Download or read book Assessment of Standardised Ileal Crude Protein and Amino Acid Digestibilities in Protein Supplements for Piglets written by Renata Urbaityte and published by Cuvillier Verlag. This book was released on 2009-06-08 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: A cautious assessment of standardised ileal digestibilities (SID) of crude protein (CP) and amino acids (AA) as a measure to describe AA bioavailabilities is critical for evaluating the protein value of feed ingredients for piglets. Estimates of SID have been generated for most feed ingredients for grower-finisher pigs, whereas corresponding values for piglets hardly exist. Until now, SID values determined in grower-finisher pigs are used in diet formulation for piglets as well. However, there is some concern that these values may not be valid in piglets due to a limited digestive capacity for feed protein in piglets. A guideline for the standardisation of the experimental procedure in digestibility experiments had already been proposed for grower-finisher pigs. These guidelines firstly include threshold levels for CP and AA in the assay diets to obtain so-called plateau apparent ileal digestibility values, which are independent of dietary CP and AA levels, and secondly values for IAALB. For piglets, similar guidelines, including dietary threshold levels and values for IAALB, have currently been established. Therefore, the objective of the thesis was, based on these guidelines, to determine SID of CP and AA in 24 assay feed ingredients, including 11 products from soybean processing, 7 by-products from starch processing, 2 fish meals and 4 whey proteins. For this purpose, a total of 4 digestibility experiments with piglets fitted with simple T-cannulas at the distal ileum was conducted. For each experiment, 14 barrows were weaned at 18 days of age. Each experiment consisted of 3 periods for digesta collection. A total of 24 semisynthetic cornstarch-based diets with various inclusion levels of casein were formulated to which 1 of the 24 assay feed ingredients each was added. The daily feed allowance was restricted to 30 g/kg of individual body weight throughout all experimental periods. The SID values were determined by difference to SID values in casein. The results of the present studies show large variations in SID values among differently processed soybean products (p0.05). The SID values in extruded soybeans (SBe) were lower compared to high-protein soybean meal (SBMhp), soy protein concentrate (SPC) or partially hydrolysed soy protein isolate (SPIh) (p0.05). Aqueous alcohol or water extraction in SPC or SPIh improved SID values compared to SBMhp (p0.05). The SID values among the 4 batches of SPC were similar (p0.05) and consistently high. Moreover, the SID values were similar in SPC and SPIh (p0.05). The SID values of in alternatively processed soy proteins including enzymatically fermented SPA and microbially fermented SPB, were inconsistent. For the 3 SPA products, SID increased numerically from values similar to SBMhp to values similar to SPC with increasing duration of enzymatic treatment. For SPB SID values were low and similar to SBe, which may be attributed to protein denaturation during microbial fermentation. The results of present study show for most AA similar SID values for all by-products of starch processing including pea protein (PeaP), wheat gluten (WG), corn gluten (CG), and potato protein (PotP) compared to SPC (p0.05) except for SID of Lys in WG and CG, and SID of Trp in CG were considerably lower compared to other products (p0.05). The particular low SID of Lys and Trp in WG and CG might be simply a reflection of an experimental error, because SID values by means of the difference method rely on sufficient high AA contribution levels to the assay diets, which was not achieved for the aforementioned AA. The results of the present study show that SID values in fish meal (FM1) and extracted fish meal (FM2e) vary considerably (p

Download or read book Evaluation of amino acid digestibility values of protein feedstuffs and dietary protein content in combination with probiotic supplementation in growing pigs written by Chanwit Kaewtapee and published by Cuvillier Verlag. This book was released on 2017-05-11 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the last decade, the concept of standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) has been used in diet formulation for pigs. However, there is limited data on the nutritional composition and SID of CP and AA in home-grown European soybean and rapeseed products. For full-fat soybeans (FFSB), the presence of heat-labile trypsin inhibitors may cause problems in protein digestion of pigs. Therefore, the optimization of heat treatment for FFSB is a need to reduce trypsin inhibitor activity for improving SID of CP and AA. However, excessive heat treatment may have a negative effect on protein digestion. Furthermore, reducing dietary protein levels in combination with the supplementation of Bacillus spp. may reduce feed costs and improve pigs’ gut health. As a result of the present study, home-grown European soybean and rapeseed products can be considered as a suitable alternative to imported soybean products for pigs raised in organic and conventional farming systems. Wet heating at 100°C for 16 min, together with autoclaving at 110°C from 15 to 45 min reflects optimal heat treatment for FFSB resulting in greater SID of CP and AA with lower destruction of AA. Reducing the dietary CP level is an alternative strategy to improve SID of some AA, thereby decreasing feed cost and nitrogen excretion. The supplementation of Bacillus spp. promoted gene copy numbers of Roseburia spp., which may be beneficial due to ascribed health promoting properties of this butyrate producer.

