Dietary Non-phytate Phosphorus Research Articles

Dietary non-phytate phosphorus requirements for optimal productive and reproductive performance, and egg and tibial quality in egg-type duck breeders

Optimal dietary non-phytate phosphorus (NPP) is essential in poultry to maximise productive and reproductive performance, along with indices of egg and bone quality. This study aimed to establish the NPP requirements of egg-type duck breeders aged from 54 to 80 weeks on the following traits: egg production, egg incubation, egg quality, tibial characteristics, reproductive organ, plasma indices, and the expression of genes related to phosphorus absorption. Longyan duck breeders aged 54 weeks (n = 300) were randomly allotted to five treatments, each containing six replicates of 10 individually caged birds. Birds were fed corn-soybean meal-based diets containing 0.18, 0.25, 0.32, 0.38, and 0.45% NPP/kg for 27 weeks. The tested dietary NPP levels did not affect egg production or egg quality indices. The hatchling weight of ducklings increased (quadratic, P < 0.01) as dietary NPP level increased, and the highest value occurred with 0.25% NPP. The number of large yellow follicles (LYF), and the relative weights of LYF and ovary showed linear and quadratic responses to dietary NPP levels; the lowest number and relative weight of LYF occurred with 0.38% NPP, and the lowest ovarian weight was obtained with 0.25% NPP. There were no differences in tibial length, breaking strength, and mineral density in response to dietary NPP levels. In contrast, tibial content of Ca increased (linear, P < 0.01) with dietary NPP levels increasing from 0.18 to 0.45%, and the tibial content of P increased at 0.32% NPP and the higher dietary NPP levels. Plasma concentration of P showed a quadratic (P < 0.05) response to the dietary NPP levels, where the highest value was seen at 0.38% NPP. In conclusion, dietary NPP levels from 0.18 to 0.45% had no effects on egg production, and egg and tibial quality of duck breeders. The duck breeders fed a diet with 0.25% NPP showed the highest hatchling weight of their offspring, while those fed 0.38% NPP had the lowest number and relative weight of LYF. These results indicated that the diet with 0.25% NPP can be used in egg-type duck breeders to improve the hatchling weight of their offspring, without adverse effects on their productivity. The regression model indicated that the maximal hatchling weight of ducklings was obtained from duck breeders fed the diet with 0.30% NPP.

Effect of replacing dicalcium phosphate with mono-dicalcium phosphate to supplement phosphorus on laying performance, phosphorus-calcium metabolism and bone metabolism of aged laying hens.

The objective of this study was to evaluate the effect of replacing dicalcium phosphate (DCP) with mono-dicalcium phosphate (MDCP) to formulate low-phosphorus (P) diets on laying performance, egg quality, phosphorus-calcium metabolism, and bone metabolism of 69-78-week-old aged laying hens. Hy-Line Brown laying hens (n = 1,350, 69 weeks old) were randomly assigned to six treatments, each with five replicates of 45 hens. A corn-soybean meal-based diet was formulated to contain 0.12% non-phytate phosphorus (NPP), 3.81% calcium (Ca), and 1,470 FTU/kg phytase. The control group (CON) was supplemented with DCP inorganic phosphorus (Pi) at the NPP level of 0.20% (dietary NPP levels of 0.32%). Test groups (T1-T5) were supplemented with MDCP Pi at NPP levels of 0.07%, 0.11%, 0.15%, 0.18, and 0.20% (dietary NPP levels of 0.19, 0.23, 0.27, 0.30, and 0.32%, respectively). Calcium carbonate levels were adjusted to ensure all experimental diets contained the same Ca levels (3.81%). The feeding trial lasted 10 weeks, with hens increasing in age from 69 to 78 weeks. When supplemented with 1,470 FTU/kg phytase, extra DCP Pi or MDCP Pi did not affect (p > 0.05) laying performance (day laying rate, average egg weight, feed intake, feed-to-egg mass ratio, broken egg rate), egg quality (eggshell strength, albumen height, haugh units), or serum P, Ca, copper (Cu), iron (Fe), zinc (Zn), and manganese (Mn) levels. However, when laying hens were fed MDCP Pi (NPP levels of 0.07 to 0.20%), yolk color improved (p = 0.0148). The tibia breaking strength was significantly higher (p < 0.05) in the 0.18 and 0.20% NPP MDCP Pi groups than in the 0.20% NPP DCP Pi group. The breaking strength, Ca content, and P content of tibia in 0.11% and 0.15% NPP MDCP Pi hens were not significantly (p > 0.05) different from those in 0.20% NPP DCP Pi hens. Hens fed 0.07% NPP MDCP Pi had higher (p < 0.01) serum levels of osteoprotegerin (OPG), type-I collagen c-telopeptide (CTX-I), and tartrate-resistant acid phosphatase 5b (TRACP-5b) than those in all other groups. Serum levels of TRACP-5b and CTX-I in the 0.11% and 0.15% NPP MDCP Pi group were significantly lower than those in 0.18 and 0.20% NPP MDCP Pi groups and the 0.20% NPP DCP Pi group (p < 0.0001). Hens fed 0.07% and 0.11% NPP MDCP Pi had higher (p < 0.05) serum levels of parathyroid hormone (PTH) than those in all other groups. No differences were detected in serum calcitonin (CT), 1,25-dihydroxy-vitamin D3 (1,25-(OH)2D3), bone alkaline phosphatase (BAP), osteocalcin(OCN), and osteopontin (OPN) among all groups (p > 0.05). The expression of P transporters type IIa Na/Pi cotransporter (NaPi-IIa) in 0.11% and 0.15% NPP MDCP Pi hens were higher than those in 0.20% NPP MDCP Pi group and 0.20% NPP DCP Pi group (p < 0.05). The results indicated that both renal P reabsorption and bone resorption were involved in adapting to a low-P diet. In summary, when MDCP was used instead of DCP to supplement P, NPP levels could be reduced to 0.11% (dietary NPP level of 0.23%) without negative effects on laying performance and skeletal health of aged hens. In addition, MDCP was more beneficial than DCP for tibia quality. The results of the current study would provide references for the application of MDCP in low-P diets of aged laying hens.

