Relative bioavailability of phosphorus in high-protein sunflower meal for broiler chickens and effects of dietary phytase supplementation on bone traits, growth performance, and apparent ileal digestibility of nutrients

An experiment was conducted to determine the relative bioavailability (RBV) of P in high-protein sunflower meal (HP-SFM) fed to broiler chickens based on bone traits and to determine the effects of dietary phytase supplementation and increasing levels of HP-SFM as a P source on bone traits, growth performance, and apparent ileal digestibility (AID) of DM and nutrients. In total, 240 broiler chicks were randomly allotted to 1 of 10 experimental diets with 6 replicate cages of 4 birds each and fed experimental diets from day 14 to 21 of age. Diets included a corn-soybean meal-based basal diet (0.35% total P; P-deficient diet), or the basal diet supplemented with 0.05, 0.10, or 0.15% P from either monosodium phosphate (MSP) or HP-SFM. Another 3 diets were formulated by supplementing the HP-SFM-containing diets with 500 phytase unit/kg of phytase. The bone mineral content (BMC), bone area (BA), and bone mineral density (BMD) of femur and tibia and tibia ash content increased (linear, P < 0.01) with increasing dietary P content from MSP. A linear increase in femur and tibia BMC, femur BA, and tibia BMD was also observed (P < 0.01) with increasing level of dietary P from HP-SFM. The RBV of P in HP-SFM based on femur and tibia BMC were 41 and 44%, respectively. Dietary phytase supplementation increased (P < 0.01) most of bone traits of the birds except for femur BMD. In addition, birds fed the diets supplemented with dietary phytase had greater (P < 0.05) BW gain, feed efficiency, and AID of P than those fed the diets without dietary phytase. In conclusion, the estimated RBV of P in HP-SFM to P in MSP were 41 and 44% based on femur and tibia BMC, respectively. Also, dietary phytase supplementation increased AID of P, growth performance, and bone traits of the birds fed P-deficient diets containing increasing inclusion level of HP-SFM as a P source.

Metabolizable energy and standardized ileal digestible amino acid contents of a high-protein sunflower meal fed to broiler chicks

This study was conducted to determine the standardized ileal digestible amino acid (AA) and nitrogen-corrected apparent metabolizable energy (AMEn) contents of a high-protein sunflower meal (HiSFM) fed to broiler chicks. A total of 144 broiler chicks were randomly allotted to one of three dietary treatments with eight replicate cages of six birds. Birds were fed the experimental diets from day 14 to day 21 of age. The results showed that gross energy, crude protein, nonphytate phosphorus, lysine (Lys), methionine (Met), threonine (Thr), and total nonstarch polysaccharide contents of HiSFM were 4178 kcal kg−1, 48.7%, 0.86%, 1.59%, 0.75%, 1.45%, and 14.6%, as-fed basis, respectively. The standardized ileal digestible Lys, Met, and Thr of HiSFM were 12.6, 6.8, and 11.6 g kg−1(dry matter basis), respectively. In addition, the AMEncontent of HiSFM fed to broiler chicks was 1785 kcal kg−1. In conclusion, compared with literature values for sunflower meal, HiSFM had lower standardized ileal digestibility of indispensable AA and higher AMEncontent. The standardized ileal digestible AA and AMEnvalues of HiSFM obtained from the current study could be used when formulating poultry diets and to obtain predictable bird performance.

Improvement of the nutritional value of high-protein sunflower meal for broiler chickens using multi-enzyme mixtures

