True Metabolizable Energy and Amino Acid Digestibility of Distillers Dried Grains with Solubles

In recent years, policies encouraging the production of ethanol have stimulated an enormous increase in the production of distillers dried grains with solubles (DDGS). The form of the ingredient that is becoming increasingly available differs from that of previous decades in that it is derived almost entirely from corn and is dried under less severe conditions. Seventeen DDGS samples were obtained from 6 different plants in the midwestern United States from 2002 to 2004. Each sample was analyzed for TME_n, and 8 representative samples were analyzed for total and digestible amino acids (AA) by the precision-fed rooster assay using conventional or cecectomized Single Comb White Leghorn roosters, respectively. Color [lightness (L*), redness (a*), and yellowness (b*)] of each DDGS sample was measured with a Minolta Chroma Meter CR-300. The TME_n ranged from 2,490 to 3,190 kcal/kg (86% DM basis) and had a mean of 2,820 kcal/kg. Variation was noted among samples, presumably reflecting differences in the original corn composition, fermentation, and disposition of solubles. Considerable differences were observed among the true AA digestibilities of the DDGS samples. Most samples were golden in color, and true AA digestibility values were relatively consistent among these samples. The average total concentration and digestibility coefficients of several most limiting AA for the 8 DDGS samples were as follows: Lys, 0.71% (70); Met, 0.54% (87); cystine, 0.56% (74); Thr, 0.96% (75), Val, 1.33% (80), Ile, 0.97% (83); and Arg, 1.09% (84). Correlations were found among digestible Lys, Thr, Arg, His, and Trp and the yellowness (b*) and lightness (L*) of the DDGS samples. In general, DDGS samples that were more yellow and lighter in color had higher total and digestible AA levels. The variation in TME_n and AA digestibility observed among samples strongly indicated that confirmatory analyses should be conducted prior to using samples from a new supplier.     

Silage preparation and nutritive value of Chinese yam by-product

The objective of this experiment was to determine the ensiling characteristics, nutrient composition and nutritive value of Chinese yam by-product (CYBP) silage treated without additive (Control), with lactic acid bacteria (LY), with dried beet pulp (BY), or with mixtures of lactic acid bacteria and dried beet pulp (LBY) for a fermentation period of 150 days. The nutritive value of CYBP silage was studied in an in vivo digestibility trial using wethers in a 4 × 4 Latin square design. Addition of lactic acid bacteria and/or dried beet pulp greatly improved fermentation quality of CYBP silage. The pH was reduced to below 4.0 and lactic acid was produced at above 4.6% on dry matter basis. There were no statistical differences among treatments in the digestibilities of dry matter, organic matter, crude protein and energy in the silages, but neutral detergent fiber and acid detergent fiber digestibility were higher ( P  < 0.001) in wethers fed BY and LBY silages compared to the control and LY silages. It was estimated that total digestible nutrient and digestible energy in the CYBP silage averaged 79.1% and 14.3 MJ/kg on dry matter basis. The study suggests that CYBP can be well preserved by making a silage and it is a good potential energy source for ruminant diets.     

The metabolisable energy of a sample of maize dextrin for poultry

The digestible and metabolisable energy values of a sample of maize yellow dextrin, determined using five colostomised hens were 11.602 ± 0.276 and 9.142 ± 0.230 MJ/kg (2473±66 and 2185±55 kcal/kg), respectively. These values are 65 and 57 % respectively of the gross energy of the dextrin.     

籽粒苋籽实粉作为肉仔鸡日粮组分的营养价值评定

通过梯度饲养、消化代谢和比较屠宰试验,综合评定了籽粒苋籽实粉对星布罗(Star-bro)肉仔鸡的营养价值和对日粮氨基酸利用率的影响.结果测得籽粒苋籽实粉含可消化粗蛋白质132.75g/kg,表观代谢能13.44MJ/kg;日粮中纳入16％苋籽实粉,显著提高了氨基酸利用率和血浆游离赖氨酸、亮氨酸及甘氨酸浓度,日粮粗蛋白质和能量代谢率分别提高6.91％和5.33％,日粮中营养物质转化为胴体蛋白质、脂肪的效率及料肉比均得到改善.     

