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Papers by ashraf El Dakhly

Research paper thumbnail of Demonstration of pigeon circovirus infection in Western-Libya, based on histopathology, electron microscopy and apoptosis

Research paper thumbnail of Characterization of Egyptian Isolates of Canine Distemper and Canine Parvoviruses

Journal of Applied Veterinary Sciences, 2021

Research paper thumbnail of Effect of Echinacea on antibody titres induced by Peste des Petits Ruminants (PPR) vaccine in sheep

Research paper thumbnail of Efficacy of Skimmed Milk as Stabilizer in Comparison with Lacto Albumen Sucrose in Production of Fowl and Pigeon Pox Vaccines

Aim: This work is a trail to decrease cost of vaccine production and improve the physical propert... more Aim: This work is a trail to decrease cost of vaccine production and improve the physical properties of the produced fowl pox (FPV) and pigeon pox (PPV) vaccines. Materials and methods: Two batches of live attenuated FPV and PPV were prepared. These batches were divided into 2 portion where the first portion was mixed with an equal volume of lacto albumin (5%) and sucrose (2.5%) stabilizer, while the second portion was mixed with an equal volume of skimmed milk (10 %) stabilizer. All these mixtures was subjected to freeze drying process where it was found that skimmed milk has a better physical properties than lactalbumen sucrose stabilizer, each one of the 4 dried mixtures (1FPV with lacto albumin sucrose 2FPV with skimmed milk 3PPV with lacto albumin sucrose 4PPV with skimmed milk) were subdivided into 3 portions, kept under 4, 37 and -20 c respectively. Samples were collected monthly from lyophilized vaccines kept under 4 and -20 c, while the portion which kept at 37c the sample ...

Research paper thumbnail of Efficacy of Canine Distemper and Canine Parvo Antisera to Overcome Viral Infections in Dogs

The authors have been succeeded through this work to prepare horse anti-canine distemper (CD) and... more The authors have been succeeded through this work to prepare horse anti-canine distemper (CD) and anticanine parvo (CP) hyper immune serum as a local product provided on time of request instead of the imported one which is usually unavailable and of high cost. Such antiserum was found to be free from foreign contaminants and safe inducing no abnormal local or systemic signs in inoculated animals. It was found that this antiserum had CD and CP antibody titers 512 and 1024 respectively as titrated by the Antibody Quantitate ELISA kits. These levels of antibodies were able to overcome CD in naturally infected and contact infected puppies in a percentage of 33.3 and 100% respectively. While in case of CP naturally infected and in contact infected puppies this ratio was 100% so it could be said that the prepared horse anti-CD and anti-CP hyper immune serum could be used as emergency management of CD and CP diseased puppies lowering disease progress and economic losses caused by death of ...

Research paper thumbnail of Effect of Different Stabilizers on the Stability of the Lyophilizedbovine Ephemeral Fever Virus

EC Dental Science, Jan 30, 2021

Purpose: This work aims to select the best stabilizer for lyophilization [freeze-drying] of bovin... more Purpose: This work aims to select the best stabilizer for lyophilization [freeze-drying] of bovine ephemeral fever virus [BEFV] that provide better physical appearance and high stability in different storage temperatures. Materials and Methods: Each of the four portions of live BEF virus suspension was stabilized in the ratio of 1:1 [v/v] with one of four different stabilizers 10% lactose with 2% peptone; 10% skimmed; 0.5% gelatin with 2% sorbitol and 5% lacto albumin hydro lysate with 2.5% sucrose. All these mixtures were freeze dried [lyophilized] where it was noticed that skimmed milk showed better physical appearance than other stabilizers. Each one of the 4 dried mixtures were divided into 4 portions, kept at0, 4, 37 and-20° C respectively. Samples were collected for virus titration monthly from virus samples kept under 0; 4 and-20 ° C, and every day from samples kept at 37oC. Results: After lyophilization the loss of virus titer was 0.5log10TCID50/mL using lactose and peptone, gelatin with sorbitol and lacto albumin hydro lysate and sucrose while the loss of virus titer was 0.25log10TCID50/mL using skimmed milk. The best storage temperature for all stabilized BEF virus preparation is-20oC showing any reductions in virus titer/ month intervals followed by 0oC. There is no difference on vaccinated calves' immune response to the different stabilized BEFV. Conclusion: Skimmed milk provides a better physical appearance and thermo stability than other used stabilizers.