Effects of Low-Phosphorus Diets Supplemented with Phytase on the Production Performance, Phosphorus-Calcium Metabolism, and Bone Metabolism of Aged Hy-Line Brown Laying Hens

This study was conducted to evaluate the effects of phytase supplementation in low-phosphorus diets on the production performance, phosphorus-calcium metabolism, and bone metabolism in laying hens from 69 to 78 weeks of age. Hy-Line Brown laying hens (n = 1350) were assigned randomly to six treatments with five replicates of 45 birds. A corn-soybean meal-based diet with no inorganic phosphates was formulated to contain 0.12% non-phytate phosphorus (NPP) and 1470 FTU/kg phytase (Released phytate phosphorus content ≥ 0.1%). Inorganic phosphorus (dicalcium phosphate) was supplemented into the basal diet to construct five test diets (level of NPP supplementation = 0.10%, 0.15%, 0.20%, 0.25%, and 0.30%). The level of calcium carbonate was adjusted to ensure that all six experimental diets contained the same calcium percentage (3.81%). The feeding trial lasted 10 weeks (hens from 69 to 78 weeks of age). Upon supplementation with phytase (1470 FTU/kg), supplemental inorganic phosphates (dicalcium phosphate) had no significant effects (p > 0.05) on the production performance or egg quality. Significant differences in serum levels of calcium, phosphorus, copper, iron, zinc, or manganese were not detected across treatments (p > 0.05). Hens fed NPP (0.15%, 0.20%, 0.25%, and 0.30%) had higher levels (p < 0.0001) of tibial ash, calcium, and phosphorus than those not fed inorganic phosphates. The tibial breaking strength of the group without inorganic phosphates was significantly lower than that of the other groups (p < 0.01). Dietary supplementation with inorganic phosphates had no effect (p > 0.05) on serum levels of calcitonin (CT) and 1,25-dihydroxy-vitamin D3 (1,25-(OH)2D3). Hens that did not receive supplementation with inorganic phosphates had higher serum levels of parathyroid hormone (PTH), osteoprotegerin (OPG), type-I collagen c-telopeptide (CTX-I), and tartrate-resistant acid phosphatase 5b (TRACP-5b) compared with those in the other groups (p < 0.01). Serum levels of CTX-I and TRACP-5b were significantly lower in the NPP-supplementation groups of 0.25% and 0.30% than in the 0.10% NPP-supplementation group (p < 0.01). Dietary supplementation with inorganic phosphates had no effect (p > 0.05) on serum levels of bone-alkaline phosphatase (BAP), osteocalcin (OCN), or osteopontin (OPN). Hens not fed inorganic phosphate had the highest renal expression of phosphorus transporter type IIa Na/Pi cotransporter (NaPi-Ⅱa). Renal expression of NaPi-Ⅱa was increased significantly in NPP-supplementation groups of 0.10-0.20% compared with that in NPP-supplementation groups of 0.25% and 0.30% (p < 0.0001). The results indicated that a reduction in NPP supplementation to 0.15% (dietary NPP level = 0.27%) with phytase inclusion did not have an adverse effect on the production performance or bone health of laying hens from 69 to 78 weeks of age, which might be attributed to renal phosphorus reabsorption and bone resorption. These findings could support the application of low-phosphorus diets in the poultry industry.

Dietary calcium and non-phytate phosphorus levels affect the performance, serum biochemical indices, and lipid metabolism in growing pullets

This experiment aimed to study the effects of dietary calcium (Ca) and non-phytate phosphorus (NPP) levels on performance, serum biochemical indices, and lipid metabolism in Beijing You Chicken (BYC), a local chicken. A 3×3 factorial design was adopted, dietary Ca levels were 0.66, 0.71, and 0.76%, NPP levels were 0.25, 0.30, and 0.35%. A total of 648 ten-wk-old BYC growing pullets were randomly divided into 9 groups with 6 replicates per group, and 12 birds per replicate. Growth performance, serum biochemical indices, and lipid metabolism indicators from 10 to 16 wk were measured. The results showed as follows: 1) Dietary Ca and NPP alone did not affect growth performance, but the interaction of dietary Ca and NPP affected average feed intake (AFI) of growing pullets (P < 0.05). The AFI was the lowest for the group with 0.71% Ca and 0.25% NPP (3,550.0 g, P=0.036). 2) Dietary Ca level significantly affected serum P content (P < 0.05); dietary NPP had an influence trend on serum Ca content (P=0.054). Dietary NPP levels and the interaction of Ca and NPP significantly affected alkaline phosphatase (AKP) activity. 3) Dietary Ca levels significantly affected TC content and HDL-C content (P < 0.05). Dietary NPP level significantly affected TG content (P < 0.05), the TG content in 0.25% and 0.30% NPP groups was significantly lower than that in 0.35% NPP group (P < 0.05). The interaction of dietary Ca and NPP significantly affected TG, TC and HDL-C contents (P < 0.05). TG, TC, and LDL-C levels were lower and HDL-C levels were the highest in the group with 0.66% Ca and 0.25% NPP. In summary, appropriate dietary Ca level can regulate serum TG, TC, and HDL-C content. Dietary Ca and NPP levels can be adjusted in pullet phase to avoid excessive obesity during the egg-laying period. This study recommended that dietary 0.66% Ca and 0.25% NPP benefit for the lipid metabolism of BYC growing pullets without affecting the performance.