Growth and meat yield responses of Ross × Ross 708 male broilers fed diets formulated with distillers dried grains with solubles varying in ether extract content and inclusion rate from 1 to 49 days of age

An experiment was conducted to evaluate the effects of diets containing low-, moderate-, or high-oil dried distillers dried grains with solubles (DDGS) included at conventional- or increased-inclusion rates fed to 1,500 Ross × Ross 708 male broilers that were assigned to 60 floor pens from 1 to 49 d of age. Three sources of DDGS had ether extract composition of 6.06, 8.80, or 11.59%, on dry matter (DM) basis, representing low-oil, moderate-oil, or high-oil DDGS, respectively. Diets were formulated to contain corn, soybean meal, animal protein meal as the primary ingredients, and 1 of the 3 DDGS sources at either 5, 7, 9, or 11% (conventional-inclusion rate) and 8, 10, 12, or 14% (increased-inclusion rate) in the starter (1 to 14 d), grower (15 to 24 d), finisher 1 (25 to 34 d), and finisher 2 (35 to 49 d) periods, respectively. Apparent ME_n (low-oil:1,975, moderate-oil: 2,644, and high-oil: 3,137 kcal/kg) and digestible amino acid (AA) values of the 3 DDGS sources were determined from previous research. No differences were detected for cumulative BW gain and feed conversion 1 to 49 d of age or meat yields at 50 d of age. Feeding broilers diets containing the low-oil DDGS source increased feed cost per BW gain and breast meat weight of $0.025/kg and $0.004/kg compared with birds fed diets containing high-oil DDGS or moderate-oil and high-oil DDGS sources, respectively. These data indicated that DDGS source and inclusion rate did not affect cumulative growth and carcass characteristics of broilers from 1 to 50 d of age but demonstrate differences in feed cost/BW gain and feed cost/breast meat weight.     

麦麸猪消化能与能量消化率预测方程的建立

本试验旨在测定麦麸的猪消化能(DE)及麦麸各化学成分对DE与能量消化率(DCE)的影响,分析用麦麸化学成分建立其DE与DCE的预测方程。试验选用12头三元杂交(杜×大×长)去势公猪[初始体重为(36.6±2.9)kg],采用2个6×6拉丁方试验设计(6期,11种饲粮),应用全收粪法测定10种不同产地和批次麦麸的DE,通过分析麦麸原料中的粗蛋白质(CP)、粗纤维(CF)、酸性洗涤纤维、中性洗涤纤维、淀粉(St)、粗脂肪、粗灰分、总能与DE及DCE之间的相关关系,筛选出最佳的预测因子并建立预测方程。结果表明:10种麦麸的平均DE为11.72 MJ/kg(干物质基础),平均DCE为61.31%,St为DE和DCE的最佳预测因子。推荐DE预测方程:DE=0.31×St+3.71(R2=0.76,RSD=0.42,P<0.01)、DE=-0.91×CF-0.71×CP+33.80(R2=0.76,RSD=0.35,P<0.01)。推荐DCE预测方程:DCE=1.70×St+22.28(R2=0.76,RSD=2.89,P<0.01),DCE=-5.02×CF-3.65×CP+182.81(R2=0.80,RSD=1.79,P<0.01)。由此可知,本试验利用麦麸原料营养成分建立的DE及DCE的预测方程相关指数较高,且由本试验结果预测的DE值比较准确。     

