A Novel Bacterial 6-Phytase Improves Growth Performance, Tibia Mineralization and Precaecal Digestibility of Phosphorus in Broilers: Data from Four Independent Performance Trials

A series of four broiler performance studies were conducted in different facilities to investigate the efficacy of a novel bacterial 6-phytase added at 500 FTU/kg diet on growth performance, bone mineralization and precaecal digestibility of phosphorus (pcdP) in broilers fed diets deficient in available P (avP) and calcium (Ca). The experimental design was the same for all studies, with each having three treatments: positive control (PC) diet formulated to meet or exceed the requirements of birds, negative control (NC) diet similarly reduced by 0.15% points in avP and Ca compared to the PC diet, and the NC diet supplemented with phytase (PHY) at 500 FTU/kg diet from 1 to 35 days of age. Body weight (BW) and feed intake were measured at 21 and 35 days of age, and average daily gain (ADG), average daily feed intake (ADFI), feed conversion ratio (FCR), BW gain-corrected-FCR (cFCR), mortality and European performance efficiency factor (EPEF) were calculated. Tibia dry matter, tibia ash content and pcd of P were measured at 21 days of age in all experiments. The analysis of the data from the four experiments showed that compared with birds fed the adequate-nutrient diet, birds fed the NC diet resulted in a decrease (p < 0.05) in BW, ADG, ADFI and EPEF by 6.4, 6.3, 5.9 and 7.1%, respectively, and an increase in (p = 0.02) cFCR by 2.0%. The tibia dry matter and tibia ash content of these birds were also reduced (p < 0.001) by 3.8 and 4.0% points, respectively. PHY diets improved (p < 0.05) BW, ADG, ADFI, EPEF and cFCR by 8.0, 8.3, 7.3, 10.6 and 2.8%, respectively. Phytase addition at 500 FTU/kg diet also increased (p < 0.001) the tibia dry matter and tibia ash content by 3.5 and 4.2% points, respectively. The pcd of P was improved (p < 0.001) by 11.1 and 11.3% points, in comparison with NC and PC diets, respectively, when phytase was added. These performance parameters and tibia mineralization obtained with a diet supplemented with phytase were comparable to or better than the PC diet. The results demonstrated that avP and Ca could be lowered similarly by 0.15% points in broilers diets by using the new bacterial 6-phytase at 500 FTU/kg diet.info:eu-repo/semantics/publishedVersio

Bio-efficacy of hydroxy-selenomethionine as a selenium supplement in pregnant dairy heifers and on the selenium status of their calves

This study aimed to determine the effects of supplementing pregnant heifers with the organic selenium source 2-hydroxy-4-methylselenobutanoic acid (HMSeBA) during last eight weeks of pregnancy on dam and calf Se status. A total of 42 in-calf heifers were recruited to the study and randomly allocated to one of three treatments; a negative control (Con), sodium selenite (NaSe) or HMSeBA. Animals were blocked by body weight, body condition score, and expected calving date prior to treatment allocation. Following enrollment all animals underwent a seven week wash-out period after which they received their respective supplements, topped dressed daily onto a basal diet for the last eight weeks of pregnancy. Heifer blood samples were taken at weekly intervals from enrollment until two weeks before expected calving date, and as soon as possible after calving for determination of whole blood glutathione peroxidase activity (GSH-Px) and plasma selenium (Se) and malondealdehyde (MDA) concentrations. Selenized amino acids were determined in plasma samples taken at three weeks pre-calving. A colostrum sample was taken as close to parturition as possible for determination of colostrum total Se, selenized amino acid, and Immunoglobulin G (IgG) concentration. Calves were blood sampled as close to birth as possible for determination of whole blood GSH-Px activity and plasma Se and MDA concentration. Differences in whole blood GSH-Px activity did not become apparent until calving; GSH-Px activity was lowest in Con heifers (P < 0.05) but similar between NaSe and HMSeBA. Plasma Se was lowest in unsupplemented heifers and greatest in those supplemented with HMSeBA (P < 0.001) and this was attributable to greater selenomethionine concentrations in the plasma of HMSeBA heifers (P < 0.01). Colostrum Se was lowest in Con heifers and greatest in HMSeBA (P < 0.001), the greater Se concentration of HMSeBA heifers was attributable to a greater proportion of total Se comprising selenocysteine (P = 0.061), the reason for this is not known. There was no effect of supplementation on colostrum IgG concentration. Plasma Se was lowest in those calves born to Con heifers and greatest in those born to HMSeBA heifers (P < 0.001). There were no effects of treatment on calf whole blood GSH-Px activity or plasma MDA concentration. The enhanced Se status associated with HMSeBA supplementation is likely a consequence of selenomethionine supply and may confer benefits to both the dam and her calf post-partum

Evaluation of phytase dose effect on performance, bone mineralization, and prececal phosphorus digestibility in broilers fed diets with varying metabolizable energy, digestible amino acids, and available phosphorus concentration

