Ca Digestibility Research Articles

Phytase and nutrient-energy matrix: a strategic approach to enhancing the performance of broiler chickens fed a corn-soybean meal-based diet.

This study examined the effects of a nutrient matrix with or without phytase on the performance of broiler chicken. A total of 2000 day-old Ross 308 broiler chickens were assigned to 5 dietary treatments, with 10 broilers per replicate and 40 replicates per treatment. The experimental diets included 1. CON: A corn and soybean meal (SBM)-basal diet without phytase. 2, NC1: A corn-SBM-based diet with reduced nutrients, specifically 0.13% less phosphorus, 40 Kcal/kg less metabolizable energy (ME), and 0.30% less crude protein (CP), without phytase. 3, NC1+PHYT: NC1+500 FTU/kg phytase. 4, NC2: Another corn-SBM-based diet with greater nutrient reductions, including 0.16% less phosphorus, 55 Kcal/kg less metabolizable energy (ME), and 0.45% less crude protein (CP), without phytase. 5, NC2+PHYT: NC2+1000 FTU/kg phytase. In the pre-starter and overall phase, feed conversion ratio (FCR) was higher in NC2 and NC2+PHYT. In the starter phase, body weight gain (BWG) was lower in NC2 and NC2+PHYT. In the grower phases, BWG was lower in NC2, while FCR was higher. At d28, the digestibility of ash was higher in NC1+PHYT, while the digestibility of Ca and phosphorus were higher in NC1+PHYT and NC2+PHYT. At day 42, the digestibility of ash, Ca, and phosphorus were higher in NC1+PHYT and NC2+PHYT. The level of tibia ash was lower in NC2. The level of myo-inositol was lower in NC2 at d28, while the level of myo-inositol at d42 was lower in NC1 and NC2. We concluded NC1+PHYT showed a higher growth performance comparable to CON, as against the lower performance observed in NC2, NC2+PHYT, and NC1.

Effects of feed particle size, calcium concentration and phytase supplementation on InsP6 degradation in broiler chickens fed pelleted diets

ABSTRACT 1. The objective of the trial was to study the single and interactive effects of feed particle size in pelleted feed, dietary calcium (Ca) concentration and microbial phytase supplementation in broiler chickens. The studied traits were myo-inositol (1,2,3,4,5,6) hexakis (dihydrogen phosphate) (InsP6) degradation, pre-caecal digestibility of phosphorus (P), Ca and amino acids (AA) and retention of P, Ca and nitrogen (N). 2. Male Ross 308 broiler chickens were housed in metabolism units in groups of 10 and allocated to one of eight diets with seven pen replicates per diet. The 2 × 2 × 2-factorial arrangement included coarse and fine feed particle size (309 or 222 µm), low and high Ca concentration (4.9 and 7.2 g/kg) and without or with phytase supplementation (1,000 FTU/kg). 3. Pre-caecal InsP6 disappearance was higher with coarse than fine feed particle size when no phytase was added (54 vs. 48%) but not when phytase was added (74%; p = 0.046). High dietary Ca feeds decreased pre-caecal InsP6 disappearance (67 to 59%) and P digestibility (65 to 55%; p < 0.001). Gizzard pH was lower with coarse than fine feed particle size and higher with high Ca than low Ca (p < 0.001). Pre-caecal digestibility of most AA was approximately 3.5%-points lower with high Ca without phytase compared to the other treatments (p ≤ 0.047). Coarse feed particle size caused higher pre-caecal AA digestibility than fine particle size (~2%-points; p ≤ 0.031). InsP6 disappearance in the crop increased at high Ca concentration when phytase was added (22 vs. 37%; p = 0.011). 4. Coarser feed particle size in pellets increased gastrointestinal InsP6 degradation and nutrient digestibility, likely owing to effects on the gizzard functions. Additional Ca supply exerted antinutritive effects that was not compensated for by using coarser feed particles.

A Meta-Analysis on Quantitative Calcium, Phosphorus and Magnesium Metabolism in Horses and Ponies.

The aims of the present meta-analysis were (i) to re-evaluate the factorially calculated Ca, P and Mg requirements to replace endogenous faecal losses, taking new data into account, (ii) to identify potential differences between horses and ponies regarding requirements, apparent digestibility, serum levels and renal excretion of Ca, P and Mg and (iii) to investigate the influence of mineral sources, i.e., "inorganic" sources from added mineral salts and "organic" sources from feed plants. For P, the water solubility of "inorganic" sources was taken into consideration. Data on the aforementioned parameters from 42 studies were plotted against intake, similar to the Lucas test for true digestibility and faecal endogenous losses. Within specific intake ranges, data were compared using t-tests and an ANOVA, followed by Holm-Sidak post hoc tests. Ponies had lower endogenous faecal Mg losses than horses. Consequently, apparent Mg digestibility was higher in ponies. Factorial calculations of Mg requirements to replace faecal losses showed that ponies needed approximately half of the current recommended amount, while horses required 1.9 times the amount currently recommended by Kienzle and Burger. The overall mean matched previous recommendations. For Ca, there was no discernible difference between ponies and horses. True Ca digestibility calculated by the Lucas test was higher and endogenous losses were lower when "organic" Ca was fed as opposed to when "inorganic" sources were used. The resulting factorial calculations of the requirements to replace faecal losses were close to current recommendations for "organic" Ca. For "inorganic" sources, however, the new calculations were below the recommended level. For P, there were no discernible differences between horses and ponies. There were also no clear effects of "inorganic" or "organic" P sources. The water solubility of "inorganic" sources was the key factor determining P metabolism. Water-soluble P sources exhibited higher true and apparent digestibility. The intake of these P sources led to hyperphosphatemia and hyperphosphaturia, even at low intakes. In other species, this has been shown to pose a health risk. Therefore, it is recommended to avoid the use of highly water-soluble "inorganic" P sources in horses and ponies. Given the lower digestibility of insoluble P sources, the factorially calculated P requirements for such sources are higher than the current recommendations.

