Energy metabolisability and digestibility of amino acids by broilers fed on malted sorghum sprouts supplemented with polyethylene glycol, charcoal, phytase and xylanase

1. A precision feeding study was conducted to determine the metabolisable energy and amino acid digestibility in broilers fed on malted sorghum sprouts (MSP) supplemented with polyethylene glycol (PEG), charcoal (CH), phytase and xylanase. 2. A total of 64 male Ross broilers housed individually (8 replicates per treatment) were fed 30 g of the feedstuff as follows by gavage: MSP, MSP+1 g PEG/kg, MSP+10 g PEG/kg, MSP+1 g CH/kg, MSP+10 g CH/kg, MSP+3600 IU of evolved E. coli phytase/kg (EC 3.1.3.26) and MSP+1600 IU of bacterial xylanase/kg (EC 3.2.1.8). Another group of birds was used for the assessment of endogenous loss and they were provided with 50 ml glucose solution each by gavage. 3. True dry matter digestibility (TDMD), true nitrogen retention (TNR), total tract digestibility of apparent and true metabolisable energy (AME and TME) and amino acid (AAD and TAAD) were determined. 4. MSP contained 244.4, 24.0, 74.9 and 224.0 g/kg of crude protein, ether extract, ash and neutral detergent fibre, respectively. The total tannin content of the product was 140 g/kg and 99% of this was bound. 5. The various dietary treatments did not significantly affect the TDMD, TNR, AME and TME of MSP. The low values (0.471 g/g, -0.164 g/g, 6.15 MJ/kg and 9.31 MJ/kg, respectively) for the above measurements depicted the low feeding value of un-supplemented MSP for poultry. Also, PEG, CH and enzymes did not improve the AAD and TAAD of MSP for poultry. 6. It was concluded that the tannin content of MSP is high and it appeared to be bound with other nutrients thereby reducing their availability. This may explain its low AME and amino acid digestibility and the lack of effect of the various treatments for poultry.     

Effects of inclusion of poultry by-product meal and enzyme-prebiotic supplementation in grower diets on performance and feed digestibility of broilers

1. Two experiments were conducted to determine the effects of level of inclusion of poultry by-product and enzyme-prebiotic supplementation on grower diet digestibility and the performance of broilers. 2. Six grower diets were formulated to provide a similar nutrient profile with the exception of using three graded levels of poultry by-product, namely 0, 25, 40 g/kg of the diet with and without supplementation of enzyme preparation at the rate of 1 kg per tonne of feed and prebiotic preparation at the rate of 2 kg per tonne of feed. The experimental diets were used from 3 to 6 weeks of age. 3. Body weights, feed intake and feed conversion efficiency were not affected by poultry by-product; however, enzyme-prebiotic had a significant positive effect on feed conversion efficiency at 0 to 6 weeks in experiment 1. 4. Crude protein digestibility was decreased by feeding the diet containing poultry by-product while ether extract digestibility was increased by poultry by-product at the rate of 25 g per kg of feed only. Dry matter retention, crude fibre digestibility and organic matter retention were not affected by poultry by-product. Dry matter and organic matter retentions, crude protein, ether extract and crude fibre digestibilities were not affected by enzyme-prebiotic. 5. Protein efficiency ratio (PER) values were increased by poultry by-product at the rate of 40 g per kg of feed and addition of enzyme-prebiotic.     

Carob pod (Ceratonia siliqua) meal in geese diets.

1. The apparent and true metabolisable energy values of carob pods meal for geese were measured to be 6.1 MJ/kg and 6.6 MJ/kg respectively. 2. Performance from 5 to 12 weeks was examined in geese fed on four diets containing 0, 100, 200 and 300 g/kg of carob pods meal. 3. The inclusion of carob pods meal up to 200 g/kg in geese diets did not affect the performance. 4. At 300 g/kg performance was highly depressed. 5. The digestibility of protein in the diets decreased linearly with an increase in the level of inclusion of carob pods meal. 6. The length of small intestine, large intestine and caeca and the weight of gizzard expressed per kg of body weight increased with an increase in the level of carob pods meal, which is rich in fibre, in the diets.     

