Nutritional and physiological responses of young growing rats to diets containing raw cowpea seed meal,protein isolate (globulins), or starch

The nutritional and physiological effects of raw cowpea (Vigna unguiculata (L) Walp.) seed meal, protein isolate (globulins), or starch on the metabolism of young growing rats have been evaluated in 14-day trials. Wet and dry weight gain, feed conversion efficiency, and lipid and protein accretion were significantly reduced as a result of inclusion of seed meal, globulins, or starch in the diet, with growth retardation being most marked with the seed meal. The proportional weights of the small intestine and pancreas were increased by meal diets, and serum cholesterol levels were slightly reduced. The globulins and raw starch also increased relative small intestine weights but had no effect on the pancreas or serum constituents. The effects of cowpeas on rats appeared to be due primarily to the combined actions of globulins, resistant starches, protease inhibitors, and possibly fiber and non-starch polysaccharides on intestinal and systemic metabolism.     

蛋白原料及其混合粉料理化性质对颗粒饲料加工质量的影响

该研究旨在探究豆粕、棉粕、菜粕、酒糟蛋白(Distillers Dried Grains with Solubles,DDGS)、乙醇梭菌蛋白5种蛋白原料及其混合粉料的营养指标和理化性质的差异,确定影响颗粒饲料质量和制粒能耗的关键指标,对5种蛋白原料的制粒效果进行综合评价。以豆粕为对照组,仅改变蛋白原料,采用相同的加工参数制备颗粒饲料,比较不同蛋白原料的制粒效果,进行主成分分析及偏最小二乘回归分析(Partial Least Squares Regression,PLS)。结果表明:在原料营养指标和理化特性方面,乙醇梭菌蛋白具有高蛋白含量、高蛋白溶解度、低脂肪、低纤维的特点,棉粕具有高纤维的特点,菜粕具有高纤维和低蛋白溶解度的特点,DDGS具有低蛋白和高脂肪的特点。蛋白原料吸水性强弱排列顺序为乙醇梭菌蛋白、豆粕、棉粕、菜粕、DDGS,水溶性与之相反。乙醇梭菌蛋白组和棉粕组的制粒能耗较高,豆粕组的制粒能耗最低;棉粕组和乙醇梭菌蛋白组的修正耐久性(Modified Pellet Durability Index,MPDI)较高分别为92.72%和90.57%,菜粕组的MPDI最低为79.68%;乙醇梭菌蛋白组的硬度最高为130.95N,DDGS组的硬度最低为74.26N;乙醇梭菌蛋白组的糊化度最高为45.56%,DDGS组的糊化度最低为31.36%。通过偏最小二乘回归模型得到,蛋白含量、蛋白溶解度和吸水性的增加会提高颗粒饲料硬度、PDI和MPDI;粗纤维含量、蛋白溶解度和吸水性的增加会增加制粒能耗。综合分析5种蛋白原料制粒特性,由高到低排序为乙醇梭菌蛋白、棉粕、豆粕、菜粕、DDGS。研究结果为实际生产颗粒饲料时蛋白原料的选择提供参考依据。     

Nutritional value of a highly digestible sorghum cultivar for meat-type chickens

The nutritional value of a newly discovered sorghum mutant cultivar (P851171), with high in vitro protein digestibility, was compared to those of corn and two normal sorghums (P721N and 611Y) in two chick feeding trials. Although 8-20 day protein efficiency ratios and net protein ratios of all three sorghums were inferior to those of corn, P851171 and 611Y had markedly greater mean true amino acid digestibilities (TAAD) than either corn or P721N. In a subsequent 42-day experiment, all three sorghums supported weight gains equal to those of the corn-fed chicks. Feeding suboptimal levels of dietary protein resulted in reduced weight gains and no observed benefits of P851171 or 611Y. Furthermore, chicks fed P851171 exhibited poorer feed/gain values as compared to those fed the other cereals. It is possible that the starch content/carbohydrate profile of P851171 was inferior to that of the other sorghums, which offset its superior TAAD and resulted in poorer broiler performance.     