Standardized Ileal Digestibility of Calcium and Phosphorus in Feed Ingredients for 21-Day-Old Broilers.

This study aimed to determine the standardized ileal digestibility (SID) of calcium (Ca) and phosphorus (P) in various feed ingredients using the direct method. This study comprised eight experimental diets: a Ca-P-free diet and seven experimental diets, each containing monocalcium phosphate (MCP), dicalcium phosphate (DCP), monosodium phosphate (MSP) + limestone, corn, and soybean meal (SBM) as the sole sources of Ca and/or P. These diets provided 4.21 g/kg of non-phytate P from MCP, DCP, or MSP, and the MSP + limestone diet included 7.50 g/kg of Ca. The corn and SBM diets formulated to determine P digestibility maintained a dietary Ca/total P ratio of 1.4 through the addition of limestone. Chromic oxide was added to the diets as an indigestible index. On day 18, 256 male and 256 female broilers were individually weighed and randomly assigned to eight treatments, each with four replicates for each sex (eight birds per cage). This allocation followed a randomized complete block design based on body weight. On day 21, the birds were euthanized using carbon dioxide, and ileal digesta samples were collected from the distal two-thirds section of the ileum. No significant interactions between the experimental diets and sex regarding the SID of Ca or P were detected, and no effect of sex on the SID was observed. The standardized ileal Ca digestibility of MCP, DCP, limestone, corn, and SBM was found to be 84.7%, 70.1%, 52.6%, 88.6%, and 81.6%, respectively. The standardized ileal P digestibility of MCP, DCP, MSP, corn, and SBM was determined to be 91.8%, 76.8%, 94.4%, 73.1, and 88.4%, respectively. Given the variable digestibility of Ca and P across different feed ingredients, the consideration of the specific type of ingredients used in diet formulation is crucial.

Apparent digestibility and calcium and phosphorus in urine after feeding different combinations of calcium and phosphorus sources to adult dogs.

The present study aimed to investigate the effect of the combination of a water-soluble calcium (Ca) source (CaCl2) with a water-soluble phosphorus (P) source (NaH2PO4*2H2O, diet soluble, SOL) in comparison to a water-insoluble P source (CaHPO4*2H2O, diet insoluble, INS) on apparent digestibility and renal excretion of Ca and P in dogs. The Ca intake was 226 mg/kg bodyweight (bw), the Ca/P ratio 1.9/1 in SOL and 2.0/1 in INS. The percentage of Ca from CaCl2 was 60% in SOL and 33% in INS. Eight adult Foxhound-crossbred dogs FBI, (3-5 years, bw 24-32 kg) were available. Standard digestion trials were carried out (10 days adaptation, 5 days total faecal collection). Spontaneously excreted urine was collected pre- and postprandially. In vitro water solubility of P in the mineral premixes was determined. The Ca digestibility was negative in both trials without significant differences between the groups. Apparent P digestibility was increased in group SOL (26% vs. 20% in INS). In both groups, P content in urine was higher pre- compared to postprandial, with higher concentrations in group SOL. The same was true for the P/Crea ratio. The water solubility of P in the mineral premixes used in the trials showed considerable differences: The P in premix INS was insoluble in water after 1 and after 90 min. By contrast, the P in the premix SOL was highly soluble (98%) after 1 minute. After 90 min, however, the P solubility decreased to 43%, suggesting the formation of insoluble CaP salts, presumably from CaCl2 and NaH2PO4*2H2O. In conclusion, in the present study, apparent Ca digestibility in dogs was not affected by the solubility of Ca and P, while P digestibility and renal P excretion increased.

Calcium and phosphorus digestibility in broilers as affected by varying phytate concentrations from corn

