Pig Bone Research Articles

Comprehensive spectroscopic and morphological analysis of the effects exerted by different acids on Pig bone: Forensic aspect

Demineralization of the chemically treated pig shoulder bone in hydrochloric, hydrofluoric, and acetic acid was monitored by ATR-FTIR, Raman, and LIBS spectroscopies and SEM-EDX technique. SEM-EDX analysis showed reduced calcium and phosphorus content after the treatment with acids and erosion of the overall morphology of the bone compared to the sample kept in water. Alterations in bone structure during the 14-day-long immersion in acid solutions indicated significant chemical changes in the obtained spectra. Fourier deconvolution applied in the amide I (1700–1600 cm−1), phosphate (900–1200 cm−1), and carbonate (500–650 cm−1) region indicated the presence of different components in the bone sample, depending on the environment and acid concentration, providing information about the composition. Parameters such as mineral-to-matrix ratio, crystallinity index, and carbonate-to-phosphate ratio were calculated and compared using ATR-FTIR and Raman data. These parameters were also correlated with calcium ionic-to-atomic and phosphorous-to-carbon line intensities obtained from LIBS spectra. Calcium and phosphorus atomic contents obtained by SEM-EDX analysis were in agreement with LIBS data. The results suggested that an increase in acid concentration has primarily affected the phosphate band’s intensity and structure, as the phosphate content was more susceptible to demineralization. Hydrochloric acid was proven to be a more powerful demineralization agent than hydrofluoric and acetic acids. The results of this study could be further applied to the investigation of the bone remains at the crime scene, especially when their removal is attempted by immersion in acid solutions.

From Structure to Strength: Analyzing the Impact of Sulfuric Acid on Pig Bone Demineralization Through FTIR, LIBS, and AAS.

The present research aimed to investigate the demineralizing effects of sulfuric acid on pig bone. Alterations in collagen and phosphate contents and changes in the elemental composition of the bone during the 14-day-long immersion in sulfuric acid solutions of different concentrations were estimated using ATR-FTIR, LIBS, and AAS. FTIR spectra at amide I (1800-1600 cm-1) and phosphate ν1/ν3 (PO43-) (1300-900 cm-1) domains were scrutinized using the deconvolution method for monitoring changes in the protein secondary structure and mineral content. The results implicated sulfuric acid as a powerful demineralization agent and effective in targeting mineral components, such as hydroxyapatite, while leaving the collagen matrix relatively preserved with a complex secondary structure. Collagen maturity marker values gave valuable insights into the structural integrity of the bone. LIBS and AAS indicated changes in bone hardness; phosphorous-to-carbon ratio; and calcium, phosphorous, and magnesium content in the solutions left after the immersion period. The changes in the ratio of ionic-to-atomic calcium lines in the LIBS spectra indicated hardening of the bone, with increasing acid concentration and prolonged action, due to the deposition of calcium sulfate on the surface. The calcium concentration in the solutions decreased with increased acid concentration, while the change in phosphorus and magnesium concentrations was reversed.

Study on the stability, functional activity and preservation effect of oregano essential oil Pickering emulsion with different proportions of chicken bone gelatin/bacterial cellulose during storage

In this study, chicken bone gelatin (CBG) was extracted as a new substitute for traditional pig bone gelatin, and bacterial cellulose (BC) was used as the compound to prepare Oregano essential oil (OEO) Pickering emulsion. To explore a protein/polysaccharide emulsion system that can effectively prolong the functional activity of OEO during storage. The results indicated that the variation in CBG and BC content significantly influenced the physicochemical properties of the emulsions. The optimal formulation of OEO Pickering emulsion, prepared with a CBG-BC ratio of 6:2 (v/v), exhibited superior characteristics including appearance, encapsulation efficiency, and stability during preservation. After 7 d of storage at 4 °C, the rheological properties remained stable, with no significant differences observed in antioxidant and antibacterial activities. It was verified in the beef fresh-keeping experiment that the shelf life of beef samples in the 6-2-2 treatment group was 6 d longer than that in the control group and 3 d longer than that in the pure OEO group. This experiment enhanced the utilization of poultry by-products and provided a valuable reference for exploring suitable protein-polysaccharide systems embedding active substances for food preservation.