Effects of graded levels of phytase supplementation on growth performance, plasma myo-inositol, tibia mineralization and nutrient digestibility of meat ducks fed phosphorus-deficient diets

Two experiments were conducted to explore the effect of reduction in dietary non-phytate phosphorus (nPP) and supplementation of an exogenous phytase on growth performance, plasma myo-inositol, tibia mineralization and nutrient digestibility of meat ducks. Exp. 1 used 450 one-day-old male Cherry Valley ducks over a 42-d period to evaluate growth performance and plasma myo-inositol. The treatments (6 replicates with 15 ducks per pen) included a positive control diet (PC, 4.0 and 9.0 or 3.5 and 8.0 g/kg of nPP and Ca in starter (d 0–21) and grower (d 21–42) period, respectively), a negative control diet (NC, 1.7 g/kg nPP and 1.9 g/kg Ca less from the PC), and the NC diet plus phytase at 1000, 2000 or 3000 FYT/kg feed. Exp. 2 used 600, seven-day-old, male Cherry Valley ducks in a 14-d trial to evaluate growth performance, tibia mineralization and nutrient digestibility. Dietary treatments (10 replicate cages with 10 ducks per cage) included a PC diet (4.0 and 9.0 g/kg of nPP and Ca, respectively), a NC diet (1.5 and 6.5 g/kg of nPP and Ca, respectively), and the NC diet plus phytase at 500, 1000, 2000 or 3000 FYT/kg feed. In Exp. 1, ducks fed the NC diet had lower (P < 0.05) weight gain (d 0–21 and 0–42), feed intake (d 0–21, 21–42 and 0–42) and body weight at d 21 and 42 compared to those fed the PC diet. There was no effect of diet (P > 0.05) on FCR or plasma myo-inositol. Phytase supplementation linearly increased (P < 0.05) weight gain, feed intake, and body weight; all parameters were equivalent to the PC at 2000 or 3000 FYT/kg. In Exp. 2, ducks fed the NC diet had lower (P < 0.05) weight gain, feed intake, body weight, tibia ash weight and percentage, and P digestibility and higher (P < 0.05) FCR and Ca digestibility compared to those fed the PC diet. Phytase supplementation improved growth measurements (linear and quadratic, P < 0.05), tibia ash weight and percentage (linear, P < 0.05) and P digestibility (linear, P < 0.05). Growth measurements and P digestibility were comparable to the PC level with supplemented phytase ranging from 1000 to 2000 FYT/kg, however, tibia ash weight and percent were below the PC, regardless of the dose of phytase. In conclusion, feeding graded concentrations of phytase improved growth performance, tibia mineralization, and P digestibility in ducks. Phytase supplementation at 2000 FYT/kg could fully restore the gain and P digestibility of ducks fed nPP deficient diets to that of a nutrient adequate PC. However, in extremely nPP deficient diets, tibia ash weight and percentage require a higher supplementation of phytase, which was beyond 3000 FYT/kg.

Recommended levels of calcium and non-phytate phosphorus for yellow-feathered broilers (finisher phase).

This study examined the effects of dietary calcium (Ca) and non-phytate phosphorus (NPP) on performance, tibial characteristics, meat quality and plasma biochemical variables in yellow-feathered broilers during 85 to 105 d of age. A total of 720 heads of 85-d broilers were allocated into 9 groups and provided with three levels of Ca (0.65%, 0.75%, 0.85%), and NPP (0.25%, 0.30%, 0.35%) in diets for 21 d. The final body weight (FW), average daily gain (ADG), average daily feed intake (ADFI), and feed to gain ratio (F:G) were affected (p<0.05) by dietary Ca. From the quadratic regressions, the optimal level of Ca in diet were 0.71% for FW and ADG, and 0.67% for ADFI. Dietary Ca and NPP both significantly affected tibial breaking strength and density. From the quadratic regressions, the optimal level of Ca and NPP in diet were 0.81% and 0.37% for tibial density. The shear force of breast muscle of broilers given 0.75% or 0.85% Ca were lower than that in birds with 0.65% Ca and drip loss of birds given 0.65% or 0.75% Ca was lower than that in birds with 0.85% Ca (p<0.05). The drip loss of birds given 0.25% NPP was lowest among all NPP treatments (p<0.05). Calcium affected (p<0.05) the plasmal contents of phosphorus, osteocalcin (OC), parathyroid hormone (PTH) and calcitonin and the contents of OC and PTH were also influenced by dietary NPP. Dietary Ca and NPP level affected tibial characteristics, meat quality and biochemical variables in plasma of finisher-phase yellow-feathered broilers (85 to 105 d) and Ca also affected growth performance. Dietary 0.71% Ca and 0.30% NPP were enough for growth performance, while considering the growth performance, tibial characteristics, meat quality and biochemical variables together, 0.75% Ca and 0.37% NPP were recommended.

Growth Performance, Bone Development and Phosphorus Metabolism in Chicks Fed Diets Supplemented with Phytase Are Associated with Alterations in Gut Microbiota.

