Effect of phytase supplementation on performance, fecal excretion, and compost characteristics in broilers fed diets deficient in phosphorus and calcium.

This study investigated the effect of dietary supplementation with phytase on growth performance, fecal excretion, and compost nutrition on broilers fed available phosphorus (avP)- and calcium (Ca)-deficient diets. A total of 750 one-day-old broiler chicks were randomly divided into five dietary groups having ten replications in a floor house. Diets of the groups were formulated with positive control (PC), negative control (NC; low avP and Ca), and NC supplemented with phytase levels; 500 (NC500), 1,000 (NC1000), and 1,500 FTU/kg (NC1500). A three-phase feeding program was used in the trial. Average daily gain (ADG) and average daily feed intake (ADFI) in the groups fed diets supplemented with phytase were significantly (p < 0.05) higher than those fed NC and the increase was equivalent to those fed PC. Serum levels of Ca and phosphorus (P) were higher (p < 0.05) in broilers fed NC1000 and NC1500 than in those fed NC. Interleukin (IL) level was the lowest in the group fed NC. Plasma myo-inositol (INS) concentrations in the NC1500 group were higher (p < 0.05) than PC, NC, and NC500 groups. Crude protein (CP) excretion was notably (p < 0.05) lower in the NC1500 group than in PC and NC groups. A lower (p < 0.05) concentration of P2O5 was observed in compost from the group fed NC1500 than the groups fed PC and NC. Accordingly, we suggest that phytase supplementation in lower avP and Ca levels of broiler diet can improve their productive performance and reduce environmental pollution.

Cold Drinking Water Boosts the Cellular and Humoral Immunity in Heat-Exposed Laying Hens.

This study aimed to investigate the effects of cold drinking water on cellular and humoral immunity in heat-exposed laying hens. One hundred and eight laying hens at 19 weeks old were placed into three treatments with six replicates of six hens in each group as follows: (1) hens were provided with normal drinking water (NW) under the control of thermoneutral temperature (CT: 25 ± 1 °C; CT + NW), (2) hens were provided with NW under high ambient temperature (HT: 35 ± 1 °C; HT + NW) for 8 h/d for a month, and (3) hens were treated under HT with cold drinking water (CW: 15 ± 1 °C; HT + CW) for 8 h/d for a 4-weeks. Then, the feed consumption, egg production, egg weight, feed conversion ratio, and blood immune parameters were investigated. The results showed that cold drinking water (CW) caused a significant (p < 0.05) recovery in the reduction of food intake and egg production due to heat stress; however, there was no significant effect (p > 0.05) on egg weight and feed conversion ratio. Moreover, CW significantly (p < 0.05) restored the immune-suppressing effects of heat stress on the contents of peripheral blood mononuclear cells, including B-cell (BU-Ia), helper T cell (CD4), and the ratio of helper/cytotoxic T cell (CD4/CD8). In addition, CW significantly (p < 0.05) recovered the reduction on the level of mRNA expression of interleukin-2 (IL-2) and interferon-gamma (IFN-γ), as well as significantly (p < 0.05) restored the reduction of plasma concentration of IL-2, IFN-γ and immunoglobulin G in heat-stressed laying hens. These results prove that CW increased heat dissipation and enhanced feed intake, egg production, and cellular and humoral immunity in heat-exposed laying hens.

Additive Effects of Dietary Supplementation with Zeolite and Methyl-Sulfonyl-Methane on Growth Performance and Interleukin Levels of Broiler Chickens.

Silicate minerals are common additives in poultry feed. To assess their effects, we added zeolite (ZEO) and methyl-sulfonyl-methane (MSM) to broiler chicken diets. A total of 960 one-day-old Ross broiler chicks were randomly divided into four dietary groups with six replicates. Each broiler was maintained until it reached 35 days of age. A completely randomized 2 × 2 experimental design was used, with two ZEO (0 and 1.0%) and two MSM (0 and 0.10%) levels. We observed an additive effect (P<0.05) on interleukin-2 (IL-2) concentrations in broiler bursa and serum when both ZEO and MSM were present. Both ZEO or MSM produced significant (P<0.05) increases in body weight, weight gain, and feed intake. Both increased IL-2 and IL-6 levels in the bursa and serum. Neither affected the serum concentrations of albumin, AST, cholesterol, HDL cholesterol, glucose, total protein, or triglycerides. In summary, these results support supplementation with ZEO and MSM in broiler diets, both separately and in combination.