Dietary phytate P (PP) concentration impacts Ca and P digestibility in broilers. Research was conducted to determine the impact of increasing concentration of dietary PP, with and without phytase, on broiler standardized ileal digestibility (SID) of Ca and P. Digestible (Dig) Ca and P were calculated by multiplying SID and the analyzed dietary Ca and P concentrations. The experiment was a factorial arrangement of 2 phytase (0 and 1,000 U/kg) and 4 PP (0.16, 0.23, 0.29, and 0.34%) concentrations. Treatments were fed for 36 h from 20 to 22 d of age (4 b/pen, n ≥ 7 replicate pens/treatment). Different ratios of corn and corn germ were used to achieve the desired PP concentrations. A limestone with 800 µm geometric mean diameter was used as the sole Ca source to achieve 0.7% Ca in the final diets (96% Ca from limestone). An additional diet was fed that was N, Ca- and P-free, for the determination of endogenous losses of each nutrient. Distal ileal digesta were pooled from all birds in a pen. There were no interactions between PP and phytase on SID Ca or Dig Ca from limestone. Irrespective of phytase inclusion, increasing PP from 0.16 to 0.34% decreased SID Ca from 53.8 to 38.1% (P < 0.05). The SID Ca averaged 41.5 and 51.4% in diets containing 0 and 1000 U phytase/kg, respectively, across all PP concentrations (P < 0.05). Interactions were seen between PP and phytase on SID and Dig P (P < 0.05) with SID P of 31.1, 24.0, 20.1, and 16.3% for broilers fed 0.16, 0.23, 0.29, and 0.34% PP diets without phytase, respectively. When phytase was included at 1000 U/kg, SID P was 89.9, 87.5, 73.9 and 60.4% for diets containing 0.16, 0.23, 0.29 and 0.34% PP, respectively (P < 0.05). Overall, phytase improved SID Ca and P independent of PP concentration. However, with increasing PP concentration, both SID Ca and P were negatively affected.

256 Anchor Talk: Accounting for effects of microbial phytase on digestibility of calcium and phosphorus

Abstract Inclusion of increasing levels of microbial phytase in diets for weanling and growing pigs results in a linear increase in the standardized total tract digestibility (STTD) of Ca and P. In many experiments, maximum effects on STTD of Ca and P were obtained with inclusion of around 1,200 phytase units (FTU) per kg of diet, although some of the newer phytases appear to release Ca and P until at least 2,000 FTU is included in the diets. In most individual feed ingredients and most practical diets, the maximum standardized total tract digestibility (STTD) of P that is obtained by using between 500 and 1,000 FTU per kg diet is around 70%, whereas the STTD of Ca for some ingredients can be over 80% if microbial phytase is used. One reason for the decreased STTD of P than of Ca in diets with maximum dosages of phytase is that dietary Ca prevents some P from being absorbed, and the STTD of P in practical diets, therefore, will never be 100% regardless of phytase inclusion. It is, however, important that the increased STTD of dietary Ca that is caused by phytase is taken into account in diet formulation because of the negative effects of Ca on STTD of P. In addition, at low dietary phytase there is release of more Ca than P, whereas at greater inclusion levels of phytase, there may be a similar release of Ca and P. Release of Ca and P by phytase is also impacted by ingredient composition in the diets because phytase does not have the same effect on all ingredients. In general, ingredients with low concentration of phytate have greater STTD of P if no phytase is used than ingredients with greater concentrations of phytate P, but the response to phytase is greater for ingredients with high concentrations of phytate. Sows also have lower digestibility of Ca and P than growing pigs and the response to phytase in diets for sows is less than in diets for growing pigs. Likewise, there is a linear reduction in phytase effects on STTD of both Ca and P as pigs get older. In contrast, in diets for newly weaned pigs there are specific advantages to using high concentrations of phytase (at least 2,000 FTU) because gastric pH is reduced in diets with phytase, which results in less diarrhea. This effect may be related to increased concentrations of plasma inositol in pigs fed diets with phytase, which may positively impact the immune status of the pigs. In conclusion, use of phytase in diets for pigs results in increased STTD of Ca and P and may have other benefits as well.

263 Effects of source of calcium carbonate and microbial phytase on standardized total tract digestibility of calcium by growing pigs

Abstract The objective of this experiment was to test the hypothesis that there are differences in the standardized total tract digestibility (STTD) of Ca and in response to microbial phytase among sources of calcium carbonate obtained from different regions of the world. Barrows [n = 320; average body weight (BW) = 17.47 kg; SD = 1.28] were allotted to 40 diets using a completely randomized block design with eight blocks of 40 pigs for a total of eight replicate pigs per diet. All diets were based on corn and potato protein concentrate. Twenty sources of calcium carbonate were obtained from different regions of the world, including the United States, Europe, Asia, and South Africa. Each source of calcium carbonate was used in two diets, one diet without microbial phytase and one diet that contained 1,000 phytase units/kg diet. Pigs were housed individually in metabolism crates. Pigs were provided feed at 3.0 times the maintenance requirement for energy. Feces were collected for 4 d following the adaptation period after 5 d of adaptation. Fecal samples were dried, ground, and analyzed for Ca to calculate the digestibility. The initial statistical model included calcium carbonate source, phytase, and the Ca-source × phytase interaction as fixed effects; however, no interactions between Ca source and phytase were observed. Therefore, the final statistical model included only Ca source and phytase as fixed effects. A second analysis was performed to compare the digestibility of Ca in calcium carbonate obtained from different regions of the world (i.e., Europe, Asia, the United States, and South Africa). In this model region, phytase, and the region × phytase interaction were fixed effects. However, no interactions between region and phytase were observed and therefore, the final statistical model included only region and phytase as fixed effects. Concentrations of Ca in the 20 sources of calcium carbonate ranged from 32.1 to 40.9% (Table 1). Differences in the STTD of Ca were observed among pigs fed diets containing different sources of calcium carbonate (P &amp;lt; 0.001). Pigs fed diets containing 1,000 units of phytase had greater (P &amp;lt; 0.001) STTD of Ca compared with pigs fed diets containing no phytase. The STTD of Ca in calcium carbonate from the United States was less (P &amp;lt; 0.001) than in calcium carbonate from Europe, Asia, or South Africa. In conclusion, the use of microbial phytase increases the STTD of Ca in calcium carbonate, but the STTD of Ca varies among different sources and among sources from different regions. Therefore, consideration should be given to differences in analyzed concentrations of Ca, values for STTD of Ca, and response to microbial phytase among different sources of Ca carbonate to ensure Ca is not being oversupplied when formulating diets.