Commercial Phaseolus vulgaris extract (starch stopper) increases ileal endogenous amino acid and crude protein losses in the growing rat

The effect of a commercial Phaseolus vulgaris extract (PVE, starch stopper) on ileal and fecal endogenous protein losses was studied. Growing rats were fed for 14 days a protein-free diet containing PVE at a nutritional concentration of 0% (PF1), 0.4% (PF2), or 1.1% PVE (PF3) or 1.1% autoclaved PVE (PF4). An indigestible marker (TiO(2)) was included in each diet. Ileal endogenous amino acid (AA) losses were significantly higher (P < 0.05) in PF3 (20% higher than in PF1), except for Pro, Gly, Ala, and His. Endogenous ileal N losses were 22% higher in PF3 than in PF1. Endogenous fecal AA and N losses were all significantly higher (P < 0.05) in PF3. Starch digestibility ( approximately 100%), food intake (single daily meal, d10-23), and body weight loss were not significantly different among the groups. PVE, at 1.1% of the diet, not only was ineffective in reducing starch digestibility but also led to increased ileal endogenous N losses, possibly due to the antinutritional factors (trypsin inhibitor, lectin) present in the PVE.     

Nutritional assessment in vitro and in vivo of raw and extruded peas (Pisum sativum L.)

The effects of extrusion cooking on the nutritional properties of Pisum sativum L. have been evaluated in vitro and in vivo. The treatment greatly elevated protein and starch digestibility in vitro. Also, the amounts of intact starch diminished while total free sugars increased. In addition, the levels of antinutritional factors, such as protease inhibitors and lectins, were greatly decreased. Concentrations of methionine and cystine were low in raw peas and were further reduced by extrusion treatment. The nutritional performance of rats fed extruded pea diets for 15 days was no better than that of rats given raw pea diet. This was due to the overriding effects of amino acid deficiencies in the diets. Weight gains by rats fed extruded pea diets supplemented with amino acids were, however, much higher than those achieved by rats fed supplemented raw pea diets. Food transformation index and protein efficiency ratio values were also greatly improved. Extrusion treatment did therefore significantly improve the nutritional quality of peas.     

Evaluation of detoxification methods on toxic and antinutritional composition and nutritional quality of proteins in Jatropha curcas meal

The Jatropha curcas meal was detoxified by different methods, and the effect of detoxification was evaluated in this study. The method that hydrolysis of enzymes (cellulase plus pectinase) followed by washing with ethanol (65%) had a significant (p < 0.05) effect on the toxin, antinutritional components, and nutritional quality of proteins. After this treatment, the phorbolesters (PEs) were decreased by 100%. The antinutritional components (phytates, tannins, saponins, protease inhibitor, and lectin activities) were decreased to tolerable levels, which were lower than those in soybean meal. The crude protein in detoxified meal was 74.68%, and the total content of amino acids was 66.87 g/100 g of dry matter. The in vitro protein digestibility (IVPD) increased from 82.14 to 92.37%. The pepsin-insoluble nitrogen was only 4.57% of the total nitrogen, and about 90% of the protein was true protein. The protein-digestibility-corrected amino acid score (PDCAAS) of the meal was 0.75. The results showed that this treatment was a promising way to detoxify J. curcas meal, and the nutritional quality of detoxified meal can be simultaneously enriched and improved.     

Carbon dioxide evolution from wheat and lentil residues as affected by grinding,added nitrogen,and the absence of soil

Summary A study was conducted to determine the effects of grinding, added N, and the absence of soil on C mineralization from agricultural plant residues with a high C:N ratio. The evolution of CO₂ from ground and unground wheat straw, lentil straw, and lentil green manure, with C:N ratios of 80, 36, and 9, respectively, was determined over a period of 98 days. Treatments with added N were included with the wheat and lentil straw. Although the CO₂ evolution was initially much faster from the lentil green manure than from the lentil or wheat straw, by 98 days similar amounts of CO₂ had evolved from all residues incubated in soil with no added N. Incubation of plant residues in the absence of soil had little effect on CO₂ evolution from the lentil green manure or lentil straw but strongly reduced CO₂ evolution from the wheat straw. Grinding did not affect CO₂ evolution from the lentil green manure but increased CO₂ evolution from the lentil straw with no added N and from the wheat straw. The addition of N increased the rate of CO₂ evolution from ground wheat straw between days 4 and 14 but not from unground wheat straw, and only slightly increased the rate of CO₂ evolution from lentil straw during the initial decomposition. Over 98 days, the added N reduced the amounts of CO₂ evolved from both lentil and wheat straw, due to reduced rates of CO₂ evolution after ca. 17 days. The lack of an N response during the early stages of decomposition may be attributed to the low C:N ratio of the soluble straw component and to microbial adaptations to an N deficiency, while the inhibitory effect of N on CO₂ evolution during the later stages of decomposition may be attributed to effects of high mineral N concentrations on lignocellulolytic microorganisms and enzymes.     