Interactive effects of dietary supplementation between illite and probiotic on productive performance, intestinal microflora, and blood profiles of laying hens.

This study investigates the interactive effects of dietary illite and probiotic on productive performance, intestinal microflora, and blood profiles of laying hens. A total of 432 laying hens at 24 weeks old were allotted into six dietary groups. An experimental design was composed with a 3 (illite levels: 0, 0.3, and 0.6%) × 2 (probiotic levels: 0 and 0.2%). The probiotic based on Bacillus subtilis, Saccharomyces cerevisiae, and B. licheniformis was used. There were interactions between illite and probiotic on total microbes and salmonella of digesta. Higher egg production was observed in hens fed a diet supplemented with either 0.6% illite or 0.2% probiotic than in those fed a basal diet. The total microbes of the group fed a diet with 0.6% illite were lower than the groups fed diets with 0 and 0.3% illite. A lower number of Escherichia coli was observed in hens fed a diet with probiotic than those fed a basal diet. Higher immunoglobulin G concentration was observed in the group fed a diet supplemented with 0.6% illite than in those fed a basal diet. Our results suggest illite and probiotic can be used as feed additives for hens, separately or in combination to improve performance and intestinal microflora.

Effect of dietary octacosanol concentration extracted from triticale sprout on laying performance, egg quality, and blood parameters of laying hens.

This study was conducted to investigate the effect of dietary supplementation of octacosanol (OCT) extracted from triticale sprout on laying performance, egg quality, and blood parameters of laying hens. A total of 192, Hyline brown laying hens aged 43 weeks were divided into 4 dietary groups of 48 birds each and they were randomly subjected to one of the experimental diets containing OCT at the levels of none, 10, 20, and 30 mg/kg of diet. All birds were fed with isoenergetic and isonitrogenous mash diets for 6 weeks. The result showed that hens supplemented with 20 and 30 mg/kg OCT in diet significantly increased (p < 0.05) egg production than those fed with the basal diet. OCT concentration in the egg yolk of hens fed with 20 and 30 mg/kg OCT was significantly higher than in those fed the control diet. Hens fed 20 and 30 mg/kg OCT exhibited greater high-density lipoprotein (HDL) cholesterol and interleukin (IL) concentrations and reduced serum concentrations of cholesterol and triglyceride compared to those fed with 0 and 10 mg/kg OCT. This study indicates that supplementing the diet of laying hens with 20 and 30 mg/kg of OCT can improve the performance, egg quality, and health status of laying hens.

Interactive effect of dietary levels of calcium and 25-hydroxy vitamin D3 on the performance, serum biochemical concentration and digestibility of laying hens from 61 to 70 weeks of age.

OBJECTIVE: The present research was conducted to evaluate the interactive effect of dietary concentration of calcium (Ca) and 25-hydroxy vitamin D3 (25OHD3) on the performance, blood composition and digestibility of laying hens. METHODS: A total of 540 Hy-line brown laying hens aged 61 to 70 weeks were randomly allotted in a 3×3 factorial arrangement, consisting of three levels of 25OHD3 (0, 25, and 50 µg/kg) and three levels of Ca (3.5%, 4.0%, and 4.5%). All diets had basal concentration of 3,000 IU/kg of vitamin D3 including the 2,800 kcal/kg of metabolic energy and 16% of crude protein. RESULTS: The results showed that interactive effect (p<0.05) between Ca and 25OHD3 was such that dietary 25OHD3 linearly increased interleukin-6 at all levels of Ca inclusion. Interaction (p<0.05) occurred with the highest parathyroid hormone in laying hens that received dietary concentration of Ca (3.5%) with 25OHD3 (50 µg/kg), and Ca (4.0%) with 25OHD3 (50 µg/kg). Egg production and egg weight significantly (p<0.05) increased in the 4.5% Ca group compared to the 3.5% to 4.0% Ca groups. Egg shell thickness and tibia bone length also increased (p<0.05) in groups fed a high-Ca diet (4.0% to 4.5%). Phosphorus digestibility significantly (p<0.05) increased along with dietary Ca level. Among the tested 25OHD3 groups, higher (p<0.05) egg production and tibia thickness were present in hens fed 50 µg/kg of 25OHD3. Furthermore, Ca digestibility serum Ca and 25OHD3 were significantly increased in group offered 50 µg/kg of 25OHD3. CONCLUSION: The results gathered in this study indicate that dietary concentrations of 4.0% to 4.5% Ca and 50 µg/kg 25OHD3 improve the performance of hens from 61 to 70 weeks of age.