Hatchery Feeding of Starter Diets to Broiler Chicks

This study examined hatchery feeding of starter diets differing in amino acid density and moisture on live performance measurements up to 37 d and processing measurements at 38 d. Eggs from a Cobb × Cobb 500 slow-feathering cross broiler strain were set in a common incubator and hatched. Chicks were feather-sexed, placed in 36 chick trays (25 chicks of each sex), and weighed by tray. One of 4 dietary treatments was administered (454 g/tray) in crumble form: 1) no feed; 2) feed containing 1.24% digestible Lys, 0.84% digestible TSAA, 0.80% digestible Thr, 23.2% CP, and 3,080 kcal/kg of ME; 3) feed containing 1.45% digestible Lys, 0.94% digestible TSAA, 0.84% digestible Thr, 26.0% CP, and 3,080 kcal/kg of ME; and 4) treatment 3 plus 100 mL of potable water added to the crumbles 5 min before administration in the trays. Chicks received feed treatments in trays in the hatchery, during transportation to the research facility, and in the research facility until placement (5 h of total tray feeding). Body weight gain at d 7 was increased in birds fed the high density diet alone or in combination with water as compared with birds that were fasted. Subsequent live performance, processing, and small intestine weights, however, did not differ among treatments. Lack of 37-d improvements (average 4.6-lb birds) to early feed allocation may be a result of diet composition, duration of diet allocation, and the genetic strain of bird used, because much literature has pointed to the importance of posthatch nutrition of broilers.     

Growth performance and carcass characteristics of male broilers fed diets varying in digestible threonine to lysine ratio from 21 to 49 days of age

Two experiments were conducted to ascertain digestible Thr to Lys ratio of male broilers from 21 to 35 d of age (experiment 1) and 35 to 49 d of age (experiment 2) based on growth performance and processing yields. In both experiments, 2 diets (dilution and summit; 3,108 kcal ME/kg and 18.2% CP in experiment 1; 3,163 kcal ME/kg and 17.2% CP in experiment 2) consisting of corn, soybean meal, poultry by-product meal, and peanut meal formulated to be surfeit in limiting amino acids with exception of digestible Lys and Thr were mixed at various proportions to create 8 titration dose-response diets. Digestible Lys was formulated to contain 95% of the requirements from 21 to 35 and 35 to 49 d of age. In each experiment, gradient treatment structure was arranged in a randomized complete block design. Calculated digestible Thr to Lys ratios ranged from 0.512 to 0.806 in approximately increments of 0.040 (1,600 Hubbard × Cobb 500 broilers; experiment 1) and 0.552 to 0.793 in approximately increments of 0.035 (3,000 Ross × Ross 708 broilers; experiment 2). In experiment 1, digestible Thr to Lys ratio for male Hubbard × Cobb 500 broilers was estimated at 0.68 and 0.67 for BW gain and feed conversion from 21 to 35 d of age. In experiment 2, digestible Thr to Lys ratio of Ross × Ross 708 was determined at 0.68 and 0.63 for feed conversion ratio with quadratic and linear broken-line models, respectively. Meat weights and yields were not affected by the dietary treatments in either experiment. These data indicate that a digestible Thr to Lys ratio of 0.68 can optimize growth performance of broilers from 21 to 35 and 35 to 49 d of age.     

山东省羊常用粗饲料营养价值评定

试验旨在综合评价从山东省17个市采集的羊常用粗饲料原料的营养价值。试验测定了109个样本10种常用原料的常规营养成分及总能(GE),应用两级离体消化法测定干物质消化率(IVDMD),以计算消化能(DE)和代谢能(ME),并根据预测干物质随意采食量(DMI),进而计算出分级指数(GI)。结果表明,不同粗饲料间的常规养分的差异不能准确地评价饲料营养价值;以NDF、ADF所得GI综合评价粗饲料中营养价值得到苜蓿>冬牧70>地瓜秧>羊草>花生秧>青贮玉米秸>玉米秸>水稻秸>豆秸>麦秸;IVDMD与NDF、ADF均呈显著负相关,而与CP呈显著正相关;DE与NDF、ADF相关性较强,且均呈负相关。     

Evaluation of a high-protein DDGS product in broiler chickens: performance,nitrogen-corrected apparent metabolisable energy,and standardised ileal amino acid digestibility

ABSTRACT

1. New production processes and additional uses for corn co-products have increased the availability of distiller’s dried grains with solubles (DDGS) with varying energy and amino acid digestibility, for use in poultry feed. The objective of this study was to determine the performance, N-corrected metabolisable energy (AME_n), and amino acid (AA) digestibility of a 34% CP (as fed) high-protein DDGS (HP-DDGS) included in poultry diets for Cobb 500 broiler chickens.