Download or read book In Vivo and in Vitro Studies with Growing Pigs on Standardised Ileal Amino Acid Digestibilities in Grain Legumes written by Dagmar Jezierny and published by Cuvillier Verlag. This book was released on 2009-12-09 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since there is a general ban on meat and bone meal and its by-products in diets for livestock in the EU, it is crucial to focus on alternative protein feed ingredients to be used in pig nutrition. Beside soybean meal as a commonly used plant protein supplement, grain legumes may also be used as alternative protein sources in diets for pigs. Current protein evaluation system for feed ingredients for pigs are based on the concept of standardised ileal digestibilities (SID) of crude protein (CP) and amino acids (AA), but there is a scarcity of information on SID of CP and AA in grain legumes grown in Central Europe. Therefore, the objective of the thesis was to determine the chemical composition and the SID of CP and AA in seed-grade cultivars of faba beans (Vicia faba), peas (Pisum sativum) and lupins (Lupinus spp.) in growing pigs using the difference method. Furthermore, to obtain SID of CP and AA, the basal ileal endogenous CP and AA losses in growing pigs were estimated by means of regression analysis from apparent ileal digestible and total dietary contents of CP and AA. A further aim of the thesis was directed to the validation of an in vitro procedure for estimates of SID of CP and AA in the same grain legumes by means of a two-step enzymatic method with subsequent pepsin and pancreatin incubations. The in vitro predicted SID values were compared with their corresponding in vivo SID values. The chemical composition and SID values of CP and AA measured in faba bean, pea and lupin cultivars generally were in good agreement with tabulated values. The average SID of CP and most AA in lupin cultivars (CP, 87%) were higher than in pea (CP, 79%) or faba bean cultivars (CP, 76%) Comparably low SID values in some faba bean cultivars can be partly explained by their contents of condensed tannins. In contrast to SID values in faba bean cultivars, there were only small variations in SID values between individual cultivars of peas or lupins. Results of the in vitro experiment revealed that predicted SID of CP and AA do not provide direct estimates of SID values in grain legumes, because the in vitro predicted SID values were generally higher than in vivo SID values. The use of multiple linear regression analysis with grain legume species as a covariate resulted in strong linear relationships. Further investigations are warranted to study if these principles apply to other feed ingredients as well. Moreover, the use of in vitro predicted SID values in practical diet formulations for pigs needs to be further validated.

Download or read book Assessment of standardized ileal digestibility and basal ileal endogenous losses of amino acids associated with barley in growing pigs written by Hanna Spindler and published by Cuvillier Verlag. This book was released on 2016-07-26 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2013, more than 308 million tons of cereals were produced within the European Union, of which about 60 million tons were grown as barley. The protein content of barley is rather low when compared to protein feedstuffs such as soybean meal. However, due to its high dietary inclusion level, up to half of the protein requirement of pigs can be met by barley.