复合酶对临武鸭几种饼粕饲料原料养分利用率和代谢能的影响

本试验旨在研究复合酶(蛋白酶、纤维素酶和木聚糖酶)对临武鸭几种饼粕饲料原料(大豆粕、大豆渣、棉籽粕、2种菜籽粕、花生仁粕、2种芝麻粕)养分利用率和代谢能的影响。试验选用48只体重2.0 kg左右的健康成年临武鸭公鸭,随机分为6组,每组8个重复,每个重复1只鸭。采用绝食强饲-全收粪法进行3个批次代谢试验,每种原料均设对照组和添加复合酶组(试验原料中添加250 mg/kg的复合酶),对每只试验鸭强饲60 g试验原料,内源组强饲60 g无氮饲粮。测定添加复合酶条件下,临武鸭对8个饼粕饲料原料的表观代谢能(AME)、真代谢能(TME)及干物质(DM)、粗蛋白质(CP)、粗脂肪(EE)和粗纤维(CF)表观利用率和真可利用率。结果表明:临武鸭对8个饼粕类原料的DM、CP、EE和CF表观利用率分别为38.85%~62.86%、50.73%~65.39%、50.16%~74.50%和32.32%~46.46%,AM E和TM E分别为6.82~12.72 M J/kg,8.79~14.69 M J/kg,添加复合酶使临武鸭对几种饼粕饲料原料的DM、CP、EE和CF的有效营养改进值(ENIV)分别为6.25~21.70 g/kg、2.60~16.73 g/kg、0.13~8.66 g/kg和0.66~2.74 g/kg,TM E提高了0.19~1.15 M J/kg。由此可知,添加复合酶能够一定程度地提高临武鸭对饼粕饲料原料的养分利用率和代谢能。     

Effect of chicken age on the nutritive value of diets with graded additions of full-fat sunflower seed

1. Diets containing increasing amounts (80, 160 and 240 g/kg) of hulled full-fat sunflower seed (HFFSS) were evaluated for digestibility of nutrients and AMEn content with broiler chickens at 2 different ages (10 to 12 d and 27 to 29 d). 2. The age of chickens and dietary concentration of HFFSS had no major effect on the apparent digestibility of protein N and single amino acids. The differences observed were generally small and attained statistical significance only with glutamic acid, histidine, arginine, phenylalanine and isoleucine digestibilities. 3. The age effect on the apparent digestibility coefficients for crude fat and total fatty acids was dependent on the dietary concentration of HFFSS. Significant interactions between age and inclusion rate were observed for fat and individual fatty acids digestibilities. 4. AMEn (MJ/kg) increased significantly as the inclusion level of HFFSS increased. However, AMEn content was not affected by bird age or by the interaction between age and inclusion rate.     

Comparison of two direct bioassays using 3-week-old broilers to measure the metabolisable energy of diets containing cereals high in fibre: differences between true and apparent metabolisable energy values

1. Nitrogen-corrected apparent and true metabolisable energy contents (AMEN and TMEN) of 12 diets, containing different amounts of maize, wheat, barley and rye, barley with beta-glucanase and maize with 0.05 g/kg guar gum were measured using 3-week-old male broilers. 2. The AMEN method involved: 4 d of dietary adaptation, 24 h of starvation, 54 h of ad libitum feeding, 24 h of starvation and daily total droppings collection. TMEN was measured after a 48 h starvation period followed by 2 d of tube-feeding two doses of 15 g of the diets and quantitatively collecting all the droppings after 48 h of starvation. The endogenous energy losses (EELN) were measured after tube-feeding 8 chickens with 30 g of glucose, also over 2 d. 3. The results show that a significant interaction exists between the nature of the diets and the method used to measure metabolisable energy. Differences between TMEN and AMEN values ranged from 1.03 to 1.98 MJ/kg dry matter. These differences were positively correlated with the total pentosan contents of the diet (r = 0.94), the natural logarithm of the viscosities of the water extracts (r = 0.87), the sum of the contents of total pentosans and total beta-glucan (r = 0.85), the calculated total non-starch polysaccharide contents (r = 0.79), the neutral detergent fibre contents (r = 0.76) and the total beta-glucan contents (r = 0.70). Furthermore, a significant interaction was found between diets and the method used to derive lipid digestibility. The differences between apparent and true lipid digestibility ranged from 0.05 percentage points for the wheat diet to 0.20 percentage points for the rye diet. 4. From the results of this trial, it appears that TMEN overestimates the energy value of high fibre diets.     