电子束辐照对饼粕类饲料中抗营养因子的影响

为了探讨电子束辐照对饼粕类饲料中抗营养因子的抑制作用,以1、2、3、5、7、9 k Gy剂量的电子束对豆粕、菜籽粕、棉籽粕等饲料进行辐照处理,研究辐照对大豆抗原、硫葡糖苷及其水解产物、植酸、单宁及游离棉酚的影响。结果表明,电子束辐照可有效降低饼粕类饲料中大豆球蛋白、硫代葡萄糖苷及其水解产物、植酸、单宁、游离棉酚等的含量,其中3 k Gy电子束辐照后,大豆球蛋白降低22.63%;7 k Gy下异硫氰酸酯降低17.17%,9 k Gy下噁唑烷硫酮、硫代葡萄糖苷、单宁、游离棉酚分别下降14.17%、15.83%、18.18%、13.17%,但电子束辐照对β-伴大豆球蛋白和胰蛋白酶抑制因子的抑制效果不显著。本研究结果为饼粕类饲料中抗营养因子的消除提供了理论参考。     

Effect of various domestic processing methods on antinutrients and in vitro protein and starch digestibility of two indigenous varieties of Indian tribal pulse, Mucuna pruriens Var. utilis.

The effect of various domestic processing methods on antinutrients and starch fractions and in vitro protein and starch digestibilities of white and black varieties of Mucuna pruriens var. utilis was studied. Cooking or autoclaving of both raw seeds and presoaked seeds in different solutions (water, tamarind extract, sodium bicarbonate, and citric acid) significantly (p < 0.05) reduced the content of total phenolics, phytic acid, trypsin inhibitor and chymotrypsin inhibitor activities, and L-dopa compared to soaking or dry heating techniques. The germination processes (24 and 48 h) were also effective in the reduction of various antinutrients, although this reduction appeared to be more pronounced in a prolonged period of germination (72 h). Water soaking followed by dehusking was found to be ineffective in the reduction of trypsin and chymotrypsin inhibitor activities in both varieties. All of the treatments were effective in significantly (p < 0.05) reducing the resistant starch content in the presently investigated samples. Cooking as well as autoclaving brought about a more significant (p < 0.05) improvement in the digestibility of protein and starch compared to germination and dry heat treatment. Moreover, among the different processing techniques, soaking in sodium bicarbonate solution followed by cooking (29.6-34.8%) or autoclaving (33.0-37.2%) seemed to be the best method for improving starch digestibility.     

Nutritional quality of sesame seed protein fraction extracted with isopropanol

The nutritional effect of diet containing decorticated sesame seed extracted with isopropanol (DSS-Iso) was evaluated on growth performance, food efficiency ratio, plasma and tissue lipid profile, plasma protein content, and erythrocyte membrane lipid profile of rats on a comparative basis with diets containing casein (control), soybean meal, and decorticated sesame seed extracted with hexane (DSS-Hex). Rats fed a DSS-Iso-based diet showed body weight gain and food efficiency ratio similar to those of the control groups fed diets prepared with casein, soybean meal, and DSS-Hex. However, dietary proteins exerted a separate effect on plasma lipid concentrations of the rats. Rats fed a DSS-Iso-based diet showed significant decreases in plasma total cholesterol (p < 0.01), triglyceride (p < 0.01), and VLDL+LDL cholesterol (p < 0.01) concentrations in comparison to the rats fed diet containing casein. No significant differences in plasma lipid concentrations were observed for the rats fed diets prepared with soybean meal, DSS-Hex, and DSS-Iso. Rats fed the different dietary proteins did not show much variation in plasma proteins, liver lipids, and erythrocyte membrane lipid concentrations, which suggests that DSS-Iso could be a suitable edible protein like casein or soybean meal.     