Download or read book Assessment of standardized ileal amino acid digestibility in different wheat genotypes and wheat concentrated distillers solubles in growing pigs written by Pia Rosenfelder and published by Cuvillier Verlag. This book was released on 2015-03-11 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wheat is the primarily cereal grain produced within the European Union. Due to its high starch content it is the dominating energy feed ingredient in diets for pigs. However, due to its high dietary inclusion level wheat can also supply considerable high amounts of crude protein (CP) and amino acids (AA) to the animal. Wheat co-products of bioethanol production are a valuable source of CP and AA in animal nutrition. Therefore, the objectives of the present thesis were to study the nutritive value of eight recently introduced wheat genotypes and of one liquid wheat co-product of bioethanol production for growing pigs. For this purpose a comprehensive analysis of nutrients in the assay feedstuffs was conducted and standardized ileal digestibility (SID) of CP and AA in growing pigs was determined. There were significant differences in SID of CP and AA between the eight genotypes of wheat. However, digestibility values were lower when compared to literature data, leading to the assumption that data in actual feed tables might result in an overestimation of the protein value of wheat. The liquid wheat co-product is a valuable source of CP, AA and energy in diets for pigs. It is superior to dried bioethanol co-products as it is not exposed to excessive heat treatment during manufacturing resulting in greater digestibility values. In der Europäischen Union ist Weizen die am weitesten verbreitete Getreideart. Aufgrund seines hohen Stärkegehalts wird Weizen in Mastschweinerationen als Energiefuttermittel eingesetzt. Bei hohen Anteilen in der Gesamtration kann Weizen jedoch auch einen erheblichen Beitrag zur Deckung des Rohprotein- (XP) und Aminosäuren (AS)- Bedarfs des Tieres leisten. Nebenprodukte aus der Weizenverarbeitung bei der Bioethanolproduktion sind eine wertvolle Eiweißkomponente in der Tierernährung, dazu zählen Trocken- und Flüssigschlempen. Ziele dieser Arbeit waren die Bestimmung des Futterwerts von 8 aktuell verfügbaren Weizengenotypen sowie eines flüssigen Weizenschlempefutters für Mastschweine. Zu diesem Zweck wurde eine umfangreiche Nährstoffanalyse der Versuchsfuttermittel durchgeführt, sowie die standardisierte praecaecale Verdaulichkeit (pcVQ) von XP und AS bei Mastschweinen untersucht. Es gab signifikante Unterschiede der pcVQ von XP und AS zwischen den 8 Weizengenotypen. Allerdings waren die Verdaulichkeitswerte geringer als in der Literatur angeben, so dass Daten aus aktuellen Futterwerttabellen möglicherweise den Proteinwert von Weizen überschätzen. Das flüssige Weizenschlempefutter stellt eine wertvolle XP-, AS- und Energiequelle für Schweine dar. Es ist Trockenschlempen im Nährwert überlegen, da es keiner intensiven Hitzeeinwirkung ausgesetzt ist und somit höhere Verdaulichkeitswerte aufweist.

