The objective of this study was to investigate the effects of thyme and oregano essential oils (as growth promotors), individually and in combination, on the health, growth performance, and prevalence of muscle abnormalities in broiler chickens. Six hundred day-old Cobb 500 hybrid chickens were randomized into four dietary treatment groups with three replicates each. Chicks in the control group (C) received a basal diet, while the experimental treatment groups received basal diets containing 350 mg/kg of thyme oil (T1), 350 mg/kg of oregano oil (T2), and 350 mg/kg of thyme and oregano oil (T3). Growth performance parameters were evaluated at 14, 28, and 42 days. The broilers in treatments T1 and T2 had significantly higher body weights than the control group. The feed conversion ratio was the lowest in chicks who received oregano oil, followed by those fed thyme oil. The overall prevalence of growth-related breast muscle abnormalities (including white striping and white striping combined with wooden breast) in groups receiving essential oils (T1, T2, and T3) was significantly higher than in the control group (C). The thyme and oregano oil diets showed no significant differences in antibody titers against Newcastle disease or interferon-γ (INF-γ) serum levels. In conclusion, thyme and oregano oils had a positive impact on the growth performance of broiler chickens but increased the incidence of growth-related breast muscle abnormalities.

The objective of this research was to investigate the effects of a natural herb extract1 (HE) on the general growth performance and the incidence of muscle abnormalities (white striping and wooden) of broiler chicks. A total of 504 one-day old chicks (Ross 500) were used in the experiment and randomly partitioned into 3 treatments with 7 replicates in each (24 chicks per replicate). Three experimental diets (C: regular feed; T1 and T2 (supplemented with HE at levels of 0.20 and 0.30 ml/L, respectively). The herbal extract was supplemented in drinking water. Feed intake, body weight and feed conversion ratio were monitored at days 14, 28 and 42 of the feeding trial. Moreover, the yield of visceral organs, carcass cuts, and the incidence of muscle abnormalities were evaluated at different ages of slaughter (34, 41and 48 days). Results showed that weights, feed conversion ratios (FCR) and dressing percentages (DP) increased (p<0.05) in birds supplemented with herb extract compared to control birds. However, HE supplementation had no significant effects on carcass cuts and some visceral organs. Meat quality was improved by HE supplementation as the incidence of white stripping (WS) and WS plus wooden meat cases dramatically reduced, in particular at 34 days of age, day of slaughter. It can be concluded that feeding the herbal extract has significant positive effects on broilers general performance, feed efficiency and meat quality.

The objective of this study was to investigate the effect of dietary supplementation with black cumin seed meal (BCSM) and coconut meal (CM) on the performance and cecal microbiota of Cobb 500 hybrid broilers. The study was conducted on 600 chicks on the first day of hatching; the chicks were randomly distributed equally into 12 equal-sized floor pens. Four dietary treatments (C, T1, T2 and T3) were replicated three times (50 chicks/replicate): C was the control group; T1 was supplemented with 10% BCSM; T2 was supplemented with 10% CM; T3 was supplemented with 5% BCSM and 5% CM. At slaughter age on day 35, our findings showed that treatment T2 increased significantly body weight and feed conversion ratio (FCR) compared to C, T1 and T3. In addition, the hot carcass dressing percentages in treatments T1, T2, and T3 were significantly higher than that of the C group. The results of relative normalized comparative gene expression of Clostridioides difficile, Roseburia and Streptococcus were not significantly changed in all treatments (p > 0.05). Treatment T1 resulted in a significant decrease in gene expression of the entire microbiota, while treatment T2 resulted in a significant increase in gene expression of all microbes, leading to an enriched and diverse microbial community. It can be concluded that supplementation with 10% BCSM is beneficial in inhibiting pathogenic microbes during early post-hatch days. In contrast, CM may promote and enhance the diversity of microbial communities during broiler growth. The inclusion of non-conventional feed ingredients in poultry diets may improve growth performance and may reduce the cost of broiler feed.

Food Science of Animal Resources (Food Sci. Anim. Resour.) is an international, peer-reviewed bimonthly journal publishing original research and reviews on basic and applied aspects of the use of animal resources including the meat, egg, dairy, and edible insect/worm products. Food Sci. Anim. Resour. is published and distributed by the Korean Society for Food Science of Animal Resources.

The objective of this study was to evaluate the effects of soybean lecithin in broiler diets formulated with either fried or non-fried soybean oils (as an energy source), on growth performance, digestibility, and some serum parameters. A total of 600 broilers (50% male) were assigned to 4 experimental groups (with 10 replicates of 15 birds each): (i) group (S) fed with soybean oil only, (ii) group (SL) fed with soybean oil + lecithin (0.035% in feed), (iii) group (F) fed with fried soybean oil only, and iv) group (FL) fed with fried soybean oil + lecithin (0.035% in feed). Broilers that received lecithin with fried soybean oil (group FL) exhibited significantly higher body weights (1.228 vs. 1.210 kg, p < 0.05 and 1.935 vs. 1.917 kg, p < 0.05) than group F in the last two experimental periods (22–28 and 29–35 days), respectively. On the contrary, the addition of soybean lecithin to diets formulated with either fried or non-fried soybean oil resulted in a significant increase in weight of some carcase cuts (thigh, breast) and a significant decrease in some visceral organs (intestine, liver, viscera), without affecting the digestibility parameters here assessed. Our findings revealed that the addition of soybean lecithin to standard soybean oil (group SL) significantly decreased serum triglycerides (77.16 vs. 83.46 mg/dL, p < 0.05) compared to group S. In conclusion, it was possible to use recovered frying soybean oil in broiler diets without a negative impact on growth performance and serum triglyceride level, while these parameters were improved by the addition of soybean lecithin.