As the use of antibiotics has been banned or reduced in certain countries in animal industries, the search for new alternatives to antibiotics has been and will continue to be a research subject in poultry for several years. This study aimed to evaluate the effect of basil, thyme and sage essential oils (EO) in broiler chickens’ diets. A total of 120 Cobb 500 broiler chickens aged 12 days were distributed into four homogeneous groups of thirty chickens with six replicates of five broilers each, raised until 42 days of age. For the diets, corn, soybean meal, corn gluten and wheat were used as the main ingredients for the control diet (CON), and three experimental diets were formulated as follows: a diet containing 0.05% essential oil from basil (EOB), a diet containing 0.05% essential oil from thyme (EOT), and a diet containing 0.05% essential oil from sage (EOS). The results showed that production performances, European Production Efficiency Factor (EPEF), European Broiler Index (EBI) and carcass weight were improved (p < 0.05) in the experimental groups compared with the control; however, no significant effect in anatomical parts development was observed. Lightness (L *) and hue angle (H *) colorimetric meat parameters were (p < 0.05) altered but without an effect on meat texture. The antioxidant capacity and total polyphenols content in the thigh meat and total n-3 and n-6 polyunsaturated fatty acids were higher in the experimental samples compared with the control. The intestinal microbiota was also significantly altered with a lowering of Escherichia coli, Coliforms and staphylococci in the small intestine and caecum and an increased lactobacilli count in the experimental groups compared with the control. Overall, all EO-supplemented diets showed the potential to improve meat quality; however, EOS was more effective in altering the chicken microbiota in the small intestine and caecum.

The aim of the study was to characterize the Bacillus subtilis ATCC 6051a strain, in order to establish its probiotic utility in piglet nutrition. The strain was assayed morphologically, culturally, biochemically, for hemolytic activity and enzymatically (amylase and protease). The identification and analysis of the biochemical characteristics was performed by catalase assay, API 50 CHB Biomerieux strips, apiweb API 50 CHB V 4.0 soft (B. subtilis very good identification, 99.4% ID) and ABIS online. The hemolytic activity was assayed on blood agar medium. The growth activity of strain was evaluated in two ways: static incubation (30 °C, 24 h, 1.36 x 108 CFU/ml) and under constant agitation (30 C, 24 h, 150 rpm, (1.6 x 109 CFU/ml). The strain is a Gram - positive and rodshaped bacteria, arranged in short chains or in small irregular pairs with ability to produce spores on nutrient medium. The endospores were central, paracentral and subterminal, which did not deform the vegetative cell. The strain growth was aerobic and was non - hemolytic. The enzymatic process was observed by appearance of distinct zones around strain colonies. In conclusion, the results suggested that the strain present probiotic traits and can be further assessed for other probiotic characters (resistance to pH 2.0, resistance to bile acids and salts, antibacterial activity, induction of local immune response etc.).

The solid-state fermentation (SSF) efficiency of Bacillus licheniformis ATCC 21424 (BL) on various agro-industrial by-products such as oilseed cakes [hemp (HSC), pumpkin (PSC), and flaxseed (FSC)] was evaluated by examining the nutritional composition, reducing sugars, and in vitro protein digestibility (IVPD) for use in animal nutrition. SSF significantly decreased crude protein, along with changes in the total carbohydrates (p < 0.05) for all substrates fermented. An increase in crude fat for HSC (1.04%) and FSC (1.73%) was noted, vs. PSC, where the crude fat level was reduced (−3.53%). Crude fiber does not differ significantly between fermented and nonfermented oilseed cakes (p > 0.05). After fermentation, neutral detergent fiber (NDF) and acid detergent fiber (ADF) significantly increased for HSC and FSC (p < 0.05), as well as for PSC despite the small increase in ADF (4.46%), with a notable decrease in NDF (−10.25%). During fermentation, pH shifted toward alkalinity, and after drying, returned to its initial levels for all oilseed cakes with the exception of PSC, which maintained a slight elevation. Further, SSF with BL under optimized conditions (72 h) increases the reducing sugar content for FSC (to 1.46%) and PSC (to 0.89%), compared with HSC, where a reduction in sugar consumption was noted (from 1.09% to 0.55%). The viable cell number reached maximum in the first 24 h, followed by a slowly declining phase until the end of fermentation (72 h), accompanied by an increase in sporulation and spore production. After 72 h, a significant improvement in water protein solubility for HSC and FSC was observed (p < 0.05). The peptide content (mg/g) for oilseed cakes fermented was improved (p < 0.05). Through gastro-intestinal simulation, the bacterial survivability rate accounted for 90.2%, 101.5%, and 85.72% for HSC, PSC, and FSC. Additionally, IVPD showed significant improvements compared to untreated samples, reaching levels of up to 65.67%, 58.94%, and 80.16% for HSC, PSC, and FSC, respectively. This research demonstrates the advantages of oilseed cake bioprocessing by SSF as an effective approach in yielding valuable products with probiotic and nutritional properties suitable for incorporation into animal feed.