Download or read book Nutrient and energy digestibility in weaned piglets as influenced by feeding level and origin of soy bean meal in the diet written by Miriam Goerke and published by Cuvillier Verlag. This book was released on 2014-11-12 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feed is the greatest single cost factor in pig production, and protein and energy accounts for the largest proportion of feed costs. Therefore, it is crucial that the protein and energy content of a diet is characterized in the best possible way. Over the past years, the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) has been introduced into diet formulation for pigs in several countries. Moreover, different energy systems are available for feed evaluation including digestible energy (DE), metabolizable energy (ME) and net energy (NE). For soybean meal (SBM), the most commonly used feed ingredient in pig diets, tabulated values for SID of AA in addition to DE, ME or NE contents have been determined in grower-finisher pigs rather than weaned piglets. Due to the lack of separate feed tables for piglets, tabulated values originating from experiments with grower-finisher pigs are being used for diet formulation in piglet feeding, although post-weaning feed intake (FI) is highly variable and often lower than 3 times the maintenance energy requirement of weaned piglets. Thus, it remains open, if values obtained with grower-finisher pigs can be used for piglets as well. Furthermore, in grower-finisher pigs it has been shown that dietary inclusion of SBM sources of different origins may affect SID of CP and AA. The influence of SBM origin on SID of CP and AA in piglets has not been investigated so far. Therefore, the first objective of the present thesis was to determine SID of CP and AA in a large variety of SBM sources sourced from different countries, whereas the second and third objective was to investigate the effect of FI level on apparent ileal digestibility (AID) and SID of CP and AA, as well as on apparent total tract digestibility (ATTD) of proximate nutrients and energy in weaned piglets. For this purpose, a digestibility experiment with a total of 36 (initial BW 5.6 kg) newly weaned pigs, surgically fitted with simple T-cannulas at the distal ileum, was conducted. The piglets were housed in metabolic crates, and were fed semi-synthetic diets based on cornstarch and 1 out of 18 different SBM batches originating either from Argentina (6 batches), Brazil (6 batches) or the United States (US; 6 batches). Diets were fed on three graded levels of FI corresponding to 30, 45 and 60 g per kg average body weight (BW) of piglets, equivalent to 50, 75 or 100 g/kg BW0.75 d or 1.9, 2.6 and 3.1 times the energy requirement for maintenance. The whole experiment was split in 3 consecutive parts with 12 piglets, each. Over the whole experiment, the piglets were randomly allocated to the different combinations of FI level and SBM, but balanced in order to achieve 3 identical experimental parts. Chapter 1 of the present thesis provides a brief introduction into the objective of this thesis, including background information on SBM production, composition, and a literature review about studies concerning the impact of SBM origin and the effect of FI level on nutrient digestibility in pigs. Chapter 2 includes information on the chemical composition and proximate constituents of the 18 SBM batches originating from Argentina, Brazil, or the US. The average content of CP was greater for Brazilian SBM (P ≤ 0.05) compared to the other 2 origins. Contents of most AA were greater (P ≤ 0.05) in Brazilian compared to Argentinean SBM batches. Amino acid contents in US SBM batches ranged between those from Argentina and Brazil. Average trypsin inhibitor activity was greatest (P ≤ 0.05) in Brazilian SBM. Mycotoxins were detected in 8 out of 18 SBM batches, but all mycotoxin levels were below their critical benchmarks. The contents of individual isoflavones varied considerably among SBM origins (P ≤ 0.05). The SID of Arg, Phe, Thr, Trp, Asp, Gly, and Ser were greater (P ≤ 0.05) for US compared to Argentinean SBM batches, and intermediate values were obtained for Brazilian SBM batches. The SID values were most variable within Argentinean SBM batches and most homogenous within US SBM batches, as indicated by a great and a small coefficient of variation, respectively. However, SID of CP and AA were not related to any of the analyzed chemical constituents. It was concluded that EU imports of SBM are generally of high quality. The obtained SID values contribute substantially to the expansion of databases on SID of CP and AA in SBM from the 3 major soybean-producing countries for piglets. However, SID values obtained with piglets were considerably lower compared with tabulated values originating from grower-finisher pigs. Thus, further studies are warranted to confirm that finally separate feed tables for ingredients used in diet formulation for piglets are required to account for these differences. In Chapter 3, the effect of 3 graded levels of FI on AID and SID of CP and AA in SBM based diets was determined in piglets. The AID and SID of most AA were quadratically affected by the FI level (P ≤ 0.05). Initially, both AID and SID of most AA increased up to 1.9 % units as the FI level was increased from 30 to 45 g/kg BW. Thereafter, these AID and SID values decreased by 2.6 and 2.7 % units, respectively, as the FI level was further increased from 45 to 60 g/kg BW. It was concluded that there is a significant effect of feed intake level, albeit of small magnitude, on AID and SID of CP and AA, which possibly has to be accounted for in feed tables, due to the high variability of voluntary FI post weaning. In Chapter 4, the effect of 3 graded FI levels on AID and ATTD of proximate nutrients and energy, as well as on estimates of dietary DE, ME and NE contents was investigated. Due to the graded level of FI, and thereby the graded intake of nutrients, ileal endogenous nutrient losses and/or total tract endogenous nutrient losses could be estimated by linear regression analysis, and true digestibility values as well as urinary endogenous N losses could be calculated. The AID of DM, N and energy as well as ATTD of neutral detergent fiber, acid detergent fiber and ether extract (EE) in the assay diets was not affected (P > 0.05) by FI level. However, there was a small decrease in ATTD of DM, N, OM, ash and energy, as well as in DE, ME and NE content in the assay diets (P