Simple SummaryPhosphorus is a crucial component of nucleic acids, phospholipids, several coenzymes and bone, and plays numerous roles in nutrient metabolism in animals. We investigated the growth performance, bone development, phosphorus metabolism and gut microbiota changes elicited by different phosphorus levels with/without phytase in chicks during the brooding period. Low-phosphorus diets inhibited growth performance and bone development, decreased utilization of phosphorus and altered gut microbial structure and function in the brooding stage of chicks. Inclusion of phytase improved growth performance and bone development and decreased phosphorus emission. The potential mechanisms may be associated with gut microbiota reprogramming.Phosphorus pollution caused by animal husbandry is becoming increasingly problematic, especially where decreasing and non-renewable phosphorus resources are concerned. We investigated the growth performance, bone development, phosphorus metabolism and gut microbiota changes elicited by different phosphorus levels with/without phytase in chicks during the brooding period (1–42 d). Five-hundred-and-forty (540) egg-laying chickens were assigned to six groups (0.13% NPP, 0.29% NPP, 0.45% NPP, 0.13% NPP + P, 0.29% NPP + P and 0.45% NPP + P) according to a factorial design with three non-phytate phosphorus (NPP) levels (0.13, 0.29 and 0.45%) and two phytase (P) dosages (0 and 200 FTU/kg). Chicks fed with the diet with 0.13% NPP had the lowest body weight, average daily gain, shank length, average daily feed intake and highest ratio of feed to gain, while phytase supplementation was able to mitigate the adverse effects of low-phosphorus diets on growth performance. Moreover, phosphorus metabolism was affected by different dietary NPP and phytase levels. Thus, 0.13% NPP significantly reduced serum phosphorus, while phytase supplementation significantly increased serum phosphorus. Notably, phosphorus utilization in the 0.13% NPP group was significantly decreased and the phosphorus excretion ratio was increased. Phytase supplementation significantly improved phosphorus utilization by 43.79% and decreased phosphorus emission in the 0.13% NPP group but not in the 0.29% NPP or the 0.45% NPP group. Remarkably, the alpha diversity of gut microbiota was significantly decreased in the low-phosphorus group, while phytase supplementation increased alpha diversity and improved gut microbial community and function. The LEfSe analysis revealed that several differential genera (e.g., Bacteroides, norank_f__Clostridiales_vadinBB60_group and Eggerthella) were enriched in the different dietary NPP and phytase levels. Furthermore, correlations between differential genera and several crucial phenotypes suggested that the enrichment of beneficial bacteria with different levels of phosphorus and phytase promoted phosphorus utilization in the foregut and hindgut. In summary, low-phosphorus diets inhibited growth performance and bone development, decreased utilization of phosphorus and altered gut microbial structure and function in the brooding stage of chicks. Finally, phytase supplementation improves growth performance and bone development and decreases phosphorus emission, and the potential mechanisms may be associated with the reprogramming of gut microbiota.

Requirement of Non-Phytate Phosphorus in 1- to 28-Day-Old Geese Based on Growth Performance, Serum Variables, and Bone Characteristics

The standard of dietary non-phytate phosphorus (NPP) requirement is important for geese production. However, limited reports remain an obstacle to the NPP requirement of geese. We aimed to evaluate the NPP requirement in geese based on the effects of NPP levels on growth performance, serum variables, and bone characteristics in 1–28-day-old geese. One-day-old male Jiangnan White Geese (n = 360) were randomly divided into five groups. Five corn-soybean diets were used in these groups, with NPP levels at 0.18%, 0.28%, 0.39%, 0.47%, 0.59% in the feed, respectively. The average body weight, serum phosphorus (P) content, tibia strength, tibia P content, and femoral skim weight were significantly reduced, by 0.18%, compared with 0.28–0.59%. These variables had significant linear fit (p &lt; 0.001) between the levels of 0.18% and 0.58%. The estimated requirement of NPP for goslings is between 0.28% and 0.35%, based on the broken-line model, using the above indicators. In conclusion, the dietary NPP requirement for 1–28-day-old geese should be no less than 0.35% to ensure normal growth performance and bone development, based on body weight gain, serum P content, and skeletal variables.

Regulation of bone phosphorus retention and bone development possibly by BMP and MAPK signaling pathways in broilers

The bone morphogenetic protein (BMP) and mitogen-activated protein kinase (MAPK) signaling pathways play an important role in regulation of bone formation and development, however, it remains unclear that the effect of dietary different levels of non-phytate phosphorus (NPP) on these signaling pathways and their correlations with bone phosphorus (P) retention and bone development in broilers. Therefore, this experiment was conducted to investigate the effect of dietary P supplementation on BMP and MAPK signaling pathways and their correlations with bone P retention and bone development in broilers. A total of 800 one-day-old Arbor Acres male broilers were randomly allotted to 1 of 5 treatments with 8 replicates in a completely randomized design. The 5 treatments of dietary NPP levels were 0.15, 0.25, 0.35, 0.45 and 0.55% or 0.15, 0.22, 0.29, 0.36 and 0.43% for broilers from 1 to 21 days of age or 22 to 42 days of age, respectively. The results showed that extracellular signal-regulated kinase 1 (ERK1) mRNA expression in the tibia of broilers on days 14 and 28, phosphorylated-ERK1 (p-ERK1) on day 14, and BMP2 protein expression on days 28 and 42 decreased linearly (P<0.04), while c-Jun N-terminal kinase 1 (JNK1) mRNA expression on day 42 increased linearly (P<0.02) with the increase of dietary NPP level. At 14 days of age, total P accumulation in tibia ash (TPTA), bone mineral concentration (BMC), bone mineral density (BMD), bone breaking strength (BBS) and tibia ash were negatively correlated (r=–0.726 to –0.359, P<0.05) with ERK1 and JNK1 mRNA as well as p-ERK1; tibia alkaline phosphatase (ALP) and bone gal protein (BGP) were positively correlated (r=0.405 to 0.665, P<0.01) with ERK1 mRNA and p-ERK1. At 28 days of age, TPTA, BMC, BMD, BBS and tibia ash were negatively correlated (r=–0.518 to –0.370, P<0.05) with ERK1 mRNA and BMP2 protein, while tibia ALP was positively correlated (r=0.382 to 0.648, P<0.05) with them. The results indicated that TPTA, BMC, BMD, BBS or tibia ash had negative correlations, while tibia ALP and BGP had positive correlations with ERK1 and JNK1 mRNAs, BMP2 protein and p-ERK1, suggesting that bone P retention and bone development might be regulated by BMP and MAPK signaling pathways in broiler chickens.

