Objective: The objective of this study was to evaluate the effects of supplementing quercetin extracted from Sophora japonica flower (QS) to the diet of broiler chicks on their growth performance, apparent nutrient digestibility, cecal microbiota, serum lipid profiles, relative organ weight, and breast muscle quality.Methods: A total of 1,088 1-day-old broiler chicks (mixed sex) were randomly assigned to four groups based on the initial body weight (43.00±0.29 g). The experimental period was 35 days (starter, days 0 to 7; grower, days 7 to 21; finisher, days 21 to 35). There were 17 replicate cages per treatment and 16 birds per cage. Dietary treatments consisted of birds receiving basal diet without quercetin as the control group and treatment groups consisted of birds fed basal diet supplemented with 0.2, 0.4, or 0.6 g/kg QS.Results: With the increase of the QS dosage, body weight gain during days 0 to 7 (p = 0.021), 7 to 21 (p = 0.010), and 1 to 35 (p = 0.045), feed intake during days 0 to 7 (p = 0.037) and 1 to 35 (p = 0.025), apparent dry matter digestibility (p = 0.008), apparent energy retention (p = 0.004), cecal lactic acid bacteria counts (p = 0.023), the relative weight of breast muscle (p = 0.014), pH value from breast muscle (p<0.001), and the water holding capacity of breast muscle (p = 0.012) increased linearly, whereas the drip loss from breast muscle (p = 0.001) decreased linearly.Conclusion: The addition of QS in the diet of broiler chicks had positive effects on the breast muscle yield and breast muscle quality, and improved the dry matter digestibility and energy retention by increasing cecal beneficial bacteria counts, thus improving growth performance.

Objective: The purpose of this study was to evaluate the effects of supplementing herbal active ingredients (YGF251) which can promote the secretion of insulin-like growth factor-1 (IGF-1) in the diet on production performance, egg quality, blood hematology, and excreta gas emission in laying hens.Methods: A total of 288 ISA Brown (41-week-old) laying hens with an initial body weight of 1.83±0.68 kg were randomly assigned to 1 of 4 dietary treatments in a randomized block design based on body weight. Each treatment had 12 replicate cages having 6 adjacent cages per replicate (hens are kept in cages alone). The experimental period was 35 days. Dietary treatments were based on the corn-soybean meal-wheat-based basal diet and supplemented with 0.00%, 0.05%, 0.10%, or 0.15% YGF251.Results: There was a linear increased egg weight in weeks 1 to 5 (p<0.05), egg mass in week 1 (p<0.05) and weeks 1 to 5 (p<0.05), egg strength on day 7 (p<0.05), 21 (p<0.01), and 35 (p<0.01), eggshell thickness on day 21 (p<0.05) and 35 (p<0.01), haugh unit on day 21 (p< 0.01) and 35 (p<0.05), serum IGF-1 concentration on day 21 (p<0.05) and 35 (p<0.01), and serum total protein concentration on day 35 (p<0.05) were observed with the supplementing YGF251 increased in the diet, while feed conversion ratio in weeks 1 to 5 (p<0.05) and excreta ammonia emission (p<0.01) decreased linearly with the dose of YGF251 increased.Conclusion: Dietary supplementation of YGF251 positively affected the production performance and egg quality of laying hens through increasing serum IGF-1 concentration in a dose-dependent manner. Moreover, YGF251 supplementation improved barn environment by reducing excreta noxious gas emission.

Journal of Animal Science and Technology (JAST) is a peer-reviewed, open access journal publishing original research, review articles and notes in all fields of animal science. Topics covered by the journal include: genetics and breeding, physiology, nutrition of monogastric animals, nutrition of ruminants, animal products (milk, meat, eggs and their by-products) and their processing, grasslands and roughages, livestock environment, animal biotechnology, animal behavior and welfare.