Download or read book Standardized ileal amino acid digestibility and basal endogenous losses of amino acids in different genotypes of rye and triticale fed to growing pigs written by Elisa Strang and published by Cuvillier Verlag. This book was released on 2017-06-01 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cereal grains, such as rye and triticale are a major source of energy in pig nutrition. The crude protein (CP) content in cereal grains is rather low compared to protein ingredients such as soybean meal. However, costs and availability of soybean meal are strongly correlated with the price development of agricultural commodities on the world market. Therefore, swine producers will make increasing efforts to use protein from locally produced cereal grains more efficiently to reduce feed costs. Measurements of apparent (AID) and standardized ileal digestibility (SID) of CP and AA are frequently used to estimate the amounts of absorbable AA from the diet which are used for pigs’ metabolic processes. However, until now there is limited data on SID of CP and AA in rye and triticale, particularly in new genotypes. Therefore, one objective of the present work was to determine the variation in nutritional composition and SID of CP and AA of 8 currently available rye and 8 triticale genotypes. Standardized ileal digestibility of CP and most AA between the 8 assayed genotypes of both rye and triticale did not differ. Furthermore, average SID values of CP and AA of both rye and triticale in the present experiment were lower when compared to values of rye and triticale published in current feed tables. Thus, future research should clarify, whether these differences in comparison to feed tables are caused by experimental conditions or reflect a consistent decrease that need to be accounted for in feed tables.

Download or read book Nutritional and Physiological Functions of Amino Acids in Pigs written by Francois Blachier and published by Springer Science & Business Media. This book was released on 2013-04-08 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides developmental data regarding piglets (with a focus on the gastrointestinal tract), data related to amino acid metabolism in pigs, data related to nutritional and physiological functions of amino acids in pigs, nutritional requirements for amino acids in pigs, signaling roles of amino acids, methodological aspects in amino acid research and the pig model for studying amino acid-related human diseases.

Download or read book Experiments with Pigs written by Robert W. Clark and published by . This book was released on 1912 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A New Concept for Practical Feed Evaluation Systems written by Sigurd Boisen and published by . This book was released on 2007 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: Basic principles for feed evaluation; Potential physiological; energy; Potential digestibility of nutrients; Stadardised digestible amino acids; Ideal protein; Protein quality of feedstuffs; Energy evaluation of the major components in feedstuffs and pig diets; Starch as energy reference for other nutrient fractions; Ileal digestible carbohydrates; Ileal digestible lipids; Ileal digestible protein; Anti-nutritional factors (ANF'S); The practical performance of the new danish feed evaluation system; Basal chemical analyses, factors and equations; Calculation of energy value (PPE); Standardised digestible amino acids (SDAA) in feedstuffs and diets; Amino acid recommendations; Feed optimisation based on SDAA and PPE; The new danish feed evaluation system compared with other systems; Further developments and improvements in feed evaluation and pig production; Feed evaluation and optimisation of diets in practise; Feeding techniques and feeding strategy; General principles for a step-wise feed evaluation based on the new danish system.

Download or read book Protein Quality Evaluation written by Food and Agriculture Organization of the United Nations and published by Food & Agriculture Org.. This book was released on 1991 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Standardized Ileal Digestibility of Amino Acids and Metabolic Availability of Methionine in Partially defatted Black Soldier Fly Larvae Meal Fed to Growing Pigs written by Fiona Tansil and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: As food and animal protein demand increases, black soldier fly larvae (BSFL) meal has gained interest in the past couple of years for use in animal feed as an alternative protein ingredient. Black soldier fly larvae is an attractive protein source; however, it is important to evaluate its amino acid (AA) digestibility and metabolic availability (MA) before incorporation in feed formulation. The global objectives of this thesis were to determine the standardized ileal digestibility (SID) coefficient of AA and MA of methionine using the indicator AA oxidation (IAAO) method from BSFL meal, and to compare the results from the two protein quality methodologies. The SID coefficient of indispensable AA in BSFL meal was found to be above 83%, while the MA of methionine was found to be 53.33%. This finding further confirms that SID coefficient tends to overestimate AA bioavailability and that MA is a more accurate representation of bioavailability.