The nutritive value of a sample of dried poultry manure for the laying hen

The composition of a commercially available sample of dried poultry manure (DPM) was determined and its nutritive value for the laying hen was examined using colostomised birds. The true digestibility coefficients of the true protein, crude fat, uric acid, total organic matter and carbohydrate were found to be 64.2, 69.5, 91.2, 25.5 and 23.1% respectively by regression analysis of absorbed vs. ingested nutrients. The true digestibilities of some of the constituent amino acids were found to range from 24.7% (for valine) to 76.4% (for serine). The absorption of calcium and phosphorus was characteristic of the individual bird and ranged from 1.2 to 45.3 % for calcium and from 7.5 to 46.2 % for phosphorus. The classical and nitrogen‐corrected metabolisable energy values were found to be 3.50 ± 0.16 and 3.35 ± 0.13 MJ/kg of dry matter respectively. It is concluded that DPM contains nutrients of value to the laying hen and that it could be incorporated into poultry diets in which energy content is of secondary importance and where use could be made of the calcium and phosphorus contents.     

The true metabolisable energy content of canola oilcake meal and full-fat canola seed for ostriches (Struthio camelus)

1. The true metabolisable energy (TME) of canola oilcake and full-fat canola seed was determined for ostriches to broaden our knowledge of canola as a potential protein and energy source for ostriches. 2. Both test materials were diluted with a basal diet, fed to ostriches and TME-values estimated by multiple regression analysis. 3. The TME values for canola oilcake meal and full-fat canola seed for ostriches were respectively 13.76 MJ kg(-1) and 22.5 MJ kg(-1). 4. The TME values obtained for these 2 important protein sources will assist in the more accurate formulation of diets for ostriches.     

复合酶制剂对几种糟渣类原料养分利用率和代谢能的影响

本试验旨在研究临武鸭对几种糟渣类原料(白酒糟、啤酒糟、2种酱油渣、灵芝菌糠、柑橘渣和甘蔗糖渣)的养分利用率和代谢能,及添加复合酶制剂(蛋白酶、纤维素酶和木聚糖酶)对几种糟渣类原料养分利用率和代谢能的影响。试验选用48只体重2.0 kg左右的健康成年临武鸭公鸭,随机分为8组,每组6个重复,每重复1只鸭。采用绝食强饲-全收粪法进行代谢试验,将待测原料与无氮饲粮按1∶2的重量比混合配成试验原料,每种原料均设对照组和添加复合酶制剂组(试验原料中添加250 mg/kg的复合酶制剂),对照组和添加复合酶制剂组的试验分2个批次进行,测定添加复合酶制剂对临武鸭几种糟渣类原料养分利用率和代谢能。结果表明:临武鸭对几种糟渣类原料的干物质(DM)、粗蛋白质(CP)、粗脂肪(EE)和粗纤维(CF)表观利用率分别为30.73%~51.08%、17.65%~75.62%、10.85%~91.19%和10.84%~67.05%,表观代谢能(AME)和真代谢能(TME)分别为4.58~15.20 MJ/kg和5.57~17.17 MJ/kg。添加复合酶制剂后临武鸭对几种糟渣类原料的DM、CP、EE和CF的有效营养改进值(ENIV)分别为6.46~41.37 g/kg、0.33~13.23 g/kg、0.09~9.73 g/kg和0.70~7.84 g/kg,TM E提高了0.13~1.68 M J/kg。由此可见,添加复合酶制剂能够一定程度地提高临武鸭对糟渣类原料的养分利用率和代谢能。     