Effects and interaction of dietary calcium and non-phytate phosphorus for slow-growing yellow-feathered broilers during the starter phase

Calcium (Ca) and non-phytate phosphorus (NPP) are fundamental minerals for bone formation and growth, and optimizing their level is required in broiler production. This experiment was conducted to investigate the effect and interaction of dietary Ca and NPP on growth performance, tibial characteristics and biochemical variables for slow-growing yellow-feathered broilers during 1–28 d (the starter phase). Seven hundred and twenty hatchling female broilers were randomly divided into nine groups, which received three levels of Ca (0.80%, 0.90%, 1.00%) each with three levels of NPP (0.40%, 0.45%, 0.50%). The results showed: (1) Dietary Ca level influenced (P < 0.05) the feed to gain ratio (F:G) and average daily feed intake (ADFI). Compared with broilers provided 1.00% Ca, ADFI of birds provided with 0.80% or 0.90% Ca and F:G of those with 0.90% Ca were decreased (P < 0.05). Dietary NPP level did not affect (P > 0.05) growth performance of broilers. (2) Dietary Ca affected (P < 0.05) tibial length. Compared with birds provided with 0.80% Ca, the length of tibia was decreased (P < 0.05) in birds received 1.00% Ca. Interactions between dietary Ca and NPP were observed (P < 0.05) on ash content, breaking strength and bone density of tibia. These three characteristics were better when birds received 0.90% Ca and 0.40% NPP or 1.00% Ca and 0.45% NPP. (3) Dietary Ca significantly affected (P < 0.05) the activity of alkaline phosphatase (ALP) in serum with decreased activity in birds fed 0.80% or 0.90% Ca. The dietary NPP influenced (P < 0.05) the contents of Ca in serum. Serum Ca was increased when birds were provided 0.40% NPP compared with other levels (P < 0.05). Again, there was interaction between Ca and NPP in diet on the contents of phosphorus (P) in serum (P < 0.05). In conclusion, interactions occurred between dietary Ca and NPP level on tibial breaking strength, density, ash content, and the content of P in the serum of young yellow-feathered broilers. Furthermore, dietary Ca affected ADFI, F:G and serum ALP activity, and dietary NPP also affected the P content in serum. Considering all indicators, 0.90% Ca and 0.40% NPP are optimal for slow-growing yellow-feathered broilers during 1–28 d of age.

Effects and interaction of dietary calcium and nonphytate phosphorus for slow-growing yellow-feathered broilers between 56 and 84 d of age

This experiment investigated the effect and interaction of dietary calcium (Ca) and nonphytate phosphorus (NPP) on growth performance, tibial characteristics, carcass traits, and meat quality for slow-growing yellow-feathered broilers during 56 to 84 d of age. A 3 × 3 factorial arrangement was used, and 720 56-day-old broilers were randomly divided into 9 groups and fed with diets containing different levels of Ca (0.70, 0.80, 0.90%) and NPP (0.30, 0.35, 0.40%) for 28 d. The dietary Ca level affected the ADFI of yellow-feathered broilers (P < 0.05), and the ADFI of birds fed with 0.90% Ca was increased (P < 0.05) compared with that of birds fed with 0.70% Ca. Birds received 0.35 or 0.40% NPP had higher final BW, ADG, and ADFI than those fed with 0.30% NPP (P < 0.05). The tibial diameter of birds fed with 0.80% Ca was increased compared with that of other groups (P < 0.05). The dietary NPP level did not affect tibial characteristics (P > 0.05). The dietary Ca level did not affect carcass traits (P > 0.05). When broilers were fed with 0.30% P, the semieviscerated percentage was increased compared with birds fed with 0.40% NPP (P < 0.05). The dietary Ca level had significant effects on the L∗ value and shear force of the breast muscle, and the dietary NPP level affected the L∗ value and drip loss of the breast muscle (P < 0.05). Furthermore, the effect of interaction between the level of Ca and NPP was observed on the L∗ and a∗ value (P < 0.05). In conclusion, dietary Ca had influence on performance, tibial characteristics, and meat quality of yellow-feathered broilers, and dietary NPP affected performance, tibial characteristics, and carcass traits. Furthermore, the effect of interaction between the dietary Ca and NPP level was observed on carcass traits and meat quality. Considering all aforementioned indicators, 0.80% Ca and 0.35% NPP were recommended for slow-growing yellow-feathered broilers aged 57 to 84 d of age.