Two experiments were conducted to determine the effect of replacing soybean meal (SBM) with a high-protein sunflower meal (HiSFM) without or with multi-enzyme mixtures on growth performance, nutrient utilization, jejunal digesta viscosity, and excreta moisture in broiler chickens. In experiment 1, 400 chicks were divided into 40 replicates of 10 birds and fed for 35 d a corn-soybean meal (CSBM) control diet or CSBM with 25 (HiSFM25), 50 (HiSFM50), 75 (HiSFM75), or 100% (HiSFM100) of total SBM replaced by HiSFM. During d 0 to 35, increasing HiSFM content in diets linearly reduced (P < 0.0001) BW, FI, and BW gain (BWG). Feeding HiSFM25 or HiSFM50 resulted in similar growth performance as CSBM (P > 0.05). In experiment 2, 120 chicks were divided into 24 replicates of 5 birds and fed CSBM or HiSFM75 diet without or with enzyme A (supplying 4,000, 500, and 8,000 U/kg of xylanase, alpha-amylase, and protease, respectively) or enzyme B (supplying 1,700, 1,100, 240, 30, 1,200, 360, 1,500, and 120 U/kg of cellulase, pectinase, mannanase, galactanase, xylanase, glucanase, amylase, and protease, respectively) for 21 days. Excreta moisture content was determined weekly, and birds were euthanized on d 22 to collect jejunal and ileal digesta for viscosity and apparent ileal digestibility (AID) measurements, respectively. Compared with CSBM, feeding HiSFM75 reduced (P < 0.05) BWG and G: F, enzymes A and D alleviated BWG and G: F reduction (P < 0.05), and enzyme A reduced (P = 0.037) the excreta moisture content, whereas the treatments did not influence AID or jejunal digesta viscosity measurements. In conclusion, experiment 1 results show that HiSFM can replace up to 50% of SBM without depressing growth performance in either the starter or finisher phase, whereas experiment 2 shows that enzymes A and B supplementation can alleviate the growth depression associated with feeding HiSFM75. These results suggest that enzyme supplementation can enhance HiSFM inclusion in broiler diets without affecting productivity or barn hygiene management.

Changing the omega-6 to omega-3 fatty acid ratio in sow diets alters serum, colostrum, and milk fatty acid profiles, but has minimal impact on reproductive performance

This experiment tested the hypothesis that reducing the omega-6 (n-6) to omega-3 (n-3) fatty acid (FA) ratio in sow diets will improve performance, characterized by increased litter size, decreased preweaning mortality, and improved growth performance. Second, we determined if the FA profile in sow and piglet blood, colostrum, and milk are altered when sows are fed diets with varied n-6:n-3 ratios and if the dietary FA ratio impacts circulating concentrations of IgG, IgA, eicosapentaenoic (EPA), or docosahexaenoic (DHA) acid. Sows (n=150) were assigned to 1 of 5 treatments (each divided into gestation and lactation diets) on d 80 of gestation. Period 1 (P1) is defined as d 80 of gestation to weaning and Period 2 (P2) refers to the subsequent breeding to weaning. Diets were wheat and barley based (5% crude fat) and treatments consisted of a control (tallow), 3 diets with plant oil-based n-6:n-3 ratios (9:1P, 5:1P, and 1:1P), and a 5:1 fish oil diet (5:1F). Litter size was unaffected by treatment during P1 and P2 (P>0.10). In P1, birth weight was unaffected by diet (P>0.10); however, weaning weight (P=0.019) and ADG from birth to weaning (P=0.011) were greatest for piglets born to 9:1P and 5:1P sows. During P2, 5:1F sows consumed 10% less feed during lactation (P=0.036), tended to have reduced piglet birth weights (P=0.052), and piglet weaning weight was reduced by 0.8 kg (P=0.040) relative to the other diets. Colostrum and piglet serum IgA and IgG concentrations were unaffected by diet (P>0.10). Serum n-3 FA were greatest in sows (P<0.01) consuming 1:1P and 5:1F diets and in their offspring (P=0.014). Serum α-linolenic acid (ALA) was greatest in 1:1P sows and EPA and DHA were greatest in 5:1F sows (P<0.01). In pre-suckle piglet serum, ALA did not differ among treatment groups (P>0.10). Relative to piglets of sows consuming the control diet, EPA was 2.5-fold greater in the 1:1P group and 4-fold greater in 5:1F group (P<0.01) before suckling. In post-suckle samples, ALA was greatest in piglets from the 1:1P sows (P<0.01) and EPA and DHA were greatest in piglets from the 5:1F sows (P<0.01). Feeding diets with plant-based n-6:n-3 ratios of 5:1 or 1:1 did not impact performance relative to a control group but improved the conversion of ALA into EPA and increased the transfer of n-3 to piglets through milk. When a fish-based 5:1 ratio diet was fed, pre-weaning mortality was increased, and piglet birth and weaning weights decreased.