Small‐Scale Extrusion of Corn Masa By‐Products

Corn masa by‐product streams are high in fiber and are amenable for utilization in livestock feed rations. This approach is a potentially viable alternative to landfilling, the traditional disposal method for these processing residues. Suspended solids were separated from a masa processing waste stream, blended with soybean meal at four levels (0, 10, 20, and 30% wb), and extruded in a laboratory‐scale extruder at speeds of 50 rpm (5.24 rad/sec) and 100 rpm (10.47 rad/sec) with temperature profiles of 80‐90‐100°C and 100‐110‐120°C. Processing conditions, including dough and die temperatures, drive torque, specific mechanical energy consumption, product and feed material throughput rates, dough apparent viscosity, and dough density, were monitored during extrusion. The resulting products were subjected to physical and nutritional characterization to determine the effects of processing conditions for these blends. Extrudate analysis included moisture content, water activity, crude protein, in vitro protein digestibility, crude fat, ash, product diameter, expansion ratios, unit and true density, color, water absorption and solubility, and durability. All blends were suitable for extrusion at the processing conditions used. Blend ratio had little effect on either processing parameters or extrudate properties; extrusion temperature and screw speed, on the other hand, significantly affected both processing and product properties.     

复合菌剂对青贮玉米营养成分及其饲喂滩羊效果的研究

筛选复配适合宁夏地区的青贮微生物菌剂,可解决在青贮自然发酵过程中,青贮玉米营养损失多且易发霉等问题。本研究对从宁夏中部干旱区自然发酵的青贮玉米饲料中分离鉴定的1株乳酸菌(Lactobacillus acidophilus)和1株酵母菌(Saccharomyces cerevisiae)进行性能测定,复配后形成复合菌剂并进行45 d的大型窖贮青贮发酵试验,设置不添加菌剂和添加商业菌剂的青贮饲料为对照组。营养成分测定结果显示,与不加菌剂和添加商业菌剂的对照组相比,经复合菌剂处理后饲料中性洗涤纤维和酸性洗涤纤维显著下降(P0.05),干物质和粗脂肪含量显著增加(P0.05),粗蛋白含量变化不显著。为期75 d的滩羊肥育饲喂和5 d的消化代谢试验表明,对照组与试验组滩羊的日均采食量差异显著(P0.05),平均日增重、末重、料重比差异不显著。试验组滩羊对青贮玉米饲料中粗蛋白、粗脂肪表观消化率显著提高(P0.05),中性洗涤纤维表观消化率提高,对酸性洗涤纤维的表观消化率影响不显著。结果表明,复合菌剂显著改善了青贮玉米饲料的品质,复合菌剂发酵的饲料玉米对滩羊生长有良好的促进作用。     

Hydrolyzed casein influences intestinal mucin gene expression in the rat

The effect of hydrolyzed casein (HC) on the expression of three mucin genes (Muc2, Muc3, and Muc4) in the rat intestine was investigated using quantitative real-time polymerase chain reaction. After a 10 day acclimatization period, rats received for 8 days the test diets containing either HC or a synthetic amino acid (SAA) mixture as the sole source of nitrogen or a protein-free (PF) diet (n = 12 per treatment). The addition of HC or the SAA mixture to the diet significantly improved average daily gain, average daily food intake, and gain:feed ratio as compared with the PF diet. Terminal ileal endogenous N flow was significantly higher for the HC-fed rats in comparison with either the SAA or the PF rats (p < or = 0.001). HC supported a significant increase of Muc3 mRNA (277 and 229% of that for diets PF and SAA, respectively; p < or = 0.05) in the small intestinal tissue and Muc4 mRNA (325 and 265% of that for diets PF and SAA, respectively; p < or = 0.05) in the colon. In conclusion, HC enhances ileal endogenous N flow and up-regulates in vivo the expression of some individual mucin genes.     

Technological and Nutritional Properties of Flours and Tortillas from Nixtamalized and Extruded Quality Protein Maize (Zea mays L.)