2. A total of 832 Cobb 500 broilers were randomly assigned to four dietary treatments containing 5% conventional DDGS (CV-DDGS) as a control or 10%, 15% and 20% HP-DDGS and fed for 42 d. After the performance trial, 240 birds from the original 832 were selected for a concurrent AME_n and AA digestibility experiment consisting of two AME_n diets and two AA diets.

3. Birds fed diets containing 15% and 20% HP DDGS gained less weight than birds fed the CV-DDGS (P < 0.05) but did not differ in feed intake (FI), and therefore had a less efficient FCR than the control (P < 0.05). The AME_n of HP-DDGS was determined to be 11.4 MJ/kg. The standardised ileal amino acid digestibility (SIAAD) of the essential amino acids Lys and Met were determined to be 80.9% and 88.6%, respectively.

4. HP-DDGS can be included in broiler diets up to 10% without any negative impact on performance or requiring supplemental Lys and Arg. The results from the AA digestibility study indicated that HP-DDGS could be a good source of digestible Lys.     

Renal energy excretion of horses depends on renal hippuric acid and nitrogen excretion

The prediction of renal energy excretion is crucial in a metabolizable energy system for horses. Phenolic acids from forage cell walls may affect renal energy losses by increasing hippuric acid excretion. Therefore, the relationships were investigated between renal energy, nitrogen (N) and hippuric acid excretion of four adult ponies (230–384 kg body weight (BW)) consuming diets based on fresh grass, grass silage, grass cobs (heat‐dried, finely chopped, pressed grass), alfalfa hay, straw, extruded straw and soybean meal. Feed intake was measured; urine and faeces were quantitatively collected for three days. Feed was analysed for crude nutrients, gross energy, amino acids and neutral‐detergent‐insoluble crude protein (CP); faeces were analysed for crude nutrients and cross energy; urine was analysed for N, hippuric acid, creatinine and gross energy. Renal energy excretion (y; kJ/kg BW^0.75) correlated with renal N excretion (x₁; g/kg BW^0.75) and renal hippuric acid excretion (x₂; g/kg BW^0.75): y = 14.4 + 30.2x₁+20.7x₂ (r = .95; n = 30; p < .05). Renal hippuric acid excretion was highest after intake of fresh grass and lowest after intake of soybean meal. The ratio of hippuric acid to creatinine in urine and the excretion of hippuric acid per gram of dry matter intake was significantly higher for fresh grass than for all other rations. There was no relationship between aromatic amino acid intake and renal hippuric acid excretion. The results of the present study and literature data suggest that feed can be categorized into four groups with regard to the energy losses per gram CP intake: (i) protein supplements (e.g., soybean meal): 4.2–4.9 kJ/g CP intake (ii) alfalfa hay, grains, dried sugar beet pulp: 6.4 kJ/g CP intake, (iii) hay, preserved grass products, straw: 5.2–12.3 kJ/g CP intake (mean 8) and (iv) fresh grass. For group (iii) a negative relationship was observed between renal energy losses per gram of CP and the content of CP or neutral‐detergent‐insoluble CP in dry matter.     

