This experiment was conducted to evaluate the effect of some feed restriction regimes on the performance, carcass characteristics and hematological values of broiler chickens. A number of 480 one-day-old Cobb broilers were distributed into 24 floor pens and reared for 42 days. A basal diet was formulated according to the NRC (1994) recommendations for starter (1-11 d), grower (12-28 d) and finisher (29-42 d) periods. The restricted birds were fed 8 h per day from 7 to 21 (R7-21d), 14 to 28 d (R14-28d) or from 21 to 35d (R21-35d), while the control birds were fed ad libitum. Birds and feed were weekly weighed, and dead birds were submitted to necropsy to determine the cause of death. At the end of experiment, blood samples were taken from 3 birds per pen, birds were weighed, and organ weights were recorded. All birds in the feed restriction treatments had lower body weight gain and feed intake than those fed ad libitum. Feed conversion ratio (FCR) was better in birds under R7-21d as compared to the control group (p<0.05). R7-21d and R14-28d birds presented lower general mortality and death due to ascites as compared to ad libitum-fed broilers. The birds under R21-35d and R14-28d treatments had lower breast weight and abdominal fat weight as compared to control birds, respectively (p<0.05). A similar trend was observed for the percentage of the mentioned cuts. The right/total ventricular weight ratio (RV/TV) was significantly lower both in R7-21d and R14-28d treatments as compared to the control group. Blood constituents, such as glucose, cholesterol, and lactate dehydrogenase were also significantly altered by feeding regimes (p<0.05). The results of present study showed that R7-21d reduced ascites incidence, but had no significant effect on growth performance

The aim of this study was to evaluate the effects of different levels of silver nanoparticles (Ag-NPs) coated on zeolite on performance, gastrointestinal microflora, heterophile to lymphocyte ratio and humoral immune system responses of broiler chickens. Three hundred seventy-five chicks (Cobb 500) in a completely randomised design were distributed to five diets: 1) basal diet, 2) basal diet containing 1% zeolite and 3, 4 and 5) basal diet containing 1% zeolite coated with 25, 50 and 75 ppm Ag-NPs. Performance traits were recorded and blood samples were taken to determine antibody response against Newcastle on day 14, infectious bursal disease on day 21 and serum immunoglobulins (Igs) were determined on day 42. Heterophile to lymphocyte ratio was evaluated on days 28, 35 and 42. The result showed that feed conversion ratio (FCR) was significantly decreased in Ag-NP treatments compared with control group (p < .05). Total anaerobic bacteria and the population of Escherichia coli in ileum and caecum were decreased (p < .05). The highest number of lactobacillus was observed in NS50 (p < .05). Antibody response against Gumboro was decreased as well as the amount of IgY antibody in Ag-NPs treatments. Significant differences were observed in heterophile to lymphocyte ratio on day 28 and 35 and the highest amount was observed in NS50 group (p < .05). In conclusion, although this study showed that using Ag-NP dietary coated on zeolite could improve gut microflora, but Ag-NPs could also have side effects on the immune mechanism of broiler chickens.

With rising concerns about antibiotic resistance and its consequences on public health, the identification of safe and effective alternatives to antibiotics in the poultry industry has become increasingly critical. This study aimed to evaluate the effects of supplementing drinking water with apple vinegar and essential oils, compared to an antibiotic growth promoter, on the growth performance, serum lipid profile, antioxidant status, intestinal morphology, and gastrointestinal microflora population of broiler chickens. A total of 240 one-day-old male broiler chickens were randomly assigned to four treatments, each consisting of six replicate pens with ten birds per pen. The broiler chickens received the following experimental treatments: normal drinking water without additives (control) and drinking water supplemented with antibiotic (0.25 ml/L), apple vinegar (1 ml/L), and essential oils blend (0.5 ml/L). The results showed that adding antibiotic or essential oils blend to drinking water improved body weight gain and feed conversion ratio throughout the entire rearing period (P < 0.05). The serum levels of cholesterol and low-density lipoprotein in broilers that received apple vinegar or essential oils blend were lower than those in the control and antibiotic groups (P < 0.05). The essential oils blend treatment significantly increased the activity of glutathione peroxidase and superoxide dismutase in the serum of broiler chickens compared to the other treatments (P < 0.05). Furthermore, adding essential oils blend to the drinking water increased villus height and villus height to crypt depth ratio in the jejunum of broilers (P < 0.05). The broiler chickens in the apple vinegar and essential oil blend groups also exhibited a lower population of Enterobacteriaceae and a higher count of lactic acid bacteria in the ceca (P < 0.05). In summary, the addition of essential oils blend to the drinking water of broiler chickens has beneficial effects on production performance and can serve as an effective alternative to antibiotic growth promoters.

The inclusion of raw rapeseed meal (RSM) in broiler diets is often limited due to the presence of anti-nutritional factors. Microbial fermentation has been proposed as an effective strategy to improve the nutritional value of plant-based protein sources. This study aimed to evaluate the effects of replacing soybean meal (SBM) with either RSM or fermented RSM (FRSM) on growth performance, gut microbiota, biochemical indices, intestinal morphology, nutrient digestibility, and cecal short-chain fatty acid concentrations in broiler chickens. A total of 300 one-day-old male Cobb 500 broiler chicks were randomly assigned to five dietary treatments and reared for 42 days. The experimental diets included a corn-SBM-based control diet; a diet in which SBM was entirely replaced with RSM; and three diets in which FRSM replaced RSM at 33.3 % (FRSM₃₃), 66.6 % (FRSM₆₆), and 100 % (FRSM₁₀₀), respectively. Replacing SBM with RSM significantly reduced body weight gain and increased feed conversion ratio (P < 0.05). In contrast, complete substitution of SBM with FRSM mitigated these adverse effects, significantly improving growth performance compared with diets containing high levels of RSM (P < 0.05). The inclusion of FRSM in place of SBM significantly increased lactic acid bacteria counts in the crop and reduced coliform counts in the ileum (P < 0.05). Furthermore, birds receiving FRSM diets exhibited significantly lower serum concentrations of total cholesterol, triglycerides, very low-density lipoprotein cholesterol, and low-density lipoprotein cholesterol (P < 0.05). The jejunal villus height to crypt depth ratio and cecal concentrations of butyric and lactic acids were significantly higher in birds fed diets containing FRSM compared with those fed RSM or the SBM diet (P < 0.05). The apparent ileal digestibility of crude protein and ether extract was also significantly improved in FRSM diets relative to the RSM diet (P < 0.05). Under the conditions of this study, replacing SBM with FRSM improved growth performance, nutrient digestibility, gut microbiota composition, short-chain fatty acid concentrations, and intestinal morphology relative to RSM diets. Although FRSM did not fully match the growth performance achieved with SBM, it improved nutrient utilization and gastrointestinal health. These findings suggest that FRSM may serve as a functional alternative protein source to SBM by promoting gut integrity and supporting physiological health in broiler chickens.