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51.

Background

This study was conducted to evaluate the apparent metabolizable energy (AME) and true metabolizable energy (TME) contents in 30 sources of corn distillers dried grains with solubles (DDGS) in adult roosters, and establish the prediction equations to estimate the AME and TME value based on its chemical composition and color score.

Methods

Twenty-eight sources of corn DDGS made from several processing plants in 11 provinces of China and others imported from the United States. DDGS were analyzed for their metabolizable energy (ME) contents, measured for color score and chemical composition (crude protein, crude fat, ash, neutral detergent fiber, acid detergent fiber), to predict the equation of ME in DDGS. A precision-fed rooster assay was used, each DDGS sample was tube fed (50 g) to adult roosters. The experiment was conducted as a randomized incomplete block design with 3 periods. Ninety-five adult roosters were used in each period, with 90 being fed the DDGS samples and 5 being fasted to estimate basal endogenous energy losses.

Results

Results showed that the AME ranged from 5.93 to 12.19 MJ/kg, TME ranged from 7.28 to 13.54 MJ/kg. Correlations were found between ME and ash content (-0.64, P < 0.01) and between ME and yellowness score (0.39, P < 0.05) of the DDGS samples. Furthermore, the best-fit regression equation for AME content of DDGS based on chemical composition and color score was AME = 6.57111 + 0.51475 GE - 0.10003 NDF + 0.13380 ADF + 0.07057 fat - 0.57029 ash - 0.02437 L (R2 = 0.70). The best-fit regression equation for TME content of DDGS was TME = 7.92283 + 0.51475 GE - 0.10003 NDF + 0.13380 ADF + 0.07057 fat - 0.57029 ash - 0.02437 L (R2 = 0.70).