水稻秸秆、麦麸、葡萄糖添加对绿狐尾藻青贮质量影响研究

为探究添加不同比例的水稻秸秆、麦麸与葡萄糖对新鲜绿狐尾藻青贮品质的影响规律，采用双因素完全随机设计，A因素为稻秸添加比例：0%，5%，10%，15%(相应计算麦麸和绿狐尾藻添加比例)；B因素为葡萄糖添加比例：0%，2%，4%，6%，青贮原料充分混合后青贮。结果表明：稻秸与葡萄糖添加比例及二者互作对青贮效果有显著或极显著影响(P<0.05或P<0.01)。随稻秸添加比例增加，丁酸含量显著增加(P<0.05)，纤维含量极显著增加，粗蛋白含量极显著降低(P<0.01)；随葡萄糖添加比例增加，pH值显著下降(P<0.05)，可溶性糖含量极显著升高(P<0.01)，粗蛋白、纤维含量及有氧稳定性极显著降低(P<0.01)。综合来看，70%绿狐尾藻与30%麦麸混合青贮添加2%~6%葡萄糖可制备饲用品质和有氧稳定性均优的青贮饲料；添加5%或10%水稻秸秆并添加4%葡萄糖可制备原料成本更低的青贮饲料。     

Chemical composition,energy and amino acid digestibility in double-low rapeseed meal fed to growing pigs

Background:The nutritional value of rapeseed meal may be variable due to the variation of its chemical composition.And a precise understanding of the nutritional value of an ingredient is beneficial for the accurate diet formulation and reduction of feed costs.This study was conducted to determine the chemical composition,digestible energy(DE) and metabolizable energy(ME) content,and apparent ileal digestibility(AID) and standardized ileal digestibility(SID) of amino acids(AA) for growing pigs.Thirteen solvent-extracted double-low rapeseed meal(DLRSM) samples were obtained from the main double-low rapeseed producing areas in China.Methods:The DE and ME contents of the 13 DLRSM samples were measured in growing pigs(six pigs per DLRSM sample,average initial body weight(BW) = 48.3 kg).The AID and SID of AA of 10 DLRSM samples were determined in 12 crossbred barrows(average initial BW = 35.3 kg) by using two 6x6 Latin square designs.Each Latin square comprised one N-free diet and 5 DLRSM test diets.Results:The chemical composition of DLRSM varied among samples,and the coefficient of variation was greater than 10%for ether extract(EE),neutral detergent fiber(NDF),acid detergent fiber(ADF),calcium(Ca),and total glucosinolates.The AA content of DLRSM varied among samples especially for lysine(Lys) and methionine(Met).On a dry matter(DM) basis,the apparent total tract digestibility(ATTD) of gross energy(GE),the DE and ME and the ME:DE ratio of DLRSM averaged 62.39%,2862 kcal/kg and 2723 kcal/kg,and 94.95%,respectively.The mean value of SID of Lys was 70.52% which varied from 66.54-76.54%.The SID of crude protein(CP),Met,and threonine(Thr) averaged 72.81%,82.41%,and 69.76%,respectively.Conclusions:There was great variability in chemical composition especially in the concentration of EE,NDF and ADF,but no significant differences in energy content of the DLRSM samples were observed.In addition,the AID and SID of all AA were relatively similar among DLRSM samples except for that of Lys.     

Effect of diet on chemical composition of rabbits slaughtered at fixed body weights

Four hundred and thirty-two Spanish Giant rabbits were fed 12 diets of variable energy to protein ratio [kcal digestible energy (DE)/g digestible crude protein (DCP)] from weaning to slaughter, both at different ages and weights. Body composition analysis for various chemical components indicated that body weight accounted for the greatest part of the variation in these constituents. Sex influenced only the N content (P less than .05). Dietary E/P accounted for greater variability in body composition than crude protein or crude fiber content of the diet. High dietary E/P increased (P less than .001) the proportion of body fat and reduced the proportion of body protein. This effect was made more obvious by adjustment to equal rate of weight gain and it showed that there may be a greater influence of dietary E/P on body composition than previously recognized.     

