Barley, Triticale, or Rye? The Type of Grain Can Affect the Growth Performance and Meat Quality of Sustainable Raised Pigs.

The effect of high level of barley, triticale, or rye as base of complete mixtures for growing-finishing pigs on growth performance, carcass traits, meat quality, and fatty acid profile in meat and backfat was investigated. The 100-day experiment involved 72 pigs, assigned into three groups (24 animals each). Pigs of each group were kept in six pens (two gilts and two barrows per pen). Diets offered to pigs differed in the proportion of cereals as the leading ingredients in the mixture formulation: I-barley, II-triticale, III-rye. The results showed diversified grain influence on the production results and meat quality. Triticale- and barley-based diets ensured better weight gain and lower carcass fatness than rye (p ≤ 0.05). The basic nutrients digestibility of mixtures containing triticale was comparable to that containing barley and higher than that of rye (p ≤ 0.05). The meat and backfat of pigs receiving diet with triticale or barley was characterized by more favorable fatty acids profile in respect to the health-promoting indicators (atherogenicity and thrombogenicity indexes; hypocholesterolemic/hypercholesterolemic ratio). The cholesterol level in various tissues was the lowest in pigs fed with rye diet, and their meat characterized by better water holding capacity and more SFA. Higher fat saturation indicate better resistance to oxidation during storage and longer meat shelf life. It seems that the supplementation of triticale to diet may improve the growth efficiency of pigs and the health-promoting value of meat, while the supplementation of rye may be better for the production of traditional or long-matured meat products.

Influence of the Zinc and Fibre Addition in the Diet on Biomechanical Bone Properties in Weaned Piglets.

The effects of the zinc and fibre source in piglets' diet on the bone mineral content, density, and strength parameters of the femur were investigated using 24 piglets fed a diet supplemented with either lignocellulose (LC) or potato fibre (PF). Half of each group of piglets consumed a diet with ZnSO4 monohydrate or with zinc glycinate (ZnGly). The diets contained similar amounts of lysine, energy, and fibre. Bone mineral content and density were over 9% higher in pigs receiving diets with ZnGly than in animals fed diets with ZnSO4. Moreover, ZnGly strongly improved maximum and elastic strength (by 25.7 and 20.0%, respectively, p < 0.0001) and bone stiffness (by 29.4%, p < 0.0001). Only the mass of the femur was affected by the type of fibre in the diet, as the femurs of piglets fed diets with LC were over 7% (p < 0.0001) heavier than in piglets fed diets with PF. The intake of digestible zinc and the zinc content in the blood serum were positively correlated with the measured bone parameters and, depending on the parameter, "r" ranged from 0.749 to 0.866 and from 0.400 to 0.479, respectively. It can be concluded that bone parameters are affected more strongly by the organic than inorganic source of zinc.

The Synthesis and Evaluation of Aminocoumarin Peptidomimetics as Cytotoxic Agents on Model Bacterial E. coli Strains.

This work presents the successful synthesis of a library of novel peptidomimetics via Ugi multicomponent reaction. Most of these peptidomimetics contain differently substituted aminocoumarin; 7-amino-4-methylcoumarin and 7-amino-4-(trifluoromethyl) coumarin. Inspired by the biological properties of coumarin derivatives and peptidomimetics, we proposed the synthesis of coumarin incorporated peptidomimetics. We studied the potential of synthesized compounds as antimicrobial drugs on model E. coli bacterial strains (k12 and R2-R4). To highlight the importance of coumarin in antimicrobial resistance, we also synthesized the structurally similar peptidomimetics, using benzylamine. Preliminary cellular studies suggest that the compounds with coumarin derivatives have more potential as antimicrobial agents compared to the compounds without coumarin. We also analyzed the effect of aldehyde, free acid group and ester group on the course of their antimicrobial properties.

Effect of Inulin Source and a Probiotic Supplement in Pig Diets on Carcass Traits, Meat Quality and Fatty Acid Composition in Finishing Pigs.

