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Thermostability study of virulent Newcastle disease viruses isolated in Southern Angola
2024
António Neto | Ana M. Henriques | Teresa Fagulha | Miguel Fevereiro
Newcastle disease (ND) is endemic in Angola. Several outbreaks of ND occurred in small backyard flocks and village chickens with high mortality in the southern provinces of the country, Cunene, Namibe and Huíla, in 2016 and 2018. In those years, 15 virulent ND virus (NDV) strains were isolated and grouped within subgenotype 2 of genotype VII (subgenotype VII.2). We now present a study on the thermostability of the isolates, aiming at the selection of the most thermostable strains that, after being genetically modified to reduce their virulence, can be adapted to the production of vaccines less dependent on cold chain and more adequate to protect native chickens against ND. Heat-inactivation kinetics of haemagglutinin (Ha) activity and infectivity (I) of the isolates were determined by incubating aliquots of virus at 56 °C for different time intervals. The two isolates from Namibe province showed a decrease in infectivity of 2 log10 in ≤ 10 min, therefore belonging to the I-phenotype, but while the NB1 isolate from 2016 maintained the Ha activity up to 30 min and was classified as thermostable virus (I−Ha+), the Ha activity of the 2018 NB2 isolate decreased by 2 log2 in 30 min, being classified as a thermolabile virus (I−Ha−). Of the 13 NDV isolates from Huíla province, 10 isolates were classified as thermostable, eight with phenotype I+Ha+ and 2 with phenotype I−Ha+. The other three isolates from this province were classified as thermolabile viruses (I−Ha−). Contribution: This study will contribute to the control and/or eradication of Newcastle disease virus in Angola. The thermostable viral strains isolated from chickens in the country can be genetically manipulated by reverse genetic technology in order to reduce their virulence and use them as a vaccine in the remote areas of Angola.
Mostrar más [+] Menos [-]Olfactory epithelium organization of the grass carp (Ctenopharyngodon idella) at the ultrastructural level: SEM and TEM observations
2024
Eman H. Elsheikh | Sahar S. Hassan | Sheren A. Al-Zahaby
Olfaction is the major sense of smell in teleost involved in many physiological response and habitat acclimatization including food searching, migration for spawning, predator avoidance, reproduction behavior, as well as identification of fish of the same species. Our study illustrates the ultrastructure of the olfactory rosette of the grass carp Ctenopharyngodon idella (Cuvier and Valenciennes, 1844) by using Scanning Electron Microscope (SEM) and transmission Electron Microscope (TEM). Herein, the peripheral olfactory organs are represented by two olfactory rosettes lying in two nasal chambers, one on each side of fish snout. Each nasal chambers opens to the exterior by two nostrils a narrow inlet and wider outlet, segregated by a somewhat elevated, nasal bridge. The two nostrils are somewhat faraway as far as length of rosette’s length to permit entering and leave water flow bearing odorant molecules to the nasal cavities. The SEM revealed that each olfactory rosette is elongated oval-shaped and made up of 48-50 foliar lamellae transversely arranged on both sides of a narrow median raphe. Alongside, the magnitude of lamellae differs in relation to their location on the raphe, since the larger are in the middle whereas their dimensions gradually reduced towards both ends of the rosette indicating that the number and magnitude of lamellae increase as the fish grow. Moreover, the lamellar surface comprises sensory and non-sensory areas concealed in a mucous layer and not distributed uniformly within the epithelial surface of the olfactory lamellae. Accordingly, The TEM observations indicated that the sensory areas holds four main receptor neurons, two  are major including ciliated and microvillous receptor cells bearing either cilia or microvilli, respectively emitted from a dendritic knob. Additionally, two other minor rod-tipped and crypt cells bearing a compound rod cilium, or few microvilli and occult cilia emitted also from dendritic knob were rarely observed. From the other side, the non-sensory area comprises cylindrical flat top surface; ciliated non-sensory cells with motile long kinocilium and nonciliated stratified epithelial cells with fingerprint-like microridges both are mainly of supporting in addition of and ovoid goblet mucous cells in-between and stem basal cells. Collectively, our study revealed the general organization and ultrastructure of an important economic teleost fish that affects feeding habitat and has an important influence on the fish food intake.
