Postbiotic, anti-inflammatory, and immunomodulatory effects of aqueous microbial lysozyme in broiler chickens.

Lysozymes, efficient alternative supplements to antibiotics, have several benefits in poultry production. In the present study, 120, one-day-old, Ross 308 broiler chickens of mixed sex, were allocated into 2 equal groups, lysozyme treated group (LTG) and lysozyme free group (LFG), to evaluate the efficacy of lysozyme (Lysonir®) usage via both drinking water (thrice) and spray (once). LTG had better (p = 0.042) FCR, and higher European production efficiency factor compared to LFG (p = 0.042). The intestinal integrity score of LTG was decreased (p = 0.242) compared to that of LFG; 0.2 vs. 0.7. Higher (p ≤ 0.001) intestinal Lactobacillus counts were detected in chickens of LTG. Decreased (p ≤ 0.001) IL-1ß and CXCL8 values were reported in LTG. The cellular immune modulation showed higher (p ≤ 0.001) opsonic activity (MΦ and phagocytic index) in LTG vs. LFG at 25 and 35 days. Also, higher (p ≤ 0.001) local, IgA, and humoral, HI titers, for both Newcastle, and avian influenza H5 viruses were found in LTG compared to LFG. In conclusion, microbial lysozyme could improve feed efficiency, intestinal integrity, Lactobacillus counts, anti-inflammatory, and immune responses in broiler chickens.

Exogenous aqueous and spray microbial lysozyme enhanced growth in commercial broiler chickensThe postbiotic effects of microbial lysozyme modulated intestinal integrity.Anti-inflammatory, as well as local, cellular, and humoral immune response were stimulated by lysozyme supplementation.

The Efficacy of Bacteriocins Against Biofilm-Producing Bacteria Causing Bovine Clinical Mastitis in Dairy Farms: A New Strategy.

Using an alternative bio-product is one of the most promising ways to control bovine mastitis and avoid new intra-mammary infections. The aims of this study were to ascertain the prevalence of biofilm-forming bacteria responsible for causing clinical mastitis in dairy herds and to assess the effectiveness of bacteriocins, produced by Bacillus subtilis, in controlling the growth of these bacteria in the milk of animals. A total of 150 milk samples were collected from cows and buffalos suffering from mastitis and the etiological agents were isolated and identified by the VITEK-2-COMPACT-SYSTEM®. Additionally, the capability of the bacterial isolates to produce biofilms was determined. RT-PCR was used to detect enterotoxin-producing genes (sed and seb), resistance genes (mecA and blaZ), and biofilm-associated genes (icaA and fnbA) in the isolated bacteria. The susceptibility patterns of the bacterial isolates to bacteriocins were assessed using an agar well-diffusion assay. S. aureus was significantly more capable of producing biofilms than coagulase-negative Staphylococcus isolates. S. ubris was the strongest biofilm producer among the Streptococcus species. The sensitivity profiles of the Staphylococcus spp. (S. aureus and coagulase-negative Staphylococcus) and their biofilm producers to bacteriocins were significantly higher (100% and 90%, respectively) at the same concentration. Bacteriocins had a lethal effect on Staphylococci, Streptococci, and biofilm development at a dose of 250 µg/mL. In dairy farms, bacteriocins are a viable alternative treatment for the prevention and control of bovine clinical mastitis.

Biofilm forming potentiality of Escherichia coli isolated from bovine endometritis and their antibiotic resistance profiles.

OBJECTIVE: The objectives of this study were to determine the biofilm-forming capability and antimicrobial susceptibility of Escherichia coli recovered from bovine endometritis samples. MATERIALS AND METHODS: A total of 120 uterine specimens were collected from cows suffering from endometritis for bacteriological examination. Antimicrobial susceptibility testing was carried out for all isolated E. coli by using the disc diffusion method. The isolates were phenotypically studied for biofilm-forming ability by cultivation on yeast extract -casamino acids Congo red agar (CRA). Some randomly selected isolates were chosen for the molecular identification of some virulence and resistance genes. RESULTS: A total of 58(48.3%) E. coli isolates could be isolated from the 120 samples. Antimicrobial susceptibility testing exhibited that 91.4%, 79.3%, 79.3%, 74.1%, and 58.6% of the isolates were sensitive to gentamicin, amoxicillin-clavulanic acid, ciprofloxacin, cephalexin, and sulfamethoxazole- trimethoprim, respectively. On the other hand, 91.4% and 70.7% isolates were resistant to cefotaxime and doxycycline, respectively. Cultivation on CRA revealed that 46.6% of isolates were biofilm producers. The molecular detection of resistance and virulence genes declared that all isolates harbored bla TEM, sul1, tetA, qnrS, bla CTX-M , and fimH with a percentage of 100%, papC (40%), and hlyA (10%). FimH was the most prevalent biofilm-associated gene. CONCLUSION: The present study highlights the high prevalence of multi-drug- resistant E. coli associated with bovine endometritis. The detection of the fimH gene is circumstantial evidenced that this gene has a crucial role in biofilm formation in intrauterine pathogenic E. coli.