Research paper thumbnail of Lyophilized EHV-1 vaccine inactivated and adjuvanted by Quillaja Saponaria Molina extract

Equine Herpes virus-1 (EHV-1) is one of the most common respiratory pathogens of the horses. EHV-... more Equine Herpes virus-1 (EHV-1) is one of the most common respiratory pathogens of the horses. EHV-1 induce several clinical signs of disease ranging in severity, from mild respiratory distress to abortion in pregnant mares, neonatal foal death and neuropathogenic disorders. Whole inactivated EHV-1 vaccines, which provide variable levels of protection against the disease through the induction of antibodies, have been the main type of vaccine commercially available. In order to evaluate the production of EHV-1 inactivated vaccine in lyophilized form which enhance the stability and thus the marketability of a product, this study was designed to prepare three different lyophilized vaccine formulae, inactivated and/or adjuvanted with saponin. Formula 1 contains Lyophilized EHV-1 reconstituted at time of inoculation in saponin as inactivator and adjuvant, Formula 2 contains Lyophilized EHV-1 with saponin as inactivator and adjuvant then reconstituted at time of inoculation in saline, Formu...

Research paper thumbnail of Assessment of the peste des petits ruminants (ppr) attenuated virus produced by inoculating vero cell line at different stages of cell growth

Journal of Applied Veterinary Sciences, 2016

Research paper thumbnail of Investigation of the Effect of Growth Promoting Factor Extracted from Horse Blood Platelets on the Growth Behaviour of Cell Cultures

International Journal of Scientific and Research Publications (IJSRP), 2019

Research paper thumbnail of Preparation of Lyophilized Anti-Rabies Immunoglobulin

International Journal of Innovative Research and Development, 2018

Research paper thumbnail of Preliminary Study for Preparation of Combined Attenuated Vaccine Against Sheep Pox and PPR Viruses

International Journal of Advanced Research, 2016

Research paper thumbnail of Determination of Optimal Vaccinal Dose of PPR Vaccine in Camel

International Journal of Current Research and Academic Review, 2016

Research paper thumbnail of Lyophilization as an alternative method for preservation of some continuous cell cultures

GSC Biological and Pharmaceutical Sciences, 2018

Research paper thumbnail of Protective Value of Freeze-Dried Inactivated Bovine Viral Respiratory Combined Vaccine Stabilized by Carbomer and Adjuvanted with Saponin

Advances in Animal and Veterinary Sciences

V accines need development through using new stabilizer and adjuvant to induce satisfactory immun... more V accines need development through using new stabilizer and adjuvant to induce satisfactory immunological response and to attain protection during times of challenge. Adjuvants have been used in veterinary vaccines for almost a century in trying to raise vaccine immunogenicity, chiefly by motivating innate immunity and increasing adaptive research Article Abstract | Adjuvants have been used in veterinary vaccines. Carbomer is a synthetic polymer which has a potential vast of applications in the pharmaceuticals. This work aimed to examine the immunologic effect of the carbomer as a stabilizer and adjuvanted with saponin in the lyophilized combined inactivated vaccine (Pneumo-4) instead of regular stabilizers. Freeze-dried vaccine named Pneumo-4 contained the inactivated bovine viral diarrhea virus (BVDV) genotypes, bovine herpesvirus type 1 (BoHV-1), bovine parainfluenza virus type 3 (BPI3V), and bovine respiratory syncytial virus (BRSV). The carbomer 0.3% and 0.5% were used as a stabilizer. The novel stabilizer was compared with 5% lactalbumin hydrolysate with 2.5% sucrose. The saponin solution 1mg saponin/dose was used as an adjuvant and solvent. Twelve local breed calves were utilized in the study. The calves were divided into four groups where each group contained three calves. The first two groups were vaccinated with bovine viral respiratory combined vaccine stabilized by carbomer 0.3% and 05%, respectively. The third group vaccinated with the vaccine stabilized by 5% lactalbumin hydrolysate with 2.5% sucrose. The fourth group was kept without vaccination as a test control. The poster dose was given to the calves of the first three groups 2 weeks post-vaccination. The antibody titer in vaccinated calves was evaluated by the virus neutralization test (VNT). The vaccines showed safety in calves. The immune response against the four viruses got its peak in the 4 th month post vaccination. The vaccines stabilized by carbomer showed an appropriate level of protective antibody which lasted until the 9 th month post vaccination. There was a very high significance (p≤ 0.05) between the values of neutralizing antibodies between different groups of the experiment. Finally, the use of carbomer as a stabilizer, in addition to saponin as an adjuvant, in the bovine viral respiratory combined vaccine enhances the antibody production in the immunized animals for a time of approximately 9 months. Consequently, the prepared vaccine has a significant economic impact, as it reduces the numbers of vaccination, and thus reduces the costs involved in terms of labor and tools as well as reducing the stress on animals.

