摘要:

Native and two modified forms of soybean phosphatidylcholine were used to study the nutritional effect of their fatty acids for postlarvalPenaeus japonicus.Five semipurified and isolipidic diets were formulated using casein as a protein source. Three diets contained 1.5 % of different types of phosphatidylcholine (95 % purity), i.e. native soybean phosphatidylcholine, hydrogenated soybean phosphatidylcholine and 1‐acyl lyso soybean phosphatidylcholine, besides 1% of n‐3 highly unsaturated fatty acid formulated as triglycerides. Two negative control diets contained either triglycerides or ethyl esters as a source of n‐3 highly unsaturated fatty acids without phospholipid. The experiment was conducted during two successive phases of 20 d starting from 12‐d old postlarvae. Feeding the diet containing native soybean phosphatidylcholine resulted in significantly better growth and resistance to osmotic shock ofP. japonicuspostlarvae compared to the other diets. The total lipid content of the tissue was significantly increased by the supplementation of soybean phosphatidylcholine, whereas no significant difference was observed for the shrimp fed the modified phosphatidylcholine sources compared to the phosphatidylcholine‐free diet at the end of the experiment. Shrimp fed the diet containing soybean phosphatidylcholine exhibited a higher polar lipid fraction in the whole body total lipid mainly as a result of the increased proportion of phosphatidylcholine and to a lesser extent of phosphatidylinositol at the expense of free fatty acids, free sterols and sterol esters. The content of 20: 5n‐3, 22 : 6n‐3 and total n‐3 highly unsaturated fatty acids in the shrimp tissue were higher in shrimp fed the native soybean and hydrogenated soybean phosphatidylcholine diets compared to those fed the phosphatidylcholine‐free and 1‐acyl lyso soybean phosphatidyl‐choline‐based diets. The fatty acid profile of tissue phosphatidylethanolamine was more influenced by the type of dietary phosphatidylcholine than that of tissue phosphatidylcholine. In the absence of phospholipids in the diet, triglyceride fish oil and a mixture of ethyl ester concentrate arid coconut oil with similar n‐3 highly unsaturated fatty acids content were equivalent sources of n‐3 highly unsaturated fatty acids. The beneficial effects of dietary phospholipids may be due to a more efficient transport and utilization of dietary neutral lipids through a better lipid mobilization following absorption in the intestinal mucosa rather than due to a better emulsification of neutral lipid in the gut lumen. The functionality of phosphatidylcholine in the diet of postlarvalP. japonicusrequires the presence of unsaturated fatty acids and an intact fatty acid moiety.

ISSN:0003-942X    

DOI:10.1080/17450399809381901

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Hindgut fermentation differs from rumen fermentation by a lower methane production and the presence of reductive acetogenesis. Bile acids which are lost into the lower digestive tract may have a promoting effect on reductive acetogenesis in the hindgut. In this experiment it was investigated if bile acids induce reductive acetogenesis in rumen fermentationin vitro.Rumen contents from a fistulated cow were incubatedin vitrowith ground hay and increasing amounts of porcine bile acids or bile acid salts. Bile acids inhibited methane production up to 70 % of the control incubation. The concomitant increase in pro‐pionate production compensated for the lower methane production so that the 2H‐recoveries were in a normal range between 79–92 %.

ISSN:0003-942X    

DOI:10.1080/17450399809381902

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Faecal losses of phosphorus (P) were determined in 66 growing pigs weighing between 30 and 70 kg on a semi‐purified diet containing less than 1.3 g P/kg DM. Regression analysis showed that the coefficient of absorption of P from this diet was 82.5 % and that inevitable faecal P excretion of pigs fed this diet was, on average, 5.9 mg/kg BW.d‐1with no statistically significant effect of body weight on faecal P excretion within the range of body weight studied.