Factual observations of dynamic bone crushing

Dynamic bone-crushing, exemplified by the pig bone rib, is characterized thermo-mechanically in relation to the bone’s microstructural characteristics. The cortical bone’s dominant role consists of shielding the trabecular component by resisting deformation, sustaining high load levels, and ultimately cracking. Here we present a qualitative factual study to show that this behavior is the absolute opposite of its quasi-static counterpart in which the trabecular bone was found to play the dominant role. Using infrared thermography, we observed for the first time a significant localized temperature rise of up to 11 degrees Celsius in both cortical and trabecular damaging regions. Such observations call for additional clinically oriented research. Such a high contrast between static and dynamic failure mechanisms was not reported previously, and it paves the way for forensic-oriented studies in which the nature of the sustained load must be determined.

A Systems-Level Analysis of 2-[18F]FDG PET in Pigs Reveals Complex Skeletal Metabolism Networks in vivo which are altered with Osteomyelitis

Our understanding of complex tissue interactions at a systems level remains rudimentary, limiting our ability to dissect mechanisms underlying diseases and develop novel therapeutics. Skeletal research has focused on the pathogenicity of obesity and diabetes mellitus on the skeleton; however, it has been recently revealed that the skeleton is not merely an endocrine target but also a secretory organ, modulating systemic energy homeostasis1,2. We recently discovered that different bones within the murine skeleton have a unique glucose metabolism and form a complex metabolic network3. Thus, we hypothesised that different bones within the porcine skeleton would have unique molecular signatures and form a distinct metabolic network, and these networks would be altered by osteomyelitis, an inflammatory condition of the bone. Five healthy mini and three Danish Landrace-Yorkshire pigs (inoculated with S. aureus to induce osteomyelitis) underwent static 2-[18F]FDG PET/CT and were analysed to measure bone and bone marrow adipose tissue (BMAT) glucose metabolism. Analyze was used for image analysis and processing. Bone and bone marrow volumes of interest were segmented in CT images using Hounsfield Unit (HU) > 300 (bone) and HU -200 to 115 (BMAT; Fig1). PET images were used to extract average standard uptake values. Network analysis was performed using Graphia. Osteomyelitis pigs had a lower bone density and increased BMAT volume compared to healthy controls. There was an increased incorporation of 2-[18F]FDG into the bone and BMAT of osteomyelitis pigs. Similar to what has previously been observed in the mouse3 and human4, there was an increased incorporation of 2-[18F]FDG in the axial skeleton compared to the appendicular skeleton. Network analysis indicated a shift in bone metabolic profiles between healthy and osteomyelitis pigs. Please click on the 'PDF' for the full abstract!

Jaw bone changes in panoramic radiography in patients with hyperparathyroidism

Background and aims: The current investigation aimed to evaluate jaw bone changes, and compare the presence of gonial cortex bone thickness, mental index (MI), lamina dura (LD), lower dental canal, and bone density in panoramic radiography, in patients with hyperparathyroidism. Methods: The present cross-sectional descriptive-analytical study was performed on 17 healthy individuals and 17 patients who suffered from resorptive hypercalciuria in the dialysis center of Shahid Beheshti hospital in Babol in 2018. If patients had two or more decayed teeth, they were referred to a specialized maxillofacial clinic by the dentist for free panoramic imaging. Mandibular cortical index, LD, bone change, mandibular resorption (MR), and general cortical indices underwent examination. Results: The mean age of the control and case groups was 36.58±11.81 years and 40.23±14.32 years, respectively (P=0.424). In addition, the mean MI was 4.27±0.87 and 2.98±0.75 in the control and case groups, respectively (P<0.001). Based on the results, the mean gonion region’s cortical bone thickness was 0.93±0.23 and 1.09±0.24 in the case and control groups, respectively (P<0.001). Further, bone changes (P=0.036) and MR (P=0.017) were significantly different in the case and control groups. However, LD vision showed no significant difference in the hyperparathyroidism and the control groups (P=0.141). Conclusion: The results demonstrated a decrease in the thickness of the cortical bone in the guinea pig, mental region, and lack of dental canal in resorptive hypercalciuria compared to healthy individuals.