Research paper thumbnail of Preparation of a Thermostable Bovine Ephemeral Fever Virus Vaccine Inactivated on the Time of Use

Egyptian Journal of Agricultural Research

he herein study was devoted to overcome the obstacles dealing with the utilization of the live at... more he herein study was devoted to overcome the obstacles dealing with the utilization of the live attenuated Bovine Ephemeral Fever (BEF) vaccine viz, the cold chain and the undesirable post-vaccinal reaction. Methylglucoside-sucrose (MS) was proved to be an excellent stabilizer for BEF thermostable vaccine. The permissible titer of the lyophilized MS-BEF thermostable vaccine was achieved even after 6 months at 25°C, 3 months at 37°C and 20 days at 45°C. The study revealed that freeze-dried MS-BEF thermostable vaccine was reconstituted with saponine (0.2µg/dose) as inactivator just at the time of inoculation. Such investigations were carried out on 4 groups of calves each was consisted of three animals. The first group animals were inoculated with the MS-BEF thermostable vaccine kept at 25°C for 6 months. The second groups were inoculated with the forementioned vaccine kept at 37°C for 3 months. The third group animals were vaccinated with BEF vaccine kept at 45 for 20 days. (The vaccine titer was 10 5.5 TCID50/ml in the three above mentioned groups), whereas the fourth group was kept as nonvaccinated normal controls. The three animal groups received booster dose at two weeks post-first vaccination. It has been deduced that such vaccine effectively induced high mean BEF neutralizing antibody titers post-boostering vaccination and protected cattle for one year. Thus, MS stabilizer was recommended for preparation of thermostable live BEF vaccine inactivated at the spot with saponine.

Research paper thumbnail of Preparation of Lyophilized Anti-Rabies Immunoglobulin

This work aims to provide anti-rabies IgG in a purified concentrated dose smaller than that of th... more This work aims to provide anti-rabies IgG in a purified concentrated dose smaller than that of the liquid anti-rabies whole serum. Such purpose was fulfilled through lyophilization of anti-rabies IgG precipitated from rabies hyper immune serum prepared in horse. Such serum was found to have an antibodies titer of 105IU/ml with immunoglobulin value of 4.3g/dl. Testing of the obtained final product revealed that it was free from foreign contaminants, safe in mice and able to stop rabies infection in experimentally infected mice. It was found that administration of IgG in mice experimentally infected with rabies virus at concentrations of 4.30, 2.20, 1.10, 0.54, 0.27 and 0.14g/dl showed protection percentage of 100; 90; 80; 80; 70 and 60% respectively when such treatment was applied from the zero time to the 3rd day post exposure. Latent treatment leads to progression of the infection where the protection rate decreased to be 40, 30, 30,20,and 10% and when administration of IgG was carried out on the 4th day post exposure to record 0% by the 6th day. Depending on these findings, it could be concluded that the lyophilized anti-rabies IgG is safe and able to withstand the virus infection when administrated on the correct time with the suitable dose.

Research paper thumbnail of Using various types of stabilizers in different Lyophilization Programs for maintenance viability of Eimeria tenella

Lyophilization (Freeze drying) technique for preservation of sporulated Eimeria tenella oocysts w... more Lyophilization (Freeze drying) technique for preservation of sporulated Eimeria tenella oocysts was applied using four lyophilization programs I, II, III and V, with three different stabilizers (lacto albumin sucrose (A), peptone (B) and skimmed milk (C) with, addition of gelatin to each stabilizers) were used for the first time in this recent study. Good and reliable results were obtained especially on using the first lyophilization program (I) in comparison with the other three programs. Lactoalbumin sucrose stabilizer (A) provided satisfied results in keeping the number of oocysts with less reduction rate post lyophilization up to 9 months. Also it retained its pathogenicity degree of Eimeria tenella.