Evaluation of a novel corn-expressed phytase on growth performance and bone mineralization in broilers fed different levels of dietary nonphytate phosphorus

Summary An experiment was conducted to evaluate the effects of dietary nonphytate phosphorus level and a novel corn-expressed phytase (GraINzyme, Agrivida Inc., Woburn, MA) supplementation on broiler growth performance and bone mineralization. Broilers were fed graded levels of nonphytate phosphorus from 0.20 to 0.44% increased by 0.06% and 4 levels of corn-expressed phytase (500; 1,500; 3,000; and 4,500 FTU/kg). Dicalcium phosphate was used as the reference for inorganic phosphorous. Increasing dietary nonphytate phosphorus level or supplementation of phytase linearly (P

Response of modern broiler chickens to dietary calcium and phosphorus levels below recommendations

This study was carried out to investigate the effects of reduced dietary calcium (Ca) and non-phytate-phosphorus (NPP) levels on performance, carcase yield and bone mineralisation of modern broilers. 11,200 one-day-old chicks (Ross-308) were divided into 7 treatments and 8 replicates with standard recommended level and six different levels of Ca and NPP reduction with completely randomised block design. Treatments were divided into following diets; T1: ross recommended control, T2: 94%, 95% and 91% as percentage of T1, T3: 94%, 95% and 83% as percentage of T1, T4: 94%, 91% and 83% as percentage of T1, T5: 94%, 91% and 77% as percentage of T1, T6: 94%, 86% and 83% as percentage of T1 and T7: 94%, 86% and 77% as percentage of T1 for starter, grower and finisher periods, respectively. Results showed that, the Ca and NPP reduction (T2–T7) through starter period did not significantly (p>.05) affect performance but when considered whole period, quadratically (p<.05) improved body weight gain (BWG), feed conversion ratio (FCR) and European Production Efficiency (EPEF). In line with, Ca and NPP intakes were decrease linearly and quadratically with Ca and NPP reducing in diet and higher intakes at T1 resulted in impaired BWG and FCR. On the other hand, carcase parameters and tibia mineralisation were not significantly affected by the reductions. In conclusion, Ca and NPP requirements of Ross 308 broilers seem to be lower than the Aviagen 2014 and 2019 recommendations and reducing almost 20% Ca and NPP intake of broilers is possible, especially after starter period, to maintain performance without any negative effect on bone development. Highlights Excessive dietary Ca and P feeding have potential deleterious effects on broilers. Dietary Ca and NPP reduction improved growth performance, without impairment bone characteristics. Especially after starter period, Ca and NPP reduction, by keeping the dietary levels as 0.90:0.45, 0.75;0.38 and 0.60;0.30% for starter, grower and finisher phase respectively, seems enough for Ross-308.

Effect of high-dose phytase and low calcium concentration on performance of broiler chicken given diet severely limited in nonphytate phosphorus

The effect of phytase and calcium ( Ca ) was investigated on performance of broiler chickens given diets severely limited in nonphytate phosphorus ( NPP ). A total of 550 ten-day-old broiler chickens were allocated to 10 diets from 11 to 40 d of age. There were a positive control (with adequate Ca and NPP concentration) and 9 diets (with 1.4 g NPP/kg) consisting of Ca (5.6, 4.2, and 2.8 g/kg) and phytase (0, 1,500, and 3,000 FTU/kg) in a 3 × 3 factorial arrangement of treatments with 5 pens per treatment. Increasing phytase dose linearly increased BW ( P < 0.001) and tibia ash ( P < 0.001) and reduced feed-to-gain ratio ( F:G , P < 0.001) and mortality ( P < 0.05). Increasing phytase dose quadratically affected tarsometatarsus strength ( P < 0.001) and tibia ash percentage ( P < 0.05). Decreasing Ca concentration linearly increased BW ( P < 0.001) and reduced F:G ( P < 0.001), mortality ( P < 0.01), and tibia ash ( P < 0.05). In terms of BW ( P < 0.05), F:G ( P < 0.01), mortality ( P < 0.05), tibia ash ( P < 0.05), and tarsometatarsus strength ( P < 0.01), response to phytase addition was greater for high Ca concentrations, resulting in a Ca × phytase interaction. Generally, increasing phytase dose or decreasing Ca concentration in severely low NPP diet has beneficial effect on BW, F:G, and mortality of broiler chicken. If performed in combination, performance results improve even more. Nonetheless, when phytase is supplemented in the diet, decreasing Ca concentration does not allow maximum bone strength and ash.

Inorganic feed phosphate type determines mineral digestibility, broiler performance, and bone mineralization

Summary An experiment was conducted to evaluate early broiler performance, tibia mineralization, and mineral digestibility of broilers fed with diets that differed in inorganic feed phosphates (IFP) but were formulated to be similar in dietary nonphytate phosphorus (nPP) content and calcium-to-phosphorus ratio (Ca:P), total mineral content, or calculated prececal digestible phosphorus (CPDP). Dicalcium phosphate (DCP), monodicalcium phosphate (MDP), monocalcium phosphate (MCP), and defluorinated phosphate were used in formulations with similar nPP content and Ca:P. In addition to these 4 treatments, a mixture of MCP, monosodium phosphate, and DCP was used to assimilate total mineral content of MDP (DMM). Moreover, a mixture of MCP and silicon dioxide was used to produce a similar CPDP content as the DCP diet (MCP + SiO2). The MCP + SiO2 diet had the lowest IFP inclusion. The study used a randomized complete block design with 10 replications of 10 male broilers fed with each of the 6 dietary treatments for 21 D. Linear contrasts were used to compare treatments of interest. Birds fed with MCP demonstrated increased live weight gain, tibia ash (mg/chick), and mineral digestibility compared with birds fed with DCP when diets were formulated to similar nPP content and Ca:P (P

Phosphorus Restriction Changes the Expression of Fibroblast Growth Factor 23 and Its Receptors in Laying Hens