饲粮粗蛋白质、能量水平对3岁梅花公鹿鹿茸生长和体增重的影响

为探讨 3岁梅花鹿生茸期饲粮适宜营养水平 ,本研究采用 2 (CP∶2 1%和 19% )× 2 (GE∶16 74MJ/kg和 15 90MJ/kg)二因子交叉设计 ,选用 3岁 (二锯 )梅花公鹿 6 7头 ,分为 4个试验组 ,进行了饲养试验和消化试验。试验结果表明 ,饲粮蛋白质水平对鹿体增重有显著影响 (P <0 0 5 ) ,在本试验所设能量浓度范围内 ,饲粮蛋白质水平为 19%处理组鹿体增重显著高于 2 1%蛋白组 ;鹿茸产量组间差异不显著 (P >0 0 5 ) ;饲粮粗蛋白质水平对蛋白质消化率和能量消化率均有显著影响 (P <0 0 5 ) ;3岁梅花鹿生茸期饲粮中能量、蛋白质适宜水平分别为 15 9～ 16 7MJ/kg (GE)和 19% (CP) ;平均每头鹿每天对消化能和可消化蛋白质的需要量分别为 2 9 9～ 31 3MJ和 388～ 394 g。     

不同净能水平的低蛋白日粮对猪生长性能和养分消化率的影响

选取120头22kg左右的杜×长×大三元杂交健康生长猪,随机分成5个处理,每个处理6个重复,每个重复4头,探讨低蛋白不同净能水平(10.54、10.28、9.96、9.63、9.45MJ/kg)日粮对生长猪生长性能和养分消化率的影响。结果表明:日粮蛋白降低4个百分点,不同净能处理间的采食量和饲料转化率没有显著差异(P>0.05),日增重随净能的下降呈线性增加,以9.45MJ/kg组最高(P<0.05);养分消化率中,除钙的消化率外,其余养分的消化率均随净能水平的增加而线性下降(P<0.05)。降低净能水平后,血清赖氨酸含量线性增加(P=0.03),对其余氨基酸影响差异不显著(P>0.05);对血清尿素氮含量的影响不显著(P>0.05)。由此可得出,低蛋白日粮中净能水平的降低并不影响生长猪的生长性能和养分消化率。     

Nutrient digestibility and prediction of metabolizable energy in total mixed rations for ruminants.

The aim of the present study was to determine equations that predict ME in total mixed rations (TMR) based on routine methods. The ME content of 30 TMR for dairy cows was determined based on digestible crude nutrients obtained with wether sheep. Concentrations in the TMR (in g/kg DM) varied between 118 and 234 for crude protein, 26 and 48 for crude lipid, 131 and 250 for crude fibre, 281 and 488 for NDF, and 173 and 304 for ADF. Gas production ranged from 40.7 to 54.1 ml/200 mg DM, and enzymatically degraded organic matter from 652 to 800 g/kg DM. Digestibility [%] ranged from 68.6 to 84.0 for organic matter, from 55.6 to 84.3 for crude lipid, from 55.0 to 77.8 for crude fibre, from 57.6 to 77.0 for NDF and from 53.1 to 79.6 for ADF. ME ranged from 9.6 to 11.9 MJ/kg DM, and NEL from 5.7 to 7.4 MJ/kg DM. ME content was highly correlated with the concentration of both crude fibre and enzymatically degradable organic matter as well as with organic matter digestibility. A multiple regression equation based on crude fibre and crude lipid predicted ME with a reasonable goodness of fit (r2 = 0.81; s(y.x) = 2.4%). The inclusion of other nutrients, of neutral and acid detergent fibre, neither of gas production did improve the goodness of fit. The best prediction was achieved with inclusion of enzymatically degraded organic matter (r2 = 0.90; s(y.x) = 1.7%).     