Research paper thumbnail of Lyophilization as an alternative method for preservation of some continuous cell cultures

This work is a trial to provide lyophilization as a simple method for preservation of continuous ... more This work is a trial to provide lyophilization as a simple method for preservation of continuous cell lines instead of the freezing process in liquid nitrogen. Comparative evaluation of lyophilized African green monkey kidney (VERO), baby hamster kidney (BHK) and Madin Darby bovine kidney (MDBK) cell lines and those preserved by freezing in liquid nitrogen was carried out. Such evaluation on 6 months intervals revealed that both of lyophilized cell cultures showed delayed cell adhesion to the culture surface extending to 2-3 days post culturing while propagated and frozen cells adhered to the culture surface within few hours. However there were an increased number of adhered viable cells in case of loading of cells using trehalose and sucrose on days post culturing. In addition cultured lyophilized cells which loaded by trehalose or sucrose exhibited abnormal shape (showing cell rounding) in comparison to the other cultures. Also cell dispersing of confluent sheets of cultured lyophilized cells were found to take longer time (one hour) than that required to other cultures (few minutes) even on using EDTA and incubation at 37 C. Further studies are needed to investigate the biological behavior or cell changes which may be occurred through the lyophilization process in addition to study the susceptibility of such cells to virus infection. Depending on these facts it could be said that lyophilization is not valid for VERO, BHK and MDBK which usually used for preparation of virus vaccine in stationary or roller systems. It also could be suggested that preservation of cell lines by lyophilization may be of value in cell culturing suspension system.

Research paper thumbnail of EFFICACY OF SKIMMED MILK AS STABILIZER IN COMPARISON WITH LACTO ALBUMEN SUCROSE IN PRODUCTION OF FOWL AND PIGEON POX VACCINES

Aim: This work is a trail to decrease cost of vaccine production and improve the physical propert... more Aim: This work is a trail to decrease cost of vaccine production and improve the physical properties of the produced fowl pox (FPV) and pigeon pox (PPV) vaccines. Materials and methods: Two batches of live attenuated FPV and PPV were prepared. These batches were divided into 2 portion where the first portion was mixed with an equal volume of lacto albumin (5%) and sucrose (2.5%) stabilizer, while the second portion was mixed with an equal volume of skimmed milk (10 %) stabilizer. All these mixtures was subjected to freeze drying process where it was found that skimmed milk has a better physical properties than lactalbumen sucrose stabilizer, each one of the 4 dried mixtures (1-FPV with lacto albumin sucrose 2-FPV with skimmed milk 3-PPV with lacto albumin sucrose 4-PPV with skimmed milk) were subdivided into 3 portions, kept under 4, 37 and-20 ₒ c respectively. Samples were collected monthly from lyophilized vaccines kept under 4 and-20 ₒ c, while the portion which kept at 37 ₒ c the sample collected every day. Results: The titer of FPV and PPV samples kept at 4 ₒ c and-20 ₒ c decreased by 1.5 and 0.25log10 respectively after 6 months in case of using skimmed milk but in case of using lacto albumin sucrose the titer decreased by 2 and 0.50log10 after 6 months, the virus titer of samples collected daily at 37 ₒ c decreased by 2.25 log10 in case of using skimmed milk and 2.75 log10 in case of using lacto albumin sucrose respectively. The keeping quality test applied on the prepared vaccines showed that all of them were safe and potent. Conclusion: This study showed that skimmed milk is cheaper to FPV and PPV vaccine and provides a better in physical properties and thermo stability than lacto albumin sucrose stabilizer

Research paper thumbnail of Efficacy of Canine Distemper and Canine Parvo Antisera to Overcome Viral Infections in Dogs

The authors have been succeeded through this work to prepare horse anti-canine distemper (CD) and... more The authors have been succeeded through this work to prepare horse anti-canine distemper (CD) and anti-canine parvo (CP) hyper immune serum as a local product provided on time of request instead of the imported one which is usually unavailable and of high cost. Such antiserum was found to be free from foreign contaminants and safe inducing no abnormal local or systemic signs in inoculated animals. It was found that this antiserum had CD and CP antibody titers 512 and 1024 respectively as titrated by the Antibody Quantitate ELISA kits. These levels of antibodies were able to overcome CD in naturally infected and contact infected puppies in a percentage of 33.3 and 100% respectively. While in case of CP naturally infected and in contact infected puppies this ratio was 100% so it could be said that the prepared horse anti-CD and anti-CP hyper immune serum could be used as emergency management of CD and CP diseased puppies lowering disease progress and economic losses caused by death of these animals.This work indicated also that the Chromatographic Immunoassay as a rapid assay for detection of canine distemper (CD) and canine parvo (CP) virus antigen was less sensitive than other serological tests giving positive results of 57.1 and 54.4% of examined samples to CD and CP antigens respectively confirming the recorded disease signs on naturally infected puppies.