Influence of Temperature on the Arginine and Methionine Requirements of Young Broiler Chicks

Two experiments were conducted with Ross × Ross broiler chicks in battery brooders from 7 to 21 d of age to determine the Arg and Met requirements of young broiler chicks at control (25°C) and warm (35°C) temperatures. In both experiments, 1-d-old broiler chicks were fed a corn and soybean meal based starter diet for 7 d. Six replications (2 replicates in each of 3 rooms per temperature) with 8 chicks each were used for each treatment. In experiment 1, the basal diet was based on corn (34.52%), whey (26.96%), corn gluten meal (16.53%), soybean meal (11.74%), and poultry fat (23% of CP and 3.20 kcal/g of ME_n). Six levels of Arg (0, 0.1, 0.2, 0.3, 0.4, and 0.5%), supplementing the basal diet containing 0.95% Arg, were the dietary treatments. A broken-line linear model was used to estimate chick Arg requirements. Based on body gain and feed conversion ratio (FCR) data, respectively, the Arg requirements of young Ross × Ross broiler chicks raised at 35°C were 1.15 ± 0.03% and 1.13 ± 0.02%, whereas those of chicks at 25°C were 1.26 ± 0.03% and 1.27 ± 0.02%. In experiment 2, the influences of temperature and dietary Arg on the Met requirements of young broiler chicks were investigated. The basal diet was based on corn (53.45%), soybean meal (37.72%), and poultry fat (23% of CP and 3.20 kcal/g of ME). Experiment 2 had a 6 × 2 factorial arrangement, with the basal diet (0.35% Met and 1.52% Arg) supplemented with 6 levels of dietary Met (0, 0.05, 0.1, 0.15, 0.2, or 0.3%) and 2 levels of dietary Arg (0 and 1.0%). When chicks were fed a corn-soybean meal basal diet containing 1.52% Arg, the Met requirements of young Ross × Ross broiler chicks raised at 35°C were 0.43 ± 0.02% and 0.43 ± 0.03%, whereas those of chicks at 25°C was 0.43 ± 0.01% and 0.48 ± 0.03%, based on body gain and FCR data, respectively. When Arg levels were increased to 2.52%, the Met requirement of young Ross × Ross broiler chicks was greater at both temperatures (P < 0.05). The requirements of chicks raised at 35°C were 0.50 ± 0.02% and 0.49 ± 0.02% and at 25°C were 0.59 ± 0.03% and 0.57 ± 0.02%, based on body gain and FCR data, respectively. Temperature and amino acid balance may both affect the amino acid requirements of broilers.     

Effect of postweaning feeding on the performance and energy balance of female rabbits at different physiological states

The feeding of a high-fiber and low-energy diet to young rabbit does from weaning to the first kindling was used to modify their body reserves, stimulate their energy intake, and reduce the energy deficit during the first lactation. Rabbits (53 per group) were given ad libitum access to either a control or high-fiber diet (CP, 17.6 vs 15.8% of DM; crude fiber, 15.5 vs 19.9% of DM; digestible energy, 2,565 vs 2,261 kcal/kg of DM, respectively) from weaning to their first kindling. During lactation, both groups received the same diet, which contained 19.3% CP, 16.5% crude fiber, and 2,634 kcal/kg digestible energy (dry matter basis). Four comparative slaughters were performed to estimate the chemical and energy balance of rabbit does at different physiological states: at the beginning of the trial (12 rabbits, 45 d of age), at mating (10 rabbits per group, 136 d), at kindling (10 rabbits per group, 167 d), and at the end of lactation (12 and 11 rabbits for the control and the high-fiber group, 197 d). Large changes in body weight and composition were observed between slaughters. From 45 d to mating, doe body fat and energy increased 7.93 and 4.64 times the initial content, respectively. During pregnancy, body protein concentration decreased from 203 to 186 g/kg. At the end of lactation, body fat and energy concentration were reduced to values close to those measured at 45 d of age. Dietary treatment affected body chemical and energy balance during pregnancy and lactation but not reproductive and lactational performance. The high-fiber diet stimulated feed intake from weaning to the first kindling but not dietary energy intake. During lactation, the rabbits fed the high-fiber diet ate 10 kcal x d(-1) x kg live weight(-.75) more and lost less body fat (-405 vs -504 g) and body energy (-3,628 vs -4,294 kcal) than the does fed the control diet (P < .001). In the same period, all does showed water and protein retention (185 and 45 g, on average) regardless of dietary treatment. In conclusion, feeding young does a high-fiber diet until their first kindling reduced the chemical and energy body deficit at the end of the first lactation.     