Nixtamalized and extruded flours from quality protein maize (QPM, V‐537C) and tortillas made from them were evaluated for some technological and nutritional properties and compared with the commercial brand MASECA. Both QPM flours showed higher (P < 0.05) protein content, total color difference, pH, available lysine, and lower (P < 0.05) total starch content, Hunter L value, water absorption index, gelatinization enthalpy, resistant starch, and retrograded resistant starch than nixtamalized MASECA flour. Tortillas from nixtamalized and extruded QPM flours had higher contents of essential amino acids than tortillas from MASECA flour, except for leucine. Tortillas from processed QPM flours also showed higher (P < 0.05) values of the nutritional indicators calculated protein efficiency ratio (C‐PER 1.80–1.85 vs. 1.04), apparent and true in vivo protein digestibility (78.4‐79.1 vs. 75.6% and 76.4–77.4 vs. 74.2%, respectively), PER (2.30–2.43 vs. 1.31), net protein retention (NPR; 2.88–2.89 vs. 2.11), and protein digestibility corrected amino acid score (PDCAAS; 54–55 vs. 29% based on preschool children and 100 vs. 85% based on adults) than MASECA flour. The use of QPM for flour and tortilla preparation may have a positive effect on the nutritional status of people from countries where these products are widely consumed.     

苜蓿蛋白对仔猪和肉仔鸡生产性能的影响

研究比较苜蓿蛋白（ＡＪＰＣ）对仔猪和肉仔鸡的生产性能的影响。结果表明,苜蓿蛋白对仔猪和肉仔鸡的影响存在显著差异。在肉仔鸡日粮中用苜蓿蛋白替代豆粕和棉粕蛋白１０％以下时,苜蓿蛋白对肉仔鸡生长和采食量没有不良影响;替代５０％以上时,对采食量和生长都有显著的抑制作用（Ｐ＜０．０５）。苜蓿蛋白替代仔猪日粮中的棉粕和菜粕蛋白１００％时,对生长有显著改善（Ｐ＜０．０１）,生长速度分别提高１０．２％和４．８％。     

Glyphosate tolerant canola meal is equivalent to the parental line in diets fed to rainbow trout

Two separate studies were conducted to evaluate the utility of glyphosate tolerant canola (GTC) as a feed ingredient in diets fed to rainbow trout. In the first study, two forms of GTC were compared to a parental line, Westar. In the second study, one line of GTC was reevaluated to Westar. In each study, processed canola meals were incorporated at 5, 10, 15, or 20% of the dry diet and a diet containing no canola was fed for comparison. All diets were fed to triplicate groups of fish in each study. In the first study, weight gain, feed efficiency (FE), protein efficiency ratio (PER), and protein retention (PR) were not significantly different in fish fed either Westar or GT200 at any level of substitution. Fish fed GT73 exhibited a gradual reduction in weight gain, FE, and PER as the level of GTC increased. However, the only significant reduction was in weight gain of fish fed 20% GT73 as compared to fish fed 5% GT73. Because of an error in preparing samples prior to the experiment, samples GT200 and GT73 were essentially equivalent in composition. The differences were explained by differences in processing temperatures that occurred after the sample mixing error occurred. In the second study, mean weight gain, PR, and survival were not significantly different among forms of canola. FE and PER values were significantly lower in fish fed 15% Westar as compared to fish fed 10% Westar; other FE and PER values were not significantly different. On the basis of these results, GTC processed into a toasted meal and incorporated into diets for rainbow trout is equivalent to a parental line of canola.     

Nitrogen Fertilization Influences Protein Nutritional Quality in Red Head Chicory

ABSTRACT

Excess nitrogen fertilization of leafy vegetables may cause undesirable accumulation of nitrates and a decrease in essential amino acids, resulting in a decrease in protein nutritional quality. We investigated the effect of nitrogen (N) fertilization (0, 100 or 200 kg N ha^?1) on the nutritional quality of red head chicory proteins. Lysine limited biological value of proteins in the control (0 N) as well as fertilized samples. The lysine content and protein biological value according to Mitchell and Block method decreased significantly (p ≤ 0.05) with 100 and 200 kg ha^?1 nitrogen applied relative to control. The Oser's essential amino acid index and protein biological value were relatively high and did not decrease with increased N fertilization. The correlation between the protein biological value of red head chicory and crude protein levels was negative (p < 0.001). Protein nutritional quality was optimal for adults and lower than optimal for children aged 2–5 and 10–12 years.     