In this experiment, we investigated the effect of the supplementation of probiotic bacteria in the diet with inulin or dried Jerusalem artichoke tubers on the performance, meat quality, and fatty acid composition in the meat and backfat of fatteners. One hundred and forty-four crossbred pigs (PIC × Penarlan P76) were divided into six groups and fattened from 30 to 114 kg. The meat proximate composition, pH, color, texture, shear force, water-holding capacity, sensory attributes, and thiobarbituric-acid-reactive substances were measured. Normal post-mortem meat glycolysis was demonstrated and no meat defects were present. The chemical constituents in muscle tissues were similar, except for intramuscular fat (IMF). The addition of the prebiotics resulted in a higher IMF level, whereas a significantly lower content was found after the probiotic supplementation. Meat from both prebiotic groups was lighter, less red, and more yellow and showed a higher hue angle. The addition of both prebiotics significantly improved the antioxidant status of meat (by approximately 16% and 18%) and the water-holding capacity (less free water and higher M/T ratios), but reduced shear force (by 17%, p ≤ 0.05) and hardness (by 39% and 35%, respectively, p ≤ 0.05). The addition of the prebiotics and probiotics had no effect on any of the evaluated sensory attributes.

Difference in Performance of EPI Pigs Fed Either Lipase-Predigested or Creon®-Supplemented Semielemental Diet.

Pancreatic enzyme replacement therapy (PERT) and fat predigestion are key in ensuring the optimal growth of patients with cystic fibrosis. Our study attempted to highlight differences between fat predigestion and conventional PERT on body composition of young pigs with exocrine pancreatic insufficiency (EPI). EPI and healthy pigs were fed with high-fat diet for six weeks. During the last two weeks of the study, all pigs received additional nocturnal alimentation with Peptamen AF (PAF) and were divided into three groups: H-healthy pigs receiving PAF; P-EPI pigs receiving PAF+PERT; and L-EPI pigs receiving PAF predigested with an immobilized microbial lipase. Additional nocturnal alimentation increased the body weight gain of EPI pigs with better efficacy in P pigs. Humerus length and area in pigs in groups L and P were lower than that observed in pigs in group H (p value 0.005-0.088). However, bone mineral density and strength were significantly higher in P and L as compared to that of H pigs (p value 0.0026-0.0739). The gut structure was improved in P pigs. The levels of neurospecific proteins measured in the brain were mainly affected in P and less in L pigs as compared to H pigs. The beneficial effects of the nocturnal feeding with the semielemental diet in the prevention of EPI pigs' growth/development retardation are differently modified by PERT or fat predigestion in terms of growth, bone properties, neurospecific protein distribution, and gut structure.

δ-Lactones-A New Class of Compounds That Are Toxic to E. coli K12 and R2-R4 Strains.

Lactones are among the well-known organic substances with a specific taste and smell. They are characterized by antibacterial, antiviral, anti-inflammatory, and anti-cancer properties. In recent years, among this group of compounds, new biologically active substances have been searched by modifying the main (leading) structure with new analogs with stronger or different responses that may have a toxic effect on the cells of pathogenic bacteria and constitute an alternative to commonly used antibiotics. A preliminary study of δ-lactone derivatives as new potential candidates for antibacterial drugs was conducted. Particular emphasis was placed on the selection of the structure of lactones with the highest biological activity, especially those with fluorine in their structure as a substituent in terms of action on bacterial lipopolysaccharide (LPS) in the model strains of Escherichia coli K12 (without LPS in its structure) and R2-R4 (LPS of different lengths in its structure). In the presented studies, on the basis of the conducted MIC and MBC tests, it was shown that the antibacterial (toxic) activity of lactones depends on their structure and the length of the bacterial LPS in the membrane of specific strains. Moreover, oxidative damage of bacterial DNA isolated from bacteria after modification with newly synthesized compounds after application of the repair enzyme Fpg glycosylase was analyzed. The analyzed damage values were compared with the modification with appropriate antibiotics: ciprofloxacin, bleomycin, and cloxacillin. The presented research clearly shows that lactone derivatives can be potential candidates as substitutes for drugs, e.g., the analyzed antibiotics. Their chemical and biological activity is related to coumarin derivatives and the corresponding δ-lactone groups in the structure of the substituent. The observed results are of particular importance in the case of increasing bacterial resistance to various drugs and antibiotics, especially in nosocomial infections and neoplasms, and in the era of a microbial pandemic.