Marginality and Needs of Dietary Valine for Broilers Fed Certain All-Vegetable Diets

Valine is likely the fourth limiting amino acid in most diets based on corn and soybean meal (C/SBM). However, the exact needs for Val are not well known, and information regarding it is sparse. A series of studies was conducted to validate the limitation of Val in all-vegetable diets fed to broilers, and subsequently to quantify an adequate ratio to Lys in high-yield late-developing broilers (Ross × Ross 708) from 21 to 42 d. A preliminary study was designed to evaluate the supplementation of different amino acids likely to be fourth limiting on a C/SBM-based diet, where Lys, TSAA, and Thr were supplemented but no other critical amino acids were given minimums in the formulation. Results obtained for BW gain, abdominal fat weight, and abdominal fat percentage showed that birds were more responsive (P < 0.05) to l-Val supplementation. A follow-up study using a corn-peanut meal (C/PM)-based diet formulated to be deficient in Val validated (P < 0.05) a Val deficiency based on poor growth performance and resulted in an immediate return to good performance when this amino acid was supplemented. Furthermore, the C/PM diet was compared with a nutritionally similar C/SBM diet, and no difference was observed in the performance of broilers fed these diets, thus validating the ability of the C/PM-based diet to support adequate growth of these broilers. This C/PM-based diet was used to feed gradual concentrations of Val, from levels that would be considered deficient (0.59% digestible) up to adequate (0.84% digestible Val). Results indicate that a ratio of Val to Lys of 78, or a minimum dietary value of 0.74% digestible Val (0.82% total Val), should be adequate for this high-yield broiler grown from 21 to 42 d of age.     

青贮蘑菇渣的营养品质及体外发酵特性评价

本文旨在评估蘑菇渣青贮料的营养品质、发酵特性及其与常规饲料原料的体外降解差异性。试验将收集的蘑菇渣作为原料,与米糠、糖蜜、垫料和菌种混合后青贮4周。分别在青贮0、7、14和28d时收集样品,用于评估营养品质、体外发酵特性,同时对比青贮蘑菇渣饲料与水稻秸秆和大麦秸秆的体外降解特性。结果:随着蘑菇渣青贮时间的升高,干物质含量显著降低(P<0.05),同时青贮7d后有机物含量也显著降低(P<0.05)。蘑菇渣青贮后,粗蛋白质和粗脂肪含量显著升高(P<0.05)。青贮7d后,粗灰分含量显著升高(P<0.05),而青贮7和28d后酸性洗涤纤维含量显著高于青贮0和14d(P<0.05)。蘑菇渣青贮7d后,pH显著升高(P<0.05),随后又显著降低(P<0.05),同时乙酸和丙酸含量显著降低,随后又升高(P<0.05)。蘑菇渣青贮后,乳酸和氨氮浓度显著升高(P<0.05),而水溶性碳水化物浓度显著降低(P<0.05)。青贮蘑菇渣的干物质组分中,水溶降解部分显著高于水稻秸秆和大麦秸秆(P<0.05),但不溶降解部分显著降低(P<0.05)且非降解部分显著低于水稻秸秆(P<0.05)。针对蛋白组分,青贮蘑菇渣水溶降解部分也显著高于其他两种原料(P<0.05),但不溶降解和非降解部分显著降低(P<0.05)。蘑菇渣青贮料中性洗涤纤维可消化部分显著低于水稻和大麦秸秆(P<0.05),不可消化部分则显著提高(P<0.05)。结论:以蘑菇渣为基础的青贮料发酵良好,可保存至第4周。以蘑菇渣为基础的青贮料干物质和粗蛋白质降解率远高于水稻、大麦和黑秸秆,中性洗涤纤维的降解率则相反。     

