A Novel Bacterial 6-Phytase Improves Productive Performance, Precaecal Digestibility of Phosphorus, and Bone Mineralization in Laying Hens Fed a Corn-Soybean Meal Diet Low in Calcium and Available Phosphorus

Exogenous phytases are commonly added to low-phosphorus and low-calcium diets to improve P availability and reduce P excretion by poultry. This study investigated the effect of supplementation with a novel bacterial 6-phytase on egg production, egg quality, bone mineralization, and precaecal digestibility of P in laying hens fed corn-soybean meal-based diets. A total of 576 Hy-Line brown laying hens were used in a completely randomized block design at 25–45 weeks of age (woa). The three treatments included a positive control (PC) adequate-nutrient diet with 2840 kcal metabolizable energy/kg, 0.77% digestible lysine, 3.5% Ca, and 0.30% available P (avP); a negative control (NC) diet with 0.16% points less Ca and avP; and an NC diet supplemented with a novel bacterial 6-phytase at 300 phytase units/kg diet. Hen performance and the percentage of damaged eggs were measured every 4 weeks. Body weight, precaecal digestibility of P, and bone parameters at 45 woa were also measured. The reduction in avP and Ca in the NC diet did not compromise performance or egg quality. However, it decreased (P < 0.001) body weight, tibial dry matter, tibial ash and P content, and precaecal digestibility of P. Importantly, all these parameters were significantly improved (P < 0.001) and essentially restored to the levels measured in PC diet-fed hens upon supplementation with phytase. In summary, the present study demonstrates that the new bacterial 6-phytase could effectively counteract the negative effects of P and Ca deficiencies on body weight, bone mineralization, and P availability, thereby supporting high productivity without compromising the welfare of laying hens.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

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

Effect of pomegranate (Punica granatum L) peel powder meal dietary supplementation on antioxidant status and quality of breast meat in broilers

This study examined the antioxidant status and quality of breast meat in broiler birds fed diets supplemented with pomegranate peel powder meal (PPPM). During the 35-d feeding trial, broiler birds were fed six experimental diets: diet with 0% additives (negative control; NEGCON); diet with α-Tocopherol acetate at 200 g/tonne (positive control; POSCON); and four levels (2, 4, 6 and 8 g/kg) of PPPM, designated as PPPM2, PPPM4, PPPM6, and PPPM8. Breast muscle pH was determined 15mins and 24hrs postmortem. The breast muscles were then stored at 4 °C to determine shelf-life attributes (pH, colour, hue angle, and chroma) for 16 days. Meat from the 8 g/kg PPPM had the highest thawing loss, whereas cooking loss was lowest at 2 g/kg PPPM inclusion. The meat of birds fed 2 g/kg and 4 g/kg PPPM had the highest (P<0.05) ability to scavenge the ABTS [(2, 2-azinobis (3ethylbenzothiazoline-6 sulfonic acid))] radical cation (ABTS+), whereas, catalase activity was increased at 8 g/kg PPPM. The results obtained in this study indicate that 2 g/kg supplementation of pomegranate peel powder meal significantly improved the water-binding capacity of broiler breast meat, owing to the reduced cooking loss of the meat, and meat from the PPPM2 (2 g/kg) group had the highest ability to scavenge ABTS

Study the molecular mechanisms involved in meat quality variation in poultry

Plusieurs acteurs moléculaires impliqués dans les variations de qualité de la viande ont été récemment mis en évidence chez le poulet. Ma thèse a pour objectif d’approfondir l’étude de leur régulation en étudiant l’impact de facteurs alimentaires en interaction avec l’origine génétique des animaux. Il s’est articulé autour de deux thématiques qui impliquent des acteurs moléculaires et des critères de qualité de viande indépendants : le rôle de l’AMPK (AMP-activated protein kinase) dans le contrôle du turnover du glycogène musculaire et des caractères qui en dépendent (pH, rétention d’eau, couleur) et l’implication de BCMO1 (β, β-carotene-15,15’-monooxygenase) dans les variations de teneurs en pigments caroténoïdes et de coloration. Nos résultats soulignent dans les deux cas la possibilité de moduler les caractères de qualité via l’alimentation avec des réponses qui dépendent des caractéristiques génétiques des animaux. Nos travaux ont aussi permis d’améliorer la compréhension de la régulation des biomarqueurs étudiés par les nutriments et la génétique et contribueront à terme à la mise en place de nouvelles stratégies de production permettant d’optimiser la qualité du poulet de chair en réponse aux attentes de la filière et des consommateurs.Several molecular mechanisms involved in the variations of poultry meat quality were recently identified in chickens. My thesis aims to further study their regulation by exploring the impact of dietary factors in interaction with the genetic origin of animals. It was structured around two themes that involve independent molecular mechanisms and meat quality criteria: the role of AMPK (AMP-activated protein kinase) in the control of muscle glycogen turnover and related meat traits (pH, water retention, color), and the involvement of BCMO1 (β, β-carotene-15, 15'-monooxygenase) in controlling levels of carotenoid pigments and yellow color. Our results emphasize in both cases the possibility of modulating quality traits through nutrition, with effects that depend on the genetic characteristics of animals. Our work has also improved the understanding of the regulation of studied biomarkers by genetics and nutrients. This should contribute to the development of new production strategies to optimize the quality of broilers in response to expectations of poultry producers and consumers