Validation of the net energy content of canola meal and full-fat canola seeds in growing pigs

A study was conducted to estimate the net energy (NE) content of canola meal (CM) and full-fat canola seeds (FFCS) in growing pigs, and to validate the results through a growth trial. The digestible energy (DE) content of the canola products was measured in a digestibility study by the difference method, with diets containing two-thirds of a basal diet of known digestibility and one-third of the canola products. The NE content was estimated by means of a prediction equation based on the DE content and chemical composition of the canola products. The NE was 2.43 and 3.56 Mcal kg-1 DM for CM and FFCS, respectively. For the growth study, 31-kg pigs (18 per treatment) were fed for 35 d with wheat/barley-based diets containing either 0, 5, 10 or 15% FFCS or 0, 7.5, 15 or 22.5% CM. The gain-to-feed ratio was unchanged by the levels of CM or FFCS (P > 0.05), but the highest level of FFCS decreased feed intake (P < 0.001) and thus increased the gain-to-feed ratio (P < 0.05). In conclusion, the NE content was correctly estimated for CM, but slightly underestimated for FFCS. Also, growing pigs can tolerate diets containing up to 22.5% CM or 10% FFCS.Key words: Net energy, growing pigs, canola meal, full-fat canola seeds

Nutritional value of high-fat oat groats fed to weaned pigs

Oat groats with high-fat (HFOG) content for weaned pigs were evaluated. The HFOG contained 95 g fat, 159 g crude protein and 5.4 g of apparently digestible lysine per kilogram DM. Weaned pigs (8.5 kg) were fed diets containing 0, 150, 300 or 450 g HFOG kg-1 DM for 4 wk. No difference in overall average daily gain, feed intake or gain-to-feed ratio was observed between treatments. In conclusion, HFOG can replace a mixture of wheat, canola oil and soybean meal (84:7:9) in diets for nursery pigs. Key words: Weaned pig, oat groats, nutritional value, digestibility, growth

Determination of the digestible energy and prediction of the net energy content of toasted and non-toasted canola meals from Brassica junceae and Brassica napus in growing pigs by the total faecal collection and the indigestible marker method

The study aimed to compare the digestible and net energy (DE and NE) contents of three canola meals (CM) toasted (95°C) or not after desolventization from yellow Brassica junceae (YBJ) and yellow and black Brassica napus (YBN and BBN) in growing pigs. A basal diet and six CM-based diets (2/3 basal diet and 1/3 CM) supplemented with acid-insoluble ash (indigestible marker) were prepared. The growing pigs (28 kg; six per treatment) were kept in metabolic cages for 18 d and their faeces were collected for the last 10 d. The digestibilities and DE content of the CM were determined based on the total faecal excretion and the indigestible marker method. NE was estimated with a prediction equation. The DE and NE contents of the YBN meal (3.98 and 2.73 Mcal kg-1 DM) were higher (P = 0.007) than that of the YBJ (3.76 and 2.59 Mcal kg-1 DM) and BBN (3.64 and 2.43 Mcal kg-1 DM) meals. Toasting had no effect (P > 0.05) on the DE and NE contents. Inconsistent values were obtained with the indigestible marker, as compared with the total faecal collection method. In conclusion, YBN canola presents the highest energy content, and toasting of CM does not affect its energy values in growing pigs.Key words: Canola meal, growing pigs, toasting, digestible energy, net energy

Influence of source and concentrations of dietary fiber on in vivo nitrogen excretion pathways in pigs as reflected by in vitro fermentation and nitrogen incorporation by fecal bacteria

The inclusion of dietary fiber (DF) in diets has been suggested as a way to reduce NH(3) emission in pig barns because it contributes to a shift in N excretion from urine to feces owing to enhanced bacterial growth in the intestines. This study compared an in vitro method to measure bacterial protein synthesis during fermentation with an in vivo N excretion shift induced by diets differing in DF concentrations and solubility. The first experiment measured the effect of graded concentrations of sugar beet pulp (SBP; 0, 10, 20, and 30%) in corn- and soybean meal-based diets on in vivo N excretion partitioning between the urine and feces. A second experiment investigated the replacement of SBP, rich in soluble DF, with oat hulls (OH), rich in insoluble DF (20:0, 10.5:10.5, and 0:22%, respectively). In parallel, the fermentation characteristics of the dietary carbohydrates not digested in the small intestine were evaluated in an in vitro gas test, based on their incubation with colonic microbiota, using a mineral buffer solution enriched with (15)N. The N originating from the buffer solution incorporated into the bacterial proteins (BNI) was measured when half the final gas volume was produced (8.5 to 14.5 h of fermentation) and after 72 h of fermentation. Short-chain fatty acids were determined in the liquid phase. In the first experiment, the inclusion of SBP linearly decreased urinary N excretion from 0.285 to 0.215 g of N excreted in the urine per gram of N ingested and decreased the urinary-N:fecal-N excretion ratio from 2.171 to 1.177 (P < 0.01). In the second experiment, substituting SBP with OH linearly increased the urinary-N:fecal-N excretion ratio (P = 0.009). Unlike short-chain fatty acid production, BNI was greater at half-time to asymptotic gas production than at 72 h of fermentation. Sugar beet pulp enhanced BNI linearly (P < 0.001), 2.01, 2.06, and 2.35 mg g(-1) of diet with 10, 20, and 30% SBP, respectively, as compared with 1.51 mg for the control diet. The substitution of SBP with OH decreased BNI (P < 0.01). With the exception of final gas production, all in vitro kinetic characteristics and BNI were correlated with in vivo N excretion parameters, and regression equations for the prediction of N excretion pathways from in vitro data were identified. Even if the presence of resistant starch in the diet might alter the composition of the fibrous residue that is fermented, the in vitro method is a possible useful tool for the formulation of diets, reducing the effects of pig production on the environment.