Download or read book Recent Developments in Pig Nutrition 2 written by Philip C. Garnsworthy and published by Hyperion Books. This book was released on 1993 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: Changes in consumer perceptions of meat quality; Nutritional manipulation of carcass quality in pigs; Consequences of changes in carcass composition on meat quality; Energy-protein interactions in pigs; Comparison of arc and nrc recomended requirements for energy and protein in growing pigs; Amino acid nutrition of pigs and poultry; Methods of determining the amino acid requirements of pigs; Ileal digestibilities of amino acid in pig feeds and their use in formulating diets; Use of synthetic amino acids in pig and poultry diets; Towards an improved utilization of dietary amino acids by the growing pig; Role of dietary fibre in pig feeds; Phosphorus availability and requirements in pigs; The water requirement of growing-finishing pigs - theoretical and practical considerations; Water for piglets and lactating sows: quantity, quality and quandaries; The phisiological basis of electrolyes in animal nutrition; Manipulation of the gut environment of pigs; Acidification of diets for pigs; Aetiology of diarrhoea; Immunity, nutrition and performance in animal production; Novel approaches to growth promotion in the pig; Impact of somatotropin and beta-adrenergic agonists on growth, carcass composition and nutrient requirements of pigs; Strategies for sow nutrition: predicting the response of pregnant animals to protein and energy intake; Predicting nuttrient responsesof the lactating sow; Nutrition of the working boar.

Download or read book Methodological Considerations for the Determination of Standardised Ileal Amino Acid Digestibilities in Piglets written by Meike Eklund and published by . This book was released on 2007 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dietary Protein Quality Evaluation in Human Nutrition written by [Anonymus AC10747383] and published by . This book was released on 2013 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Maillard Reaction written by H E Nursten and published by Royal Society of Chemistry. This book was released on 2007-10-31 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research in the field of the Maillard reaction has developed rapidly in recent years as a result of not only the application of improved analytical techniques, but also of the realisation that the Maillard reaction plays an important role in some human diseases and in the ageing process. The Maillard Reaction: Chemistry, Biochemistry, and Implications provides a comprehensive treatise on the Maillard reaction. This single-author volume covers all aspects of the Maillard reaction in a uniform, co-ordinated, and up-to-date manner. The book encompasses: the chemistry of non-enzymic browning; recent advances; colour formation in non-enzymic browning; flavour and off-flavour formation in non-enzymic browning; toxicological aspects; nutritional aspects; other physiological aspects; other consequences of technological significance; implications for other fields; non-enzymic browning due mainly to ascorbic acid; caramelisation; inhibition of non-enzymic browning in foods; and inhibition of the Maillard reaction in vivo. The Maillard Reaction: Chemistry, Biochemistry, and Implications will be welcomed as an important publication for both new and experienced researchers who are involved in solving the mysteries and complexities of Maillard chemistry and biochemistry. It will also appeal to students, university lecturers, and researchers in a variety of fields, including food science, nutrition, biochemistry, medicine, pharmacology, toxicology, and soil science.

Download or read book In Vitro Digestion for Pigs and Poultry written by M. F. Fuller and published by Oxford University Press, USA. This book was released on 1991 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: What are we trying to simulate?; Digestive enzyme activities in pigs and poultry; The role of the microflora in digestion; The physical and chemical constitution of foods: effects on carbohydrate digestion; Indirect effects of foods antinutrients on protein digestibility and nutritional value of diets; In vitro simulation of digestion and absorptionin the gastro-intestinal tract of pigs and poultry - methods and results; The chemical and biological bases of a calculation system developed for predicting dietary energy values: a poultry model; Enzyme modelling of protein digestion and L-lysine availability; Use of pepsin digentibility, multienzyme pH change and protein solubility assays to predict in vivo protein quality of feedstuffs; Estimation of true ileal digestibility of amino acids with pigs by an in vitro method using intestinal fluid; prediction of the energy value of non-ruminant feeds using in vitro digestion with intestinal fluid and other chemical methods; A model for feed evaluation based on in vitro digestible dry matter and protein; In vitro simulation of protein digestion: an integrated approach; Simultaneous estimations of precaecal protein and carbohydrate digestion in the pig; The way forward; the future requirements of the feed industry; The scientific challenge.