Dynamic Torque Limitation vs Static Torque Limitation for Bone Screws in Pig Bone

Dynamic Torque Limitation vs Static Torque Limitation for Bone Screws in Pig Bone

Deep learning-based temperature prediction during rotary ultrasonic bone drilling

Bone drilling is a common but critical medical procedure in orthopedic surgeries used to treat fractured bones. During this procedure, the temperature of the bone increases due to generation of frictional energy. Temperature control has been a major challenge in bone drilling since its foundation. If this temperature increases over 47°C for 1 min, then it can result in permanent bone damage. To control the temperature elevation this study proposes a deep learning-based robust predictive model which has been trained and tested on data from pig bones. Excessive in-house testing has been done on pig femur bones to gather data and verify the results. Rotary ultrasonic bone drilling was the machining process used for drilling. Four independent variables which were rotational speed, feed rate, abrasive grit size, and vibrational ultrasonic power were varied and the temperature for each set of values was recorded. Multiple deep learning models were made and were compared on different error metrics. It was found that convolutional neural network 1D gave the least error over other models. The error generated by deep learning models was less than mathematical and experimental models.

442 Effects of added 25(OH)D3 with varying standardized total tract digestible phosphorus levels on nursery pig performance, bone and urine characteristics, and serum vitamin D

442 Effects of added 25(OH)D3 with varying standardized total tract digestible phosphorus levels on nursery pig performance, bone and urine characteristics, and serum vitamin D

Treatment of clay soil contaminated with lead by in-situ immobilization process using animal bones

In this work, the application of bone wastes –Cow Bone, Pig Bone, and Horse Bone for the treatment of Lead (Pb) in Clay Soil by in-situ immobilization process, was investigated. The bone wastes were carbonized at a temperature of 700 OC for five hours. The Cow Bone Ash (CBA), Pig Bone Ash (PBA), and Horse Bone Ash (HBA) obtained were characterized with X-Ray Fluorescence (XRF). The physicochemical analysis of the soil sample was also performed. Batch experiments were done to investigate the effects of amendment dosage, time, and pH on immobilization efficiency. The physicochemical characterization of the amendments showed that they contain principally calcium phosphate. The XRF revealed that CBA contains 49.25 % CaO and 42.406 % P2O5, PBA contains 46.6 % CaO and 40.488 % P2O5 and HBA contains 45.664 % CaO and 33.857 % P2O5. The batch immobilization experiment revealed that CBA performed better than other sorbents in the removal of Pb. The removal efficiency is in the order CBA > PBA > HBA. The maximum removal of Pb in 100 g of soil was 71.2 %. This investigation has shown that animal bones can successfully remediate lead by immobilization process in a Pb contaminated Clay soil.

Behavioral dynamics of medicinal signaling cells from porcine bone marrow in long-term culture.

Medicinal signaling cells (MSC) hold promise for regenerative medicine due to their ability to repair damaged tissues. However, their effectiveness can be affected by how long they are cultured in the lab. This study investigated how passage number influences key properties for regenerative medicine of pig bone marrow MSC. The medicinal signiling cells derived from pig bone marrow (BM-MSC) were cultured in D-MEM High Glucose supplemented with 15% foetal bovine serum until the 25th passage and assessed their growth, viability, ability to differentiate into different cell types (plasticity), and cell cycle activity. Our findings showed that while the cells remained viable until the 25th passage, their ability to grow and differentiate declined after the 5th passage. Additionally, cells in later passages spent more time in a resting phase, suggesting reduced activity. In conclusion, the number of passages is a critical factor for maintaining ideal MSC characteristics. From the 9th passage BM-MSC exhibit decline in proliferation, differentiation potential, and cell cycle activity. Given this, it is possible to suggest that the use of 5th passage cells is the most suitable for therapeutic applications.