Influence of carrier on the performance of dry powder inhalers

The aim of this work is to study carriers which can become alternatives to monohydrate lactose in dry powder inhalers and to consider particle parameters that influence adhesion between drug and carrier in dry powder inhalers. Different forms of mannitol, lactose and maltitol were mixed with either terbutaline sulphate or formoterol fumarate. The blends were submitted to different adhesion tests where drug detachment from the carrier was obtained either through mechanical vibration or by aspiration. Parameters like particle shape, roughness, amorphous content and cristalline form may affect interactions between drug and carrier. In our case, crystallized forms of the carrier offered lower adhesion but better release of the active ingredient than spray-dried forms. The crystallized mannitol produced maximal fine particle dose. The blends of the mannitols and the two active ingredients gave different results. The two techniques used to assess the adhesion of drugs to carrier particles provide complementary information about drug/carrier interactions and detachment. The mechanical sieving allows to assess blend stability and the air-jet sieving makes it possible to determine how easily the drug separates from carrier. For the drugs tested, the results of fine particle doses are in agreement with the Alpine air-jet sieve results. The tests used are helpful for the choice of a new carrier in the field of the development of new carriers for dry powder inhalers.

Nutritive value of tropical tree leaf meals in adult sows

Tree leaf meals (TLM) are increasingly used in the tropics to feed pigs. The nutritive value of the TLM of cocoyam (Xanthosoma saggitifolium), mulberry (Morus alba) and Trichanthera gigantea, their effect on the digestive tract and their fermentation rate in the large intestine, were determined in adult sows given diets containing 150 or 300 g TLM per kg. The TLM contained from 8·5 to 12·0 MJ digestible energy per kg dry matter (DM) and from 60 to 125 g digestible protein per kg DM. The digestibility was not affected ( P>0·05) by their rate of incorporation in the diet. The apparent ileal protein digestibility of the diets containing 300 g TLM per kg was also determined by the slaughtering method. It reached 80% for the basal diet and 54, 70 and 74% for the Trichanthera-, mulberry- and cocoyam-based diets, respectively. No diet effect ( P>0·05) was observed on the weight and length of the gastro-intestinal tract, with the exception of a heavier caecum in sows given the Trichanthera-based diet ( P<0·01). The pH of the gastric fluid of these sows was also higher ( P<0·001). The fermentation of the dietary fibre in the large intestine was evaluated by the gas technique using syringes. The cocoyam leaves presented the highest amount of total gas produced after fibre fermentation ( P<0·001). The ranking order of gas production was identical to that observed for the digestibility coefficients: Trichanthera <mulberry <cocoyam. In conclusion, TLM can represent up to 0·3 of a diet for sows. Their use in sow nutrition may be considered in tropical regions where protein sources are scarce.

Aerosolization potential of cyclodextrins--influence of the operating conditions

The aim of this work is to characterize the aerosols obtained by jet nebulization with cyclodextrin solutions and to study the influence of operating conditions on nebulization efficiency. Two cyclodextrins, an hydroxypropyl cyclodextrin (Kleptose HP) and a polydisperse methyl beta cyclodextrin (Crysmeb), were tested with 14 nebulizers that differ geometrically. We first determined the physicochemical properties of density, viscosity, and surface tension for the cyclodextrin solutions. Nebulization efficiency was evaluated by measuring droplet size, nebulization rate, quantity of solution nebulized, and nebulization time. We studied the influence of the technological parameters of pressure and nebulizer type and the influence of the formulation on performance efficiency. The use of different nebulizers and different pressure conditions results in variable efficiency. Regardless of the type of nebulizer, an increase in pressure decreases droplet size and increases nebulization rate. The influence of the nebulizer design is considerable. The aqueous cyclodextrin solutions studied can generate aerosols in particle size ranges suitable for pulmonary deposition. Large quantities of aerosol can be nebulized in acceptable nebulization times. The cyclodextrin concentration does not modify nebulization efficiency in the range tested.