Research paper thumbnail of Demonstration of pigeon circovirus infection in Western-Libya, based on histopathology, electron microscopy and apoptosis

Research paper thumbnail of Characterization of Egyptian Isolates of Canine Distemper and Canine Parvoviruses

Journal of Applied Veterinary Sciences, 2021

Research paper thumbnail of Effect of Echinacea on antibody titres induced by Peste des Petits Ruminants (PPR) vaccine in sheep

Research paper thumbnail of Efficacy of Skimmed Milk as Stabilizer in Comparison with Lacto Albumen Sucrose in Production of Fowl and Pigeon Pox Vaccines

Aim: This work is a trail to decrease cost of vaccine production and improve the physical propert... more Aim: This work is a trail to decrease cost of vaccine production and improve the physical properties of the produced fowl pox (FPV) and pigeon pox (PPV) vaccines. Materials and methods: Two batches of live attenuated FPV and PPV were prepared. These batches were divided into 2 portion where the first portion was mixed with an equal volume of lacto albumin (5%) and sucrose (2.5%) stabilizer, while the second portion was mixed with an equal volume of skimmed milk (10 %) stabilizer. All these mixtures was subjected to freeze drying process where it was found that skimmed milk has a better physical properties than lactalbumen sucrose stabilizer, each one of the 4 dried mixtures (1FPV with lacto albumin sucrose 2FPV with skimmed milk 3PPV with lacto albumin sucrose 4PPV with skimmed milk) were subdivided into 3 portions, kept under 4, 37 and -20 c respectively. Samples were collected monthly from lyophilized vaccines kept under 4 and -20 c, while the portion which kept at 37c the sample ...

Research paper thumbnail of Efficacy of Canine Distemper and Canine Parvo Antisera to Overcome Viral Infections in Dogs

The authors have been succeeded through this work to prepare horse anti-canine distemper (CD) and... more The authors have been succeeded through this work to prepare horse anti-canine distemper (CD) and anticanine parvo (CP) hyper immune serum as a local product provided on time of request instead of the imported one which is usually unavailable and of high cost. Such antiserum was found to be free from foreign contaminants and safe inducing no abnormal local or systemic signs in inoculated animals. It was found that this antiserum had CD and CP antibody titers 512 and 1024 respectively as titrated by the Antibody Quantitate ELISA kits. These levels of antibodies were able to overcome CD in naturally infected and contact infected puppies in a percentage of 33.3 and 100% respectively. While in case of CP naturally infected and in contact infected puppies this ratio was 100% so it could be said that the prepared horse anti-CD and anti-CP hyper immune serum could be used as emergency management of CD and CP diseased puppies lowering disease progress and economic losses caused by death of ...

Research paper thumbnail of Effect of Different Stabilizers on the Stability of the Lyophilizedbovine Ephemeral Fever Virus

EC Dental Science, Jan 30, 2021

Purpose: This work aims to select the best stabilizer for lyophilization [freeze-drying] of bovin... more Purpose: This work aims to select the best stabilizer for lyophilization [freeze-drying] of bovine ephemeral fever virus [BEFV] that provide better physical appearance and high stability in different storage temperatures. Materials and Methods: Each of the four portions of live BEF virus suspension was stabilized in the ratio of 1:1 [v/v] with one of four different stabilizers 10% lactose with 2% peptone; 10% skimmed; 0.5% gelatin with 2% sorbitol and 5% lacto albumin hydro lysate with 2.5% sucrose. All these mixtures were freeze dried [lyophilized] where it was noticed that skimmed milk showed better physical appearance than other stabilizers. Each one of the 4 dried mixtures were divided into 4 portions, kept at0, 4, 37 and-20° C respectively. Samples were collected for virus titration monthly from virus samples kept under 0; 4 and-20 ° C, and every day from samples kept at 37oC. Results: After lyophilization the loss of virus titer was 0.5log10TCID50/mL using lactose and peptone, gelatin with sorbitol and lacto albumin hydro lysate and sucrose while the loss of virus titer was 0.25log10TCID50/mL using skimmed milk. The best storage temperature for all stabilized BEF virus preparation is-20oC showing any reductions in virus titer/ month intervals followed by 0oC. There is no difference on vaccinated calves' immune response to the different stabilized BEFV. Conclusion: Skimmed milk provides a better physical appearance and thermo stability than other used stabilizers.