PSI-11 Determination of standardized total tract phosphorus digestibility in expeller-pressed Canadian prairie grown soybean meal fed to growing pigs

Abstract The objectives of this study were 1) to determine the apparent total tract digestibility (ATTD) of calcium (Ca) and phosphorous (P) and standardized total tract digestibility (STTD) of P in soybean expeller (SBE), and 2) to examine the effects of microbial phytase supplementation on ATTD and STTD of P in SBE. A total of 48 growing barrows (body weight = 15.5 ± 0.7 kg, mean ± SD) were assigned to 1 of 8 dietary treatments (4 with 500 phytase units/kg and 4 without phytase) in a completely randomized design to give 6 replicates per treatment. SBE was the only source of P in diets. Four SBEs were used in the experiment, with three derived from soybeans grown in Manitoba (MB1, MB2, and MB3) whereas the fourth was derived from soybeans grown in Ontario. The experiment was conducted over 3 consecutive 12-d periods; within each period the initial 7 d were for adaptation followed by 5 d for total fecal collection (marker to marker procedure). Data were analyzed using the MIXED procedure of SAS. Fixed effects were the type of SBE and phytase whereas period was included as a random effect in the model. Dry matter (DM), Ca and P content was analyzed in diets and feces. The ATTD and STTD of P were not affected by the source of SBE and averaged 63.0% and 69.9%, respectively. Phytase supplementation significantly increased (P &amp;lt; 0.001) P digestibility in all SBE types. The ATTD and STTD values of P with phytase supplementation averaged 72.8% and 79.7%, respectively. There was no interaction effect between type of SBE and phytase supplementation. The ATTD of Ca (P &amp;lt; 0.001) in MB2 was significantly less (55.7%) than in the other SBEs whose values averaged71.6%. Ca digestibility was not affected by phytase inclusion. In conclusion, the ATTD and STTD of P were not different among the SBE types. Phytase supplementation increases the P digestibility in SBE irrespective of source.

PSV-14 Determination of optimal digestible phosphorus level in lactating sows

Abstract Optimal dietary phosphorus (P) is important for sows, not only to maintain P homeostasis and prevent premature culling due to lameness and locomotion, but also to support growth of their offspring. The objective of this experiment was to determine the optimal level of digestible P in lactating sows for the best reproductive performance and piglet growth. A total of 550 gestating sows were enrolled using a randomized block design with sow parity and group as blocks. Sows with an entry body weight of 247.5 ± 29.1 kg were allotted to one of the five levels of digestible P (similar as standard total tract digestibility of P with consideration of phytase released P): 0.2%, 0.3%, 0.4%, 0.5% and 0.6%. A corn-soy-wheat middling based lactation diet was formulated with phytase inclusion (550 FTU/kg) and a fixed ratio between calcium (Ca) and digestible P of 2.5. All diets were formulated to have the same nutrient levels except 69 kcal net energy difference between 0.6% and 0.2% digestible P treatments due to slight difference in the ingredient composition. Experimental diets were fed approximately 4 d before farrowing and throughout the entire lactation (21 d). Feces were collected from 20 sows per treatment around 14 d of lactation to measure apparent total tract digestibility (ATTD) of Ca and P. Using R (version 4.0.0), performance and digestibility data were analyzed using a general linear model and a generalized linear model specifying a binomial distribution was deployed for count data. Dietary treatments did not impact sow average daily feed intake or piglet birth and weaning weights (Table 1). However, dietary treatments affected piglet livability (P &amp;lt; 0.05) and pre-weaning morality (P &amp;lt; 0.01), with 0.5% digestible P having the greatest livability and 0.4% digestible P having the least pre-weaning mortality. There was a positive linear dose effect of digestible P on probability of weaned pigs (P &amp;lt; 0.05). Dietary digestible P affected ATTD Ca (88.8 ± 3.1%, P &amp;lt; 0.01) and ATTD P (64.4 ± 6.5%, P &amp;lt; 0.01) in sows on d14 of lactation, with greater digestible P leading to decreased ATTD Ca and P. In conclusion, dietary digestible P level affected ATTD Ca and P during lactation. Digestible P level of 0.4% and greater led to greater piglet livability and resulted in greater probability of weaned pigs.