Efficient cadmium-resistant plant growth-promoting bacteria loaded on pig bone biochar has higher efficiency in reducing cadmium phytoavailability and improving maize performance than on rice husk biochar

Green agriculture faced challenges due to the shortage of efficient cadmium (Cd)-resistant plant growth-promoting bacteria (CdR-PGPB) and their low survival rate and activity during application. In this study, a diverse range of efficient CdR-PGPB were isolated from the rhizosphere soil of Desmodium elegans, especially those with high phosphate-solubilizing capabilities (272.87–450.45 mg L−1). Two highly efficient CdR-PGPB namely, XH1 and XH3 were loaded on to rice husk biochar (RHB) and pig bone biochar (PBB), labelled as RHBM and PBBM respectively. This study aimed to explore their effectiveness and mechanisms in promoting maize growth in a Cd-contaminated planting system. Results showed that PBBM performed best among all treatments. It significantly decreased soil phytoavailable Cd by 53.19 % and Cd content in maize shoot by 85.89 %. It also increased soil available phosphorus by 145.72 %, soil alkaline phosphatase activity by 76.34 %, maize shoot/root biomass by 47.06 %/67.98 %, Chlorophyll (a/b) content by 66.80 %/134.13 % and peroxidase activity by 171.96 %. These results were achieved through the synergistic action of efficient CdR-PGPB and PBB. Therefore, PBBM proved to be a promising and innovative application technique for sustainable agricultural development in Cd-contaminated farmland ecosystems.

Development of fishbone powder and carbon-jute fiber reinforced unsaturated polyester based novel green composites: investigation of tensile, impact strength, and morphology microstructure

In the last decade, hybrid composites have been the subject of significant advancements and study. This fast expansion necessitated the development of lightweight composite material with enhanced mechanical strength. In the past few years, the utilization of organic wastes from the food industry, like powder from cow bone, pig bone, and fishbone, has substantially improved the mechanical characteristics of composite materials. Owing to the increasing growth of the meat-based fisheries industry, fish bones are readily available. These bones are often thrown, causing environmental damage. Hence, a sustainable and unique hybrid composite was created employing fish bone powder (FBP) as filler in carbon/jute fibers reinforced polyester matrix. The hybrid composite was compression-molded. FTIR, SEM, and EDS studies were used to characterize the composite. The ASTM standard was used as a reference to explore the mechanical strength (tensile and impact). Additionally explored are the effects of alkali treatment of jute fiber on the above-mentioned processes. It was revealed that the inclusion of FBP and alkali treatment enhanced the mechanical characteristics of the composite. Fishbone powder with a particle size range of 200–250 μm and a weight percentage of 10 to 15% had significant fiber attachment which resulted in improved strength. The produced green composites have proven to be a viable choice for bio-waste treatment in the food sector.

FIB-SEM Study of Archaeological Human Petrous Bones: 3D Structures and Diagenesis