Research paper thumbnail of Lyophilized EHV-1 vaccine inactivated and adjuvanted by Quillaja Saponaria Molina extract

Equine Herpes virus-1 (EHV-1) is one of the most common respiratory pathogens of the horses. EHV-... more Equine Herpes virus-1 (EHV-1) is one of the most common respiratory pathogens of the horses. EHV-1 induce several clinical signs of disease ranging in severity, from mild respiratory distress to abortion in pregnant mares, neonatal foal death and neuropathogenic disorders. Whole inactivated EHV-1 vaccines, which provide variable levels of protection against the disease through the induction of antibodies, have been the main type of vaccine commercially available. In order to evaluate the production of EHV-1 inactivated vaccine in lyophilized form which enhance the stability and thus the marketability of a product, this study was designed to prepare three different lyophilized vaccine formulae, inactivated and/or adjuvanted with saponin. Formula 1 contains Lyophilized EHV-1 reconstituted at time of inoculation in saponin as inactivator and adjuvant, Formula 2 contains Lyophilized EHV-1 with saponin as inactivator and adjuvant then reconstituted at time of inoculation in saline, Formu...

Research paper thumbnail of Assessment of the peste des petits ruminants (ppr) attenuated virus produced by inoculating vero cell line at different stages of cell growth

Journal of Applied Veterinary Sciences, 2016

Research paper thumbnail of Investigation of the Effect of Growth Promoting Factor Extracted from Horse Blood Platelets on the Growth Behaviour of Cell Cultures

International Journal of Scientific and Research Publications (IJSRP), 2019

Research paper thumbnail of Preparation of Lyophilized Anti-Rabies Immunoglobulin

International Journal of Innovative Research and Development, 2018

Research paper thumbnail of Preliminary Study for Preparation of Combined Attenuated Vaccine Against Sheep Pox and PPR Viruses

International Journal of Advanced Research, 2016

Research paper thumbnail of Determination of Optimal Vaccinal Dose of PPR Vaccine in Camel

International Journal of Current Research and Academic Review, 2016

Research paper thumbnail of Lyophilization as an alternative method for preservation of some continuous cell cultures

GSC Biological and Pharmaceutical Sciences, 2018

Research paper thumbnail of Protective Value of Freeze-Dried Inactivated Bovine Viral Respiratory Combined Vaccine Stabilized by Carbomer and Adjuvanted with Saponin

Advances in Animal and Veterinary Sciences

V accines need development through using new stabilizer and adjuvant to induce satisfactory immun... more V accines need development through using new stabilizer and adjuvant to induce satisfactory immunological response and to attain protection during times of challenge. Adjuvants have been used in veterinary vaccines for almost a century in trying to raise vaccine immunogenicity, chiefly by motivating innate immunity and increasing adaptive research Article Abstract | Adjuvants have been used in veterinary vaccines. Carbomer is a synthetic polymer which has a potential vast of applications in the pharmaceuticals. This work aimed to examine the immunologic effect of the carbomer as a stabilizer and adjuvanted with saponin in the lyophilized combined inactivated vaccine (Pneumo-4) instead of regular stabilizers. Freeze-dried vaccine named Pneumo-4 contained the inactivated bovine viral diarrhea virus (BVDV) genotypes, bovine herpesvirus type 1 (BoHV-1), bovine parainfluenza virus type 3 (BPI3V), and bovine respiratory syncytial virus (BRSV). The carbomer 0.3% and 0.5% were used as a stabilizer. The novel stabilizer was compared with 5% lactalbumin hydrolysate with 2.5% sucrose. The saponin solution 1mg saponin/dose was used as an adjuvant and solvent. Twelve local breed calves were utilized in the study. The calves were divided into four groups where each group contained three calves. The first two groups were vaccinated with bovine viral respiratory combined vaccine stabilized by carbomer 0.3% and 05%, respectively. The third group vaccinated with the vaccine stabilized by 5% lactalbumin hydrolysate with 2.5% sucrose. The fourth group was kept without vaccination as a test control. The poster dose was given to the calves of the first three groups 2 weeks post-vaccination. The antibody titer in vaccinated calves was evaluated by the virus neutralization test (VNT). The vaccines showed safety in calves. The immune response against the four viruses got its peak in the 4 th month post vaccination. The vaccines stabilized by carbomer showed an appropriate level of protective antibody which lasted until the 9 th month post vaccination. There was a very high significance (p≤ 0.05) between the values of neutralizing antibodies between different groups of the experiment. Finally, the use of carbomer as a stabilizer, in addition to saponin as an adjuvant, in the bovine viral respiratory combined vaccine enhances the antibody production in the immunized animals for a time of approximately 9 months. Consequently, the prepared vaccine has a significant economic impact, as it reduces the numbers of vaccination, and thus reduces the costs involved in terms of labor and tools as well as reducing the stress on animals.

