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The present study assessed the effects of dietary supplementation of probiotic CLOSTAT, alone or in combination with Aviboost® supplement, on growth performance, intestinal histomorphology, and immune response in broiler chickens. A total of 600 one-day-old broiler chicks were divided into three groups: G1 (non-treated negative control group), G2 (probiotic CLOSTAT®- and Aviboost®-treated group), and G3 (probiotic CLOSTAT®-treated group). Feed intake and mean body weight were measured weekly for all groups. Sera were collected for cytokine analysis, and duodenal samples were also collected for histomorphological examination. The results revealed that the mean body weight gain was significantly increased to 2.25 and 2.2 kg/bird in G2 and G3, respectively, compared to 1.95 kg/bird in G1. Similarly, the feed conversion ratio (FCR) was improved to 1.56 and 1.59 in G2 and G3, respectively, compared to 1.8 in G1. Serum interferon-γ (IFN-γ) and interleukin (IL)-6 protein concentrations were significantly increased in G2 and G3 compared to G1. Furthermore, the absorptive cells of the villi revealed structural changes, including hyperplasia and increased goblet cell population and microvilli height, in G2 and G3 compared to G1. The lamina propria of duodenal villi in G2 and G3 showed increased cellularity at 22 days of age. In conclusion, concurrent supplementation of CLOSTAT® and Aviboost® to broiler chickens slightly improved the body weight gain and FCR but did not exhibit synergistic or additive effects on intestinal morphology and systemic immune response

In this study, a Brucella antigen-capture ELISA (Ag-cELISA) prototype was developed. To study the validity of the developed Ag-cELISA, milk samples collected from Brucella-positive goats (n=120) and cattle (n= 64), as well as from unknown Brucella-status cattle (n=105) and sheep (n=65) herds were tested by Ag-cELISA, I-ELISA, and culture method. All Brucella-positive samples were confirmed using PCR. It was found that the developed Ag-cELISA could detect 50-100 bacteria per well (equivalent to 103 to 2×103 cells per mL) as the lowest limit of detection (LOD) and was therefore considered moderately sensitive to detect brucellae in milk. In an infected goat herd, out of 120 milk samples, 41, 32, and 17 were positive by Ag-cELISA, I-ELISA, and culture, respectively. Ag-cELISA detected 15 positive cases out of 17 culture-positive milk samples. Two culture-positive milk samples were not detected in Ag-cELISA. The relative sensitivity and specificity between Ag-cELISA and I-ELISA were 78% and 100%, respectively. In an infected cow herd, out of 64 milk samples, 32, 23, and 11 were found positive by Ag-cELISA, I-ELISA, and culture, respectively. Ten out of 11 culturally positive milk samples were found positive by Ag-cELISA. The relative sensitivity and specificity between the Ag-cELISA and I-ELISA were 71.9% and 100%, respectively. From randomly collected 105 cow and 110 sheep milk samples from herds of unknown Brucella-infection status, three (2.85%) and five (4.5%) samples were found positive using Ag-cELISA, respectively. These results showed that Ag-cELISA could be used to detect brucellae in milk more practically and safely than bacterial culture. On the other hand, this information re-affirms that milk can be an important source of brucellosis and creates a public health risk in humans; therefore, increased public awareness is of utmost importance

Commercial turkey production can experience an economic loss due to exposure of birds to stress. Turkeys can undergo various levels of stress, including, but not limited to, hatching, brooding/growing, and transport. Temperature, climate, heat, and cold stress are major livestock stressors associated with economic losses. Exposure to stress also causes an increased probability of infections and diseases that have a negative financial impact on production. In this study, Large White commercial turkey hens were reared for 12 weeks (wk) to evaluate their stress responses and performance alterations due to induced stress through a mimic of brooder house to grow-out transition. Parameters for performance, blood, and meat yield were recorded. Spray-dried bovine plasma (SDBP) was formulated iso-nutritionally into the diets. SDBP has been shown to be an ingredient in animal diets that may help support immune health and positively affect performance. This ingredient was used for a total of 6 wk in the starter and grower-1 diets at different inclusion percentages. Treatments included a control diet (0% SDBP), 1.0% (SDBP1), and 2.0% (SDBP2) inclusion. At 6 wk, common diets were fed (grower-2 and finisher-1). At 5 wk management-based stressors were applied for 24 hours (h): feed and water restriction and reduced house temperature. Previously used pine shavings were used for bedding. No significant variances were noted in body weight, weight gain, or feed consumption as a result of the different feed treatments. However, during the sixth week, the feed conversion ratio (FCR) was improved due to SDBP inclusion. The FCR for SDBP1 (1.90) and SDBP2 (1.97) birds was lower than that of the control diet-fed birds (2.04). No difference in FCR was observed at 12 wk. A significant difference was observed for corticosterone levels post-stress: SDBP1 (23.81 ng/mL) and SDBP2 (19.17 ng/mL) were higher than that of the control birds (16.40 ng/mL). Further research is needed to ascertain the impact of SDBP on the immune function and production of turkeys.

