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1.
Measurement of gas produced during in-vitro fermentation was used to assess the ferment ability of urea treated and untreated finger millet straw to Which various levels of concentrate (maize/wheat bran/groundnut cake 35:32: 30) had been added. Data obtained from this technique were compared with in-vitro digestibility data obtained earlier on the same feeds. Similar trends for the effect of supplementation on digestibility were observed in both in-vitro and in-vivo measurements. Linear correlation equations were obtained between gas produced and the proportion of dry matter disappearing, enabling in-vitro gas production to be expressed in in-vitro digestibility's. A single pool exponential equation was fitted to the gas production data enabling estimates to be made of the time when in-vitro digestibility's best matched in-vivo digestibility data. These times were 45.8 and 47.9 h of untreated straw, 43.5 and 61.0 h for treated straw for trials 1 and 2, respectively. Statistically significant (P < 0.05) interactive effects between supplement and both treated and untreated straws were observed. The digestibility of untreated straw was particularly stimulated by small quantities of supplement. The digestibility of treated straw was higher than that of untreated straw and less stimulated by supplementation. These findings are consistent with the hypothesis that fibre digestibility can be increased by providing a supplement which provides sufficient nutrients to stimulate the activity of rumen micro organisms.  相似文献   

2.
Chaffed wheat straw treated with urea (5% wt/wt) alone or with rumen liquor, a source of urease (EC 3.5.1.5), was stored in polythene bags at 4, 22, and 37 degrees C up to 60 d. Moisture concentration was adjusted to 40%. Urea remaining in the straw and ammonia concentrations in the bags were measured on 2, 4, 8, 12, 16, 25, 40 and 60 d. Urea hydrolysis increased exponentially with time. Hydrolysis of urea was highest at 22 degrees C followed by 37 and 4 degrees C. Addition of rumen liquor substantially increased rate of urea hydrolysis at all temperatures studied, suggesting that treatment time can be reduced by addition of rumen liquor. Rates of ammonia binding at different temperatures were in the order 22 degrees C greater than 37 degrees C greater than 4 degrees C. No hydrolysis of urea was observed up to 7 d of storage at 22 and 37 degrees C when straw was autoclaved and the treatment was carried out under aseptic conditions.  相似文献   

3.
BACKGROUND: The present study investigated the effect of garlic powder (GAP) supplementation on rumen fermentation pattern, nutrient digestibility and intake in ruminants fed on straw as a roughage source. RESULTS: Dry matter intake and apparent digestibility of nutrients were similar among treatments. The apparent digestibility of crude protein tended to be higher in cattle supplemented with GAP compared to those fed without GAP (P = 0.08). Ruminal populations of protozoa and bacteria were decreased, as influenced by GAP supplementation. Ruminal pH and NH3‐N were similar among treatments, while blood urea nitrogen tended to be decreased (P < 0.05). Total volatile fatty acids (VFAs) were not affected by GAP supplementation but individual VFAs were significantly different (P < 0.05), especially C3; meanwhile, C2:C3 ratio was reduced by GAP supplementation (P < 0.05). In addition, N balances were significantly increased as level of GAP supplementation increased and was highest at 120 g d?1 GAP. CONCLUSION: Results of this study suggest that feeding of GAP at 80 g d?1 with urea‐treated rice straw could enhance ruminal propionate production and thus lower C2:C3 ratio, decreasing the protozoal population, as well as increasing N retention and absorption in ruminants. Copyright © 2008 Society of Chemical Industry  相似文献   

4.
Nigerian processed cottonseed meal was substituted for 0, 25, 50, 75 and 100 % portions of dietary groundnut cake on an equi-protein basis. The diets were fed to 50 Large White and Large White × Landrace crossbed pigs from 13.9 kg average weight to 70 kg liveweight in a bi-replicate single-way classification trial. Average daily gain and average daily feed consumption were 0.51, 0.52, 0.53, 0.55 and 0.56 kg; and 1.67, 1.77, 1.85, 1.84 and 1.82 kg for the respective diets. Feed/gain ratios ranged from 3.25 to 3.49. No significant differences between diets were seen for either of these parameters. Neither the gross tissue nor the jointed carcass proportions were significantly affected by cottonseed meal substitutions. The mean fresh weights of the liver and lungs decreased with increasing levels of dietary cottonseed meal but the differences were not significant. None of the pigs showed symptoms of gossypol intoxication. The data suggest that some of the Nigerian-processed cottonseed meals can be combined in various proportions with groundnut cake to supply protein, or used singly, up to 20 %, in diets for weaner-grower pigs.  相似文献   