Controlled drug release from Gelucire-based matrix pellets: Experiment and theory

The aim of this work was to elucidate the underlying drug release mechanisms from lipidic matrix pellets, using theophylline and Gelucire 50/02 as model drug and carrier material, respectively. Pellets were prepared by two different techniques: melt-solidification and extrusion-spheronization. The effects of different formulations and processing parameters on the resulting drug release kinetics in 0.1N HCl and phosphate buffer pH 7.4 were studied and the obtained results analyzed using adequate mathematical models in order to get further insight into the underlying mass transport mechanisms. The type of preparation technique was found to strongly affect the underlying drug release mechanisms. Drug release from pellets prepared by the melt-solidification method was primarily controlled by pure diffusion, whereas drug release from pellets prepared by the extrusion-spheronization method was purely diffusion-controlled only at early time points. After approximately 2h, the pellets started to disintegrate, resulting in decreased diffusion pathway lengths and, thus, increased drug release rates. Furthermore, the curing conditions significantly affected the theophylline release kinetics, whereas varying the initial drug loading from 20 to 50% (w/w) resulted only in a slight increase in the relative drug release rate. Interestingly, the effects of the size of pellets prepared by the melt-solidification method on the resulting drug release kinetics could be quantitatively predicted using an analytical solution of Fick's second law of diffusion. These predictions could be verified by independent experiments.

Influence of granulation and compaction on the particle size of ibuprofen--development of a size analysis method

The aim of this work was to study the impact of the process on drug particle size. We chose ibuprofen, practically insoluble in water, as granulometry greatly influences its dissolution rate. We developed an original method using a laser granulometer to assess the size of ibuprofen within a blend before and after granulation and then compression. Wet granulation was performed with a Lodige and a Diosna granulator. The granules were then compressed. The evolution of ibuprofen particle size after these operations was checked. Two grades of ibuprofen differing in size were studied: ibuprofen 25 and ibuprofen 50. After the wet granulation of ibuprofen 50 with a Lodige or a Diosna granulator, a decrease in size was observed. This could be caused by shocks occurring in the granulator. On the other hand, after compression of the granules, ibuprofen particle size increased and was greater than that measured before granulation. Compression could induce some fragmentation of ibuprofen associated with the plastic deformation and then, under pressure, a closeness of the fragments or deformed particles which could bind or associate with one another because the melting point of ibuprofen is not very high. In the case of ibuprofen 25, the same phenomena were observed after compression. But, after granulation, particle size was not modified. There was little breaking of ibuprofen particles in the granulator because they are much smaller than those of ibuprofen 50. This work shows the impact of the process on drug particle size when producing tablets. The method developed made it possible to differentiate and measure the size of ibuprofen particles in a blend.

A survey of pig production systems in the rain forest of the Pacific coast Colombia

A questionnaire-based survey was conducted in small-scale pig farms in the rain forest of the Colombian Pacific coast in order to study aspects of reproduction, nutrition and productivity. A total of 124 farmers was interviewed. They owned, on average, 13.6 pigs, including 2.3 sows, mainly of the Zungo breed. Pigs are reared in extensive systems and are allowed to wander freely in search of food. The sows produce, on average, 9.6 piglets/litter but, owing to poor sanitary conditions, 1.5 are born dead and only 6.3 are weaned alive. Two-thirds of the sows have five litters or more and the boars are also kept for a long time. This leads to high consanguinity rates within the herd and low productivity. Diets are based on maize, banana, tubers (taro, cassava) and fruits (peach palm, among others), and are rich in energy but poor in protein and minerals. The lack of protein and mineral sources appears to be the main limiting factor of these extensive production systems. Tree forages could partially solve the problem but are used by only 2% of the farmers. It is concluded that decreasing inbreeding, better piglet management and provision of balanced diets are areas that require immediate improvement.

Influence of the morphogranulometry and hydrophobicity of talc on its antisticking power in the production of tablets

Antisticking power varies according to the talc considered. It is difficult to define the physical properties of talc implicated in its antisticking power. In this work, different talcs were characterized and an evaluation made of their performance in reducing sticking in tablet manufacturing. Determination of the specific surface area was made by permeametry, morphogranulometric analysis by laser diffractometry using a method, which made it possible to assess the mean thickness of talc particles, and measurement of water absorption kinetics was taken to assess hydrophobicity. The relationship between the characteristics of talcs and their antisticking power was then considered. There is a correlation between the particle size of talc and surface hydrophobicity. The detaching force of tablets appears to be dependent on the basal dimension of talc.

