Effect of an Escherichia coli-derived phytase and a carbohydrase-protease cocktail derived from Bacillus spp. on performance, digestibility, bone mineralization and gut morphology in broilers fed different nutrient density diets.

BACKGROUND: Enzyme combinations, particularly phytase (PHY) with various carbohydrases and proteases, are utilized in commercial broiler production to enhance nutrient and energy bioavailability. OBJECTIVE: A feeding study was undertaken to determine whether the efficiency of an Escherichia coli-derived PHY and a feed enzyme complex (FEC) derived from Bacillus spp. containing carbohydrase and protease as main activities in broiler chickens is dependent on diet quality. A total of 900 male one-day-old broiler chickens (Ross 308) were assigned to a 2 × 3 factorial arrangement of the treatments with 2 different nutrient density diets, standard nutrient diet (SN diet) and a low-nutrient diet (LN diet; -100 kcal/kg for AMEn and -5% for crude protein [CP] and limiting amino acids), and 3 enzyme treatments (control [no enzymes], PHY and PHY + FEC). Each treatment group was composed of 6 replicates of 25 birds each. RESULTS: The LN diet caused a decrease in performance index, tibia length and diameter, tibia calcium content and jejunal villus surface area (VSA). The interaction effects between diet and enzyme supplementation were observed (p < 0.05) on overall average daily gain (ADG), performance index, tibia ash content and jejunal villus height (VH) and VSA, with the favourable benefits of PHY + FEC treatment being more pronounced in the LN diets. Regardless of dietary nutrient density, supplementation with PHY alone or combined with FEC enhanced (p < 0.05) final body weight, overall ADG and jejunal villus height (VH)/crypt depth, with the highest values observed in the PHY + FEC group. The PHY + FEC treatment also improved (p < 0.05) overall feed conversion ratio, apparent ileal digestibility of dry matter, organic matter, CP, and energy, and tibia phosphorus content compared to the control treatment. CONCLUSIONS: The results indicate that the simultaneous addition of PHY and FEC to the LN diets improved the growth rate, bone mineralization and gut morphology.

Effect of guanidinoacetic acid on performance, egg quality, yolk fatty acid composition, and nutrient digestibility of aged laying hens fed diets with varying substitution levels of corn with low-tannin sorghum.

A study was conducted to evaluate the efficiency of guanidinoacetic acid (GAA) in diets containing varying levels of corn replacement with low-tannin sorghum (LTS) for laying hens in the later stage of production. In a 12-wk study, a total of 288 laying hens at 52 wk of age were divided into 6 treatment groups. Each treatment group had 8 replicates, each of which consisted of 6 hens. A 2 × 3 factorial design was used to investigate the impact of substituting corn with LTS at 3 levels (100% corn, 50% LTS, and 100% LTS) with 2 doses of GAA supplementation (0 and 0.6 g/kg). The results indicate that there were interaction effects (P < 0.05) between diet type and GAA supplementation on protein digestibility and AMEn, with the GAA supplement being more effective in the 100% LTS group. Replacing corn with LTS at both levels had no negative effects on performance and metabolic profile. In contrast, the 100% LTS diet increased monounsaturated fatty acids in the yolk (P < 0.05), but decreased the yolk color index, the ratio of polyunsaturated fatty acids (PUFA) to saturated fatty acids (SFA) in the yolk, ileal digestibility of energy, and AMEn when compared to the 100% corn diet (P < 0.05). Regardless of the diet, dietary supplementation with GAA resulted in increases (P < 0.05) in shell-breaking strength, the PUFA to SFA ratio in egg yolk, and concentrations of creatine and nitric oxide in serum. There was also a decrease (P < 0.05) in serum malondialdehyde concentration with GAA supplementation. In conclusion, the positive effects of GAA on protein digestibility and AMEn were found to be more pronounced when corn was completely replaced with LTS. However, the positive effects of GAA on egg-laying performance, eggshell quality, antioxidant status, and yolk fatty acid composition remained consistent regardless of the extent to which corn was substituted with LTS.

Effects of low eggshell temperatures during incubation, in ovo feeding of L-arginine, and post-hatch dietary guanidinoacetic acid on hatching traits, performance, and physiological responses of broilers reared at low ambient temperature.

This study aimed to investigate the effect of eggshell temperature (ET) manipulations during incubation, in ovo feeding (IOF) of arginine, and post-hatch dietary supplementation with guanidinoacetic acid (GAA) on hatching traits and subsequent growth and physiological performance of hatched broiler chicks reared under subnormal temperature. In experiment 1, from d 8 of incubation onward, a total of 2,160 hatching eggs were randomly arranged in a 2 × 3 factorial design, in which the eggs were exposed to 2 ET (37.8°C or periodically low ET), and 3 IOF treatments (noninjected, diluent-injected, and 1% arginine solution-injected). In experiment 2, a total of 576 one-day-old male broiler chicks from 2 temperature conditions and 2 IOF treatment groups (noninjected and Arg-injected) were reared for 42 d with or without GAA supplementation in a 2 × 2 × 2 factorial design. Each treatment had 6 replicates with 12 birds each. A subnormal ambient temperature (17°C) was applied from 15 d onward to induce ascites. Results from experiment 1 showed a 2-way interaction between ET and IOF for embryonic mortality rate during 19 to 21 d of incubation and residual yolk weight at hatch (P < 0.05). A periodically low ET significantly increased yolk free body mass, first-grade chicks, and relative heart weight than an ET of 37.8°C. In the second experiment, overall average daily gain (ADG) was increased, but feed conversion ratio (FCR), ascites mortality, and serum thyroid hormones and corticosterone were reduced in the low ET group (P < 0.05). There were also IOF × GAA interactions for ADG and FCR (P < 0.05). IOF of arginine or dietary GAA increased serum nitric oxide concentration and jejunal villus height, but decreased ascites mortality (P < 0.05). In conclusion, a periodically low ET accompanied by IOF of arginine during incubation and posthatch dietary supplementation with GAA could be a useful strategy for improving the chick quality at hatch and subsequent improvements in post-hatch performance and ascites indices in cold-stressed broilers.

Effect of advanced chelate compounds-based mineral supplement in laying hen diet on the performance, egg quality, yolk mineral content, fatty acid composition, and oxidative status.

The study aimed to determine the efficiency of advanced chelate compounds-based trace minerals (OTM) in laying hens. Laying hens (240, 32 weeks old) were assigned to one of the following five groups: NOTM (no added trace minerals), CONTM (standard mineral salts), and three experimental groups in which chelates were used to replace 33, 66, and 100% of mineral salts (OTM33, OTM66, and OTM100, respectively). Each treatment had six replicates with eight hens per replicate. After 18 weeks, performance and physicochemical properties of eggs in all experimental groups was better than those in the NOTM group. Among the treatments, OTM66 and OTM100 produced the best results in terms of laying performance, yolk PUFA/SFA ratio, Zn and Se contents, and malondialdehyde concentration in both serum and yolk. In conclusion, up to 66% OTM supplementation was beneficial for performance, lipid and mineral composition of yolk, and oxidative status.

Effects of multicarbohydrase and butyrate glycerides on productive performance, nutrient digestibility, gut morphology, and ileal microbiota in late-phase laying hens fed corn- or wheat-based diets.

A study was undertaken to determine the effects of supplemental multicarbohydrase (MC) and butyrate glycerides (BG) on productive performance, nutritional, and physiological responses in laying hens fed corn- or wheat-based diets during a 12-week production period (from 50-62 wk of age). The experiment consisted of a 2 × 2 × 2 factorial arrangement of the treatments with 2 different basal diets (corn- or wheat-based diets), 2 concentrations of MC (0 or 200 mg/kg of diet), and 2 concentrations of BG (0 or 2 g/kg of diet). Each treatment had 6 replicates with 8 hens each. The interactions among diet, MC, and BG were observed for egg production (P = 0.048), feed conversion ratio (P = 0.005), and ileal Escherichia coli count (P = 0.043), indicating that the effects of MC and BG on these responses were more marked when wheat-based diet was fed. A diet × MC interaction (P < 0.05) was also detected for egg mass, eggshell breaking strength, jejunal viscosity, and digestibility coefficients of fat and ash. Replacing 100% of the corn with wheat in the diets of laying hens negatively affected (P < 0.05) yolk color index, eggshell thickness, digesta viscosity, jejunal morphology, and populations of ileal microbiota. By contrast, MC supplementation increased (P < 0.05) eggshell thickness, digestibility coefficients of energy and crude protein, and populations of Lactobacillus and Bifidobacterium spp. in the ileum. Inclusion of BG also resulted in greater (P < 0.05) jejunal villus height and villus surface area, and digestibility coefficients of protein and ash, but lower (P < 0.05) populations of total bacteria, Salmonella and E. coli in the ileum. Results indicate that while the complete substitution of corn by wheat has a detrimental effect on productive performance and gut health, the combination of MC and BG may have synergistic effects on improving productive performance and intestinal microbiota in laying hens fed the wheat-based diets during the late laying period.