Escherichia coli gene mutations (plasmids, integrons, and transposons) have instigated multidrug resistance (MDR) against various antimicrobials. This study detected antibiotic-resistance genes (genotypic and phenotypic) in E. coli and performed Whole-genome sequencing to discover MDR-associated E. coli genes in mullet fish. E. coli isolates were serologically identified and their antimicrobial sensitivity was tested. E. coli presence was confirmed in 35% of the mullet fish samples. Cephalosporins, tetracyclines, and sulfonamides presented higher efficiency against E. coli. The serological investigation revealed the presence of STEC (O157:H7, 50%), ETEC (O142, 20%), EHEC (O26:H11,15%), and  EPEC (15%) in mullet meat samples. A symmetrical band represented the Subunit B of the Shiga-like toxin (SLT) genewhereas the Heat-labile toxin (LT) gene was found in plasmid and genomic DNA-detected strains. The results revealed the hazardous nature of STEC for mullet meat consumers. The study recommends improving the hygienic conditions during the mullet handling and processing steps, which will minimize  antibiotic usage and resistance.

This work studied in vitro; the antibacterial activity of Vitex agnus-castus (VAC) extract against V. anguillarum, its minimal inhibitory and bactericidal concentrations (MIC and MBC) and detected its bioconstituents using gas chromatography-mass spectrometry (GC-MS) analysis besides evaluated its effect in vivo in carp either alone or combined with antibiotic to prevent or treat V. anguillarum infection. A total of 180 fish were divided into 6 groups; G1: negative-control, G2: V. anguillarum infected-control, G3: infected-(marbofloxacin (MAR) 10 mg/kg body weight), G4: infected-(VAC 1gm/kg ration), G5: infected-(VAC 1 gm/kg + MAR 10 mg/kg) all treatments lasted 7 days and G6: prophylactic treated-(VAC 1 gm/kg/30 day) then challenged. Results of scanning electron microscope revealed changes in bacterial morphology and loss of flagella by VAC where its MIC and MBC were 1.95 and 15.63 mg/ml respectively. Growth performance and survival rate improved in all treated groups in this descending order (G6, G4 then G5). All treatments significantly increased total protein, albumin, globulin, superoxide dismutase and decreased aspartate and alanine aminotransferases activities, malondialdehyde, urea and creatinine than G2 and mostly near to G1 in this ascending order (G3, G4 then G5). In G6, VAC protected carp from the infection and improved growth, survivability and most of blood parameters. MAR residue in fish musculature needed 4 days as a withdrawal period to be less than the maximum residue limits (MRL), while combination of VAC with MAR decreased it less than the MRL from the 1st day post treatment. Finally, VAC had a considerable antibacterial activity against V. anguillarum in both prevention and treatment assays. It can be used either alone or adding with MAR.

Two hundred and fifty samples (Marketable milk, Ras cheese, Domiati cheese and ice cream), were randomly obtained from various dairy shops, supermarkets and ice cream shops in Assiut City, Egypt, during the period of November 2022 to March 2023. These samples were examined for the detection and counting of Bacillus cereus. The positive B. cereus isolates were analyzed by PCR to detect 16s rRNA gene for B. cereus, cytotoxin K (cyt K) and emetic gene (ces). Out of the 250 examined samples, 14 (5.6%) were contaminated by B. cereus. The analyzed ice cream had the highest prevalence (11.53%), followed by Ras cheese samples. The prevalence of ces gene recorded in the examined isolates was 57.14%, while cyt K gene was found in all isolates. Moreover, proteolytic and lipolytic activity investigations revealed that nearly all strains released protease enzyme (92.85%), most of which (64.28%) could produce lipase enzyme.