Dietary phosphorus oversupply wastes non-renewable natural resources and raises environmental concerns in animal agriculture. We hypothesized that laying hens do not need large safety margins for dietary phosphorus because of the existence of fibroblast growth factor 23 (FGF23). In experiment 1, a total of 504 Hy-Line Brown laying hens (40-week-old) were randomly assigned to seven diets (for each diet, six replicates of 12 hens), containing 0.12, 0.17, 0.22, 0.27, 0.32, 0.37, and 0.42% non-phytate phosphorus, respectively, for 15 weeks. In experiment 2, a total of 14 Hy-Line Brown laying hens (40-week-old) were randomly assigned to two diets: (1) phosphorus restricted (n = 7) diet containing 0.14% non-phytate phosphorus, and (2) regular phosphorus (n = 7) diet containing 0.32% non-phytate phosphorus, for 21 days. Laying performance and egg quality were investigated in experiments 1 and 2. Phosphorus excretion and physiological changes were determined in experiment 2. It was found that dietary non-phytate phosphorus levels had no effects (P > 0.05) on laying performance and egg quality in either experiment. In experiment 2, laying hens fed 0.14% non-phytate phosphorus had decreased phosphorus excretion (by 52.6%, P < 0.001) when compared to those fed 0.32% non-phytate phosphorus. In response to the 0.14% non-phytate phosphorus diet, laying hens in experiment 2 exhibited: (1) suppressed calvaria mRNA expressions of FGF23 (by 57.8%, P < 0.001) and fibroblast growth factor receptor 1 (FGFR1, by 52.8%, P = 0.012), (2) decreased serum levels of FGF23 (by 41.7%, P = 0.011) and phosphorus (by 40.3%, P < 0.001), (3) decreased kidney mRNA expressions of FGFR1 (by 66.0%, P = 0.040) and FGFR4 (by 63.3%, P = 0.012) and decreased kidney protein expression of type 2a sodium-phosphorus co-transporter (NPt2a, by 51%, P = 0.025), (4) increased duodenum protein expression of NPt2b (by 45%, P = 0.032), and (5) increased excretion of calcium (by 22.9%, P ≤ 0.024). Collectively, decreasing dietary non-phytate phosphorus by up to 0.12% had no negative effects on egg-production performance but significantly decreased phosphorus excretion in laying hens. The laying hens adjusted to low-phosphorus diets by increasing intestinal NPt2b protein production, which was associated with decreased serum FGF23 concentration. Decreasing dietary non-phytate phosphorus is suggested to laying-hen nutritionists.

The effects of coarse and wet feeding on performance parameters, gastrointestinal tract and tibia traits, and digesta phytase activity in egg-type pullets, either fed a low or moderate phosphorus diet

In a 2 × 2 × 2 factorial design, the effects of dietary non-phytate phosphorus (NPP) levels, 0.17% (low) and 0.33% (moderate), diet moisture (dry and wet), and diet particle size (coarse and fine), were studied on egg production, characteristics of gastrointestinal tract (GIT) and tibia, digesta pH, and phytase activity in layer pullets (16 to 28 wk of age). The low NPP diet increased average daily water intake (ADWI) to ADFI ratio (4.2%) from 16 to 17 wk, but decreased this ratio (2.8%) from 23 to 27 wk. It decreased ADFI (1.5%) and egg mass production (3.8%) from 19 to 22 wk. It decreased egg weight (0.29g) and ADWI (2.1%) from 23 to 27 wk. At 22 wk, the GIT relative empty organ weights were (g/kg BW) higher for proventriculus + gizzard (0.96), duodeneum (0.94), and jejunum + ileum (1.95) with the low vs. moderate NPP diet. The low NPP diet decreased digesta phytase activity in crop and proventriculus+gizzard at 28 wk. The wet diet increased ADFI, ADWI, and ADWI/ADFI ratio from 16 to 27 wk, egg mass production (3.0%) from 19 to 22 wk, and egg weight (0.45g) from 23 to 27 wk. The wet diet also increased digesta phytase activity in proventriculus+gizzard. The coarse diet decreased ADFI from 19 to 22 wk (1.7%) and 23 to 27 wk (1.2%). The coarse diet caused reduced egg mass production (2.6%) from 23 to 27 wk. Egg shell breaking strength was increased on the coarse diet (0.9 Newton). The coarse diet increased ADWI/ADFI ratio from 16 to 27 wk, and increased relative gizzard weight by 1.95 and 0.81g/kg BW at 22 and 28 wk, respectively. The coarse diet increased jejunal/ileal pH with 0.16 units at 28 wk. None of the tested parameters affected tibia characteristics. It was concluded that a low NPP diet did not clearly affect the studied parameters. The wet diet increased ADFI, ADWI, and egg production. The coarse diet increased ADWI, egg shell breaking strength, relative gizzard weight, and reduced ADFI and egg production.

Restriction of dietary non-phytate phosphorus on growth performance and expression of intestinal phosphate cotransporter genes in broilers