5.
In Experiment I a Latin square design was used to study the utilization of urea nitrogen adsorbed on flaked soybean hulls in normal rations of high producing dairy cows. Concentrates containing urea, urea with supplemental minerals, or soybean meal as the protein supplement were fed with corn silage and alfalfa in a total ration of approximately 17% crude protein. Both urea concentrates contained 2.7% urea. Animals fed urea and soybean had similar milk yields (28.7 and 27.9 kg/day), milk protein, and digestible dry matter intakes. Urea with mineral produced lower milk yield (25.3 kg/day), milk protein, and dry matter intakes, probably because of excessive mineral content. Urea nitrogen of plasma was similar for all three diets. Essential amino acids of plasma were lower for urea than for soybean while for urea mineral the essential amino acids were midway between the other two. In Experiment 2 a switchback design was used to compare the urea-soybean hull concentrate diet of Experiment 1 (17% crude protein) to a negative control diet consisting of its basal components without urea adjusted to 12% protein with wheat bran. Milk yield was 1.2 kg/day higher when the urea diet was fed. Perhaps due to improved urea distribution in the rumen, flaked soybean hulls with urea were effective in maintaining the feed intake necessary for high milk production.  相似文献   

6.
The effect of several variables on the in vitro permeation of urea through hairless mouse skin has been studied in order to determine the causes of an increasing permeability phenomenon found in studies with a range of hydrophilic compounds.
The permeation of urea increased for a period of approximately 100 h after which a steady state permeation pattern was observed for approximately 25 h. Urea did not effect its own permeation in concentrations between 0.01 M and 1.67 M, and the same pattern of increasing permeation was followed in the presence of ( N -morpholine)propanesulphonic acid and tris(hydroxyme)amino-methane buffers, as in the presence of normal saline. Urea did not affect the permeation of tritiated water. Methanol and water exhibited the same pattern of increasing permeation as urea.
The continuously increasing permeation rate of urea up to 100 h is believed to be due to penetration and extensive association of water with the components of the stratum corneum, altering the ultra-structure of the stratum corneum and leading to the formation of large and extensive hydrophilic diffusion channels which do not exist in fresh, untreated skin. These presumed channels open the stratum corneum to facile permeation of highly polar substances such as urea. The physical events leading up to the ultra structural changes within the tissue at the microscopic level remain obscure and are the subject of ongoing research.
L'absorption percutanée de l'urée  相似文献   

7.
Twelve species of toxigenic and zoopathogenic fungi were isolated from three major types of the Nigerian groundnut cake snacks. All the isolates grew well on groundnut cake infusion medium and induced changes in the oil (decrease) and free fatty acid (increase) contents of groundnut seed medium with time. The largest changes were induced by Aspergillus flavus, A. niger and A. fumigatus. Mould deterioration of groundnut cake snack samples kept under traditional, “industrial” and retailer's storage methods was studied. Mouldiness was first recorded on the 5th day for samples stored under the retailer's method and on the 10th day for samples from other storage methods. The odour and taste acceptability values, although partly affected by the different storage techniques decreased rapidly with storage period. The overall results suggest the need for research into the processing and packaging to extend the shelf life of the snacks.  相似文献   

8.
Four steers were given diets of straw and tapioca supplemented with urea, casein, formaldehyde treated casein (FTC), decorticated groundnut meal (DCGM), soya bean meal (SBM), maize gluten meal (MGM) or fish meal (FM) to determine the effect of degradability on rumen amino acid and peptide concentrations. Maximum concentrations of amino acid and peptide-N in rumen ultrafiltrates occurred 1 h after feeding. Total amino acid-N concentrations (mg litre?1) at this time were low, ranging from 1.2 SE 0.8 (urea) to 15.6 SE 6.0 (casein) with little variation in individual amino acids. The peptide-N concentrations (mg litre?1) were higher, ranging from 2.4 SE 0.5 (urea) to 160.0 SE 21.0 (casein), but were poorly correlated with degradability and solubility. Apart from casein, the highest concentrations of peptide-N were for those protein supplements, MGM (136.0 SE 25.0), FM (90.0 SE 15.0), and FTC (87.0 SE 14.0), with the lowest degradability suggesting that other factors, such as hydrophobicity, are also involved in the control of rumen peptide concentrations. Pooled samples taken 1 h after the morning feed were separated into three molecular weight (MW) fractions, 5000–50 000 da, 250–5000 da and < 250 da by gel filtration chromatography. From amino acid analysis it was found that the highest proportion of peptide-N was in the 250–5000 da fraction, and although some high MW (5000–50 000) constituents were present, only the FTC and MGM diets gave rise to significant amounts.  相似文献   