Effect of advanced chelate technology based trace minerals on growth performance, mineral digestibility, tibia characteristics, and antioxidant status in broiler chickens.

BACKGROUND: Compared to the corresponding source of inorganic trace minerals (TM), chelated supplements are characterized by better physical heterogeneity and chemical stability and appear to be better absorbed in the gut due to possibly decreased interaction with other feed components. METHODS: This study was designed in broiler chickens to determine the effects of replacing inorganic trace minerals (TM) with an advanced chelate technology based supplement (Bonzachicken) on growth performance, mineral digestibility, tibia bone quality, and antioxidant status. A total of 625 male 1-day-old broiler chickens were allocated to 25 pens and assigned to 5 dietary treatments in a completely randomized design. Chelated TM (CTM) supplement was compared at 3 levels to no TM (NTM) or inorganic TM. A corn-soy-based control diet was supplemented with inorganic TM at the commercially recommended levels (ITM), i.e., iron, zinc, manganese, copper, selenium, iodine, and chromium at 80, 92, 100, 16, 0.3, 1.2, and 0.1 mg/kg, respectively, and varying concentration of CTM, i.e., match to 25, 50, and 100% of the ITM (diets CTM25, CTM50, and CTM100, respectively). RESULTS: Diets CTM50 and CTM100 increased average daily gain (ADG), European performance index (EPI), and tibia length compared to the NTM diet (P < 0.05). Broilers fed the CTM100 diet had lowest overall FCR and serum malondialdehyde level and highest EPI, tibia ash, zinc, manganese, and copper contents, and serum total antioxidant capacity (P < 0.05). The apparent ileal digestibilities of phosphorus and zinc were lower in the ITM group compared with the CTM25 and CTM50 groups (P < 0.05). Broiler chickens fed any of the diets, except diet CTM25, exhibited higher serum glutathione peroxidase and superoxide dismutase activities than those fed the NTM diet, where the best glutathione peroxidase activity was found for CTM100 treatment (P < 0.05). CONCLUSIONS: These results indicate that while CTM supplementation to 25 and 50% of the commercially recommended levels could support growth performance, bone mineralization, and antioxidant status, a totally replacing ITM by equivalent levels of CTM could also improve performance index and glutathione peroxidase activity of broiler chickens under the conditions of this study.

Nutritional and physiological responses of broiler chickens to dietary supplementation with de-oiled soyabean lecithin at different metabolisable energy levels and various fat sources.

A 42-d study was conducted to investigate the effects of an emulsifier supplementation (de-oiled soyabean lecithin (DSL)) of diets with different levels of metabolisable energy (ME) and various sources of fat on growth performance, nutrient digestibility, blood profile and jejunal morphology of broiler chickens. Diets were arranged factorially (2 × 2 × 2) and consisted of two concentrations of ME (normal and low), two fat sources (soyabean oil (SO) and poultry fat (PF)) and two levels of DSL supplementation (0 and 1 g/kg). A total of 800 1-d-old male broiler chickens were assigned to eight treatments with five replicates/treatment. The results showed the supplemental DSL caused improvements in the overall feed conversion ratio, fat digestibility and jejunal villus height:crypt depth ratio, but the magnitude of the responses was greater in the PF-containing diets, resulting in significant fat × DSL interactions (P<0·05). Abdominal fat percentage was also reduced by the PF-containing diet, but the response was greater in the normal ME diet, resulting in a significant ME × fat interaction (P = 0·048). Dietary DSL supplementation also increased nitrogen-corrected apparent ME values but decreased blood TAG (P = 0·041) and LDL (P = 0·049) concentrations, regardless of the source of fat used or the ME values in the diet. In conclusion, the present study suggests that the improvements in growth performance, fat digestibility and intestinal morphology that can be achieved with DSL supplementation are highly dependent on the degree of saturation of lipid incorporated into broiler chicken diets.