Effects of dietary non-phytate phosphorus (nPP) restriction on growth and duodenal type IIb sodium-dependent phosphate cotransporter (NaPi-IIb) genes were observed. A total of 432 one-day old Cobb500 male broiler chickens in 36 cage pens were divided into 6 groups with each group containing 6 pens. Each group was treated with one of the diets containing 0.33, 0.37, 0.41, 0.45, 0.49, and 0.53% of nPP up to 14 D. During 15 to 31 D, birds were treated with one of the diets containing 0.23, 0.27, 0.31, 0.35, 0.39, and 0.43% of nPP. Level of Ca was kept the same across all treatments. Dietary nPP level influenced (P < 0.001) weight gain and feed intake in both growth phases, whereas effect on feed per gain ratio was seen only in the second phase. Toe ash, tibia ash, and tibia breaking strength responded to treatments (P < 0.01) at 14 D. Only tibia ash content was significantly improved (P < 0.001) at 31 D. Growth and bone parameters linearly improved with an increase in dietary nPP content (P < 0.05). Above dietary nPP 0.41% and 0.31% for first phase and second phase, respectively, no significant improvement was seen. Duodenal NaPi-IIb mRNA overexpressed with a decrease in dietary nPP in both phases (P < 0.05). Relative expression of NaPi-IIb in lowest nPP group were 2.2 folds higher in the first phase and 3.6 folds higher in the second phase compared to respective highest nPP groups of each phase. No significant change in NaPi-IIb expression was seen above 0.37% of dietary nPP for 14 D and 0.31% of dietary nPP for 31 D. Dietary requirements of nPP 0.41% for 0 to 14 D and 0.31% for 15 to 31 D were adequate for optimal growth and bone parameters. This study fills the gap in understanding of intestinal NaPi-IIb expression in response to dietary nPP restriction in broilers older than 21 D of age.

Dietary phosphorus deficiency impaired growth, intestinal digestion and absorption function of meat ducks.

ObjectiveAn experiment was conducted to investigate the effects of dietary non-phytate phosphorus (nPP) deficiency on intestinal pH value, digestive enzyme activity, morphology, nutrient utilization, and gene expression of NaPi-IIb in meat ducks from 1 to 21 d of age.MethodsA total of 525 one-d-old Cherry Valley ducklings were fed diets (with 7 pens of 15 ducklings, or 105 total ducklings, on each diet) with five levels of nPP (0.22%, 0.34%, 0.40%, 0.46%, or 0.58%) for 21 d in a completely randomized design. Five experimental diets contained a constant calcium (Ca) content of approximately 0.9%. Body weight (BW), body weight gain (BWG), feed intake (FI), and feed to gain ratio (F:G) were measured at 14 and 21 d of age. Ducks were sampled for duodenum and jejunum digestion and absorption function on 14 and 21 d. Nutrient utilization was assessed using 25- to 27-d-old ducks.ResultsThe results showed ducks fed 0.22% nPP had lower (p<0.05) growth performance and nutrient utilization and higher (p<0.05) serum Ca content and alkaline phosphatase (ALP) activity. When dietary nPP levels were increased, BW (d 14 and 21), BWG and FI (all intervals), and the serum phosphorus (P) content linearly and quadratically increased (p<0.05); and the jejunal pH value (d 14), duodenal muscle layer thickness (d 14), excreta dry matter, crude protein, energy, Ca and total P utilization linearly increased (p<0.05); however, the serum ALP activity, jejunal Na+-K+-ATPase activity, and duodenal NaPi-IIb mRNA level (d 21) linearly decreased (p<0.05).ConclusionThe results indicated that ducks aged from 1 to 21 d fed diets with 0.22% nPP had poor growth performance related to poor intestinal digestion and absorption ability; but when fed diets with 0.40%, 0.46%, and 0.58% nPP, ducks presented a better growth performance, intestinal digestion and absorption function.

Effect of reduced dietary non-phytate phosphorus concentration, with or without calcium reduction, in diets supplemented with phytase for weaned piglets from 28 to 63 days of age

The aim of this study was to investigate the impact of reduced dietary non-phytate phosphorus (nPP) or nPP and calcium (Ca) concentrations in diets supplemented with phytase on performance, bone mineralisation and serum parameters of weaned piglets from 28 to 63 days of age. A total of 168 barrows and gilts, weaned at 28 days of age, with an average initial bodyweight of 8.11 ± 0.61 kg were randomly allocated in a completely randomised block design. Treatments consisted of a positive control and an additional six treatments, in a 3 × 2 factorial arrangement, totalling seven treatments (Trt). The positive control (PC) diet was formulated to meet or exceed the nutrient requirements of pigs weighing 8–30 kg bodyweight, without phytase supplementation, and the six other diets were formulated similar to the PC, except with a reduction in the nPP concentration of 0.065, 0.130 or 0.195% (Phase Feeding 1 (PF1), PF2 or PF3 respectively) or similar to PF1, PF2 and PF3 minus 0.16% Ca, supplemented with 2000 FTU/kg of phytase, with eight replicate pens/Trt of three piglets each, in a three-phase feeding program. From Day 28 to Day 35, the average daily gain was higher (P &amp;lt; 0.05) and the feed conversion rate was lower (P &amp;lt; 0.05) respectively for piglets fed the PC when compared with those fed PF3 and PC treatment minus 0.160% calcium and minus 0.195% nPP (PF6). In contrast, when evaluating the period from Day 28 to 49, piglets fed PC presented the highest average daily gain, but only differed (P &amp;lt; 0.05) to those fed PF3 and PF6. When considering the overall period, at 63 days of age, no significant difference was detected (P &amp;gt; 0.05) between the PF Trts tested and the PC regarding performance. As for bone mineralisation at 63 days, bone P (BP) decreased as nPP in the diet decreased, regardless of the Ca level. However, except for PF3 and PF6, BP and third metacarpal bone ash concentration were respectively higher for pigs fed the PF Trts, when compared with PC. All treatments containing phytase resulted in a lower bone Ca:BP ratio when compared with PC. Serum P concentrations decreased as nPP in the diet decreased, regardless of the level of dietary Ca. However, with the exception of PF3 and PF6, serum P was not significantly different than pigs fed the PC. In conclusion, reducing nPP or nPP and Ca in diets containing 2000 FTU Ronozyme® HiPhos/kg phytase had no adverse effects on growth performance and increased BP and third metacarpal bone ash concentration compared with pigs fed a nutritionally adequate control diet.