1,2-Diarylethanols-A New Class of Compounds That Are Toxic to E. coli K12, R2-R4 Strains.

An initial study of 1,2-diarylethanols derivatives as new potential antibacterial drugs candidates was conducted. Particular emphasis was placed on the selection of the structure of 1,2-diarylethanols with the highest biological activity of lipopolysaccharides (LPS) in the model strains of Escherichia coli K12 (without LPS in its structure) and R2-R4 (with different lengths of LPS in its structure). In the presented studies, based on the conducted minimum inhibitory concentration (MIC) and MBC tests, it was demonstrated that the antibacterial (toxic) effect of 1,2-diarylethanols depends on their structure and the length of LPS bacteria in the membrane of specific strains. Moreover, the oxidative damage of bacterial DNA isolated from bacteria after modification with newly synthesized compounds after application of the repair enzyme Fpg glycosylases was analysed. The analysed damage values were compared with modification with appropriate antibiotics; bacterial DNA after the use of kanamycin, streptomycin, ciprofloxacin, bleomycin and cloxicillin. The presented research clearly shows that 1,2-diarylethanol derivatives can be used as potential candidates for substitutes for new drugs, e.g., the analysed antibiotics. Their chemical and biological activity is related to two aromatic groups and the corresponding chemical groups in the structure of the substituent. The observed results are particularly important in the case of increasing bacterial resistance to various drugs and antibiotics, especially in nosocomial infections and neoplasms, and in the era of pandemics caused by microorganisms.

All That Glitters Is Not Silver-A New Look at Microbiological and Medical Applications of Silver Nanoparticles.

Silver and its nanoparticles (AgNPs) have different faces, providing different applications. In recent years, the number of positive nanosilver applications has increased substantially. It has been proven that AgNPs inhibit the growth and survival of bacteria, including human and animal pathogens, as well as fungi, protozoa and arthropods. Silver nanoparticles are known from their antiviral and anti-cancer properties; however, they are also very popular in medical and pharmaceutical nanoengineering as carriers for precise delivery of therapeutic compounds, in the diagnostics of different diseases and in optics and chemistry, where they act as sensors, conductors and substrates for various syntheses. The activity of AgNPs has not been fully discovered; therefore, we need interdisciplinary research to fulfil this knowledge. New forms of products with silver will certainly find application in the future treatment of many complicated and difficult to treat diseases. There is still a lack of appropriate and precise legal condition regarding the circulation of nanomaterials and the rules governing their safety use. The relatively low toxicity, relative biocompatibility and selectivity of nanoparticle interaction combined with the unusual biological properties allow their use in animal production as well as in bioengineering and medicine. Despite a quite big knowledge on this topic, there is still a need to organize the data on AgNPs in relation to specific microorganisms such as bacteria, viruses or fungi. We decided to put this knowledge together and try to show positive and negative effects on prokaryotic and eukaryotic cells.

Effects of Fish Oil and Dietary Antioxidant Supplementation on Bone Health of Growing Lambs.

The aim of the present study was to assess the effects of partial replacement of rapeseed oil (RO) with fish oil (FO) combined with dietary supplementation of various antioxidants on the characteristics of lamb femur. Thirty male lambs were assigned to five dietary treatments and fed isoproteinous and isoenergetic diets for 35 days. The control diet was enriched with 3.0% RO, while the experimental diets were enriched either only with 2.0% RO and 1.0% FO or additionally with 0.1% carnosic acid, 0.1% carnosic acid and 0.35 ppm Se as selenized yeast, or 0.1% carnosic acid and 0.35 ppm Se as sodium selenite. After 35 days, the lambs were slaughtered, and the femur was dissected from the carcass of each animal and analyzed for morphometric, geometric, densitometric, and biomechanical properties. The dietary modifications, specifically the supplementation of FO and selenized yeast, significantly improved the geometric, densitometric, and biomechanical properties of lamb femur.