ISSN:0003-942X    

DOI:10.1080/17450399809381903

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Two long‐term individual feeding experiments (336 and 307 days) were carried out with 52 (experiment I; Black and White dairy cattle) and 22 (experiment II; Yellow cattle) growing bulls. Rations varied in P‐content. In experiment I straw: concentrate‐mixture (1:2.5) were fed, phosphorus content of rations amounted to 2, 3 or 4g/kg DM. In experiment II maize silage was fedad lib.supplemented with 2.4 kg concentrate per animal per day. P‐content of rations amounted to 3 and 4g/kg DM. Apparent digestibility of rations was determined during experiments. Blood samples were taken to analyse selected parameters of metabolism.

ISSN:0003-942X    

DOI:10.1080/17450399809381904

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The effect of different technical treatments of rapeseed on its feed value for broilers and laying hens was the object of the study. The technical treatments comprised different grinding procedures (whole seed, roller mill ‐ coarse and fine adjustment, flake mill) resulting in different average particle sizes of the ground seed and thermal treatments of flaked seed (hydrothermal treatment, micronizer, jet sploder). Each thermal treatment was carried out at two temperatures. A marked increase in the digestibility of organic matter and of the AMENcontent was observed as the average particle size of the seed was decreased to < 0.56 mm and was much more pronounced for the broilers. AMENcontents of 21.1 to 22 and 22.6 to 23 MJ/kg DM were observed at this particle sizes for broilers and hens, respectively. Thermal treatment of rapeseed improved the apparent crude fat digestibility slightly whereas the apparent crude protein digestibility tended to decrease especially at the higher temperatures. This resulted in inconsistent changes in the apparent digestibility of the organic matter and the AMENcontent. Only the treatment with hot air (jet sploder) seemed to have preferential effects on the feed value for both broilers and hens. For the thermal treatments AMENcontents ranged from 18.8 to 21.9 and 19.0 to 24.3 MJ/Kg DM for broilers and hens, respectively.

ISSN:0003-942X    

DOI:10.1080/17450399809381905

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

The effect of number of film layers was investigated in silages produced in wrapped big bales. The herbage used was difficult to ensile lucerne wilted to DM levels of 320–490 g/kg. Fermentation changed to a more homofermentative process as the number of film layers increased. An increasing number of film layers (4, 6, 8 or 10) also resulted in a notable decrease in moulds and yeasts. Four layers could not guarantee successful preservation in lucerne, and higher numbers of undesirable micro‐organisms were detected. Hard stalks damaged the first two film layers during wrapping in the bales. Effect of number of film layers was more important than effect of additives for inhibition of mould and yeast counts.

ISSN:0003-942X    

DOI:10.1080/17450399809381906

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Apparent and true metabolisable energy (ME) values, corrected for zero nitrogen retention, of lucerne and barley were compared in balance studies between young (six months old, 50 to 60 kg BW) and mature (30 months old, 110 to 120 kg BW) ostriches. Birds were housed in individual metabolism crates and excreta collection were performed over a five day period after an adaptation period of seven days. Apparent metabolisable energy, corrected for zero nitrogen retention, (AMEN) of 9.17±0.251 MJ/kg (lucerne) and 14.24+0.136 MJ/kg (barley) for young ostriches do not differ (P>0.05) from values of 8.97+0.226 MJ/kg (lucerne) and 14.21 +0.134 MJ/kg (barley) obtained for mature ostriches. Also no significant differences occurred between true metabolisable energy, corrected for zero nitrogen retention, (TMEN) values of 9.16+0.450 MJ/kg (lucerne) and 13.94+0.390 MJ/kg (barley) for young ostriches and 9.26+0.412 MJ/kg (lucerne) and 13.92+0.316 MJ/kg (barley) for mature ostriches. It is concluded that similar AME,, and TMENvalues of feedstuffs would be suitable in ostrich diet formulation for age groups older than six months.

ISSN:0003-942X    

DOI:10.1080/17450399809381907

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Bioenergetik und Stoffproduktion landwirtschaftlicher Nutztiere von Hans Bergner und Leonhard Hoffmann, Harwood Academic Publishers, Amsterdam ISBN: 3–7186 5809–7

ISSN:0003-942X    

DOI:10.1080/17450399809381908

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

ISSN:0003-942X    

DOI:10.1080/17450399809381900

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor