Nutritional Value Of Diets Research Articles

The Use Of Eyestalk Ablation In Nutrition Studies With American Lobsters (Homarus americanus)

ABSTRACTBilateral eyestalk ablation results in an accelerated growth rate in lobsters (Homarus americanus). Feeding trials were used to determine whether this accelerated growth rate resulted in a greater response of ablated lobsters to differences in nutritional values of diets. The value of using eyestalk ablated lobsters in nutrition studies was evaluated by comparing their molt, mortality and weight gain responses to dietary proteins (casein, soy bean protein and cod fish protein concentrate (FPC) and lipids (cod liver oil (CLO), corn oil (CO) and a 1:1 mixture of CLO and CO), with similar responses of control lobsters. Groups of ablated and control lobsters were fed frozen brine shrimp (FBS) for comparative purposes. The ablated lobsters showed a more rapid response to dietary differences than did the control lobsters. Casein proved to be the best dietary protein, followed by soybean, with FPC being the poorest. While CLO has been shown to be better than CO as a dietary lipid source, it appears that a 1:1 mixture of the two oils is better than either one alone. The growth, molt rate and survival of ablated lobsters fed FBS was significantly better than for those fed any of the artificial diets used in this study.

Factors affecting the nutritive value of the diet and the composition of rumen fluid of grazing sheep and cattle

The digestibility and nitrogen content of the diet and of the green fraction of the diet, and concentrations of individual volatile fatty acids in the rumen were measured in sheep and cattle grazing together on five Phalaris tuberosa pastures varying in forage availability. The sheep and cattle were aged 5 and 6 months respectively. Measurements were made at monthly intervals for 5 consecutive months during which animals were rotated between pastures. Measurements of forage availability, structure and composition were subjected to a principal components analysis from which orthogonal variables describing pasture composition were calculated. These were related to the nutritive value of the diet and the composition of rumen fluid by regression analysis. Diets selected by sheep were of higher digestibility and nitrogen content than those selected by cattle, because they contained more green material and the green material selected by the sheep was of higher digestibility and nitrogen content. The nutritive value of the diet of sheep varied with the availability of green forage, and that of cattle with both the availability of green and the bulk of forage on offer. Cattle were the more sensitive to changes in the quantity of green material available, and differences between sheep and cattle in the nutritive value of diets were reduced as the quantity of green material and the bulk of forage increased. The rumen liquor of cattle contained proportionately more acetic acid, and the proportions of other volatile fatty acids were less than in sheep. These differences were generally associated with differences in selective grazing.

Utilization of whole egg and its components in milk replacers for preruminant lambs

Preruminant male crossbred lambs, aged between 2 and 5 days at the start of the experiment, were given milk replacers in the following experiments. Experiment 1: low (0.10 protein energy) or medium protein (0.25 protein energy) diets that contained whole egg as the sole source of protein, before or after autoclaving at 105° for 60 min. A medium protein diet that contained cows' milk protein was the control treatment. Experiment 2: low protein diets that contained either whole egg (before or after solvent extraction), solvent-extracted egg yolk, egg albumen or dried skim milk as the protein source, with butter oil or egg fat as the fat source. Experiment 3: low protein diets with solvent-extracted egg yolk as the protein source, butter oil as the fat source and supplemented with DL-methionine to raise the concentration of methionine + cystine to that of wholeegg or of egg albumen. Experiment 4: low protein diets containing either solvent-extracted egg yolk or cows' milk as protein source with butter oil as fat source, at a range of intakes of gross energy. All diets were supplemented with DL-methionine to raise the methionine + cystine concentration to that of whole egg. Nitrogen balances, liveweight gains and efficiencies of nitrogen utilization were determined with all diets for a 7-day collection period. All diets containing egg fat were poorly accepted and the digestibility of egg fat was low compared with butter oil. An experiment with weanling rats (experiment 5) showed that the reduction in fat digestibility could not be attributed to the phospholipid component of egg fat. The apparent digestibility of egg fat by rats was significantly less than that of coconut fat or groundnut oil in control diets. Low and medium protein diets containing autoclaved whole egg were more acceptable, and there was a significant increase in apparent nitrogen digestibility in the low protein diet compared with the diet containing unheated whole egg. Utilization of nitrogen in diets containing egg albumen was lower than in diets containing only the egg yolk fraction of whole egg. The addition of DL-methionine to solvent-extracted egg yolk to raise the methionine + cystine content to that of whole egg or egg albumen failed to increase nitrogen balances significantly. An attempt was made in experiment 4 to compare, by the slope-ratio method, the nutritive values of diets containing either egg yolk or cows' milk proteins, with DL-methionine added to raise the methionine + cystine content to that of whole egg. The diets that contained egg yolk were poorly accepted at the higher intake levels, whereas those containing cows' milk were readily accepted at all energy levels. The intercepts of the regression equations relating nitrogen balance to apparently digested nitrogen intake were significantly different. Thus the results did not meet the criteria proposed by Hegsted and Chang (1965) for a valid comparison by the slope-ratio method. A comparison of nitrogen balances, at the mean nitrogen intake of 596 mg nitrogen per day per kg0.73, showed significantly higher nitrogen balances for lambs given the milk protein diet than for those given the egg yolk diet (396 v. 324 mg nitrogen per day per kg0.73). There were no significant differences in liveweight gain. It was concluded that when the intake of apparently digested nitrogen was low (<477 mg nitrogen per day per kg0.73) the absorbed nitrogen from the egg yolk diet was more efficiently utilized than the apparently digested nitrogen from the milk diet, whilst above 477 mg nitrogen per day per kg0.73 the converse was true.