Effects of Viscosupplementation on Quality of Knee Joint Arthrokinematic Motion Analyzed by Vibroarthrography.

OBJECTIVE: To evaluate the influence of viscosupplementation on osteoarthritic knee arthrokinematics analyzed by VAG. It is considered that intra-articular hyaluronic acid injection may improve the function of synovial joints by recovery of friction-reducing properties of articular environment. DESIGN: Thirty-five patients with knee osteoarthritis (grade II according to the Kellgren-Lawrence system) and 50 asymptomatic subjects were enrolled in the study. Patients were analyzed at 3 time points: 1 day before and 2 weeks and 4 weeks after single injection of 1.5% cross-linked hyaluronate. Control subjects were tested once. The vibroarthrographic signals were collected during knee flexion/extension motion using an accelerator and described by variation of mean square (VMS), mean range (R5), and power spectral density for frequency of 50 to 250 Hz (P1), and 250 to 450 Hz (P2). RESULTS: Patients before viscosupplementation were characterized by about 2-fold higher values of vibroarthrographic parameters than controls. Two weeks after the procedure, the values of R5, P1, and P2 significantly decreased, in comparison to pre-injection. At 4 weeks post-injection, we noted a significant increase in R5, P1, and P2 values, when compared to 2 weeks post-injection. Finally, at 4 weeks post-injection, the level of VMS, R5, and P2 parameters did not differ from values obtained at pre-injection. CONCLUSIONS: We showed that viscosupplementation may be effective in providing arthrokinematics improvement, but with a relatively short period of duration. This phenomenon is observed as decreased vibroacoustic emission, which reflects a more smooth movement in the joint.

Effects of Immobilization and Re-Mobilization on Knee Joint Arthrokinematic Motion Quality.

BACKGROUND: Knee immobilization is a common intervention for patients with traumatic injuries. However, it usually leads to biomechanical/morphological disturbances of articular tissues. These changes may contribute to declining kinetic friction-related quality of arthrokinematics; however, this phenomenon has not been analyzed in vivo and remains unrecognized. Thus, the aim of the present study is to investigate the effect of immobilization and subsequent re-mobilization on the quality of arthrokinematics within the patellofemoral joint, analyzed by vibroarthrography (VAG). METHODS: Thirty-four patients after 6-weeks of knee immobilization and 37 controls were analyzed. The (VAG) signals were collected during knee flexion/extension using an accelerometer. Patients were tested on the first and last day of the 2-week rehabilitation program. RESULTS: Immobilized knees were characterized by significantly higher values of all VAG parameters when compared to controls (p < 0.001) on the first day. After 2 weeks, the participants in the rehabilitation program that had immobilized knees showed significant improvement in all measurements compared to the baseline condition, p < 0.05. However, patients did not return to normal VAG parameters compared to controls. CONCLUSION: Immobilization-related changes within the knee cause impairments of arthrokinematic function reflected in VAG signal patterns. The alterations in joint motion after 6 weeks of immobilization may be partially reversible; however, the 2-week physiotherapy program is not sufficient for full recovery.

Dietary n-3 PUFA content as a modulator of the femur properties in growing pigs.

The relationships between both dietary and empty body fatty acid composition and the morphometry, densitometry, geometry and biomechanical properties of the femur of growing pigs were analysed. A total of thirty-two pigs aged 115 d were divided into four groups (n 8 per group). The pigs were fed either a control diet (group C) or a diet supplemented with linseed oil (rich in α-linolenic acid (C18 : 3n-3), group L), fish oil (rich in EPA (C20 : 5n-3) and DHA (C22 : 6n-3), group F) and beef tallow (rich in SFA, group T). The diets differed in n-3 PUFA contents (0·63-18·52 g/kg) and n-6:n-3 PUFA ratios (0·91-14·51). At 165 d of age, the pigs were slaughtered and the fatty acids in the empty body were determined. Moreover, the left femur was dissected. The cortical wall thickness, cross-sectional area, cortical index, bone mineral content, bone mineral density, maximum elastic strength and maximum strength were lower (P<0·05) in the femurs of pigs from groups C and T than in those from groups F and L. Significant positive correlations were found between the densitometry, geometry and biomechanical properties of the femur and both dietary and empty body n-3 PUFA content, whereas significant negative correlations were observed between the same properties and both dietary and empty body n-6:n-3 PUFA ratio. The results of the present study suggest that in growing pigs α-linolenic acid has a similar positive effect on bone health to that of EPA and DHA.