Cyclodextrins as a potential carrier in drug nebulization

The inhalation route is widely studied for many drug applications focusing on either local or systemic distributions. One matter of concern is the solubilization of hydrophobic drugs. We have studied the feasibility of using different cyclodextrins (CDs) to elaborate pharmaceutical formulations for the inhalation route and tested the short-term toxicity of such formulations administered by inhalation to C57BL/6 mice. We have shown that HP-beta-CD, gamma-CD, as well as RAMEB aqueous solutions can undergo aerosolization and that the resulting droplet-size ranges are compatible with pulmonary deposition. In vivo, we have demonstrated that short-term exposure to inhaled HP-beta-CD, gamma-CD and RAMEB solutions are non-toxic after assessing bronchoalveolar lavage (BAL), lung and kidney histology, bronchial responsiveness to methacholine and blood urea. The only change noted is a slight increase in lymphocyte count in the BAL after HP-beta-CD and gamma-CD inhalation. We conclude that CDs are useful in significantly enhancing the solubility of apolar drugs with a view to inhalation therapy although an increase in lymphocyte counts in the BAL after CDs inhalations needs further investigations.

Development of 400 µm Pellets by Extrusion‐Spheronization Application with Gelucire 50/02 to Produce a “Sprinkle” Form

The aim of this study was to develop monodimensional, spherical particles of 400 microm by extrusion-spheronization. An Alexanderwerk GA65 cylinder extruder with two counter-rotating rollers associated with a Caleva model 15 spheronizer were used. The study was made with an auxiliary substance of fatty consistency and with amphiphilic properties: Gelucire 50/02. The plasticity of the mass can be deduced using a piston extruder. Pellet quality can be determined by particle-size analysis and shape estimation by microscopy. Modifications to the cylinders and the extruder itself are required for feasibility studies of extruded materials of 400 microm. The horizontal plate of the spheronizer had to be adapted to take into account the small size of the extruded materials. For the chosen auxiliary substance, Gelucire 50/02, the formulation of the wet mass to be extruded and the conditions required to obtain this mass were defined. The results show the feasibility of 400 microm pellets with Gelucire 50/02. At least 90% of the pellets have a particle size of between 250 microm and 500 microm and particle shape is acceptable. In this form the dose can be adapted to individual patients. After proving the feasibility of 400 microm spheroids of Gelucire 50/02, the association of a drug with it was considered.

Relation between structural characteristics of talc and its properties as an antisticking agent in the production of tablets

Antisticking power varies according to the talc considered. Besides its chemical properties, it is necessary to assess its physical properties related to functionality. It is difficult to define the physical properties of talc implicated in its antisticking power. In this work, different talcs were characterised and their performance in reducing sticking in tablet manufacturing was evaluated. The following parameters were studied: apparent density, morphogranulometry, roughness, and the specific surface through the adsorption-desorption of argon. Next, the relationship between the characteristics of talcs and their antisticking power was considered. Talc before and after delamination-which is a way to obtain talcs with different physical characteristics-was compared. Antisticking power appeared to be dependent on the basal dimensions of talc, and on the ratio value of the external specific surface measured by diffractometry to the total specific surface by the BET method. Models to express the effect of textural factors of talc particles on antisticking power were defined.

Developing a study method for producing 400 microm spheroids

The aim of this work was to obtain 400 microm spheroids that can be sprinkled on food to improve patient compliance particularly in the case of children and old people. A methodology to select wet masses for extrusion-spheronization through a 400 microm orifice was developed. The first step was to define the parameters that make it possible to assess the qualities required by the wet mass and the extrudates and evaluation norms: plasticity, cohesiveness, brittleness of the mass and the extrudates, and appearance of extrudates. A feasibility assay was then performed on the cylinder extruder, showing that extrusion of the lactose/Avicel PH 101/water (50/50/60) mass is not feasible through the 400 microm orifice. Precirol ato 5 and Gelucire 50/02 wetted with a sodium lauryl sulfate solution at 0.5% show plastic flow through the 400 microm diameter orifice. The presence of Avicel PH 101 does not improve plasticity for this orifice. Micropellets of 400 microm have been proved feasible as long as excipients with suitable pharmaceutical technological properties are used. After proving the feasibility of 400 microm spheroids of Gelucire 50/02, we considered the association of a drug with it.