Research paper thumbnail of Preparation of a Thermostable Bovine Ephemeral Fever Virus Vaccine Inactivated on the Time of Use

Egyptian Journal of Agricultural Research

he herein study was devoted to overcome the obstacles dealing with the utilization of the live at... more he herein study was devoted to overcome the obstacles dealing with the utilization of the live attenuated Bovine Ephemeral Fever (BEF) vaccine viz, the cold chain and the undesirable post-vaccinal reaction. Methylglucoside-sucrose (MS) was proved to be an excellent stabilizer for BEF thermostable vaccine. The permissible titer of the lyophilized MS-BEF thermostable vaccine was achieved even after 6 months at 25°C, 3 months at 37°C and 20 days at 45°C. The study revealed that freeze-dried MS-BEF thermostable vaccine was reconstituted with saponine (0.2µg/dose) as inactivator just at the time of inoculation. Such investigations were carried out on 4 groups of calves each was consisted of three animals. The first group animals were inoculated with the MS-BEF thermostable vaccine kept at 25°C for 6 months. The second groups were inoculated with the forementioned vaccine kept at 37°C for 3 months. The third group animals were vaccinated with BEF vaccine kept at 45 for 20 days. (The vaccine titer was 10 5.5 TCID50/ml in the three above mentioned groups), whereas the fourth group was kept as nonvaccinated normal controls. The three animal groups received booster dose at two weeks post-first vaccination. It has been deduced that such vaccine effectively induced high mean BEF neutralizing antibody titers post-boostering vaccination and protected cattle for one year. Thus, MS stabilizer was recommended for preparation of thermostable live BEF vaccine inactivated at the spot with saponine.

Research paper thumbnail of Preparation of Lyophilized Anti-Rabies Immunoglobulin

This work aims to provide anti-rabies IgG in a purified concentrated dose smaller than that of th... more This work aims to provide anti-rabies IgG in a purified concentrated dose smaller than that of the liquid anti-rabies whole serum. Such purpose was fulfilled through lyophilization of anti-rabies IgG precipitated from rabies hyper immune serum prepared in horse. Such serum was found to have an antibodies titer of 105IU/ml with immunoglobulin value of 4.3g/dl. Testing of the obtained final product revealed that it was free from foreign contaminants, safe in mice and able to stop rabies infection in experimentally infected mice. It was found that administration of IgG in mice experimentally infected with rabies virus at concentrations of 4.30, 2.20, 1.10, 0.54, 0.27 and 0.14g/dl showed protection percentage of 100; 90; 80; 80; 70 and 60% respectively when such treatment was applied from the zero time to the 3rd day post exposure. Latent treatment leads to progression of the infection where the protection rate decreased to be 40, 30, 30,20,and 10% and when administration of IgG was carried out on the 4th day post exposure to record 0% by the 6th day. Depending on these findings, it could be concluded that the lyophilized anti-rabies IgG is safe and able to withstand the virus infection when administrated on the correct time with the suitable dose.

Research paper thumbnail of Using various types of stabilizers in different Lyophilization Programs for maintenance viability of Eimeria tenella

Lyophilization (Freeze drying) technique for preservation of sporulated Eimeria tenella oocysts w... more Lyophilization (Freeze drying) technique for preservation of sporulated Eimeria tenella oocysts was applied using four lyophilization programs I, II, III and V, with three different stabilizers (lacto albumin sucrose (A), peptone (B) and skimmed milk (C) with, addition of gelatin to each stabilizers) were used for the first time in this recent study. Good and reliable results were obtained especially on using the first lyophilization program (I) in comparison with the other three programs. Lactoalbumin sucrose stabilizer (A) provided satisfied results in keeping the number of oocysts with less reduction rate post lyophilization up to 9 months. Also it retained its pathogenicity degree of Eimeria tenella.