Mostrar más [+] Menos [-]Potency of a combined Peste des petits ruminants and sheep pox freeze dried vaccine
2024
Mohamed A. Saad | Magda A. Kalad | Afaf A. Abd El Wahab | Amira A. El Saied | Mohamed M. Youssef | Mohamed H. Kafafy | Dalia A.M. Abdel-Moety | Namaa A. Mohamed | Mohamed H. Khodeir
           Pest des petits ruminants (PPR) and sheep pox (SP) viruses represent a hazard facing the sheep population. The present work dealt with the preparation of a combined live attenuated vaccine that protects sheep against the two diseases. Successfully, combined Peste des petits ruminants and sheep pox freeze-dried vaccine was proven to sterile and be free from different aerobic and anaerobic bacteria, fungi, and mycoplasma contaminants; safe (as no atypical reaction either local or systemic in mice and sheep and did not affect close contact unvaccinated sheep) and potent (providing vaccinated sheep with high protective specific immunity against both causative viruses) for 6 months (the experimental period) suggesting that such immunity will remain to not less than one year. It could be recommended the use of such a vaccine to control the two diseases using one shot of vaccination saves time, effort, and cost.Â
Mostrar más [+] Menos [-]Isolation and genetic diversity of fowlpox virus circulating in chicken flocks in Egypt
2024
Neven M. Ramzy | Ayatollah I. Ibrahim | Mohamed S. Abd el hafez | Eman A. Shosha
FowlPox virus (FPV) was detected in eight chickens suffering from a diphtheritic lesion on the oropharynx and trachea with nodular skin lesions around the unfeathered parts in two Egyptian governorates (El-Sharkia and Ismailia governorates) during summer 2023. A variety of serological and molecular methods were performed for identification and characterization of the virus. on specific-pathogen free (SPF) embryonated chicken eggs via chorio-allantoic membranes (CAM), the distinguishing focal pock lesions were detected on CAM. Concerning electron microscopy, FPV appeared as enveloped quadrangular brick shaped Avipoxvirions. The neutralizing antibodies level against FPV were detected in all eight samples. Serum neutralization test showed a neutralization index of ≥ 1.6 in all serum samples, meanwhile ELISA test displayed an S/P ratio of ≥ 1.5 in the affected chickens. Notably, two positive FPV samples were sequenced then submitted to the GenBank (Sharquia-1 and Ismilia-2 with accession numbers; OR920788-OR920789). The phylogenetic tree construction based on the fpv167- (P4b) gene of FPV revealed high nucleotide identity with Elsharqyia_FWPV1, Elsharqyia_FWPV2 and Fowlpox-AN5, FWPVN, FWPVD (Egyptian isolates) with nucleotide identity percentage 100%, 99%, 100%, 99%,99%; respectively. Likewise, FPV isolates were of low homology with VSVRI-Vac (vaccinal strain) with 88% similarity. In context, the local recent our strains can be applied in vaccine production for appropriate vaccination programs in Egypt.
Mostrar más [+] Menos [-]Effect of whey protein isolate on keeping quality and shelf life of minced meat
2024
Asmaa Abd Elaziz | Nabil Baker | Hossam Ibrahim | Eman Ali
Minced meat is a widely consumed and popular meat product, known for its high nutritional value. However, it is prone to contamination by a multitude of microorganisms. Therefore, the aim of this work was to improve the keeping quality and safety of chilled minced meat by using whey protein isolate (WPI) at different concentrations 1, 3, and 5% to assess their effect on the sensory attributes, chemical parameters (pH, total volatile nitrogen, thiobarbituric acid and amino acid content), and bacteriological status including total bacterial count, enterobacteriaceae count, coliform count, and staphylococcal count in minced meat stored at 4°C for 12 days, in addition, detection of some staphylococcal enterotoxins. The results showed that adding different concentrations of WPI improved the treated minced meat samples sensory qualities when compared to the control samples. WPI also improved the chilled minced meat's chemical properties by lowering pH, total volatile nitrogen, and thiobarbituric acid values while raising the amount of essential amino acids when compared to the control group. Furthermore, WPI significantly reduced the bacterial counts. Among the different concentrations tested, 5% of WPI exhibited the most significant improvement in terms of sensory, chemical, and bacterial quality, surpassing the effects observed with 1% and 3% concentrations. Incidence of Staph. aureus in the control group and the minced meat treated with 1% and 3% WPI was 60%, 20%, and 20% respectively. However, no Staph. aureus was isolated from the treated samples with 5% WPI. In control samples, enterotoxins A, A+C, and A+D were detected in 20% of each of the examined samples, respectively; enterotoxin D was detected in 20% of sample treated with 3% WPI; enterotoxin A+C was detected in 20% of sample treated with 1% WPI. The study concluded that utilizing WPI as a natural antioxidant and antibacterial preservative for refrigerated minced meat can extend its shelf life up to 12 days, in contrast to the control group, which spoiled completely within 6 days of chilled storage.