Study of the technological parameters of ultrasonic nebulization

The principle of an ultrasonic nebulizer is based on the vibrations of a piezoelectric crystal driven by an alternating electrical field. These periodic vibrations are characterized by their frequency, their amplitude, and their intensity, which corresponds to the energy transmitted per surface unit. When the vibration in tensity is sufficient, cavitation occurs, and droplets are generated. Ventilation enables airflow to cross the nebulizer and to expel the aerosol droplets. For a given nebulizer, the vibration frequency of the piezoelectric crystal is fixed, often in the range 1-2.5MHz. In most cases, an adjustment in vibration intensity is possible by modifying vibration amplitude. The ventilation level is adjustable. The vibrations may be transmitted through a coupling liquid--commonly water--to a nebulizer cup containing the solution to be aerosolized. In this work, we studied the influence of the technological parameters of ultrasonic nebulization on nebulization quality. Our study was carried out with a 9% sodium chloride solution and a 2% protein solution (alpha1 protease inhibitor). Three different ultrasonic nebulizers were used. An increase in vibration frequency decreased the size of droplets emitted. The coupling liquid absorbed the energy produced by the ultrasonic vibrations and canceled out any heating of the solution, which is particularly interesting for thermosensitive drugs. An increase in vibration intensity did not modify the size of droplets emitted, but decreased nebulization time and raised the quantity of protein nebulized, thus improving performance. On the other hand, an increase in ventilation increased the size of emitted droplets and decreased nebulization time and the quantity of protein nebulized because more drug was lost on the walls of the nebulizer. High intensity associated with low ventilation favors drug delivery deep into the lungs.

Formulation of activated charcoal for per os administration to addicted subjects

The objective of this work was to develop a galenic form of activated charcoal appropriate for the needs of clinical toxicology. To preserve the adsorption capacity of charcoal, we developed an extemporaneous preparation of activated charcoal intended for clinical toxicology. To improve the wettability of activated charcoal, we used densification by wet granulation. The presence of a viscosity agent is necessary to ensure the homogeneity of the suspension and its adhesiveness on gastric mucous membrane. Five formulations with different viscosity agents were prepared, and their adsorption capacity, wettability, viscosity, and adhesiveness were studied.

[Feasibility of 400 microm spheroids by extrusion-spheronization]

Extrusion-spheronisation technology is an agglomeration process that makes it possible to obtain spheroids. The aim of this work was to obtain 400microm spheroids that could be sprinkled on food to improve patient observance in particular with children and old people. A methodology to select wet masses for extrusion-spheronisation through a 400microm orifice was developed. First, it was nesessary to define the parameters that make it possible to appreciate the qualities that the wet mass and the extrudates have to possess and their method of evaluation: plasticity, cohesiveness, brittleness of the mass and the extrudates, appearance of extrudates. A feasibility assay made on the drum extruder was then performed. After proving the feasibility of 400microm spheroids of Gelucire 50/02 we considered the association of a drug with it.

Influence of the technological parameters of ultrasonic nebulisation on the nebulisation quality of alpha1 protease inhibitor (alpha1PI)

The principle of an ultrasonic nebuliser is based on the vibrations of a piezo-electric crystal driven by an alternating electrical field. These periodical vibrations are characterised by their frequency, their amplitude and their intensity which corresponds to the energy transmitted per surface unit. When the vibration intensity is sufficient, cavitation appears and generates droplets. Ventilation enables an airflow to cross the nebuliser and to expulse the aerosol droplets. For a given nebuliser, the vibration frequency of the piezo-electric crystal is fixed and is often in the range of 1-2.5 MHz. In most cases, an adjustment in vibration intensity is possible by modifying vibration amplitude. The ventilation level is adjustable. The influence of these two parameters on the efficiency of ultrasonic nebulisation is studied. The study was carried out with a protein solution that had to be administered into the lungs. The solution used presented a viscosity of 1.25 mPa and a surface tension of 53 mN/m. The integrity of the protein was checked which was submitted to different vibration conditions. Nebulisation efficiency was evaluated by determining droplet size, the percentage of drug nebulised and nebulisation time. An increase in vibration intensity does not modify the size of droplets emitted, but decreases nebulisation time and raises the quantity of protein nebulised, thus improving performance. On the other hand, an increase in ventilation increases the size of droplets emitted, decreases nebulisation time and the quantity of protein nebulised because more drug is lost on the walls of the nebuliser. High intensity associated with low ventilation favours drug delivery deep into the lungs.