The petrous bone generally preserves ancient DNA better than other fossil bones. One reason for this is that the inner layer of the petrous bone of pigs and humans contains about three times as many osteocytes as other bones, and hence more DNA. A FIB-SEM study of modern pig petrous bones showed that the 3D structure of the thin inner layer is typical of woven bone that forms in the fetus, whereas the thicker outer layer has a lamellar structure. The lamellar structure is common in mammalian bones. Here we study human petrous bones that are about 2500 years old, obtained from three Phoenician sites in Sicily, Italy. A detailed FIB-SEM study of two of these bones, one well preserved and the other poorly preserved, shows that the 3D bone type structure of the human petrous inner layer is woven bone, and the outer layer is lamellar bone. These are the same bone type structures found in pig petrous bones. Furthermore, by comparing nine differently preserved petrous bones from the same archaeological region and age, we show that their collagen contents vary widely, implying that organic material can be significantly altered during diagenesis. The mineral crystals are better preserved and hence less crystalline in the inner layers compared to the outer layers. We therefore infer that the best-preserved DNA in fossil petrous bones should be found in the thin inner layers immediately adjacent to the otic cavity where much more DNA is initially present and the mineral phase tends to be better preserved.

Unraveling the outstanding catalytic efficiency of unprocessed bone-derived biochar: A deep dive into the mechanisms of native organic encapsulation and defective nitrogen doping in boosting persulfate activation for tetracycline degradation

Designing efficient non-metallic catalysts for persulfate (PS) activation has attracted broad attention due to their demonstrated immense potential in environmental remediation. In this study, unprocessed pig bone waste was successfully converted into biochars (PBCs) through a straightforward one-step pyrolysis process, which function as efficient PS catalysts for the removal of tetracycline (TC). The results revealed that the endogenous inner layer hydroxyapatite activator (IHA) and the rich native outer layer organic component wrapped with nitrogen-doped additives (OONA) found in raw bone-derived waste biomass collaborate to exert a dual effect of template and surface modification at 900 °C. Notably, under this synergistic action, 900PBC exhibited active defect nitrogen (pyridinic and graphitic nitrogen), sp2-hybridized groups (C = C, C = O, and C = N) and high defect levels (ID/IG = 1.0291), along with a cross-linked micro-mesoporous structure. This unique combination of properties endowed 900PBC with excellent catalytic activity, enabling it to effectively remove 50 mg/L of TC in the PS system within 30 min, primarily through a dual reaction pathway involving oxygen-active species (O2·-, 1O2) and electron transfer (fitting instantaneous-current values to PS concentrations, R2 = 0.95). Density-functional theory calculations confirmed that, within the nitrogen configurations located at defect sites, pyridinic nitrogen exerted a significant influence on the electron cloud density of adjacent carbon networks, subsequently promoting the formation of excited states of PS. Meanwhile, graphitic nitrogen constructed electron bridges with adjacent sp2-hybridized orbitals, facilitating the formation of the metastable complex 900PBC-PS*. Remarkably, 900PBC also exhibited excellent cyclic stability, maintaining a 93 % TC removal rate after four cycles,as well as high tolerance to a broad pH range (3–9), high concentrations of coexisting ions (10 mM), and diverse real-world water bodies. This study offers novel insights into synthesizing high-value biochar from waste bones with high catalytic activity.

Mechanical Vibration - A quick and EfficienMethod of Removing Damaged Prosthesis from its Cemented Position

Implant replacement or revision surgery in thehuman body ranks among the most demanding surgeries that orthopedic surgeons encounter in modern medicine.The removal of the hardened bone cement which securesthe implant within the bone, is the cause of a lengthyoperation. Often the use of sharp surgical instruments,ultrasonic devices etc. are employed, however all thesemethods are time-consuming and present variouscomplications.This paper describes the use of mechanical vibrations at afrequency of 40 Hz, on samples of implants anchored inanimal (pig) bone cavities with bone cement. Using a rotaryhammer drill equipped with a specially designed adaptor, toengage the tip of the implant, good results were obtained.The implant with its cement mantle was removed in a shorttime not exceeding 22 seconds.The procedure appears to be safe and is accomplished ina short time, commensurate with what is required inrevision surgery.