Effect of dietary inclusion of fermented pigeon pea (Cajanus cajan) meal on growth, apparent nutrient digestibility and blood parameters of cockerel chicks

The effect of dietary inclusion of fermented pigeon pea meal (FPPM) on growth response, apparent nutrient digestibility, haematological indices and serum biochemistry of cockerel chicks was studied using 240-day-old cockerel chicks allotted to four dietary treatments consisting of 60 birds each. Four experimental diets were formulated to include FPPM at 0, 50, 100 and 150?g/kg inclusion levels, respectively. Each of the diets was fed to 60 birds replicated six times with ten birds per replicate. The feeding trial lasted for 56?days. Results indicated that final live weight (linear (L). quadratic (Q): P??0.05) by the inclusion of FPPM. Haemoglobin and serum uric acid concentrations were also reduced (P?相似文献   

Energy evaluation of extruded compound foods for dogs by near-infrared spectroscopy

Near-infrared reflectance spectroscopy (NIRS) was used to predict the chemical composition, apparent digestibility and digestible nutrients and energy content of commercial extruded compound foods for dogs. Fifty-six foods of known chemical composition and in vivo apparent digestibility were analysed overall and 51 foods were used to predict gross energy digestibility and digestible energy content. Modified partial least square calibration models were developed for organic matter (OM), crude protein (CP), ether extract (EE), crude fibre (CF), nitrogen free extracts (NFE) and gross energy (GE) content, the apparent digestibility (OMD, CPD, EED, NFED and GED) and the digestible nutrient and energy content (DOM, DCP, DEE, DNFE and DE) of foods. The calibration equations obtained were evaluated by the standard error and the determination coefficient of cross-validation. The cross-validation coefficients of determination (R) were 0.61, 0.99, 0.91, 0.96, 0.94 and 0.92 for OM, CP, EE, CF, NFE and GE, the corresponding standard error of cross-validation (SECV) being 5.80, 3.51, 13.35, 3.64 and 16.95 g/kg dry matter (DM) and 0.29 MJ/kg DM respectively. The prediction of apparent digestibility was slightly less accurate, but NIRS prediction of digestible nutrient (g/kg DM) and DE (MJ/kg DM) gave satisfactory results, with high R (0.93, 0.97, 0.93, 0.83 and 0.93 for DOM, DCP, DEE, DNFE and DE respectively) and relatively low SECV (11.55, 6.85, 12.14 and 22.98 g/kg DM and 0.47 MJ/kg DM). It is concluded that the precision of NIRS in predicting the energy value of compound extruded foods for dogs is similar or better than by proximate analysis, as well as being faster and more accurate.     

棉籽浓缩蛋白营养价值评定及其对断奶仔猪生长性能的影响

本研究旨在评价棉籽浓缩蛋白的营养价值及其替代大豆浓缩蛋白对断奶仔猪生长性能、营养物质消化率和血清生化指标的影响。试验1：将12头生长猪随机分成2组（每组6个重复，每个重复1头猪），分别饲喂玉米基础饲粮和棉籽浓缩蛋白饲粮。采用全收粪尿法和套算法测定棉籽浓缩蛋白的消化能和代谢能。试验2：将12头生长猪随机分成2组（每组6个重复，每个重复1头猪），分别饲喂无氮饲粮和棉籽浓缩蛋白饲粮。采用指示剂法和直接法测定棉籽浓缩蛋白的粗蛋白质和氨基酸标准回肠消化率。试验3：将192头断奶仔猪随机分成4组（每组6个重复，每个重复8头猪），分别饲喂棉籽浓缩蛋白水平为0、2%、4%和6%（等量替代大豆浓缩蛋白）的试验饲粮，试验期28 d。结果表明：1）风干基础下棉籽浓缩蛋白消化能、代谢能和总能消化率分别为16.51 MJ/kg、15.38 MJ/kg和89.78%。2）棉籽浓缩蛋白的粗蛋白质和氨基酸标准回肠消化率89%和75%～94%。3）不同添加水平的棉籽浓缩蛋白替代大豆浓缩蛋白对断奶仔猪生长性能、营养物质消化率及血清生化指标均没有显著影响（P>0.05）。由此可见，棉籽浓缩蛋白在断奶仔猪饲粮中可以完全...     