Molasses in broiler and layer diets

The use of molasses in broiler diets was examined in three experiments and in layer diets in one experiment. Up to 20 per cent molasses was fed in broiler diets with no reduction in bodyweight gain but the moisture content of excreta increased as the molasses level in the diet increased. There were no detrimental effects on egg production when up to 16 per cent molasses was fed in layer diets. There was no deterioration in the nutritive value of diets containing molasses stored for four months.

Nutritive Value of Forage and Diets of Sheep and Cattle from Oregon Subclover-Grass Mixtures

During spring-summer over a three-year period, selectivity by both sheep and cattle grazing on subclover-perennial ryegrass and subclover-tall fescue resulted in higher nutritive value of diets than of ungrazed forage. Sheep diets consistently contained more crude protein and had higher in vitro dry matter digestibility than did cattle diets. Both sheep and cattle diets were more digestible under light than under heavy grazing but diet protein levels were inconsistent. In one year stocking rate had no effect on level of protein in the diet and the next year high protein levels were associated with heavy use. Summer vegetative regrowth of tall fescue caused by heavy cattle grazing resulted in levels of dietary protein for cattle similar to those for sheep. The level of dietary protein for sheep exceeded recommended requirements. In the summer, protein levels of cattle diets were near or below requirements except when cattle heavily grazed subclover-tall fescue Dastures.

The nutritive value of separated milk for pigs. III. A note on the effects of supplementary lysine and methionine on performance to 55 kg live weight

SUMMARYAttempts were made to improve the nutritive value of diets based on separated milk and barley by adding free lysine and methionine. Feeding trial and nitrogen metabolism studies showed small beneficial responses to lysine, but not to methionine; the effects however were not statistically significant.

Nutritional Value of Diets in Saigon Orphanages

Nutritional Value of Diets in Saigon Orphanages

Food Intake and Nutritive Value of Diets of Men, Women, and Children in the United States, Spring 1965

Food Intake and Nutritive Value of Diets of Men, Women, and Children in the United States, Spring 1965

Utilization of Unextracted Soybeans by Broiler Chicks: 2. Influence of Pelleting and Regrinding on Diets with Infra Red Cooked and Extruded Soybeans

NUMEROUS workers have reported on various ways to utilize unextracted soybeans in chick diets. These methods, which have included autoclaving, cooking, extruding, infra red cooking, and mechanical flaking and pelleting, have been extensively reviewed by Featherston and Rogler (1966) and White et al. (1967).The latter report was largely concerned with two processes for preparing unextracted soybeans, namely, infra red cooking and extruding. They found that these two methods of preparation supported maximum chick growth when compared to those fed diets containing solvent extracted soybean meal.The experiments reported herein were conducted to further evaluate these two methods of processing unextracted soybeans for broiler diets and to determine the influence of pelleting and regrinding on the nutritive value of diets containing various soybean preparations.MATERIALS AND METHODSExperiment 1. In this and the subsequent experiment in this report, solvent extracted soybean meal and raw whole soybeans were obtained from the

Nutritive Value of Diets in Indian Boarding Schools in the Dakotas

Nutritive Value of Diets in Indian Boarding Schools in the Dakotas

Effect of Water Treatment and Enzyme Supplementation on the Metabolizable Energy of Barley ,

NUTRITIONAL value of diets containing Western barley for poultry is improved by crude enzyme supplements and water-treatment of the barley (Jensen et al., 1957; Fry et al., 1957, 1958; Arscott, 1958, Dobson and Anderson, 1958; Wharton et al., 1958; Berg, 1959). The improved growth and feed utilization observed would suggest a substantial increase in utilization of energy in barley by young chicks. Therefore, a study was made to determine the effect of water-treatment and enzyme supplementation of barley on the metabolizable energy (ME) for chicks. EXPERIMENTALProcedure for determination of ME was essentially the same as that described by Hill and Anderson (1958). The basal diet used in the four experiments is in Table 1. Components of the diets are expressed on moisture free basis. Dietary modifications were accomplished by substituting the test materials at levels of 40% for equal amounts of glucose monohydrate on a dry matter basis. Chromic …

The Effect of Supplemental Methionine on the Nutritive Value of Diets Containing Concentrates of the Soybean Trypsin Inhibitor

Animal experiments involving measurement of the growth performance of rats were conducted to determine the effect of supplemental methionine on diets containing a soybean trypsin inhibitor concentrate and in which the sources of nitrogen were raw or autoclaved soybean protein, soybean protein hydrolysate, or casein. When the soybean hydrolysate or casein was furnished in the diet, the depression in growth exerted by the trypsin inhibitor preparation was not related to interference with the availability of methionine for growth. The beneficial effect of methionine in this instance could be wholly accounted for by the fact that the hydrolysate and casein were deficient to some extent in this amino acid. With diets containing autoclaved soybean meal, the growth-retarding action of the inhibitor was referable to interference with the availability of methionine for growth, as well as to the deficiency observed in the case of the hydrolysate and casein. These results may be explained by postulating a two-fold mode of action by active trypsin inhibitor preparations, one which results in an impairment of the availability of methionine for growth as a consequence of its antiproteolytic activity, and the other having an effect unrelated to the inhibition of proteolysis. The former can be demonstrated if the source of ingested N is an intact protein critically deficient in methionine. The latter effect is independent of the nature and quality of ingested N.

Comparative nutritional value of diets containing rancid fat, neutral fat, and no fat

Comparative nutritional value of diets containing rancid fat, neutral fat, and no fat