54 Effects of a new biosynthetic 6-phytase supplementation on nutrient digestibility, phytate disappearance and growth efficiency in weaning piglets fed low in calcium and digestible phosphorus diets

Abstract The objective of this study was to investigate the influence of adding graded levels of a new biosynthetic bacterial 6-phytase on nutrient digestibility, phytate disappearance and growth performance in weaned piglets. A total of 192 male weaned piglets with initial body weight of 8.70 ± kg, distributed in a randomized block design with four treatments and 24 replicate pens with 2 animals each for 42 d. The experimental diets included a phosphorus and Ca deficient diet (STTD of P/Ca = 0.21%/0.58% and 0.19%/0.54%, respectively, in post-weaning 1 and 2 diets) containing 0 (a control diet), 500, 1,000 or 1,500 FTU/kg diet. The diets were fed into 2 phases: post-weaning 1 and 2 from 1 to 14 and 15 to 42 d, respectively. Body weight and feed intake were measured at the end of each phase, and average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) were calculated for the overall experimental period. On d 42, ileal digesta samples were collected from 1 piglet/pen (n = 12 samples/treatment) for apparent ileal digestibility (AID) of Ca, P, and amino acids and phytate disappearance determination. Supplementation of diet with phytase from 0 to 1500 FTU/kg diet linearly improved (P &amp;lt; 0.01) AID of Ca. Both linear and quadratic effects (P &amp;lt; 0.001) was observed for AID of P and phytate-P. Increasing level of phytase supplementation resulted in linear and quadratic increases of Arg, His, Ile, Leu, Lys, Phe, Thr, Trp, Val, Ala, Asp, Cys, Glu, Ser, Tyr and total amino acids. Phytase supplementation increased (P &amp;lt; 0.0001) linearly Met and Pro, with an AID of Met showing a tendency (P = 0.09) for a quadratic increase. In addition, increasing phytase dose linearly increased (P = 0.006) the overall ADFI and ADG and decreased (P &amp;lt; 0.001) F:G ratio. Also, a tendency (P = 0.07) for quadratic effect of phytase was also observed on F:G ratio. These findings highlight that the supplementation of diets with the new bacterial 6-phytase significantly enhanced the utilization of nutrients, disappearance of phytate and performances of weaned piglets in a dose dependent manner.

260 Effect of different doses of phytase (HiPhorius) and two primary calcium sources on nutrient digestibility, retention and blood parameters in weaned piglets

Abstract An 18-d study evaluated the effect of increasing phytase levels in diets with limestone or Ca-formate on Ca and P digestibility, P retention, and blood inositol, Ca, and P in weaned piglets. At weaning, male piglets [n = 60; 29.8 ± 1.10 d of age; initial body weight (BW) = 8.8 ± 0.31 kg) were randomly allocated to ten diets formulated as a 2 × 5 factorial design with 2 primary Ca sources (limestone or Ca-formate) and 5 Ca/P levels. There was a positive control diet (PC; 0.76% Ca, 0.34 dP) and 4 negative control diets (NC; 0.56% Ca, 0.34% dP) supplemented with phytase at 0, 750, 1,500, and 3,000 FYT/kg. At d 10, piglets were individually housed in metabolism crates and fed 3.2 x metabolic weight. On d 14 to 18, fecal and total urine samples were collected. Apparent total tract digestibility (ATTD) was calculated for dry matter (DM), organic matter (OM), crude protein (CP), ash, Ca, and P using TiO2 as marker. Urinary P was measured to calculate P retention. These data were analyzed as a 2-way interaction. On d 0 (baseline), 8 and 18, blood samples were collected to analyze serum Ca and P, and plasma inositol. Blood data were analyzed as a 3-way interaction. Results indicated that piglets fed Ca-formate had greater ATTD of Ca (75.0% vs. 71.4%, P &amp;lt; 0.01) but decreased ATTD of P (66.4% vs. 68.8%, P &amp;lt; 0.01), than piglets fed limestone. Phytase supplementation improved ATTD of DM, ash, OM, CP, P, and Ca compared with the NC and PC. An interaction between Ca/P levels and Ca-sources was observed for urinary P (P = 0.03), as there were no differences between Ca sources in piglets fed the NC or the 750 FYT diets, but piglets fed the PC diet and the NC+1,500 or 3,000 FYT with limestone had greater urinary P compared with Ca-formate. A 2-way interaction between Ca/P levels and d was observed for plasma inositol (P = 0.012). On d 8 and 18, there was no difference between the NC and PC;, however, phytase supplementation at 750, 1,500, and 3,000 FYT increased plasma inositol on d 8 (58.2, 80.7, and 89.5 μmol) and d 18 (70.2, 85.4, and 106.4 μmol). There was only a main effect of Ca/P levels in serum P. Compared with the NC (73.7 mg/L), the PC and the NC+750, 1,500, and 3,000 FTU/kg increased serum P (90.3, 89.1, 87.6, and 93.2 mg/L, respectively, P &amp;lt; 0.01). There was no effect of Ca source on blood inositol and P. No significant dietary treatment effects were observed in serum Ca. In conclusion, using Ca-formate instead of limestone increases Ca digestibility but reduces P digestibility, likely due to a greater Ca solubility of Ca-formate. This suggests that diets should be formulated based on digestible Ca instead of total Ca.