Research paper thumbnail of Lyophilization as an alternative method for preservation of some continuous cell cultures

This work is a trial to provide lyophilization as a simple method for preservation of continuous ... more This work is a trial to provide lyophilization as a simple method for preservation of continuous cell lines instead of the freezing process in liquid nitrogen. Comparative evaluation of lyophilized African green monkey kidney (VERO), baby hamster kidney (BHK) and Madin Darby bovine kidney (MDBK) cell lines and those preserved by freezing in liquid nitrogen was carried out. Such evaluation on 6 months intervals revealed that both of lyophilized cell cultures showed delayed cell adhesion to the culture surface extending to 2-3 days post culturing while propagated and frozen cells adhered to the culture surface within few hours. However there were an increased number of adhered viable cells in case of loading of cells using trehalose and sucrose on days post culturing. In addition cultured lyophilized cells which loaded by trehalose or sucrose exhibited abnormal shape (showing cell rounding) in comparison to the other cultures. Also cell dispersing of confluent sheets of cultured lyophilized cells were found to take longer time (one hour) than that required to other cultures (few minutes) even on using EDTA and incubation at 37 C. Further studies are needed to investigate the biological behavior or cell changes which may be occurred through the lyophilization process in addition to study the susceptibility of such cells to virus infection. Depending on these facts it could be said that lyophilization is not valid for VERO, BHK and MDBK which usually used for preparation of virus vaccine in stationary or roller systems. It also could be suggested that preservation of cell lines by lyophilization may be of value in cell culturing suspension system.

Research paper thumbnail of EFFICACY OF SKIMMED MILK AS STABILIZER IN COMPARISON WITH LACTO ALBUMEN SUCROSE IN PRODUCTION OF FOWL AND PIGEON POX VACCINES

Aim: This work is a trail to decrease cost of vaccine production and improve the physical propert... more Aim: This work is a trail to decrease cost of vaccine production and improve the physical properties of the produced fowl pox (FPV) and pigeon pox (PPV) vaccines. Materials and methods: Two batches of live attenuated FPV and PPV were prepared. These batches were divided into 2 portion where the first portion was mixed with an equal volume of lacto albumin (5%) and sucrose (2.5%) stabilizer, while the second portion was mixed with an equal volume of skimmed milk (10 %) stabilizer. All these mixtures was subjected to freeze drying process where it was found that skimmed milk has a better physical properties than lactalbumen sucrose stabilizer, each one of the 4 dried mixtures (1-FPV with lacto albumin sucrose 2-FPV with skimmed milk 3-PPV with lacto albumin sucrose 4-PPV with skimmed milk) were subdivided into 3 portions, kept under 4, 37 and-20 ₒ c respectively. Samples were collected monthly from lyophilized vaccines kept under 4 and-20 ₒ c, while the portion which kept at 37 ₒ c the sample collected every day. Results: The titer of FPV and PPV samples kept at 4 ₒ c and-20 ₒ c decreased by 1.5 and 0.25log10 respectively after 6 months in case of using skimmed milk but in case of using lacto albumin sucrose the titer decreased by 2 and 0.50log10 after 6 months, the virus titer of samples collected daily at 37 ₒ c decreased by 2.25 log10 in case of using skimmed milk and 2.75 log10 in case of using lacto albumin sucrose respectively. The keeping quality test applied on the prepared vaccines showed that all of them were safe and potent. Conclusion: This study showed that skimmed milk is cheaper to FPV and PPV vaccine and provides a better in physical properties and thermo stability than lacto albumin sucrose stabilizer

Research paper thumbnail of Efficacy of Canine Distemper and Canine Parvo Antisera to Overcome Viral Infections in Dogs

The authors have been succeeded through this work to prepare horse anti-canine distemper (CD) and... more The authors have been succeeded through this work to prepare horse anti-canine distemper (CD) and anti-canine parvo (CP) hyper immune serum as a local product provided on time of request instead of the imported one which is usually unavailable and of high cost. Such antiserum was found to be free from foreign contaminants and safe inducing no abnormal local or systemic signs in inoculated animals. It was found that this antiserum had CD and CP antibody titers 512 and 1024 respectively as titrated by the Antibody Quantitate ELISA kits. These levels of antibodies were able to overcome CD in naturally infected and contact infected puppies in a percentage of 33.3 and 100% respectively. While in case of CP naturally infected and in contact infected puppies this ratio was 100% so it could be said that the prepared horse anti-CD and anti-CP hyper immune serum could be used as emergency management of CD and CP diseased puppies lowering disease progress and economic losses caused by death of these animals.This work indicated also that the Chromatographic Immunoassay as a rapid assay for detection of canine distemper (CD) and canine parvo (CP) virus antigen was less sensitive than other serological tests giving positive results of 57.1 and 54.4% of examined samples to CD and CP antigens respectively confirming the recorded disease signs on naturally infected puppies.