日粮蛋白水平对生长猪生产性能和氮平衡的影响

通过氮平衡试验和饲养试验,研究日粮不同蛋白水平(18.2%、16.5%、15.5%、14.5%和13.6%)对生长猪生产性能和氮平衡的影响。结果表明,粪氮、尿氮、总氮、氮吸收和氮沉积均随日粮蛋白水平的降低而降低(P<0.05);日粮蛋白水平显著影响了猪的生产性能、眼肌面积、血清尿素氮和血浆游离必需氨基酸浓度(P<0.05);在低蛋白日粮中添加赖氨酸、蛋氨酸和苏氨酸,可使生长猪日粮蛋白水平从18.2%降至14.5%,且大幅度降低氮排泄量而不影响其生产性能;当日粮蛋白水平降低4个百分点以上时,赖氨酸、蛋氨酸和苏氨酸均能够满足生长猪生长需要,但异亮氨酸、缬氨酸和精氨酸等必需氨基酸及酪氨酸和丝氨酸等非必需氨基酸则不能满足其生长需要。     

Retention of essential amino acids during extrusion of protein and reducing sugars

This research investigates the retention of essential amino acid profiles of products during the extrusion of proteins and reducing sugars. Animal proteins (egg and milk protein at 10 and 30% levels) and reducing sugars (fructose and galactose at 0, 2, and 8% levels), with pregelatinized wheat flour, were extruded at 110 and 125 degrees C product temperatures and feed moistures of 19 and 23.5% for egg protein and 13.75 and 16% for milk protein. The nutritional property analyzed was essential amino acid retention, and sugar retention was also considered to understand the relationship of sugars with retention of amino acids. Lysine showed the lowest retention (up to 40%) of all the essential amino acids. Retention of other essential amino acids varied from 80 to 100% in most situations. Apart from lysine, tryptophan, threonine, and methionine were found to be significantly changed ( P < 0.05) with processing conditions. Increased protein and sugar levels resulted in a significant degradation of lysine. Greater lysine retention was found at a lower temperature and higher feed moisture. Results of sugar retention also showed similar patterns. The products made from fructose had greater lysine retention than products made from galactose with any type of protein. The outcomes of this research suggested that the combination of milk protein and fructose at a lower temperature and higher feed moisture is most favorable for developing high-protein extruded products.     

Chlorogenic acid moderately decreases the quality of whey proteins in rats

During processing and storage, phenolic compounds (PCs) may react with food protein bound amino acids (AAs). Such reactions have been reported to change physicochemical and to decrease in vitro digestion properties of proteins. A rat growth and nitrogen (N) balance study was conducted to prove whether derivatization with chlorogenic acid (CA) affects the nutritional quality of beta-lactoglobulin (beta-LG). Test diets (10% protein level) contained nonderivatized beta-LG (LG, treated under omission of CA), low derivatization level beta-LG (LGL), high derivatization level beta-LG (LGH), or casein supplemented with l-methionine (0.3% of diet; C+met) as an internal standard. An additional group received untreated beta-LG supplemented with pure CA (1.03% of diet; LG+CA). The AA composition of test proteins, plasma AAs, and liver glutathione (GSH) concentrations were determined. Protein digestibility-corrected amino acid score (PDCAAS) was calculated using human or rat AA requirement patterns and rat fecal digestibility values. N excretion was significantly higher in feces and lower in urine of rats fed with LGH as compared to LG and LGL. Consequently, true N digestibility (TND) was significantly lower with LGH as compared to LG and LGL. The lower content of methionine, cysteine, lysine, and tryptophan in LGH corresponded to a reduced TND. Net protein utilization (NPU) was not different between treated beta-LG fed diet groups but was lower than in LG+CA and C+met fed groups. Only at a relatively high level of derivatization with CA, the otherwise good nutritional quality of beta-LG is affected so that TND is reduced, while NPU still remains unaffected. Derivatization of beta-LG with CA does not seem to lead to an additional deficiency in a specific indispensable AA in growing rats fed with 10% protein.