Effects of Feeding Recycled Food Waste-Based Diets on Gut Health, Nutrient Digestibility, and Bone Quality in Laying Hens

This study explored feeding recycled food waste-based diets for gut health, nutrient digestibility, bone morphology, and bone mineral level in laying hens. Hy-Line Brown laying hens (n = 150) were randomly allocated to three experimental treatments consisting of a commercial control diet, a recycled food waste-based diet, and a 50:50 blend of the control and food waste-based diets, with 50 replicates of a single bird per cage per treatment from 24 to 63 weeks of age. Egg production was recorded daily and feed intake was measured weekly. The gut pH, jejunal and ileal morphology, nutrient digestibility, bone morphology, and mineral composition were measured at 63 weeks of age. Hens on the food waste-based treatment had similar egg production but lower feed conversion ratio (FCR, 1.948 vs. 2.172 kg feed/kg egg, p &lt; 0.001) and higher ileal pH (p &lt; 0.001) and bone ash content (p &lt; 0.001) compared to birds on the control treatment. Moreover, hens fed the food waste-based diets had higher ileal digestible energy (p &lt; 0.001); ileal energy digestibility (p &lt; 0.01); tibia S, Fe, Mn, and Zn levels (p &lt; 0.05); and Mg, K, S, Mn, and Mo digestibility (p &lt; 0.05) compared to hens fed the control diets. Hens offered the 50:50 blend diets had higher tibia P, Mg, and Mo levels (p &lt; 0.05) and higher Ca digestibility (p &lt; 0.05) compared to those fed the control diets. Thus, feeding recycled food waste-based diets is effective to improve laying performance, nutrient digestibility, and bone mineralization in laying hens.

Conch Shell (Turbinella pyrum) Powder: A Potential Marine Biological Source of Calcium and Some Trace Minerals for Growing Crossbred Calves.

The present study was conducted to evaluate the effect of feeding conch shell (Turbinella pyrum) powder (either fresh or calcined) as a marine organic source of calcium (Ca) supplemented in the diet of crossbred calves on voluntary intake, growth performance, and blood biochemistry in growing crossbred Jersey calves. A growth trial of 90days was conducted on 15 Jersey crossbred female calves (Av. weight, 70.68 ± 2.90kg; Av. age, 197.73 ± 12.40days), equally divided into three groups of 5 animals each, i.e., control (T0), treatment 1 (T1), and treatment 2 (T2). All animals were fed total mixed ration (TMR) prepared with a concentrate mixture, chaffed paddy straw, and green fodder at the ratio of 40:30:30 on DM basis. Calves under the control group were fed with TMR containing a standard mineral mixture having dicalcium phosphate (DCP) as a Ca source. Calves under T1 group were supplemented with TMR containing fresh conch shell powder (FCSP), and T2 calves were fed with TMR containing conch shell calcined powder (CSCP) as Ca source. We observed 11.66% increase (p < 0.01) in Ca concentration in CSCP compared to FCSP. The concentration of minerals like Mg, Co, Mn, and Fe was enhanced in CSCP compared to the FCSP. However, the calcination process of fresh conch shell powder (FCSP) reduced the concentration of Cu, and Zn. The Ca/P ratio was estimated as 2.11, 2.06, and 2.10 in T0, T1, and T2 diets, which could be considered ideal for calf ration. Calves under T1, and T2 groups consumed significantly (p < 0.001) greater amounts (g/kg W0.75) of DM and CP compared to T0. However, increased voluntary intake did not translate into increased body weight gain (kg), and feed conversion ratio (kg DMI/kg gain) in T1 and T2 groups in comparison to T0. We observed similar blood glucose, urea, alkaline phosphatase (ALP), aspartate aminotransferase (AST), and alanine transaminase (ALT) concentration among the three treatments. Ca, and P levels in blood plasma were also identical among the three groups. The digestibility of Ca was increased significantly (p = 0.01) in FCSP (T1)- and CSCP (T2)-treated calves compared to control (T0) calves. Similarly, T1 and T2 enhanced P digestibility compared to T0. This first report with short-term experimentation depicted some promising scope for the use of locally available conch shell powder (fresh or calcined form) as a potential source of Ca for feeding to livestock, because these new sources of Ca did not affect intake, digestibility of Ca and P, growth performance, blood chemistry, and liver enzymes negatively in weaned crossbred calves.

Effect of Including Noni Leaves Meal into Basal Diet on Ca and P Intake and Digestibility in Landrace Crossbred Pig

The study aimed at evaluating the effect of including noni meal leaves (TDM) into basal diet on Ca and P intake and digestibility in landrace crossbred pig. Data intake and feces collection was carried out for 2 weeks. There were 12 male piglets 1-2 months of age with 10.50-21.50 (average 16.70) kg (CV 18.76%) initial body weight used in the study. Randomized block design 4 treatments with 3 replicates procedure was applied in the trial. The treatment diets offered were: R0: 100% basal diet without TDM; R1: 98% basal diet + 2% TDM; R2: 96% basal diet + 4% TDM; and R3: 94% basal diet + 6% TDM. Variable evaluated were: intake and digestibility of Ca and P in pig. Statistical analyisis found that including noni leaves meal is not significant (P&gt;0.05) in increasing either intake or digestibility of either Ca or P in pig. The conclusion is that including 2, 4, 6 % noni leaves into basal diet tends to increase both intake and digestibility of both Ca and P in pigs.

Dietary of different forms of Humulus scandens on growth performance and intestinal bacterial communities in piglets.