Atoh1 overexpression promotes Guinea pig bone marrow mesenchymal stem cells to differentiate into neural stem cell

Sensorineural hearing loss (SNHL) is a prevalent condition in otolaryngology. A key obstacle is finding effective strategies for regenerating damaged cochlear hair cells in adult animals. A practical and reliable approach has been developed to create a superior cell source for stem cell transplantation in the inner ear to treat SNHL. Atoh1 is involved in the differentiation of neurons, intestinal secretory cells, and mechanoreceptors including auditory hair cells, and thus plays an important role in neurogenesis. Lentivirus-mediated transfection of bone marrow mesenchymal stem cells (BMSCs) was utilized to achieve stable expression of the essential transcription factor Atoh1, which is crucial for developing auditory hair cells without compromising cell survival. By manipulating the induction conditions through altering the cell growth environment using anti-adherent culture, the synergistic impact of basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) was effectively applied to significantly improve the differentiation efficiency of bone marrow-derived mesenchymal stem cells (BMSC) into neural stem cells (NSCs) following Atoh1 transfection, thereby reducing the induction time. The study indicated that the newly proposed transdifferentiation method effectively transformed BMSCs into NSCs in a controlled environment, presenting a potential approach for stem cell transplantation to promote hair cell regeneration.

Comparison of false starts by saw created on flesh and dry bones; as close as possible to the real conditions of criminal dismemberment.

In most experimental protocols, false starts are produced on dry bones obtained through a maceration process for anthropological analyses, for the sake of reproducibility. Although this allows for controlled experimental conditions, the absence of soft parts when experimentally creating false starts does not correspond to the real conditions of criminal dismemberment. The main objective of this study was to determine if the results of experimental work on the characteristics of false starts were valid under medico-legal conditions. In this experimental study, a hand saw (rip saw, wavy set, TPI 32) was used. 240 false starts were produced on human and pig bones. Randomly, the false starts were either produced on a dry bone or on a flesh bone. The criteria for microscopic analysis included the shape of the walls, the shape and visibility of striae on the floor, the shape of the profile, and the minimum width of the false start. On human bone, 100% of the false starts produced on a bone that had previously undergone a maceration process for anthropological analyses (dry bone) allowed the definition of all the blade characteristics. This was the case for 78.3% on bone in the presence of soft tissue (flesh bone). The striae on the floor of the false start are in some cases less visible with flesh bones, implying that it may be more difficult to conclude on the characteristics of a saw under medico-legal conditions.

43 Evaluating the effects of HiPhorius phytase added in diets at or below the P requirement on nursery pig growth performance and bone mineralization

Abstract A total of 297 pigs (DNA 241 × 600; initial body weight = 8.64 ± 0.181 kg) were used in a 21-d trial to evaluate the effects of HiPhorius phytase (dm-firmenich, Parsippany, NJ) on pig growth performance and bone mineralization. All pigs were fed P depletion diets (0.09% aP) for a 3-d period before the start of the study (d 14 after weaning). Pens of pigs were then assigned to 1 of 5 treatments in a randomized complete block design with 5 pigs per pen and 12 replications per treatment. The first three diets were formulated to contain 0.09% aP; without added phytase (control), or control with 600 or 1,000 FYT/kg of added phytase (considering a release of 0.15 or 0.18% aP, respectively). The remaining two diets were formulated to contain 0.27% aP, one without added phytase and the other with 1,000 FYT/kg. One pig per pen was euthanized on d 21 and the right fibula, 10th rib, and metacarpal were collected to determine bone density, bone ash, and bone Ca and P. From d 0 to 21, increasing phytase in diets containing 0.09% aP increased (linear, P ≤ 0.002) average daily gain (ADG), average daily feed intake (ADFI), and gain to feed ratio (G:F) and increased percentage bone ash in metacarpals and 10th ribs (linear, P < 0.001; quadratic, P = 0.004, respectively), and increased grams of Ca and P in all three bones (linear, P ≤ 0.027; Table). Adding 1,000 FYT/kg in diets with 0.27% aP did not impact growth performance, but increased percentage bone ash (P ≤ 0.038) in all bones and grams of Ca and P in fibulas and 10th ribs (P ≤ 0.023) compared with pigs fed 0.27% aP without added phytase. Increasing aP from 0.09% to 0.27% in diets without added phytase increased (P < 0.001) ADG, ADFI, and G:F and increased bone density (P ≤ 0.002) in fibulas and metacarpals, percentage bone ash in all bones (P ≤ 0.074), and increased (P < 0.05) grams of Ca and P in fibulas and 10th ribs. Increasing aP from 0.09 to 0.27% aP in diets with 1,000 FYT added phytase increased bone density (P ≤ 0.008) in fibulas and metacarpals, percentage bone ash in all bones (P ≤ 0.002), and grams of Ca and P in fibulas and 10th ribs (P < 0.05). For growth performance (average of ADG and G:F), aP release was calculated to be 0.170% for 600 FYT/kg and 0.206% for 1,000 FYT/kg. For the average of all 3 bone measurements (average of 3 bones for bone density and percentage bone ash), aP release was calculated to be 0.120% and 0.125% for 600 and 1,000 FYT/kg, respectively.