The effect of inulin supply to high-fat diet rich in saturated fatty acids on pork quality and profile of sarcoplasmic protein in meat exudate.

The aim of the study was to evaluate the influence of inulin supply to high-fat diet rich in saturated fatty acids (SFA) on pork quality and profile of sarcoplasmic protein in drip loss. At 50 days of age, twenty cross-bred pigs (gilts) were randomly allotted to four groups: the control (C) group fed a standard diet, and three experimental (D1, D2 and D3) groups fed a high-fat diet rich in SFA. Moreover, pigs from the groups D2 and D3 consumed an extra inulin supply (7% of daily feed intake) from 85 to 120 days of age (for 5 weeks) and from 50 to 120 days of age (for 10 weeks) respectively. The addition of inulin to the diet reduced meaty odour and flavour significantly, improved tenderness and overall sensory quality of pork and additionally influenced ultimate pH, L* colour parameter, lactate level and protein content in meat. The diets also affected the profile of sarcoplasmic proteins. Significant effects were observed for the following enzymes-PK/PGI (pyruvate kinase/phosphoglucose isomerase) and ALD (aldolase), which are related to the intensity of post-mortem glycolysis. Presented data indicate that long-term inulin supply to high-fat diet has a positive effect on technological and sensory quality as well as protein profile of pork.

Bone mineralisation, mechanical properties and body phosphorus content in growing gilts as affected by protein or feed intake during depletion-repletion periods.

The influence of feed or protein depletion-repletion on phosphorus balance, and bone characteristics was studied on 70 growing pigs from 90 to 168 d of age. During depletion period (90-118 d of age), C pigs were fed semi ad libitum (95% ad libitum intake) on control diet; FR pigs (feed-restricted group) consumed 40% less of control diet compared to C pigs; PR pigs (protein-restricted group) were fed semi ad libitum a low-protein diet containing 40% less protein than control diet. During repletion period (119-168 d of age), daily allowances for C pigs were equal of 95% ad libitum intake. Remaining pigs consumed a control diet at the same amount as C pigs. Pigs were slaughtered at 90 d of age ("zero" animals, n = 7), following seven animals from each group at d 118, 146 and 168  of age. At 118 d of age, phosphorus content in the body was lower (p < 0.001) in FR than C and PR pigs. Lower phosphorus deposition and utilisation was observed in FR animals. Humerus in FR pigs was lighter, had lower mineral content and density, but had greater stiffness than in PR and C pigs. During repletion period, FR pigs deposited more phosphorus and had better phosphorus utilisation than C and PR pigs. Humerus mineral density was greater in FR and PR than in C pigs. Humerus strength was the highest in PR pigs, and the lowest in FR pigs. Humerus stiffness was greater in PR than in C and FR pigs. In conclusion, during depletion period feed restriction affects bone growth more than protein restriction, and bone strength is less sensitive, than other bone characteristics, to feed restriction. Reductions in measured bone indices observed after lower feed intake can be fully compensated during the repletion period and resulted mainly from better utilisation of minerals.

Gait and functional status analysis before and after total knee arthroplasty.