ABSTRACT: The nutritional composition of diets and the provision of exogenous phytases play important roles in animal performance. Therefore, we evaluated the individual and combined impact of metabolizable energy (ME), digestible lysine (dLys), available phosphorus (avP) and calcium (Ca), and phytase dose (1,000 or 2,000 FTU/kg) on the growth performance, feed efficiency, phosphorus digestibility, and bone ash content of broiler chickens from 10 to 42 d of age. Experimental diets were formulated in a Box-Behnken design to contain various levels of ME (11.9, 12.2, 12.54, or 13.1 MJ/kg), dLys (0.91, 0.93, 0.96, or 1.00%) and avP/Ca (0.12/0.47, 0.21/0.58, or 0.33/0.68%). The effect of phytase was expressed in terms of the extra nutrients released. The diets were formulated to have consistent phytate substrate contents (0.28% in average). Body weight gain (BWG) and feed conversion ratio (FCR) were described via polynomial equations (R2 = 0.88 and 0.52, respectively), with interconnections between variables (ME, dLys, and avP/Ca). No interaction was observed among variables (P > 0.05). Metabolizable energy was the most important factor affecting BWG and FCR (linearly; P < 0.001). Reducing ME content from 13.1 to 11.9 MJ/kg in control diet resulted in a 6.8% decrease in BWG and a 3.1% increase in FCR (P < 0.001). The dLys contents also affected performance linearly (P < 0.001), but to a lesser degree; BWG decreased by 160 g when the dLys was reduced by 0.09% units, while the same reduction in dLys increased the FCR by 0.108 points. The inclusion of phytase alleviated the negative effects on feed intake (FI), BWG, and FCR. Phytase improved phosphorus digestibility and bone ash content according to a quadratic relationship. When phytase was added, ME negatively affected FI (r = −0.82, P < 0.001), whereas the dLys content was correlated with FCR (r = −0.80, P < 0.001). Supplementing phytase allowed the reduction of ME, dLys, and avP–Ca in the diet without affecting performance. The addition of phytase increased of ME, dLys, and avP by 0.20 MJ/kg, 0.04 and 0.18% units for 1,000 FTU/kg and 0.4 MJ/kg, 0.06 and 0.20% units for 2,000 FTU/kg

Dietary metabolizable energy, digestible lysine, available phosphorus levels and exogenous enzymes affect broiler chicken performance

The nutritional composition of diets and the provision of exogenous enzymes play important roles in animal performance. Here, we evaluated the individual and combined impact of nutrients (metabolizable energy (ME), digestible lysine (dLys), available phosphorus and calcium (avP–Ca)) and exogenous multicarbohydrase and phytase complex (MCPC) enyzmes on the growth performance and feed efficiency of broiler chickens from 10 to 42 days (d) of age. Experimental diets were formulated in a Box-Behnken design to contain various levels of ME (11.89, 12.21, 12.54 or 13.06 MJ/kg), dLys (0.91%, 0.93%, 0.96% or 1.00%) and avP/Ca (0.12/0.47%, 0.21/0.58% or 0.33/0.68%). The effect of MCPC was expressed in terms of the extra nutrients released. The diets were formulated to have consistent substrate contents (i.e., arabinoxylan and phytate). Feed intake (FI), BW gain (BWG) and feed conversion ratio (FCR) were described via polynomial equations (R2 = 0.99, 0.98 and 0.81, respectively), with interconnections between variables (ME, dLys and avP–Ca). Available P–Ca was the most important factor affecting FI (quadratically), and BWG and FCR (linearly). Reducing the avP content from 0.33% to 0.12% in diets lacking MCPC resulted in 25% and 33% decreases in FI and BWG, respectively, and a 12% increase in FCR. The ME and dLys contents also linearly affected these performance parameters to a lesser degree; FI decreased by 400 g when the ME was reduced by 1.17 MJ/kg, and by 300 g following a 0.09% reduction of dLys, while the same reductions in ME and dLys decreased BWG by 120 g and 150 g, respectively. The inclusion of MCPC alleviated the reduction of FI, BWG and FCR by decreasing the avP–Ca. Thus, ME and dLys were the most important factors affecting BWG and FCR in broilers fed diets containing MCPC. When MCPC was added, ME negatively affected FI (r = −0.89, P < 0.001), whereas the dLys content was correlated with BWG (r = 0.74, P < 0.001). Both ME and dLys affected FCR (r = −0.83 and −0.85, respectively). Supplementing MCPC allowed the reduction of ME, dLys and avP–Ca in the diet without affecting performance. Indeed, MCPC’s effect promoted with the release of the following nutrients: 0.56 MJ ME/kg, 0.06% dLys, and 0.15% and 0.13% avP and Ca, respectively. The results indicate nutrient effect and interaction on performance and feed additive potential for nutrient release