Mostrar más [+] Menos [-]Effect of silica nanoparticles on kidney of albino rats with the potential ameliorative efficacy of liposomal curcumin
2024
Hala Youssef | Yasmine A. Mansour | Ebtihal M.M. EL-Leithy | Mona K. Galal | Maha M. Rashad | Emad Tolba | Khaled S. Abou-El-Sherbini | Mamdouh A. El-Shammaa
Silica nanoparticles (SiO2-NPs) are widely used commercially in various biomedical and industrial applications. However, their potential toxicity on human and animal health hasattracted particular attention. Liposomal curcumin (LP-Cur) has effective antioxidant and anti-inflammatory defense mechanism.So, this study was achieved toassess the potential ameliorative effect of (LP-Cur) on (SiO2-NPs) induced nephrotoxicity in rats. Twenty four adult male albino rats of the same weight were divided into four groups: (Gp I) negative control group (received single intraperitoneal injection of 0.9% saline, standard diet and distilled water), (Gp II) SiO2-NPs exposed group (received 200 mg/kg body weight intraperitoneally), (Gp III) SiO2-NPs and LP-Cur co-treated group (received 200 mg/kg body weight SiO2-NPsintraperitoneally + 80 mg/kg body weight LP-Cur orally), and (Gp IV) LP-Cur treated group (received 80 mg/kg body weight orally) for 30 days. At the end of experiment, the rats were euthanized by inhalation of 2% isoflurane (0.10 ml) in internal volume of chamber. Blood and kidney samples were collected from all rats for biochemical, histopathological and immunohistochemical analyses. SiO2-NPssignificantly increased blood urea nitrogen (BUN), serum creatinine levels and malondialdehyde. Whereas they substantially reduced the glutathione levels. SiO2-NPs also caused dilatation, congestion ofmost glomeruli in addition to, some atrophied ones. Also, most renal tubulesshowed degenerative changes and marked interstitial hemorrhage. A significant increase in the immunoreactions of caspase-3 of SiO2-NPs exposed rats. Conversely, the administration of LP-Cur ameliorated the detrimental toxic effects caused by SiO2-NPs.In conclusion, antiapoptotic and antioxidant actions of LP-Cur ameliorate the nephrotoxic effect induced by SiO2-NP.
Mostrar más [+] Menos [-]Enhanced hepatotoxicity after furan and cadmium co-exposure in rats: Involvement of oxidative stress and apoptotic cascades
2024
Shrouk Amer | Ragab Elshawarby | Nabila M. Abdelaleem | Elham Elshewy | Afaf Abdelkader | Ahmed B. Zaid | Ahmed Abdeen
Furan (FU) and Cadmium (Cd) are toxic agents, and persistent exposure may harm both human and animal health. Therefore, we explored the effects of FU and Cd on liver of the male rat. Male Wister rat groups are distributed randomly: control group (Cr-water): rats were given DI water; control oil group (Cr-oil): rats received corn oil; Furan group: rats received Furan (FU, 16 mg/kg) orally; Cd group: rats obtain cadmium (Cd, 2 mg/kg) orally; and FU+Cd group: rats given both FU +Cd. For 30 days, each therapy was administered once daily. Blood samples and hepatic tissues were obtained after all rats were euthanized. The outcomes showed that treatment with FU or Cd alone considerably caused liver damage, evidenced by serum increase of AST, ALT, ALP, triglycerides, and cholesterol as well as histological changes. Following FU or Cd exposure, there were significant reductions in CAT, GSH, and SOD contents, as well as increases in malondialdehyde along with upregulated expression of PCNA and TNF-α. In contrast, when FU and Cd were administered together potentiated each other and caused more cellular damage in liver tissue. This study found that the primary modulator for enhancing FU and Cd toxicity when administered together was thought to be oxidative stress pathways.