Energy utilization by swine of nutritive fiber-rich by-products from the milling and food industry

Growing pigs (from 20 to 80 kg body weight) were fed diets containing equal amounts of soybean, pea (pisum sativum), millet and barley hulls as well as a mixture of these fibre sources. The effects of these fibrous components on the digestibility of energy and nutrients were investigated. Although some rations had a similar nutrient composition, important differences in the digestibility of energy could be observed: e.g. soybean hulls and pea hulls had a similar content in crude fibre but differed in the digestibility of energy by a factor 1:2. The difference in the digestibility of energy was even more pronounced between the rations with soybean hulls and millet hulls (factor 1:11, respectively) although the crude fibre and ADF fibre content were similar. Therefore the magnitude of the difference in digestibility of energy shows a considerable variation between the fibre sources. This seems to be caused partially by differences in the chemical nature of the fibrous by-products. Soybean hulls and barley hulls proved to be very well suited for growing pigs (11.4 MJ DE/kg DM and 10.0 MJ DE/kg DM, respectively). The pea hulls showed a mean content of digestible energy (5.6 MJ DE/kg DM) whereas the millet hulls (1.1 MJ DE/kg DM) didn't contribute significantly to the energy supply of the pigs.     

The development of a metabolizable energy system for horses

The development of a metabolizable energy (ME) system for horses is described. Predictive equations for gross energy and digestible energy (DE) are revisited. The relationship between feed protein content and renal energy losses and the relationship between feed fibre content and methane energy losses were analysed in a literature review to develop predictive equations for ME. In horses, renal energy losses are much higher than losses by methane energy. Renal energy losses were correlated more strictly to protein intake than to digestible protein intake. The reason probably is that per gram of digestible crude protein energy losses are higher for roughage than for concentrates presumably because phenolic acids of forage cell walls contribute to higher urinary energy losses. However, digestibility of protein is lower in forages than in concentrates. The net result is a rather constant urinary energy loss of 0.008 MJ/g of crude protein in the feed. Methane losses in horses are smaller than in ruminants, presumably because of reductive acidogenesis in hind gut fermentation. Methane energy losses in equines are closely related to crude fibre intake. The mean methane energy losses amount to 0.002 MJ ME/g of crude fibre which can be used to correct for methane losses. Both corrections can be made for any predictive equation for DE. Metabolizable energy is then calculated as follows: ME MJ/kg = DE MJ/kg – 0.008 MJ/g crude protein – 0.002 MJ/g crude fibre. The equation of Zeyner and Kienzle (2002) to predict DE was adapted as mentioned above to predict ME: ME (MJ/kg dry matter) = ?3.54 + 0.0129 crude protein+0.0420 crude fat?0.0019 crude fibre+0.0185 N‐free extract (crude nutrients in g/kg dry matter).     

Nutritional evaluation of sunflower seed and products derived from them. Effect of oil extraction

1. Apparent MEn and oil digestibility of hulled sunflower seed (SFS) and the products derived from the oil extraction process: press extracted SFS (PESFS), sunflower seed meal (SFSM), and press and solvent oils (PO and SO) were determined with 198 cockerels. Recombined products (mix of meal and oil) were also evaluated to study the effect of the 2 consecutive oil extraction steps. Each foodstuff was included in a basal diet, according to the proportions resulting from processing, at 100, 200, and 300 g SFS/kg. 2. Dietary energy value and digestible fat content were linearly related to rate of inclusion of test ingredients. Extrapolation values for AMEn (MJ/kg DM) were: SFS, 16.20; PESFS, 9.46; SFSM, 7.62. A decreasing quadratic trend was also found in the AMEn of PESFS, with interpolation values ranging from 11.77 to 9.33 MJ/kg DM between 70 and 210 g/kg DM of inclusion. No differences were observed between PO and SO. The AMEn of of sunflower oil, calculated from its digestibility, was 33.70 MJ/kg DM. 3. The oil extraction process affected the nutritional value of sunflower products. Recombined materials showed greater values than original foodstuffs: R-SFS, 17.47; R-PESFS, 11.49 MJ/kg DM. The increase in oil digestibility (from 0.814 to 0.862 g/kg DM in SFS; from 0.778 to 0.892 in PESFS) accounted for most of the increase observed in AMEn values. 4. As the form in which oil is incorporated in diets (released or within SFS or PESFS) affects the utilisation of sunflower products, their nutritional value is less than maximal and should not be calculated from their ingredients. Solvent oil seems to be the less available fraction of sunflower oil within SFS as the effect of the 2nd extraction proved to be greater than that of the previous press extraction.     

