ABSTRACT Two experiments were conducted to evaluate the effects of β-mannanase on egg production performance, egg quality, intestinal microbiota, viscosity, and ammonia concentration in laying hens. In Exp. 1, two hundred and seventy 30-wk-old Hy-Line Brown laying hens were assigned to 6 diets arranged in a 3 × 2 factorial of three levels of MEn and CP [(a corn-soybean meal based diet (HEHP), a diet containing 50 kcal of MEn/kg and 1.0% less energy and CP than the HEHP (MEMP), and a diet containing 80 kcal of MEn/kg and 1.5% less energy and CP than HEHP (LELP)], and β-mannanase supplementation (0 or 0.04%). In Exp. 2, A total of two hundred and sixteen62-wk-old Hy-Line Brown laying hens were assigned to 6 dietary treatments in a 3 × 2 factorial arrangement. In Exp. 1, β-mannanase supplementation increased egg production rate in hens fed LELP diet, but not in those fed HEHP or MEMP diet (interaction, p<0.01), and the interaction was significant (p<0.01) for egg mass. β-mannanase supplementation decreased (p<0.05) ammonia concentration. In Exp. 2, the supplementation of β-mannanase increased egg production rate and egg mass in hens fed LELP diet, whereas no differences were found in those fed HEHP or MELP diet (interaction, p<0.01). The supplementation of β-mannanase in a lower energy and protein diet resulted in similar production performance when compared to high-energy and high-protein diet during early and late stages of egg production.

ABSTRACT This study was conducted to investigate the effects of dietary oxidized oil and natural polyphenol antioxidants on laying performances and egg quality of laying hens. A total of two hundred, 61-week-old Lohmann Brown laying hens were divided into five groups, consisting in four replicates of 10 birds each. They were fed one of the five experimental diets (fresh oil only, oxidized oil without antioxidants, oxidized oil with vitamin E 200 ppm, oxidized oil with vitamin E 100 ppm + Cabanin CSDⓇ 100 ppm, oxidized oil with Cabanin CSDⓇ 500 ppm)respectively, for 6 weeks. There were no significant differences in laying performances and egg weight among the treatments. However, egg mass in group fed oxidized oil with vitamin E 100 ppm + Cabanin CSDⓇ 100 ppmwas significantly higher than group fed oxidized oil only (p<0.05). Eggshell thickness and eggshell strength was not affected by feeding of oxidized oil and antioxidants. Haugh unit checked after storage of 14 d from the end date of the trial showed significant difference (p<0.05). Serum superoxide dismutase (SOD) like activity was significantly higher in antioxidant treated groups. The level of serum glutamic oxaloacetic transaminase (GOT) was significantly lower in groups fed vitamin E 100 ppm + Cabanin CSDⓇ 100 ppm or Cabanin CSDⓇ 500 ppm compared to groups fed oxidized oil without antioxidant. The number of total microbes, lactobacilli, and Enterocossus faecium showed significant difference favored to antioxidants groups. This study indicates that addition of oxidized oil to layer diet may have harmful effect on oxidative status and egg quality, but concurrent addition of vitamin E and natural polyphenol can alleviate the toxic effect of oxidized oil.

ABSTRACT The present study was conducted to evaluate the effects of feeding broilers with garlic fermented by Leuconostoc citreum SK2556. A total of 250 male broiler chicks was randomly housed into 25 floor pens. Five dietary treatments with five replicates of 10 chicks each (n=50 chicks/treatment). A corn and soybean meal based diet was used as the control diet (NC). The experimental diets were formulated by mixing the basal diet either with antibiotics (10 ppm; PC) or fermented garlic (FG) at the concentrations of 0.1% (FG1), 0.3% (FG3) or 0.5% (FG5) in diets. Daily weight gain, feed intake, and feed:gain ratio were not affected by any of the dietary treatments. Average daily gain on day 21 linearly increased (p= 0.024) with increasing FG levels. The relative weight of the bursa of Fabricius showed a progressive decline with increasing the FG levels. Jejunal villus height was not influenced by dietary treatments. Villus width linearly decreased as FG levels increased (p= 0.17). Jejunal crypt depth was significantly lower (p< 0.05) in the FG1 and FG3 groups compared with the NC group. Villus height:crypt depth ratio linearly increased (p= 0.018) with increasing FG levels. The population of cecal microflora was not altered by dietary treatments. Broiler chickens fed the FG5 diet exhibited (p< 0.05) higher blood levels of total protein and cholesterol compared with those fed the NC diet. Collectively, the results show that dietary FG marginally affected growth performance, especially during the first days rearing, improved intestinal morphology, and altered blood characteristics of broiler chickens.

ABSTRACT This experiment was conducted to evaluate the dietary supplementation of canola meal (CM) on the growth performance, carcass characteristics, antibody titers against Newcastle disease virus and Infectious bronchitis virus, and blood profiles of broiler chickens. In total 600 day-old feather-sexed Ross male broiler chicks were randomly assigned into five treatments with six replicates of 20 birds each for 35 days. Treatments consisted of five experimental diets containing 0 (control), 3, 5, 10, or 15% canola meal (CM). Final body weight (BW) was not affected by the dietary treatments. Daily BW gain (DWG) and feed intake linearly decreased as dietary CM inclusion increased during the starter phase (p<0.0001), but not during the grower and total rearing periods. Chicks fed the diet with 15% CM presented the lowest DWG during the starter phase. Breast meat yield of CM-fed chicks linearly decreased as CM inclusion level increased (p=0.0014). Dietary CM supplementation did not influence organ relative weights, except for the spleen, meat quality, or blood profile. The results suggest that the CM may replace soybean meal (SBM) with no detrimental effects on overall growth performance or physiological responses of broiler chickens. However, it is recommended that supplementing excess amount of CM into broilers' diet should be taken into account in practical diet formulation as it could impair growth performance at early age and lower breast meat yields.