A total of 15 strains of lactic acid bacteria (LAB) were isolated from the broiler chicken’s gastrointestinal tract. All isolates were phenotypical and genetically identified. Among these isolates, only six were biochemical (API 50 CHL and ABIS soft) and genetically (16S rRNA sequencing) confirmed as Lactobacillus acidophilus, Limosilactobacillus fermentum, Levilactobacillus brevis, and Ligilactobacillus salivarius. Probiotic properties, including tolerance to pH (pH 2.0 and 3.0), bile salts (0.3% oxgall), hemolysis activity, and antibiotic susceptibility, were evaluated. Three isolates of the latter isolates showed high resistance at low pH values (73.74% to 98.20%) and bile salt concentrations (77.89% to 99.49%). The antibiotic test presented 100% resistance of LAB to gentamicin, lincomycin, enrofloxacin, and streptomycin lower than the 0.5 mm inhibition zone diameter. Selected strains (L. acidophilus IBNA 64, L. salivarius IBNA 33, and L. salivarius IBNA 41) were exposed to the spray-drying process based on observable probiotic potential. A maltodextrin-glucose solution was used as a thermoprotectant. After spray drying, a reduction in strain viability was noted (10⁸ to 10⁴ CFU/g). In conclusion, only L. salivarius (IBNA 33 and IBNA 41) could be used as a possible probiotic, and further studies are needed to ensure their safe application in the animal nutrition field with beneficial effects for improving performance and pathogen microorganism control from intestines equilibrating the microbiota composition.

The study aimed to assess the effects of the dietary supplementation of microencapsulated L. acidophilus and L. plantarum and their combination on the growth performance, organ development, diarrhoea incidences, blood profiles, intestinal histomorphology and microflora in weaned piglets. For that, 160 piglets with an average body weight (BW) of 8.52 ± 0.15 kg were divided into four groups (40 piglets/group) and allotted to one of the four dietary treatments as follows: a basal diet (C diet) or a basal diet containing 1 × 10⁸ CFU/g of L. acidophilus (LA diet), or a diet containing 3 × 10⁸ CFU/g of L. plantarum (LP diet) and a diet with the combination of both bacterial strains (LA + LP diet) for 21 days. On day 14, probiotics significantly increased ADFI, while FCR was higher in the LA and LP groups than the C and LA + LP groups. No effects (p > 0.05) on visceral organs weight, intestinal pH and biochemical parameters among treatments were noticed. Treatments significantly lowered diarrhoea incidence compared to control. Villus width was greater (p < 0.05) in all small intestinal segments in piglets fed probiotics. In the jejunum and ileum villus length, crypt length, and total villi length were higher (p < 0.05), particularly in the LA + LP group. The probiotics, particularly the LA + LP group, modulated the cecal, jejunum and ileum microbial community structure and increased (p < 0.05) the amount of Lactobacillus spp. while decreasing the populations of Escherichia coli and Staphylococcus. Our results indicated that dietary supplementation of microencapsulated probiotics, particularly the combination of L. plantarum and L acidophilus strains, maintained growth performance, lowered diarrhoea incidence and beneficially altered the intestinal architecture and microbial populations of weaned piglets.