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Detection of multidrug-resistance Staphylococcus aureus from mastitic cows' milk in Dakahlia and Damietta Governorates, Egypt
2024
Alaa Gabr | Asmaa Sadat | Gamal Younis
Staphylococcus aureus (S. aureus) is an important microbe which has the ability to cause a mastitis in cows and causes huge economic losses. This microorganism has a growing ability to resist antimicrobial agents which let to hinder the treatments programs. The study aimed to isolate and identify the prevalence of multi-drug resistant S. aureus in mastitic cows’ milk in delta region (Dakahlia and Damietta governorates). A two hundred milk samples were randomly selected from clinical mastitic and sub-clinical mastitic infected cows (one hundred from each); these infected cows farms located at Dakahlia and Damietta governorates during the period of November 2020 to March 2021. The samples were diagnosed using routine culture methods to isolate S. aureus. All suspected colonies were subjected to biochemical analysis for the basic identification of S. aureus colonies. The biochemically identified S. aureus colonies were confirmed by using molecular marker targeting thermonuclease-nuc gene by PCR. All the confirmed S. aureus isolates were subjected to antimicrobial sensitivity testing against eighteen antimicrobial agents by using Kirby–Bauer disc diffusion method. Out of the 200 tested milk sample, a forty-six were identified as S. aureus isolate revealed a total prevalence 23%. S. aureus prevalence rate in clinical mastitic and sub-clinical mastitic samples was 37 (80.4%), and 9 (19.6%), respectively. S. aureus isolates revealed a high resistant against oxacillin, ampicillin, and ceftiofur, and moderate resistance against tetracycline, amoxicillin- clavulanic acid, cefotaxime, cefuroxime, vancomycin, and gentamycin, while a high sensitivity of S. aureus was displayed against ciprofloxacin, SXT and marbofloxacin. All examined S. aureus isolates were sensitive against imipenem. Multidrug resistance (MDR) was displayed in all the isolates. Building food tracking and farm animal surveillance systems is essential to improving the healthiness processing and guaranteeing that consumers receive safe food.
显示更多 [+] 显示较少 [-]Influence of Moringa Oleifera leaf extract and synbiotic supplementation on mitigating stress of broilers subjected to high stocking density.
2024
Rasha Ragab | Abdelrahim H.A. Hassan | Hosney H. Emeash | Fatma Khalil
Environmental factors such as stocking density can cause stress and negatively affect the physiological status and meat quality of broiler chickens. In the current study, we evaluated the effects of increased rearing density on the growth performance, stress, fear levels, meat quality and liver histopathology of broilers as well as suggesting a use of different supplementations that may be helpful to reverse such adverse effects. Three hundred sixty one day-old cobb broilers (44.0 ± 5.24 g live-weights) were randomly distributed to 24 replicate pens to create two different stocking densities (D10 and D15 bird/m2) with the different supplementation treatments: 1) 10 birds/m2/pen (without any treatment, control, "CD10"), 2) 10 birds/m2/pen (moringa aqueous extract treatment "MAED10"), 3) 10 birds/m2/pen (synbiotic "SynD10"), 4)15 birds/m2/pen (without any treatment control SD15 "CD15"), 5) 15 birds/m2/pen (moringa aqueous extract treatment "MAED15"), 6) 15 birds/m2/pen (synbiotic "SynD15"). Results of the current study revealed that there was a significant increase in the overall experimental period body weight gain (P<0.01) with increasing density without affecting feed intake, body weight and feed conversion ratio. High stocking density resulted in significantly increased corticosterone (P>0.001), altered brain monoamines, deteriorated some carcass quality parameters and declined liver health. Additionally, it was concluded that moringa aqueous extract (MAE) and synbiotic (Syn) supplementation have a significant effect in reversing the catastrophic effect of high stocking density (SD) with minimal effect at the lower density groups.