Mostrar más [+] Menos [-]Evaluation of Moringa (Moringa Oleifera) leaves meal as a growth promoter and immune stimulant for Nile Tilapia (Oreochromis niloticus)
2024
Mostafa I. Abd El-Rahim | Abdelhakeem I. El-Murr | Ali A. Rashwan | Alaa M. Sheref
One hundred and eighty Nile Tilapia fish (Oreochromis niloticus) with initial body weight (IBW) 28 ± 0.33 grams were used in the present experiment. The experiment was conducted in glass aquariums. Fish were stocked at a rate of 15 fish in each aquarium. Fish were allocated into four experimental groups (Each group includes three replicates) and one of them was used as a control. The control group was fed on a basal diet free from moringa leaves meal (MLM), whereas 2 nd, 3 rd and the 4 th group were fed on diets containing 3.0, 4.4 and 7.4 % MLM, in replacement of 10, 15 and 25 % of soybean meal (SBM), respectively (according to the percentage of crude protein in each). The experimental period lasted for 6 weeks (42 days). Parameters of growth efficiency, blood haematology, immune response, antioxidant status and histopathological changes in internal organs of Nile tilapia were used as indices for the study. The obtained results showed that MLM have high nutritive value. Inclusion of MLM in the fish diet at level 3.0 % or 4.4 %, significantly (P < 0.5) enhanced the growth performance indices of fish, including final live body weight, body weight gain, feed conversion ratio, and survival rate (%) either after three or six weeks of feeding MLM diets compared with those fed the control diet. Fish fed 7.4 % MLM diet recorded the lowest growth performance traits compared with the control and those fed 3.0% or 4.4 MLM diets. The average of feed conversion ratio after 42 days; recorded:1.84, 1.58, 1.50 and 2.13 g feed per g gain, for fish groups fed the control, 3.0 %, 4.4 % and 7.4 % MLM diets, respectively. Survival rate (%) was improved with inclusion of MLM in the diet at level of 3.0 or 4.4 %, while it decreased with 7.4 % MLM diet. Significant improvement of immunity and antioxidant capacity of fish occurred with feeding MLM in the diet, where levels of IgM, lysozymes, RBCs, GPx, platelets (PLT) and nitric oxide (NO) were significantly increased (p < 0.05 or 0.01), with exception that levels of NO and GPx were decreased in blood of fish fed 7.4 % MLM. The levels of WBCs and SOD were not affected significantly by feeding the experimental diets.
Mostrar más [+] Menos [-]Ascofuranone antibiotic is a promising trypanocidal drug for nagana
2024
Keisuke Suganuma | Kennedy M. Mochabo | Judith K. Chemuliti | Kita Kiyoshi | Inoue Noboru | Shin-ichiro Kawazu
Trypanosomosis is a disease complex which affects both humans and animals in sub-Saharan Africa, transmitted by the tsetse fly and distributed within the tsetse belt of Africa. But some trypanosome species, for example, Trypanosoma brucei evansi, T. vivax, T. theileri and T. b. equiperdum are endemic outside the tsetse belt of Africa transmitted by biting flies, for example, Tabanus and Stomoxys, or venereal transmission, respectively. Trypanocidal drugs remain the principal method of animal trypanosomosis control in most African countries. However, there is a growing concern that their effectiveness may be severely curtailed by widespread drug resistance. A minimum number of six male cattle calves were recruited for the study. They were randomly grouped into two (T. vivax and T. congolense groups) of three calves each. One calf per group served as a control while two calves were treatment group. They were inoculated with 105 cells/mL parasites in phosphate buffered solution (PBS) in 2 mL. When parasitaemia reached 1 × 107.8 cells/mL trypanosomes per mL in calves, treatment was instituted with 20 mL (25 mg/kg in 100 kg calf) ascofuranone (AF) for treatment calves, while the control ones were administered a placebo (20 mL PBS) intramuscularly. This study revealed that T. vivax was successfully cleared by AF but the T. congolense group was not cleared effectively. Contribution: There is an urgent need to develop new drugs which this study sought to address. It is suggested that the AF compound can be developed further to be a sanative drug for T. vivax in non-tsetse infested areas like South Americas.
Mostrar más [+] Menos [-]Genetic and phenotypic impacts of calf gender on productive and reproductive traits in Friesian cattle under Egyptian farm conditions
2024
Shereen K. Genena | Mohamed H. ElSawy
This study was implemented to evaluate utilizing sexed semen that favors female births for enhancing milk production and herd replacements. 4913 calf records from 1047 Friesian cows between 1975 and 2020 at Sakha Farm were analyzed to estimate the impacts of calf gender and some environmental factors on the productive traits: lactation period (LP), total (TMY) and 305-day (305MY) milk yields and reproductive traits: age at first calving (AFC); gestation length (GL); days open (DO) and calving interval (CI). Fixed effects were parity; calving year and season (SC). Genetic (rg) and phenotypic (rp) correlations were estimated using BLUPF90 software. Results showed highly significant effects (P<0.001) of the fixed factors on all studied traits, except SC (P< 0.05) on LP and TMY, (P< 0.01) on 305MY and DO, but non-significant effects on reproductive traits. Calf gender presented strongly meaningful effects (P<0.001) regarding CI plus (P<0.05) for other traits, except AFC and genders on DO. Moderate positive rg estimates were found from 0.29 to 0.32 for female births with productive traits; weak values were found with reproductive traits, except 0.14 with GL. The corresponding rp estimates ranged from 0.26 to 0.36 with productive traits; from 0.11 to 0.19 with reproductive traits, except for weak values with DO and CI. It can be strongly encouraged to alter calf gender in females to diminish the generation interval, maximize milk production, and increase the genetic superiority of replacements.
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