A total of 180 samples were taken from diseased and freshly dead broiler chickens of various ages from various farms in El-Minya and Beni-Suef governorates and transferred to the lab for bacterial isolation and further molecular examination targeting E. coli. The results showed that 91 of 180 samples (50.6%) tested positive for E. coli. The   prevalence of some in vitro virulence markers of avian pathogenic E. coli was Congo red binding (CRB) (95.6% positivity) and moderate to strong biofilm production (92%). On 5% sheep blood agar, (67%) of examined isolates showed alpha hemolysis, while (27%) showed gamma hemolysis  and (5.5%) showed beta hemolysis. All the tested isolates exhibited a multidrug resistance (MDR) pattern. E. coli isolates demonstrated various degrees of resistance against, amoxicillin–sulbactam (82%) followed by streptomycin (76%), cefotaxime and trimethoprim/sulphamethoxazole (73%), tetracycline and ciprofloxacin (68%), chloramphenicol (66%), cefaclor (65%), cefixime (62%) respectively. Five MDR selected isolates were examined using PCR. The intended virulence genes were iss, tsh, fimH, and iroN genes. The genes iss and fimH were detected in all of the isolates investigated, whereas iroN was present in four isolates but tsh was found in only one isolate.

Environmental pollution remains a major global health concern, particularly when it comes to heavy metals, which are associated with various health hazards. Among the prevalent heavy metals in the environment is cadmium (Cd). As a result, the current study aimed to investigate the nephroprotective potential of olive leaves extract (OLE) against Cd-induced chronic renal injury. Forty-eight albino rats were divided into four equal groups. Rats in the control group were received distilled water orally, while those in the OLE group were orally administered OLE 200 (mg/kg b.wt.) daily. The cadmium-intoxicated group rats were orally gavage 5 mg Cd/kg b.wt. twice a week and the OLE+Cd group received the same doses of both OLE and CdCl2. After 4 and 8 weeks of the experiment, blood and kidney samples were collected for analysis of kidney function test and histopathological examination. Oral administration of cadmium chloride (CdCl2) for 4 and 8 weeks resulted in nephrotoxicity, evidenced by a significant increase (P<0.05) in urea, uric acid, and creatinine levels. These biochemical changes were accompanied by distinct histopathological alterations, including renal hemorrhage, edema and vasculitis with severe glomerular and tubular necrosis as well as periglomerular fibrosis and marked interstitial fibrosis. Treatment with OLE exhibited a remarkable reduction in these histopathological changes and restored the serum parameters toward normal levels. In conclusion, OLE has a time-dependent mitigating effect against Cd-induced nephrotoxicity by reducing inflammation, glomerulotubular injury, and renal fibrosis, indicating that it is a potential natural product in counteracting chronic nephrotoxicity.

In this study, an E. coli phage JH2 was isolated from swine feces on an industrial farm. Bacteriophage JH2 could carry 85% (n = 32) O8 ETEC (Enterotoxigenic Escherichia coli) strains when 81 alike-strains from Vietnam and China were tested. The genome size could be as large as JH2 had 77187 bps, a linear, double-stranded and CG = 38.89%. It shared a height similarity of 94.9% to Staphylococcus phage SA1 of GU169904 with 147303 bps, which is about double the size. JH2 carried 22 tRNA and no gene for known toxins. Under the electronic microscope the phage presented icosahedral heads, necks, contractile and long tails, and it belonged to the Myoviridae family. The phage demonstrated high stability to the physical and chemical factors, thermal sensitivity at 60 °C and acid and alkaline resistance (pH = 5-9). The genome of JH2 contained 131 putative open reading frames (ORFs). One hundred and twenty-six ORFs (out of 131) were predicted and 121 ORFs had putative functions. From database, 22 tRNAs were predicted in the JH2 genome. Staphylococcus phage SA1 contains an almost complete phage genome of JH2 phage. The complete genome sequence of JH2 was analyzed. Comparing the complete genome sequences of JH2 and Staphylococcus phage SA1 showed 94.9% similarity.