显示更多 [+] 显示较少 [-]Nitrite free fresh sausage formulated with innovative nitrite alternatives and their impacts on shelf life and quality attributes during refrigerated storage
2024
Essraa Youssef | Hemmat M. Ibrahim | Mohamed A. Hassan | Hamdy A. Zahran | Rasha Elsabagh
Nitrite is a vital preservative widely used in meat processing. Carcinogenic N-nitroso compounds discovered in processed meat products became serious impacts negatively affect meat industry. The present study provided a nitrite free fresh sausage with a novel method to substitute nitrite with a mixture consisted of (400 ppm nisin+25 ppm Zinc oxide nanoparticles+ 1% Hibiscus sabdariffa extract +1% chitosan) employing nisin (N) and Zinc oxide nanoparticles (ZON) as antimicrobials, chitosan (C) as antioxidant and H. sabdariffa extract (H) for color improving. In vitro antibacterial activity of nisin and ZON against Clostridium perfringens reference strain was estimated using agar well diffusion test. H. sabdariffa extract was evaluated for its phenolic and flavonoid contents as well as its phytochemical profile was analyzed using HPLC. Four variants of fresh sausage with different treatments were prepared: Nitrite (NT) treated, (N.C.H), (ZON.C.H) and (N.ZON.C.H), packed in polyethylene bags and kept in a refrigerator at 4 ?C. Samples were examined to assess their pH, microbiological evaluation (aerobic plate, Enterobacteriaceae, yeast and mold counts), also, sensory assessment and shelf life were evaluated. Results exhibited that nisin and ZON have potent antibacterial activity against Cl. perfringens with inhibition zone of 30 mm and 15 mm compared to 30 mm of sodium nitrite. Hibiscus extract manifested a high phenolic content about 27.213 mg Gallic acid /g, 2.896 mg QE/g for flavonoids and about 19 main phenolic compounds were detected by HPLC. Results exhibited that N.ZON.C.H group samples showed the lowest pH values, APC, Enterobacteriaceae, yeast and mold counts among sausage variants. Regarding shelf life and sensory evaluation, as expected, N.ZON.C.H showed the highest sensory scores and shelf life (18 days) followed by N.C.H and ZON.C.H that remained accepted till 15th and finally NT till 12th day of cold storage. Results suggested that combination of nisin, ZON, chitosan and H. sabdariffa extract would be a promising new strategy to replace sodium nitrite and improve safety and quality of fresh sausage.
显示更多 [+] 显示较少 [-]Prospective Risk Assessment of some Heavy Metals on Tilapia zilli in Temsah Lake
2024
Amira M.H. Elsharkasy | Amal A.M. Ahmed | Mona M. Ismail | Hassnaa M. Elsheshtawy | Marwa A. Hassan
This study was conducted to determine the pollution index of some heavy metals in Temsah Lake water to assess their transfer into Tilapia zillii tissues using bioaccumulation factors as well as evaluate their associated health risks. Results showed that Pb, Cd, and Cu levels increased significantly during spring, summer, and both spring and summer, respectively. The pollution index of heavy metals in the Temsah Lake revealed that Fe had a moderate effect in winter and a strong effect in the other seasons. Pb had a serious impact on aquatic life in the spring and autumn, while Cd had a serious impact in the summer and autumn. Water temperature is strongly correlated with Cu in the liver, Pb in the musculature, and Cd in the water and liver. Conversely, it negatively correlated with fish weight, length, Fe, Zn, and Cu in the musculature. Fish length showed an inverse relationship with water Cu, Cd, Pb, and Cd. The histopathological examination revealed hydropic degeneration, fatty changes, and interstitial and focal infiltration of immunocompetent cells. Muscular tissue revealed degenerative changes manifested by atrophy and fragmentation of muscular fibers in some specimens. The bioaccumulation factor of heavy metals in Tilapia zilli musculature and liver was found to be highest during winter. Fish musculature was safe for Pb, Cd, and Cu and might represent potential risks for Fe and Zn. In conclusion, warm seasons have the highest integrated biomarker response (IBRv2) scores for the detected heavy metals, also the sum of IBRv2 of the heavy metals content is the highest in musculature followed by livers then water samples. Herein, TCR results for Pb and Cd in Tilapia zilli are within the permissible range (10−4 to 10−6).
显示更多 [+] 显示较少 [-]Ameliorative effect of a novel enzymatic detoxifier against natural field levels of mycotoxins in the broiler chicken diet
2024
Tasneem Mohamed Salama | Mohammed A.M. Kamal | Samar Helal Abdelfatah | Heba Mohamed Salem | Fathy F. Mohamed
Mycotoxins are considered hidden dangers that threaten the poultry industry globally because they suppress the immunity of birds, reduce their production, and increase their chance of being infected with diseases, which exposes the poultry industry to enormous economic losses. Therefore, this investigation aimed to assess the effectiveness of VemoZyme Detox®, a novel enzymatic detoxifier, in mitigating the detrimental consequences of mycotoxin contamination in broiler chickens. The experiment involved 10,000-day-old, Cobb 500 broiler chicks, which were allotted into two groups of 5000 birds each as follows: T1: received a control basal diet; and T2: birds were provided with a basal diet supplemented with VemoZyme Detox®. The birds underwent comprehensive monitoring, including evaluations of growth performance, blood parameters, mycotoxin levels, hepatic histopathological alterations, and litter bacteriological counts. Broilers receiving dietary VemoZyme Detox® exhibited significant improvements in various aspects, including growth performance, reduced mortality rates, and more favorable feed conversion ratios. Moreover, the enzymatic supplement played a protective role in maintaining hepatic and renal health, as evidenced by reductions in blood aspartate aminotransferase (AST), alanine aminotransferase (ALT), uric acid, and creatinine. Importantly, although there was no significant difference in mycotoxin levels (zearalenone, fumonisin B1, ochratoxin A, aflatoxin B1) within the feed, VemoZyme Detox® had a significant impact on decreasing mycotoxin levels, particularly those of zearalenone and fumonisin B1. Hepatic histological examinations also revealed healthier conditions in T2, and positive impacts extended to litter samples, as indicated by reduced counts of Clostridium perfringens (C. perfringens) and Escherichia coli (E. coli) counts. In conclusion, the use of an enzymatic detoxifier is a promising method for counteracting the negative impacts of mycotoxin contamination in broilers. The results underscore the substantial potential of enzymatic detoxifiers for ensuring the health and productivity of broilers, opening new avenues for safer poultry production.