9.
研究过氧化尿素的制备及生产母液的循环利用情况,对过氧化尿素用于纺织品漂白时的浓度、时间、pH值等工艺条件进行筛选。过氧化尿素作漂白剂利用率高,无腐蚀性,漂白工艺简单,时间短,溶液可反复使用,节约能源,且综合成本低,漂白产品质量能达到相应标准。  相似文献   

10.
From 1998 to 2001, 216 ingredients intended for incorporation into chicken feed, which included groundnut cake, maize, millets, rice bran, sorghum, soybean, sunflower, and mixed feeds, were assayed for aflatoxins and ochratoxin A contamination using an indirect competitive enzyme-linked immunosorbent assay. Thirty-eight percent of the samples were contaminated with aflatoxins and 6% with ochratoxin A. The incidence scores of aflatoxin contamination in excess of 10 microg/kg were 41 of 95 for maize, 18 of 30 for mixed feeds, 10 of 37 for groundnut, 6 of 29 for sorghum, 5 of 10 for sunflower, 3 of 14 for rice bran, and 1 of 8 for millet. Ochratoxin A contamination, in excess of 10 microg/kg, was found in 9 of 29 sorghum samples, 1 of 27 groundnut samples, 1 of 14 rice bran samples, 1 of 10 sunflower samples, and 2 of 8 millet samples. Ochratoxin A was not found in maize and mixed feeds. None of the three soybean samples contained ochratoxin A. This is the first report, to our knowledge, of co-occurrence of aflatoxins and ochratoxin A in Indian poultry feeds. The results confirm the importance of analysis of ingredients before incorporating them into mixed feeds.  相似文献   

11.
Nutritive value of high moisture alfalfa hay preserved with urea   总被引:3,自引:0,他引:3  
Urea (2 and 4%) was added to high moisture hays and compared with untreated wet or dry hays. Means for bale temperatures (degree C) for 1 wk postharvest were highest for wet control (41.2), lowest for dry control (31.4), and intermediate for urea treatments (36.7). By 4 wk postharvest, all temperatures were equal. Protection from molding was most effective for 4% urea, and 2% urea was superior to wet control. By 4 mo postharvest, CP for low urea had decreased due to NH3 loss, and CP for wet control had increased due to DM loss, so they were not different. Initially, ADF was similar for the hays, but after 4 mo storage the wet control was highest (41.7%), the dry control lowest (36.0%), and urea treatments intermediate. Lignin and NDF followed similar trends. In vitro DM digestibilities were highest for the wet control at harvest but lowest at 120 d with high urea and dry control greater than low urea. Feed intakes and milk yields in lactating cows fed the hays were not different. These data show that addition of 2 or 4% urea improved quality of hay baled at about 25% moisture; high urea was more effective than low urea.  相似文献   

12.
Thirty-six lactating Holstein cows were in a 5 × 3 factorial partially balanced incomplete block design with three missing categories to study effects of different forms of cottonseed hulls and liquid supplements on milk production and composition. Roughages were regular cottonseed hulls, pelleted cottonseed hulls, pelleted cottonseed hulls with 9% fat, pelleted undelinted cottonseed hulls, and pelleted undelinted cottonseed hulls with 9% fat. Liquid supplements were 8% Masonex2 (hemicellulose extract) and 8% cane molasses. Control had no supplement. All rations were adjusted to contain 30% cottonseed hulls. Roughages with added fat gave total rations of 2.5% added fat (air dry).Least square means for daily intake of dry matter, milk yield, and fat percent were regular cottonseed hulls 21.6 kg, 20.3 kg, 3.37%; pelleted cottonseed hulls 20.3 kg, 21.4 kg, 3.06%; pelleted cottonseed hulls plus fat 20.1 kg, 21.2 kg, 2.51%; pelleted undelinted cottonseed plus fat 19.4 kg, 20.9 kg, 2.73%. Pelleted cottonseed hulls increased milk yield, decreased dry matter intake and milk fat percent, but did not affect milk fat yields. Rations with pelleted undelinted cottonseed hulls resulted in higher milk fat percent and body weight than pelleted cottonseed hulls. Added fat decreased milk fat percent and yield because of high degree of unsaturation. Liquid treatments produced no detectable effects on dry matter intake, milk yield, or fat percent.  相似文献   