Nutrient database for distiller's dried grains with solubles produced from new ethanol plants in Minnesota and South Dakota

A study was conducted to evaluate the nutrient content and variability of distiller's dried grains with solubles (DDGS) originating from new (less than 5 yr old) ethanol plants in Minnesota and South Dakota. Ten plants (8 MN, 2 SD) participated in the study, submitting a total of 118 samples. Samples were collected every 2 mo from ten ethanol plants in the Minnesota-South Dakota (MNSD) region from 1997 to 1999 and were analyzed for amino acid levels, DM, CP, crude fiber, crude fat, ash, ADF, NDF, Ca, P, K, Mg, S, Na, Zn, Mn, Cu, and Fe analysis. Digestible energy (DE), ME, and NFE levels were also calculated. Means (dry-matter basis) and coefficients of variation for each nutrient among all plants during 1997 to 1999 were DM (88.9%, 1.7%), CP (30.2%, 6.4%), crude fat (10.9%, 7.8%), crude fiber (8.8%, 8.7%), ash (5.8%, 14.7%), NFE (45.5%, 6.1%), ADF (16.2%, 28.4%), NDF (42.1%, 14.3%), calculated DE (3,990 kcal/kg, 3.24%), calculated ME (3,749 kcal/kg, 3.28%), Arg (1.20%, 9.1%), His (0.76%, 7.8%), Ile (1.12%, 8.7%), Leu (3.55%, 6.4%), Lys (0.85%, 17.3%), Met (0.55%, 13.6%), Phe (1.47%, 6.6%), Thr (1.13%, 6.4%), Trp (0.25%, 6.7%), Val (1.50%, 7.2%), Ca (0.06%, 57.2%), and P (0.89%, 11.7%), respectively. Among the amino acids analyzed, Lys was the most variable (CV = 17.3%), followed by Met (CV = 13.6%). Nutrient levels of MNSD DDGS were higher in crude fat, NDF, DE, ME, P, Lys, Met, and Thr and lower for DM, ADF, and Ca than NRC (1998) values. Nutrient values differed between years for ash, DE, Mn, Zn, Cys (P < 0.10), Fat, TDN, ME, Met, Ile (P < 0.05), Ca, P, K, Mg, and Cu (P < 0.01). These results suggest that gross energy; P; and total Lys, Met, and Thr levels are higher in DDGS from MNSD ethanol plants compared to published values and chemical analysis values of a DDGS sample obtained from an older Midwestern plant.     

Protein and Energy Requirements of Pre-weaned West African Dwarf Goats Fed Soyabean Diet as a Replacement for Milk in a Tropical Environment

Twenty-one early-weaned West African dwarf goats weighing between 1.0 and 1.5 kg at birth were used to assess the protein and energy requirement of pre-weaned West African Dwarf (WAD) goats fed soyabean diet. Three isonitrogenous diets (24%) were prepared such that dried whole-milk protein was replaced by corn starch and soyabean concentrate protein at 0.0%, 25.0% and 50.0% levels such that a 14.5% total solid solution was obtained for each diet. Results indicated that a daily digestible energy (expressed as kcal/day/W0.75 kg) intake of 58.2, 63.7, 98.5 and 114.6 kcal was required for maintenance, while a corresponding value of 7.37, 4.50, 2.18 and 1.91 kcal was required per day per gram live weight gain by the kids at 4, 6, 9 and 13weeks old, respectively. Similarly, a digestible crude protein (DCP) intake of 3.59 g/day/W0.75 kg) appeared to be adequate for maintenance of the kids between 0 and 13 weeks, while 0.34 g/day/W0.75 kg of DCP intake was required per day per gram live weight.