显示更多 [+] 显示较少 [-]Molecular characterization of avian influenza viruses (H5N2, H5N8, H5Nx and H9N2) isolated from chickens and ducks in the South of Egypt 2020 – 2021
2024
Ahmed A.H. Ali | Shimaa Mansour | Sozun M. Hefeny | Serageldeen Sultan
This study was conducted to investigate the epidemiological situation of avian influenza viruses (AIV) and the molecular identification of the different AIV subtypes circulating among chickens and duck farms in South Egypt. A total of 143 samples were collected from chicken and duck farms in Qena (n = 105) and Luxor (n=38) governorates during 2020. The organs and swabs were collected from diseased chickens and healthy ducks. The viruses were isolated in embryonated chicken eggs (ECEs) and their propagation was confirmed by hemagglutination test (AHT) and molecular detection of matrix gene by reverse transcription polymerase chain reaction (RT-PCR). AIV subtypes were identified by RT-PCR and specific primers. Phylogenetic analysis of sequenced partial H5, N2, and N8 genes was performed. The results revealed that 15 AIVs were subtyped to 2 H5N2, 2 H5N8, 8 H5Nx, and 2 H9N2. While an isolate could not be subtyped by used primers. The H5-based evolutionary tree of 4 isolates revealed their categorization with the 2.3.4.4b clade with close relation to H5N8 isolates from Egypt in 2021 and Kazakhstan in 2020. In conclusion, the occurrence of H5 and H9 viruses pays attention to a public health concern. Also, non-identified HxNx reveals a new AIV HA and NA subtype may be present among chickens.
显示更多 [+] 显示较少 [-]Pathological studies on some marine fish parasites in Egypt
2024
Abdelmoneim A. Ali | Nahla A. Refat | Rehab E. Mowafy | Safaa A. Gaheen | Omar H. Amer | Manar A AbdelMageed
Marine fish is an important source of high-quality, yet relatively cheap animal protein in the Egyptian’s diet. Although most parasitic diseases might not cause direct losses of fish, it has deleterious effects on their weight gain and marketability and weaken the fish's immune system paving the way for more serious secondary infections. In this study, we recorded the most common parasitic infestations in marine fish in Egypt in the period between winter 2019 to summer 2021 and described their associated pathologic effects. Four hundred fish from seven different fish species (Mugil cephalus, Pomadasys incisus, Gilthead sea bream, Pagrus Pagrus, Morone labrax (sea bass), thunnus thynnus and Caranx crysos) were randomly collected from the Mediterranean and the Red Sea. Out of the 400 examined fish, 197 (49.25%) infestations were recorded. The isolated parasites were a crustacean, two cestodes, and a nematode and were morphologically identified as follows: Ceratothoa oestroides, Callitetrarhynchus gracilis, Tetraphyllidean larvae and Hysterothylacium deardorffoverstreetorum). Among the infested fish, the highest prevalence of infestation was recorded by Ceratothoa oestroides (43.65%) followed by Hysterothylacium deardorffoverstreetorum (31.98%) and Callitetrarhynchus gracilis (24.37%), and the lowest prevalence rate was recorded by the Tetraphyllidean larvae (15.74%). The pathologic macroscopic and microscopic lesions associated with each type of infestation are described underscoring the importance of continuous search for and application of possible safe control measures for marine fish parasites to spare the fish industry the detrimental effects of these infestations.Â
显示更多 [+] 显示较少 [-]Molecular detection of highly pathogenic avian influenza A (H5N8) virus isolated from domestic ducks and chickens in Egypt across 2018-2021
2024
Ahmed A.H. Ali | Adel M. Soliman | Gamelat k.F. Kotb | Kareem E. Sewede | Fatma M. Abdallah
The present study was carried out to describe Egyptian H5N8 viruses isolated from vaccinated duck and chicken flocks in 2018-2021 from different provinces, Egypt. This study screened 10 vaccinated farms (five duck and five chicken) suffering from respiratory & nervous signs with high mortality rate (90%). Out of ten examined flocks, six flocks were positive for avian influenza virus (AIV) by virus isolation into embryonated chicken eggs (ECEs) for third blind passages. The initially positive samples were confirmed, identified molecularly using quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) using primers targeting M gene of influenza A. RT-qPCR positive isolates