Conclusions

This experiment suggested that measuring the chemical composition and color score of a corn DDGS sample may provide a quality parameter for identifying corn DDGS sources energy digestibility and metabolizable energy content.  相似文献   
52.
Transformations of nitrogen (N) from poultry litter (PL), dairy manure compost (DMC), anaerobically digested fiber (ADF), Perfect Blend 7–2–2 (PB), a compost/litter mixture (C/L), dried distillers grains from ethanol production (DG), and mustard meal from biodiesel production (MM) applied to a Quincy fine sand were investigated in an incubation experiment over 210 days. The cumulative release totals of available N after 210 days were 61, 61, 56, 44, 29, 2, and –2% for the total N in MM, PB, DG, PL, C/L, DMC, and ADF, respectively. With application of MM and DG, ammonium (NH4-N) accumulated initially in the soil with very little nitrification, possibly because of inhibition of nitrification related to chemical compounds in the amendments. Mineralization of organic N to NH4-N and nitrate (NO3-N) was relatively slow from MM- and DG-amended soils, indicating the potential for using biofuel by-products as slow-release N sources for plants.  相似文献   
53.
54.
The objective of this experiment was to determine the standardized ileal digestibility(SID) of amino acids(AA) in 3sources of distillers dried grains with solubles(DDGS) with different concentrations of fat.Twelve growing barrows(initial body weight:76.1 ± 6.2 kg) were randomly allotted to a replicated 6×4 Youden square design with 6 diets and 4 periods.The fat content of the 3 sources of DDGS were 11.5,7.5,and 6.9%respectively.Diets contained 60%DDGS and fat concentration of the diets were 7.5,52,and 5.2%,respectively.Two additional diets containing the 2sources of DDGS with 75 and 6.9%fat were also formulated,and corn oil was added to these diets to increase the concentration of fat in the diets to levels that were calculated to be similar to the diet containing conventional DDGS with 11.5%fat.A N-free diet was also formulated to calculate endogenous losses of crude protein(CP) and AA from the pigs.Pigs were fed experimental diets during four 7-d periods.The first 5 d of each period were an adaptation period and ileal digesta were collected on d 6 and 7 of each period.The apparent ileal digestibililty(AID) and SID of CP and all indispensable AA,except AID Pro and SID of Trp,were greater(P 〈 0.01) in conventional DDGS than in the 2 sources of DDGS with reduced fat.Adding oil to the diets containing the 2 sources of DDGS with reduced fat did not consistently increase SID of AA.In conclusion,conventional DDGS has greater SID values for most AA compared with DDGS that contains less fat and inclusion of additional oil to diets containing low-fat DDGS does not increase AID or SID of AA.The lower AA digestibility in low-fat DDGS could not be overcome by the inclusion of additional fat to the diets.  相似文献   
55.
The effects of replacing corn and soybean meal with distiller's dried grains and solubles in the weanling horse diet were examined. Sixteen weanling horses, 12 fillies and four colts, were fed completely pelleted diets consisting of 50% alfalfa in addition to 50% of a concentrate containing either corn and soybean meal (CS), or 30% of the concentrate replaced with distiller's dried grains with solubles (DDGS). There were no significant differences (P > .05) between the two diets in either average daily gain or gain-to-feed ratio. The CS diet had a higher apparent dry matter digestibility (P < .0001), and higher apparent digestibility of crude protein (CP), acid detergent fiber (ADF), and neutral detergent fiber (NDF) (P < .01). It was concluded that replacing a portion of the corn and soybean meal with distiller's dried grains with solubles in the weanling horse diet did not lead to significant growth depression. However, the diet containing DDGS had reduced apparent digestibility of dry matter, CP, and fiber. Therefore, it was concluded that it may not be advisable to replace more than 30% of the concentrate portion or 15% of the total diet with distiller's dried grains and solubles when alfalfa is used as the forage source constituting 50% of the weanling diet. Even less DDGS may be desirable to substitute for corn and soybean meal in weanling horse diets if the forage source is one with lower protein quality than alfalfa. It is possible that using DDGS for less than 30% of the concentrate portion of the diet along with high-quality alfalfa forage may produce comparable gain and feed efficiency results with less depression of apparent digestibility of dry matter, crude protein, and fiber.  相似文献   
56.
本试验旨在优化白地霉、米曲霉、绿色木霉和枯草芽孢杆菌混菌固态发酵白酒糟开发为蛋白质饲料的条件,并评定其营养价值。将白地霉、米曲霉、绿色木霉和枯草芽孢杆菌按照1∶1∶1∶1混合后按10%接种到培养基中,采用L16(54)正交试验设计,共5个发酵条件,分别为基料、尿素、磷酸二氢钾、p H、水分,每个条件4个变量,共16组发酵条件。按条件配制好的混合物放置于(30±2)℃中培养72 h。对发酵前后真蛋白质、粗纤维含量进行极差分析确定最优条件,再比较最优条件发酵前后白酒糟营养水平和氨基酸组成的变化。结果显示:1)基料按照80%白酒糟、10%麸皮、5%玉米粉、5%菜籽粕配比,尿素添加量为1.5%,磷酸二氢钾添加量为0.7%,p H为5、水分为50%时发酵效果最好,为最优发酵条件。2)最优条件下发酵后白酒糟与发酵前相比,真蛋白质含量提高了57.85%(P0.01);粗纤维、酸性洗涤纤维、中性洗涤纤维、粗脂肪含量分别降低了42.39%、31.95%、27.73%、21.48%(P0.01);钙、磷含量分别提高了16.67%和68.18%(P0.01);总氨基酸含量提高了24.47%,其中赖氨酸、蛋氨酸、苏氨酸、缬氨酸、亮氨酸、异亮氨酸和脯氨酸含量分别提高了109.68%、38.09%、39.39%、71.43%、28.93%、10.87%和3.70%。综上可得,利用白地霉、米曲霉、绿色木霉和枯草芽孢杆菌混菌发酵白酒糟的最佳条件是:基料组成80%白酒糟、10%麸皮、5%玉米粉、5%菜籽粕,尿素1.5%,磷酸二氢钾0.7%,p H 5,水分50%,发酵产物的真蛋白质含量为24.34%。  相似文献   
57.
Feeding high levels (≥40% dry matter) of distillers grains may increase the risk for cattle to carry enterohemorrhagic Escherichia coli (EHEC) O157. The mechanism for the increased risk is not known nor whether non‐O157 EHEC are similarly affected. Our objective was to test whether the fibre content or other components of modified distillers grains plus solubles (MDGS) affects the probability for cattle to carry EHEC serogroups of public health importance. A 2 × 2 plus 1 factorial treatment arrangement within a randomized block design was utilized. Within each of four blocks, 25 feedlot pens (n = 8 steers/pen) were assigned randomly to (i) corn‐based control diet; (ii) 20% dry matter (DM) MDGS; (iii) 40% DM MDGS; (iv) corn bran added to corn‐based diet to match fibre of 20% MDGS or (v) 40% MDGS. Rectoanal mucosa swabs (RAMS) were collected on day (d)0, d35, d70 and d105; hide swabs were collected on the last feeding day. Samples were tested for EHEC by a molecular screening assay. The effects of fibre source and fibre level on EHEC carriage were tested using multilevel logistic regression (generalized linear mixed models; α = 0.05). EHEC O45 RAMS detection was associated with fibre level, source and sampling day. EHEC O103 RAMS detection increased by feeding 40% MDGS but not the corresponding corn bran diet. Hide contamination by EHEC O45 or O103 was less likely in cattle fed MDGS compared to corn bran diets. EHEC O111 RAMS detection decreased by feeding 40% MDGS but not by feeding the corresponding corn bran diet. Detection of EHEC O157 or O145 was not associated with dietary factors. Feeding 40% MDGS increased the probability for carriage of some EHEC serogroups but decreased probability of others, which indicated that EHEC serogroups have different risk factors associated with feeding MDGS and little association with dietary fibre.  相似文献   
58.
59.
综述了国外关于肉牛非常规饲料资源开发的文献报道,主要介绍了食品加工副产品和工业副产品作为肉牛饲料原料的研究进展,并对其研究结果进行总结分析,以期为我国肉牛产业的快速发展提供借鉴。  相似文献   
60.
A feeding trial was performed to investigate inclusion levels of distillers dried grains with solubles (DDGS) as a fishmeal replacement for juvenile Nile tilapia (Oreochromis niloticus). On a dry matter basis, five isocaloric [19.3 ± 0.4 kJ/g (mean ± SE)], isonitrogenous (39.1 ± 0.5% crude protein) diets were formulated to contain 17.5%, 20%, 22.5%, 25%, and 27.5% DDGS and compared against a 0% DDGS, reference diet (gross energy = 14.5 kJ/g; crude protein = 39.8%). The reference diet resulted in significantly higher body weight gain (BWG), food conversion ratio (FCR), and protein efficiency ratio (PER) than experimental diets except that 17.5% DDGS provided similar FCR and PER. The diet containing 27.5% DDGS had significantly lower FCR and PER values than all other diets even though apparent digestibility did not significantly differ among experimental diets. Although DDGS can be incorporated at higher levels, 20% DDGS provided the highest apparent BWG among experimental diets, while 17.5% promoted the best FCR and PER. Fishmeal may be replaced with low levels of fuel‐based DDGS to reduce feeding cost; however, additional supplements should be considered to enhance fish performance.  相似文献   
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