Effects of water supplementation of an organic acid-trace mineral complex on production and slaughter parameters, intestinal histomorphology, and macronutrient digestibility in growing ostriches.

An experiment was conducted to study the effect of water supplementation of organic acid-chelated trace minerals (OTM) on production traits, carcass characteristics, intestinal histomorphology, and nutrient digestibility in African ostrich chicks from 8 to 12 mo of age. A total of 20 growing ostriches, with almost similar body weight (73.4 to 75.8 kg), were individually distributed in outdoor paddocks of ≈ 24 m2 and were randomly allocated into 1 of the following 4 treatments: (1) control/basal diet, (2) low OTM (basal diet + 100 mg/bird/day OTM powder in water), (3) medium OTM (basal diet + 1 g/bird/day OTM powder in water), and (4) high OTM (basal diet + 2 g/bird/day OTM powder in water). The body weight gain and feed conversion efficiency were greater (P < 0.05) in ostriches receiving medium-OTM treatment compared to control during the overall phase of the experiment. Although whole carcass yield, the yield of parts, and the relative weights of internal organs were not affected by experimental treatments, supplementation of higher amounts of OTM (medium- and high-OTM) resulted in a decrease (P < 0.05) in the subcutaneous and abdominal fat contents. Medium- and high-OTM treatments increased (P < 0.05) the villus height/crypt depth ratio in the jejunum and ileum compared with control and low-OTM treatments. Moreover, ostriches receiving the medium-OTM had also higher total tract apparent digestibility of energy (P = 0.048), ether extract (P = 0.050), crude fiber (P = 0.063), and higher AMEn (P = 0.094) than the control group. Overall, supplementation of OTM at the level of 1 g/bird/day to the drinking water of growing ostriches fed diets containing the recommended levels of inorganic trace minerals could beneficially affect productive performance, nutrient digestibility, and intestinal morphology.

Growth Performance, Mineral Digestibility, and Blood Characteristics of Ostriches Receiving Drinking Water Supplemented with Varying Levels of Chelated Trace Mineral Complex.

The effects of water supplementation of chelated trace minerals (CTM, which is named Bonzaplex designed with chelate compounds technology) on growth performance, apparent total tract digestibility (ATTD) of minerals, and some blood metabolites, TM, and antioxidant enzyme values in African ostriches were investigated from 8 to 12 months of age. A total of 20 8-month-old ostriches (five birds in five replicate pens) was randomly allocated into one of the following four treatments: (1) control (basal diet + tap water), (2) low CTM (basal diet +100 mg/bird/day CTM powder in tap water), (3) medium CTM (basal diet +1 g/bird/day CTM powder in tap water), and (4) high CTM (basal diet +2 g/bird/day CTM powder in tap water). Compared with control, medium CTM improved (P < 0.05) daily weight gain and ATTD of phosphorous, zinc, and copper in 12-month-old ostriches. Furthermore, the feed conversion ratio was lower, and ATTD of magnesium was higher in the medium- and high-CTM groups than that in the control group (P < 0.05). At the end of the trial, ostriches receiving high-CTM treatment exhibited the lower (P < 0.05) serum triglyceride and very low-density lipoprotein cholesterol concentrations and higher copper levels compared to those of the control treatment. Supplementation of higher amounts of CTM (medium and high CTM) also increased the activity of serum superoxide dismutase (P < 0.05). No differences were detected for other blood parameters including glucose, total protein, albumin, cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, iron, magnesium, and glutathione peroxidase values. In conclusion, supplementation of CTM at the level of 1 g/bird/day to the drinking water can be recommended for improving growth performance, mineral absorption, and antioxidant status of ostriches fed diets containing the recommended levels of inorganic TM.