The present study was aimed at elucidating the effects of feeding different forms of Humulus scandens (Hu) on performance and bacterial communities in piglets. A total of 160 piglets were divided into four groups: (1) a control (CG, basal diet); (2) a basal diet with Hu pulp (HS), basal diet + Hu pulp; (3) a basal diet with Hu juice (HSJ), basal diet + Hu juice; and (4) a basal diet with Hu residue (HSR), basal diet + Hu residue. Results showed that HS, HSJ, and HSR supplementation led to rich average daily gain (ADG) and poor feed conversion ratio (FCR) during 28 to 70 d of age, increased 120 d body weight (BW), average daily feed intake (ADFI) and ADG and decreased FCR during 71 to 120 d of age. Three experiment groups presented greater (P < 0.05) IgA, IgG, and IgM and lower (P < 0.05) glucose, and blood urea nitrogen. The content of diamine oxidase significantly decreased (P < 0.05) in HS group. The crude protein and crude fiber digestibility were improved (P < 0.05) in HS group and the Ca digestibility was increased (P < 0.05) in HS and HSJ groups. HSR supplementation improved the abundance of Firmicutes and decreased the abundance of Bacteroidetes. Hu supplementation with different forms increased the proportion of Lactobacillus in cecum content. These results indicated that supplemental feeding of Hu with different forms improved serum immunity, nutrient digestibility, and bacterial communities in piglets, promoting growth and development, which may be regarded as a reference for developing novel feed resources for piglets.

Amino acid and mineral digestibility, bone ash, and plasma inositol is increased by including microbial phytase in diets for growing pigs

BackgroundThe effect of microbial phytase on amino acid and energy digestibility is not consistent in pigs, which may be related to the phytase dosage or the adaptation length to the diet. Therefore, an experiment was conducted to test the hypotheses that increasing dietary phytase after an 18-day adaptation period: 1) increases nutrient and energy digestibility; 2) increases plasma P, plasma inositol, and bone ash of young pigs; and 3) demonstrates that maximum phytate degradation requires more phytase than maximum P digestibility.ResultsData indicated that increasing inclusion of phytase [0, 250, 500, 1,000, 2,000, and 4,000 phytase units (FTU)/kg feed] in corn-soybean meal-based diets increased apparent ileal digestibility (AID) of Trp (quadratic; P < 0.05), and of Lys and Thr (linear; P < 0.05), and tended to increase AID of Met (linear; P < 0.10). Increasing dietary phytase also increased AID and apparent total tract digestibility (ATTD) of Ca and P (quadratic; P < 0.05) and increased ATTD of K and Na (linear; P < 0.05), but phytase did not influence the ATTD of Mg or gross energy. Concentrations of plasma P and bone ash increased (quadratic; P < 0.05), and plasma inositol also increased (linear; P < 0.05) with increasing inclusion of phytase. Reduced concentrations of inositol phosphate (IP)6 and IP5 (quadratic; P < 0.05), reduced IP4 and IP3 (linear; P < 0.05), but increased inositol concentrations (linear; P < 0.05) were observed in ileal digesta as dietary phytase increased. The ATTD of P was maximized if at least 1,200 FTU/kg were used, whereas more than 4,000 FTU/kg were needed to maximize inositol release.ConclusionsIncreasing dietary levels of phytase after an 18-day adaptation period increased phytate and IP ester degradation and inositol release in the small intestine. Consequently, increasing dietary phytase resulted in improved digestibility of Ca, P, K, Na, and the first 4 limiting amino acids, and in increased concentrations of bone ash and plasma P and inositol. In a corn-soybean meal diet, maximum inositol release requires approximately 3,200 FTU/kg more phytase than that required for maximum P digestibility.

Impact of enzyme inclusion on the digestibility of protein, amino acids, calcium and phosphorus in growing pigs depending on meal size, frequency and sampling period

When digestibility trials are conducted, pigs are typically fed twice a day with a restricted amount of feed. These conditions are not representative of the feeding conditions in commercial farm. The present study aimed to determine the effects of meal size and frequency, xylanase and phytase inclusion as well as digesta sampling period, on the digestibility of protein, amino acids (AA), calcium (Ca) and phosphorus (P). Pigs (n = 6) were fitted with a T cannula, and each received all treatments following a 2 × 3 factorial arrangement in a 6 × 6 Latin square experimental design. The diets were supplemented or not with a combination of xylanase and phytase and divided into 3 feeding programs: one received 2 meals per day that met 3 times the maintenance energy requirement (2M), one received the same quantity of feed in 8 meals (8M), and another received an amount that supplied 5 times the maintenance energy requirements in 8 meals (8M+). Digesta was sampled from 0800 to 1200, 1200–1600, 1600–2000 and 0800–2000. The results indicated an improvement in the coefficient of apparent ileal digestibility of dry matter, crude protein, P, Ca, Val and Thr with enzyme inclusion in all meal distribution (enzyme effect, P < 0.05). Apparent ileal digestibility of Ca in the 0800–1200 period was reduced in 8M+ treatment compared to 2M and 8M whereas no difference was observed for meal size or frequency in 1200–1600 and 1600–2000 periods (Interaction meal × period, P = 0.017). A meal effect was observed for coefficient of apparent total tract digestibility of Ca (meal effect, P = 0.003) which was higher by 8% in pigs fed 8M compared to 8M+ (contrast 8M vs 8M+, P = 0.040). Saturation of the absorption processes may explain lower digestibility with 8M+ . Enzyme efficacy was not affected by meal size or frequency indicating minor modifications of digestive conditions. An 8-h sampling period would allow collection of a representative sample and avoid underestimating or overestimating digestibility of certain nutrients.