13.
Wheat (Triticum aestivum L) straw and corn (Zea mays L) silage were extruded under variable conditions of temperature and screw speed. The resulting extrudates were then tested for their fermentability according to cumulative production of gas, and compared with each other and with the untreated material. VFA analysis was carried out at the end of fermentation, to assess the pattern of fermentation. Analysis of the cumulative gas curves showed significant differences between substrates. Extrusion treatment also led to significant differences, though the effect of screw speed and temperature were not always consistent. However, most differences in cumulative gas production were negative, particularly for wheat straw, which suggests that, under the conditions used, extrusion actually reduced the fermentability of the fibres. © 1997 SCI.  相似文献   

14.
This study was conducted to assess major Aspergillus species and aflatoxins associated with groundnut seeds and cake in Eastern Ethiopia and evaluate growers’ management practices. A total of 160 groundnut seed samples from farmers’ stores and 50 groundnut cake samples from cafe and restaurants were collected. Fungal isolation was done from groundnut seed samples. Aspergillus flavus was the dominant species followed by Aspergillus parasiticus. Aflatoxin analyses of groundnut seed samples were performed using ultra performance liquid chromatography; 22.5% and 41.3% of samples were positive, with total aflatoxin concentrations of 786 and 3135 ng g?1 from 2013/2014 and 2014/2015 samples, respectively. The level of specific aflatoxin concentration varied between 0.1 and 2526 ng g?1 for B2 and B1, respectively. Among contaminated samples of groundnut cake, 68% exhibited aflatoxin concentration below 20 ng g?1, while as high as 158 ng g?1 aflatoxin B1 was recorded. The study confirms high contamination of groundnut products in East Ethiopia.  相似文献   

15.
The effect of gossypol content of cottonseed cake given as a source of CP in lamb (n = 8) rations was examined on the following blood parameters: plasma total protein, albumin, globulins, urea, glucose, hematocrit, hemoglobin, and mean corpuscular hemoglobin concentrations. The diets were isonitrogenous and isocaloric and contained 0, 15, and 30% cottonseed cake for 62 d. Blood samples were taken at the beginning, middle, and end of the experiment. Plasma total protein and globulins were higher at d 30 of the experimental period, but plasma albumin concentration, hematocrit, and hemoglobin were higher at the beginning of the experiment; plasma urea concentration was higher at d 60, and plasma glucose concentration was lower at d 30 of the experiment. The highest fraction in all treatments was albumin, followed by alpha 2-globulin and beta-globulin fractions, and there was no gamma 1-globulin fraction at d 30 and 60 of the experimental period. Liver examination showed significant differences in free gossypol content and accumulation, total N, and total protein percentage among the three treatments. Gossypol toxicity was not observed. The absence of gossypol toxicity in these animals has been attributed to detoxification of free gossypol by the formation of gossypol-protein complex in the rumen.  相似文献   

16.
The effect of cellulose crystallinity on in vitro digestibility (IVD) and fermentation kinetics was investigated in samples of meadow hay and barley, wheat and rice straws. A saturated solution of potassium permanganate was used to isolate the celluloses, and their crystallinity was evaluated in a Fourier transform infrared spectrometer as the ratio of the observed transmittance at two distinct wave frequencies . IVD was determined after 48 h of incubation, and the kinetics of fermentation was studied with fully automated gas production equipment. Despite significant differences (P < 0.05), crystallinity showed low variation (0.30–0.42) among celluloses and correlated positively with IVD (P < 0.05). Although positively correlated with maximal gas production (r = 0.91) and rates of fermentation, IVD (averaging 784 g kg?1 organic matter (OM)) was also low for all samples as compared with the usually referred values for isolated celluloses. The lowest means were observed for meadow hay and rice straw. The cumulative gas production profiles were well described by a monophasic model (r2 = 0.997, RSD (residual standard deviation) = 8.367), but all the curves had a lag phase varying from 3 to 6 h. Cellulose isolated from rice straw showed the lowest maximal gas production (366 ml g?1 OM) and highest times to reach half of the maximal gas production and maximal rate. Transmission electron microscopy (TEM) of two cellulose samples showing considerable gas production at highest rates as compared with cellulose isolated from rice straw that provided the lowest gas production at the lowest rate revealed generalised bacterial colonisation, the presence of glycocalyx fibres and cell erosion in all samples. Although samples collected after 12 h of fermentation appeared to present lower microbial attack as compared with those incubated for 24 h, TEM did not explain the observed differences in the data. Since crystallinity, IVD, gas production and rates of fermentation were shown to be associated with the nutritional availability of cellulose, further research dealing with extreme values of cellulose crystallinity may be important. © 2003 Society of Chemical Industry  相似文献   