PSI-16 Effect of HiPhorius phytase on finishing pig growth performance and bone mineralization with the use of two diet formulation strategies

Abstract Two experiments were conducted to determine the effect of HiPhorius (dsm-firmenich, Parsippany, NJ) phytase on finishing pig growth performance, serum chemistry, bone mineralization, and carcass characteristics. In Exp. 1, 1,161 pigs (PIC 337 × 1050, initially 36.7 ± 0.48 kg) were used in a 105-d trial. There were 27 pigs per pen and 10 or 11 replications per treatment. Treatments consisted of: 1) Control diet with no added phytase and formulated to NRC (2012) requirement estimates for standardized total tract digestible (STTD) P; 2) 600 FYT/kg added phytase formulated to the same STTD P as the control diet considering a release of 0.13% STTD P and 0.095% STTD Ca; 3) 1,000 FYT/kg added phytase formulated to the same STTD P as the control diet considering release of 0.16% STTD P and 0.107% STTD Ca, and 4) high STTD P (no phytase; approximately 22% above NRC requirement estimates). All diets were formulated to a 1.30:1 STTD Ca:STTD P ratio, but analysis suggested all phases were greater than the formulated target. Overall, pigs fed NRC (2012) or increased STTD P had increased average daily gain (ADG) and hot carcass weight (HCW; P < 0.05) compared with pigs fed the treatments with added phytase. Pigs fed NRC (2012) STTD P had greater (P < 0.05) gain to feed ratio (G:F) compared with those with 1,000 FYT/kg with other treatments intermediate. In Exp. 2, 1,160 pigs (PIC 337 × 1050, initially 75.9 ± 1.32 kg) were used in a 58-d trial. There were 27 pigs per pen and 11 replications per treatment. Treatments were the same as in Exp.1 except diets were formulated to the same total Ca:P ratio [1.15:1 from 75 to 100 kg and 1.12:1 from 100 to 136 kg body weight (BW)] without a STTD Ca release consideration from phytase; however, diets analyzed with a wider Ca:P compared with the expected value (Table 1). Overall, there were no differences in ADG, average daily feed intake (ADFI) or G:F among treatments (P > 0.10). For pigs fed NRC or increased STTD P, there was an increase (P < 0.05) in metacarpal bone density, and a tendency for increased (P < 0.10) bone ash weight and percentage bone ash compared with pigs fed treatments containing phytase. In conclusion, regardless of diet formulation strategy, pigs fed diets with phytase had decreased growth performance (Exp.1) and bone mineralization (Exp.2), which was unexpected and could be a result of the nutrient release values attributed to the phytase being overestimated, not enough phytate-bound P that is phytase-sensitive present in the diets, or too wide of a Ca:P ratio leading to reduced phytase activity in the analyzed diet samples compared with the intended ratio based on diet formulation.