Influence of formulation on jet nebulisation quality of alpha 1 protease inhibitor

As foam appears during solution constitution and nebulisation of alpha 1 protease inhibitor (alpha 1 PI), we selected in a previous work, antifoams likely to be associated with an alpha 1 PI solution to be nebulised: span 65 at a 0.025% concentration and cetyl alcohol at a 0.05% concentration associated with tyloxapol at 0.025% concentration. The purpose of this study was, on the one hand to study the influence of the formulation on nebulisation quality by relating physicochemical properties and nebulisation capacity, and on the other hand, to define the alpha 1 PI that will be retained for a clinical study. The properties of the different alpha 1 PI formulations are compared: surface tension, viscosity, time required to constitute the protein solution and pH. Nebulisation quality is evaluated under different operating conditions by measuring the droplet size, the quantity of alpha 1 PI nebulised, nebulisation time and the quantity of alpha 1 PI likely to reach the lungs which was subjected to statistical analysis. The statistical analysis of results indicates that the addition of the cetyl alcohol/tyloxapol mixture improves nebulisation effectiveness by significantly increasing the quantity of drug nebulised and therefore the quantity of alpha PI likely to reach the lungs. It is this formulation that will be retained for clinical trials. We check that the nebuliser and operating conditions influence all the parameters, that is to say the respirable fraction, the quantity nebulised and the nebulisation time. Although there is no interaction between the nebuliser and the formulation, nebulisation quality is the combined result of the formulation, the nebuliser and the operating conditions.

The current 15N-leucine infusion technique is not suitable for quantitative measurements of ileal endogenous amino acid flows in pigs

The current 15N-leucine infusion technique may overestimate the ileal endogenous nitrogen losses in pigs. To determine the reason, we infused four cannulated pigs intravenously, fed them a pea-based diet with 15N-leucine, and examined some methodological variables. Neither the blood sampling time nor the choice of precursor pool (total N or amino acid N of deproteinized plasma) or the method of estimation of the isotopic equilibrium level significantly affected the results. On the other hand, the 15N-enrichment of purified mucin, isolated from ileal digesta, was higher than that of the plasma amino acid pool (0.114 vs. 0.077 atom % excess). The endogenous proportion of the labeled amino acids (Ala, Gly, Ile, Leu and Val) in the ileal digesta ranged from 23 (Leu) to 74% (Ala), compared with 70% for total N. The low value of leucine was ascribed to the constant marker infusion condition. In pigs infused with 13C-leucine, a similar endogenous proportion was obtained for lumenal leucine with 13C-leucine and 15N-leucine infusion. However, the 13C-enrichment of the leucine bound to mucin was markedly lower than that of plasma leucine (38%). The endogenous amino acid flows were also estimated by combining the ileal N flow measured with 15N and the endogenous amino acid profile obtained by means of an N-free diet. They were different from those obtained with the 15N-amino acid dilution technique. We conclude that the precursor pool currently used (plasma total N or total alpha-amino acid N pools) is a poor indicator of the enrichment of the secretions and that the infusion of one labeled amino acid is not sufficient to extend the method at the amino acid level.

The use of 15N-labeled dietary proteins for determining true ileal amino acid digestibilities is limited by their rapid recycling in the endogenous secretions of pigs

We assessed the use of 15N-labeled dietary proteins as a possible tool for the determination of the true ileal amino acid (AA) digestibility in pigs. The first experiment was designed to study the dietary N excretion pattern at the ileum subsequent to the ingestion of a single 15N-labeled meal. In a second experiment, we compared ileal endogenous AA outputs and true AA digestibility estimates obtained in pigs ingesting 15N-labeled dietary proteins in a single meal vs. intravenous infusion of [15N]leucine for 10 d during the ingestion of a pea-based diet and a protein-free starch diet. The proportion of endogenous N found in the ileal digesta differed when the label was delivered orally (50%) vs. intravenously (72%) and changed with time. As a consequence, the true ileal AA digestibilities measured with labeled diets were lower. A third experiment demonstrated that this was due to the rapid recycling of labeled dietary N in endogenous moieties, because 15N was found in blood within 10 min of consuming the labeled meal, within 50 min of consumption in pancreatic enzymes, 90 min in bile and 4 h in ileal mucins. We conclude that the use of 15N-labeled meals for determination of true ileal AA digestibilities is limited by the fast recycling of dietary N in endogenous secretions following a single 15N-labeled meal. The accuracy of results will depend on meaningful estimates of AA flow during a limited period and accurate estimates of 15N in AA.