Ileal mineral digestibility and expression of nutrient transporter genes of broiler chickens in response to variable dietary total Ca and phytase supplementation are influenced by time on experimental diet and age of the birds

Two experiments were conducted to determine the impact of Ca, phytase, sampling time, and age on the digestibility (AID) of Ca and P and the expression of their transporters. Cobb 500 male chicks (N = 600) were used in each experiment and allocated to cages with 10 (Exp 1, 8-11 d) or 5 (Exp 2, 21-24 d) birds/cage and 10 (Exp 1) or 20 (Exp 2) reps/treatment. Treatments were a 2 × 3 factorial arrangement, with low (LOW) or standard (STD) Ca level and 3 phytase (PHY) levels (0, 300, or 3,000 FYT/kg). Ileal digesta were collected at 8, 12, 24, 48, and 72 h, and jejunum tissues at 12, 48, and 72 h after the start of feeding experimental diets. In Exp 1, there was no effect of Ca or phytase on the AID of Ca at 8, 12, or 24 h. Phytase increased the AID of P (P < 0.05) at all time points, and the magnitude was influenced by Ca. At 12 h, the mRNA level of P (NaPi-IIb) and Ca (CaSR) transporters was greatest in the LOW diets without phytase (Ca × PHY, P ≤ 0.06). In Exp 2, the STD diet decreased the AID of Ca and P (P < 0.05) at 8, 24, 48, or 72 h. Phytase increased the AID of Ca (P < 0.05) at 8, 12, and 24 h, and decreased the AID of Ca (quadratic, P < 0.05) in the STD diet (48 h). The AID of P (P < 0.05) increased with phytase at all sampling times. At 48 h, 3,000 FYT/kg decreased (P < 0.05) mRNA expression of NaPi-IIb and Ca transporter ATP2B1 in the STD diet (Ca × PHY, P < 0.05). In conclusion, to avoid adaptation of broilers to Ca and P deficiencies, the optimal time on experimental diets is ≤ 48 h for young broilers and ≤ 24 h in older birds due to up- or down-regulation of Ca and P transporters in response to dietary Ca, P, and phytase.

Effect of day-old chick weight on the response of broilers to high doses of exogenous phytase

A total of 360 Ross 708 male broiler chicks were used in an 8 treatment and 9 replicate cage study to explore the influence of day-old chick weight on the efficacy of exogenous phytase. Treatments were arranged as a 2 × 4 factorial with the factors being diet (a positive (PC) and negative control (NC) varying in nutrient density fed without or with 2 concentrations of exogenous phytase) and chick weight (light; <38.5 g or heavy; >42 g). Chicks were sourced from the same breeder flock, with light and heavy chicks being selected from the naturally occurring heterogeneity in the population. The diets were corn-soybean meal based and the PC was formulated to meet the nutrient requirements of male broiler chicks. The NC was formulated to contain 120 kcal/kg, 0.5, 0.18, and 0.18% less apparent metabolizable energy (AME), crude protein (CP), calcium (Ca), and phosphorus (P), respectively, than the PC. Amino acid (AA) density in the NC was also reduced in line with the reduction in CP and the manufacturers' recommendations for the effect of phytase on amino acid digestibility. Phytase at either 1,000 FYT/kg or 3,000 FYT/kg was added only to the NC to create a total of 4 diets. Water and mash feed were available ad libitum and were offered to 8 replicate cages, each containing 5 chicks. The experiment was conducted over a period of 3 wk and diets were offered in 2 phases (starter from d 1 to 10 and grower from d 11 to 21). Growth performance was monitored at the end of each diet phase and on d 21 ileal digesta were collected for estimation of apparent digestibility of energy (DE), nitrogen (N), Ca, P, dry matter (DM), and AA. There were no statistically significant interactions between diet and day-old chick weight for any of the measured parameters. Light chicks had significantly lower weight gain (approx. 5%) at both d 10 and d 21 compared with heavy chicks. This effect was principally associated with reduced feed intake and there was no significant effect of chick weight on feed conversion ratio (FCR). Chick weight had no effect on ileal nutrient digestibility. The reduction in nutrient density from the PC to the NC generated a significant reduction in weight gain (around 12%) and a significant increase in FCR (1.68 vs. 1.83). This effect was associated with a significant reduction in ileal DE (approximately 150 kcal/kg) and in the digestibility of several AA. Exogenous phytase significantly increased weight gain, reduced FCR and generated a significant increase in the ileal digestibility of energy, N, P, and several AA. Although chick weight and diet did not interact statistically, heavy chicks benefited more than light chicks from high doses of exogenous phytase across almost all measured end points which was confirmed by regression analysis. In conclusion, light chicks have inferior performance outcomes than heavy chicks principally because of reduced feed intake, but putatively not in digestive capacity per se. Exogenous phytase is effective in improving performance and nutrient digestibility in nutrient deficient diets. The effect of chick weight per se, and also breeder flock age, on the utility of supra-nutritional inclusion concentrations of exogenous phytase warrants further study.