BACKGROUND: Among the procedures for severe gonarthrosis, total knee arthroplasty (TKA) is considered a successful method patient satisfaction and functional improvement; however, TKA is commonly associated with incompletely recovered gait function. The aim of this study was to evaluate the influence of TKA and physiotherapy programmes on gait features and patient-reported functional status and the relationship between them, leading to broader knowledge of the origins of long-term gait disturbances. METHODS: Walking speed, step length and single support time were analysed by GAITRite system in 60 healthy controls and 21 TKA patients analysed at four time points: one day before and five days after surgery and before and after a three-week rehabilitation (12 and 15 weeks after surgery). Functional status was assessed using the Western Ontario and McMaster Osteoarthritis Index (WOMAC). RESULTS: At all time points, the TKA subjects walked significantly slower than the controls, but walking speed continuously increased after surgery. Gait asymmetries were observed in single support time (before surgery) and step length (after surgery). Partial restoration of gait function was observed 12 weeks after surgery and completion of the rehabilitation programme. An indirect correlation between gait velocity and function WOMAC subscores was found. CONCLUSIONS: Patients after TKA were characterised by significant improvements in self-reported functionality and progressive reduction of gait abnormalities, probably related to pain reduction. However, at 15 weeks after surgery, patients exhibited step length asymmetry, which could be considered as an effect of habits of three-point crutch gait in the early postoperative period.

Inulin supplementation reduces the negative effect of a high-fat diet rich in SFA on bone health of growing pigs.

Consumption of a high-fat diet, rich in SFA, causes deterioration of bone properties. Some studies suggest that feeding inulin to animals may increase mineral absorption and positively affect bone quality; however, these studies have been carried out only on rodents fed a standard diet. The primary objective of this study was to determine the effect of inulin on bone health of pigs (using it as an animal model for humans) fed a high-fat diet rich in SFA, having an unbalanced ratio of lysine:metabolisable energy. It was hypothesised that inulin reduces the negative effects of such a diet on bone health. At 50 d of age, twenty-one pigs were randomly allotted to three groups: the control (C) group fed a standard diet, and two experimental (T and TI) groups fed a high-fat diet rich in SFA. Moreover, TI pigs consumed an extra inulin supply (7 % of daily feed intake). After 10 weeks, whole-body bone mineral content (P=0·0054) and bone mineral density (P=0·0322) were higher in pigs of groups TI and C compared with those of group T. Femur bone mineral density was highest in pigs in group C, lower in group TI and lowest in group T (P=0·001). Femurs of pigs in groups TI and C had similar, but higher, maximum strength compared with femurs of pigs in group T (P=0·0082). In conclusion, consumption of a high-fat diet rich in SFA adversely affected bone health, but inulin supplementation in such a diet diminishes this negative effect.

Effects of Viscosupplementation on Knee Joint Arthrokinematics - Pilot Study.

BACKGROUND: Osteoarthritis is one of the most common dysfunctions of the musculoskeletal system and viscosup-plementation is becoming an increasingly popular treatment in OA. However, current knowledge regarding biomechanical changes in synovial joints reveals many discrepancies. Therefore, the aim of our study was to evaluate the effect of visco-supplementation on knee joint arthrokinematics as analyzed by vibroarthrography. MATERIAL AND METHODS: Seventeen individuals diagnosed with moderate knee osteoarthritis (VSC) were examined before and after a single injection of hyaluronate. A control group consisted of 30 asymptomatic individuals. During alter-nating extension/flexion of the knee joint, a 6-second vibroarthrographic signal was recorded using an accelerometer. The following parameters were calculated: variance (VMS), amplitude (R4), and spectral power density in the 50-250 Hz (P1) and 250-450 Hz (P2) bands. RESULTS: Statistical analysis showed significant differences (p<0.05) in the values of R4 and P2, which were higher in the VSC group than among the controls. After viscosupplementation, the values of R4, P1 and P2 in the VSC group de-creased to a level not significantly different from that seen among the controls. CONCLUSIONS: 1. After a single intra-articular HA injection, joint motion-related vibrations were reduced, which was recorded as a decreased intensity of vibroacoustic emission. 2. This suggests that the use of viscosupplementation in pa-tients with moderate knee osteoarthritis may improve qualitative aspects of arthrokinematics.

Effects of dietary fat on the saturated and monounsaturated fatty acid metabolism in growing pigs.