17.
This study evaluated the differences in the gas produced by Sesbania accessions and related gas production to macro-constituents and tannin content of the browse species. Fresh samples were incubated in triplicate (about 200 mg per syringe) in a medium prepared from sieved rumen liquor harvested from two rumen-fistuiated cows fed native pasture hay ad libitum and 2.0 kg cottonseed cake per head per day. Sesbania species had similar rates of gas production but differed (P < 0.001) in the volume of gas produced. The ranking order for gas production was S grandiflora > S sesban > S keniensis > S goetzei. There was little variation in the gas production parameters within S grandiflora and S goetzei. But the variation was large within S sesban. Regression analysis showed that the rate of gas production was negatively affected (P < 0.025) by the lignin content of the browses, but the volume of gas produced was negatively related to the neutral detergent fibre, hemicellulose, lignin and insoluble proanthocyanidins content of browses. Ouster analysis showed a broad agreement between gas production constants, macro-constituents and tannin contents in classifying accessions into high or low nutritive value groups.  相似文献   

18.
The role of oyster shell as calcium supplement in the utilization of gossypol-containing cottonseed cake (CSC) was assessed using Hypeco broiler chickens. The results showed that of the organ measured, only the relative weight of the spleen was significantly (P less than 0.05) decreased by oyster shell supplementation in the CSC diets. Spleen weight correlated negatively (r = -0.45) with dietary calcium. Alkaline phosphatase activity in the liver was significantly (P less than 0.05) increased due to the levels of oyster shell supplemented while the activities of serum and liver alanine aminotransferase and aspartate aminotransferase were not significantly influenced. The results also showed that although oyster shell supplementation generally increased alkaline phosphatase activity, bone mineralization was relatively uninfluenced as judged by the low coefficients of variation (CV) of 3.14-3.51% and 3.39-4.82% for calcium and phosphorus content in the femur and tibia respectively.  相似文献   

19.
V A Aletor  O E Onibi 《Die Nahrung》1990,34(4):311-318
The comparative utilization of cottonseed cake (CSC) diet supplemented with varying levels of oyster shell (0.00, 1.50, 3.00 and 4.50%) as a source of calcium, and groundnut cake (GNC) based diet were evaluated in a feeding trial using 100 day-old HYPECO broiler-chicks. The response criteria included performance, carcass traits and economics of production. The weight gains at the end of the trial were not significantly different. However, feed consumption significantly (P less than 0.5) increased with increasing dietary calcium. Feed consumption was significantly (P less than 0.05) correlated with dietary calcium levels with r = 0.96. Feed efficiency and protein efficiency ratio were significantly (P less than 0.05) better in the GNC diets than CSC based diets in spite of the oyster shell supplementation of the latter. Both nitrogen retention and apparent nitrogen digestibility were not significantly influenced. The percent dressed weight, percent eviscerated weight and the relative weights of the thigh, drumstick, chest, back, head and belly fat were not significantly influenced by the dietary treatment. Only the relative weight of the shank was significantly (P less than 0.05) influenced. The cost-benefit analysis showed that although it was chapter to formulate CSC diets, profits were identical with GNC diets when fed to the chicks. It was suggested that CSC could be a good substitute for GNC because of the ready availability of the former. Dietary calcium of up to 1.82% was beneficial in the utilization of the CSC.  相似文献   

20.
The carbon dioxide contents of four oilseeds and their components have been determined using Warburg flasks by treatment with trichloroacetic acid and measurement of the released gas as barium carbonate. All the oilseeds contained carbon dioxide, with high contents in the hulls and kernels of castorseed and in the annular spaces of cottonseed and groundnut (and possibly castor). Isolated castor-and cotton-seed oils absorbed large quantities of the gas, but lost most of it in 2–6 h of exposure. Gassed groundnut and safflower oils when subsequently exposed to the atmosphere showed superior storage stability to untreated controls over long periods. Storage of oilseeds and oils under carbon dioxide appears advantageous.  相似文献   

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