were subjected to partial amplification of hemagglutinin (HA) and neuraminidase (NA) genes using RT-PCR followed by sequencing and phylogenetic analysis for six isolates representative for one duck flock and five chicken flocks. Our findings proven that four flocks only were found positive for AIV/HPAI H5N8 virus by sequencing and phylogenetic analysis for HA and NA genes. The similarity between nucleotide sequencing for the four HA and NA was 99.8% and 98.1%, respectively, with H5N8 viruses previously detected in Russia, Iran, Israel and Iraq. As well as, the phylogenic analyses, focusing on HA and NA genes indicated that Egyptian H5N8 viruses clustered in group B Russian like reassortant H5N8 viruses of clade 2.3.4.4. In conclusion, the detection of the HPAI H5N8 virus in domestic birds even in vaccinated birds is a serious threat; therefore, this is needed for periodic molecular monitoring with vaccine efficacy evaluation and annual surveillance.
显示更多 [+] 显示较少 [-]An updated investigation on the antenatal development of the thyroid gland in white New Zealand rabbit with morphometric analysis
2024
Attia A.A. Moselhy | Hamed M. Nosseur | Sahar M. El-Sayed | Mervat M.H. Konsowa
The prenatal development of the thyroid gland was studied on 30 rabbit embryos and fetuses of both sexes. Their ages ranged between 9th days old till the day of birth. The thyroid anlage appeared as an endodermal thickening in the floor of the primitive pharynx at 9th days of gestation. At 11th days old embryos, the thyroid bud was connected to the pharyngeal endoderm by the thyroglossal duct which began to disintegrate at 12th days of gestation. The bilobation of primitive thyroid gland was exhibited with the beginning of isthmus organization at 16th days of gestation. The first evidence of follicular organization appeared at 20th days of gestation with many small follicles disseminated within the gland. The first morphological sign of functional differentiation of the thyroid gland appeared at 22nd days of gestation as PAS positive thick rim of pre colloid material in apical parts of the follicular cells in some follicles. Very few parafollicular cells began to scatter among follicular cells at 22nd days old fetuses. The definitive thyroid follicles storing vacuolated typical colloid organized at 28th days of gestation and stained somewhat strongly with Eosin and PAS.
显示更多 [+] 显示较少 [-]Impact of Debaryomyces hansenii and Saccharomyces cerevisiae cell free extracts on yoghurt quality
2024
Manal M. Abdullah | Hend A. Elbarbary | Hamdi A. Mohamed | Marionette Z. Nassif
Beneficial yeast extracts mainly of Debaryomyces and Saccharomyces species, have been considered as one of the natural biological fermenters of food products. These yeast metabolites, specially their mycocins can be used to prolong storage time of yoghurt. This study was undertaken to assess the effect of mycocin (Debaryomyces hansenii (DH) and/or Saccharomyces cerevisiae (SC) cell free extracts) (CFEs) on yoghurt quality. Yoghurt samples examined for coagulation time, titratable acidity, sensory and microbiological quality at appropriate intervals until the appearance of spoilage (texture changes). The pre-heated skimmed milk was mixed with starter culture and then it was divided into 10 groups, each inoculated by different inoculum and a certain concentration of (DH) and/or (SC) CFEs (100, 200 and 400 ppm) and incubated at 42oC till curd formation, then refrigerated at 4±1oC and examined every 3 day till appearance signs of spoilage. The obtained results revealed a significant elongated coagulation time with the mycocin concentration (400 ppm). During the storage period, titratable acidity steadily rose in all groups. In addition, a significant improvement in the sensory quality parameters represented by flavor, appearance and texture characters appeared with the treated groups with mycocin concentration (100 ppm) compared with the other groups. Regarding to the total fungal count, treated groups with mycocin (400 ppm) showed the most significant inhibitory effect on fungal growth. In conclusion, DH and SC mycocins at concentration of 100 ppm could significantly extend shelf-life of treated yoghurt samples with the highest flavor and texture scores in comparing to the control and the other treated groups.
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