The effect of dietary fats differing in fatty acid (FA) composition on the metabolism of saturated FA (SFA) and monounsaturated FA (MUFA) in growing pigs was investigated. The deposition of FA in the body and the fate of individual dietary FA were assessed after slaughter. Gilts with an initial body weight (BW) of 60 kg were used as experimental animals. Six pigs were slaughtered at 60 kg BW, while further 18 pigs received three isoenergetic and isonitrogen experimental diets containing linseed oil, rapeseed oil or beef tallow at 50 g/kg diet until they reached 105 kg (six pigs per group). The chemical composition and the content of FA in the whole body were determined and compared across groups. Regardless of dietary treatment, the whole body contained similar amounts of protein, fat and total FA. The total accumulation (percentage of net intake and de novo production) of SFA and MUFA was similar in all groups, but the processes of elongation and desaturation of SFA and MUFA depended upon the type of FA added to the diet. A high dietary content and intake of MUFA inhibits desaturation compared to SFA- and PUFA-rich diets, whereas a high SFA content and intake lowers elongation rate. The increasing net intake of total SFA and MUFA was associated with a lower total de novo production of these FA in the whole body of pigs.

Femur morphometry, densitometry, geometry and mechanical properties in young pigs fed a diet free of inorganic phosphorus and supplemented with phytase.

The study investigated in piglets the effect of replacing dietary inorganic P by addition of microbial phytase and its impact on performance, nutrient digestibility and on the geometrical characteristics and mineralisation of the femur. Sixteen pigs on day 58 of age were divided into two groups and fed either a diet free of additional inorganic phosphorus (P) and supplemented with phytase (Diet LP, 4.23 g total P/kg diet) or a diet with a mineral source of P and not supplemented with phytase (Diet SP, 5.38 g total P/kg diet). Performance data and the apparent total tract digestibility of nutrients were estimated between days 58 and 114, and 72 and 86 of age, respectively. On day 114 of age, the pigs were slaughtered, the femur was dissected and the mineral content and mineral density, maximum strength and maximum elastic strength, cortical wall thickness, cross-sectional area and cortical index were analysed. The growth performance and digestibility of nutrient fractions (with exception of P) did not differ between treatment groups. The P-digestibility was significantly higher in Group LP. The femur of pigs in Group LP had significantly greater cortical wall thickness, cortical index, bone mineral content, bone mineral density, maximum strength and maximum elastic strength than Group SP. Femur maximum strength and maximum elastic strength were correlated with cortical wall thickness and cortical index. Resulting from the different supply of digestible P, the femur geometrical, densitometric and mechanical properties of Group LP were better than those of Group SP. The mechanical properties of the femur of pigs depended more on its geometrical characteristics than on the degree of its mineralisation.

Bone mineralisation of weaned piglets fed a diet free of inorganic phosphorus and supplemented with phytase, as assessed by dual-energy X-ray absorptiometry.

Sixteen female piglets (58 d of age, 16.8 ± 0.8 kg body weight [BW]) were assigned to two groups (n = 8) and received until day 100 of age (50.3 ± 1.2 kg BW) ad libitum either a diet with a standard (diet C) or low (diet L) total phosphorus (P) content (5.38 and 4.23 g/kg, respectively). Diet C was supplemented with mineral P (1.15 g/kg) and did not contain microbial phytase. Diet L did not contain any inorganic P but 750 FTU/kg of microbial phytase. Despite these treatments, both diets were composed with the same ingredients. Body mineralisation of each gilt was assessed by determining the bone mineral content (BMC), area bone mineral density (BMD) by the dual-energy X-ray absorptiometry (DXA) at days 58, 72, 86 and 100 of age. Feeding diet L caused a higher P digestibility (p = 0.008) measured from days 72 to 86 of age and at 100 days of age a higher BMC and BMD (p ≤ 0.01). Furthermore, the gilts of group L deposited more minerals in the body than control pigs (by 2.4 g/d, p = 0.008). It was found that BMD and BMC were positively correlated with body lean mass and digestible P intake. The results indicated that, even for very young pigs, the addition of microbial phytase instead of inorganic P increases the amount of digestible P covering the requirements of piglets for proper bone mineralisation. Furthermore, it was proved that the DXA method can be successfully applied to measure body fat and lean mass contents as well as bone mineralisation of growing pigs using the same animals.