed abscesses from different parts of cattle body where collected and examined bacteriologically for streptococcus introduction. Our results concluded that, the streptococcus agalactiae and streptococcus pyogenes are the most important bacterial isolates that causes severe losses to milk industry, also the streptococcus pyogenes of zoonotic importance as it transmitted to human. The catalase test, oxidatse test and heinolytic test are the main tests used for diagnosis and differentiation between streptococcus agaiactiae and streptococcus pyogenes. The bacitracin sensitivity test is main test for differentiation between streptococcus agalactiae and streptococcus pyogenes The results also indicated that the level of streptococcus agalactiae in milk higher than that of streptococcus pyogenes and reached to 7% and 3% for streptococcus agalctiae and pyogenes, while, in pus its levels reached to 0 and 40% for streptococcus agalactiae and pyogenes in pus. Also the results cleared that the PCR method for detection of mastitis considered as the best method

Molecular epidemiology of FMDV in northern Egypt [2012-2014]

From 2012 to 2014, foot-and-mouth disease outbreaks have struck cattle and buffaloes in different localities of Egypt exerting sever economic losses to livestock industries. Thirty-five representative specimens [thirty-one tongue epithelium and four vesicular fluid samples] were collected from different governorates [Behera, Kafrel-sheikh and Alexandria]. By using Antigen detection ELISA on these specimens revealed that twinty-six of them were positive and serotyped as [two samples were detected as serotype A, eleven samples were serotype SAT2 and thirteen samples were serotype O that was responsible for outbreaks during end of 2013 and beginning of 2014 in the three governorates] then the viral suspension cultivated on BHK-21 cell lines and obtaining on five isolates and these isolates identified as FMDV by using Real time RT-PCR using universal probe of FMDV and then serotyped by RT-PCR using Serotype-specific primers into [one isolate of serotype A, one of serotype SAT2 and three of serotype O] followed by sequencing and phylogenetic analysis revealing that the isolate of serotype A was closely related to [type A - EGY 1/2012-KC440882 with identity 93%, type A - A/IRQ/24/2009-KF112909 with identity 93% and type A isolate A/SIN/PAK/L758/2009] that of Asia topotype with Iran05 lineage that differ phylogenetically from vaccinal strain [A/EGY/2006] of Africa topotype with G-VII[KEN-05] lineage, the isolate of serotype O was closely related to [type O isolate SUD/8/2008 with identity 93%, type O isolate SUD/12/2004 with identity 92% and type O isolate O/Denizli/TUR/441/11/03 with identity 89%] that of East Africa-3 [EA-3] topotype that not detected in Egypt before and differ phylogenetically from vaccinal [O/EGY/93] of ME-SA topotype with Sharqia-72 lineage confirming that it is introduced through uncontrolled transboundary movements of animals and isolate of serotype SAT2 was closely related to [type SAT 2 isolate EGY/9/2012 and type SAT 2 isolate EGY 3/2012] of topotype VII with Ghb-12 lineage which distinct from contemporary SAT2 lineage of the same topotype of libya indicating that the disease source not through un controlled boundaries. The present study conclude and recommend that these new isolates especially O/SUD origin should be included in the locally produced vaccines to induce complete protection against circulating viruses

Molecular characterization of the avian influenza virus in Egypt

Epidemiological studies on AI virus in different governorates in Egypt [Alexandria, Bohera, Gharbia, Kafr El Sheikh, Fayoum and Menofia] during 2007 to 2009 were carried out. These studies included broiler, layer and breeder flocks in addition to duck flocks and pigeon samples. Using the RT-PCR and Chromatography test, the data revealed the following: A total of 29 out of 59, 5 out of 11 and 2 out of 5 broiler, layer and breeder examined flocks were positive with a percentage of 49.2%, 45.5% and 40% respectively. Regard to duck flocks, 10 examined flocks were negative but 2 birds out of 82 pigeon samples were positive with a percentage of 2.4%. The data clearly indicated that the highest outbreaks with AI virus were recorded in broiler flocks followed by layer and breeder flocks, then pigeon samples. The data also, indicated that the chromatography test is a highly sensitive test used for detection of the avian influenza virus. The phylogenetic analysis of the full length genome sequences of the eight viral segments from virus isolates from chicken revealed that the clustering of our samples was within clade 2.2. The isolates had the multiple basic sequences in the heamagglutinin gene at cleavage site indicating a highly pathogenic phenotype. Sequence analysis of the eight gene segments showed nucleotide as well as amino acid substitutions