True ileal amino acid digestibility and endogenous ileal amino acid losses in growing pigs fed wheat shorts- or casein-based diets

Use of dietary AA in growing pigs reflects digestion and use of digested AA for various body functions. Before evaluating dietary effects on use of digestible AA intake for body protein deposition, a digestibility study was conducted to investigate true ileal AA digestibility and endogenous ileal AA losses in growing pigs fed graded levels of wheat shorts (WS) or casein (CS; control). A casein-based basal diet (basal) was formulated to contain 0.27 g of standardized ileal digestible (SID) Lys per MJ of DE, to which extra Lys was added from WS (WS2, +0.10 g of SID Lys per MJ of DE; WS3, +0.20 g of SID Lys per MJ of DE) or casein (CS3, +0.20 g of SID Lys per MJ of DE). A fifth diet was formulated to be similar in CP level and source as CS3 but in which 6% pectin, a source of soluble non-starch polysaccharides (NSP), was included at the expense of cornstarch (CS3 + pectin). Five Yorkshire barrows (17.5 +/- 1.5 kg of BW) were fitted with a T-cannula at the distal ileum and randomly assigned to 1 of the 5 experimental diets in a 5 x 5 Latin Square design. Apparent ileal digestibility (AID), true ileal digestibility (TID), and endogenous ileal protein losses (EPL) were determined using the homoarginine method. Diet CS level did not influence (P > or = 0.10) TID of most essential AA or EPL (10.4 g/kg of DM intake). Including pectin in the diet did not influence TID of AA (P > or = 0.10) but increased EPL (15.6 g/kg of DM intake; P > or = 0.01). Inclusion of WS in the diet reduced TID of most essential AA (P < 0.01). The TID values for most essential AA, however, were the same (P > or = 0.10) for both dietary WS levels, except for Lys and Met, which were further reduced at the greatest dietary WS level. Increased EPL (P < 0.01) was only observed for WS3 (16 g/kg of DMI). We concluded that (1) the effects of dietary protein source on AID of AA can be attributed both to reduced TID of AA and increased EPL, (2) the impact of dietary WS level on TID of AA and EPL does not seem to be linear, (3) soluble NSP from pectin or WS exerts a greater effect on EPL than insoluble NSP, and (4) because of the metabolic cost associated with EPL and the impacts of feed composition on microbial fermentation in the gut lumen, the effects of feed ingredients on the use of ileal digestible AA for protein deposition should be investigated further.     

Effect of inclusion level of linseed on the nutrient utilisation of diets for growing broiler chickens

1. Diets containing linseed at inclusions of 0, 80, 120 and 160 g/kg were evaluated for digestibility of nutrients and AMEn content with male broiler chickens. 2. Increasing the concentration of linseed decreased the retention of nitrogen and the digestibility of amino acids, crude fat and fatty acids of diets. 3. Dietary AMEn (MJ/kg) was also affected by the rate of inclusion of linseed, values decreasing from 14.39 to 12.49. 4. In general, a linear regression model explained the relationship between dietary linseed content and nutritive parameters. However, the quadratic response found for the digestibility of several amino acids and fatty acids indicated a non-additive change in their digestibility. 5. Viscosity ofjejunal digesta was markedly increased by each increment of linseed in the diets. This is attributable to the presence of mucilage in linseed and it might explain many of the results obtained in this study.