• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.5
• /
• pp.630-638
• /
• 2021

In this study, we investigated the effects of dissolved inorganic and organic nutrient on the growth of dinoflagellate Alexandrium affine (LIMS-PS-2345). The maximum uptake rates (ρ_max) and half saturation constants (Ks) calculated from the uptake kinetics experiment were 77.0 pmol/cell/hr, 17.6 μM for nitrate and 15.5 pmol/cell/hr, 3.88 μM for phosphate, respectively. These results suggested that this species has high inorganic nutrient demand and a low affinity for inorganic nutrients. During the utilization of organic nutrients for A. affine, growth rates of experimental groups added by organic nitrogen (urea and glycine) and phosphorus (adenosine triphosphate and glycerol phosphate) were above 70 %, compared to the experimental groups added by inorganic nutrients. Thus, A. affine may need to utilize organic nutrients to understand the dominant strategy and advantageous position in the interspecific competition within low inorganic nutrient environments.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2003.05a
• /
• pp.223-224
• /
• 2003

Information on the fate of the added nutrients is essential for the assessment of the food utilization, pond fertility, water quality and processes in the sediment (Boyd, 1985). Also, they are useful for qualifying environmental impacts of aquaculture and for environmental management. The purpose of this experiment was to assess the fate of nitrogen and organic matter entering aquaculture ponds and the relative importance of the different resources. (omitted)

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2001.05a
• /
• pp.90-91
• /
• 2001

• Journal of the Korean Chemical Society
• /
• v.19 no.4
• /
• pp.252-257
• /
• 1975

This experimental study was carried out to examine the utilization of the anthracite ash as a fertizer. It was found that the ash had very small amount of the soluble matters in 2% citric acid solution therefore it is proved ineffective as a fertilizer. When the small amount of calcinated dolomite was added to the anthracite, it was observed that the resulting ash showed much increased solubility of magnesium, calcium, sulfur and silica etc in the citric acid solution. So it is concluded that the ash of the mixture of anthracite and calcinated dolomite would be one of the useful soil-conditioner and supplyer of nutrients.

• Journal of Nutrition and Health
• /
• v.23 no.5
• /
• pp.309-316
• /
• 1990

The relationship between diet diversity and nutrient intake was studied. Diet diversity, caloric intake and dietary nutrient density values were examined as contributors to the level of selected nutrients with the use of data obtained from 14-day dietary records of 60 college women. The subjects were grouped into quartiles on the basis of level of intake of each of the specific nutrients. The indexes of diet diversity were the number of different food items and Shannon & Weaver's diversity index. Differences in diet diversity were found among nutrients and indexes. In general, calorie and protein intake were more diverse, on the other hand, intake of vitamins A and C were less diverse. With the exception of calcium, iron, vitamin $B_1$, niacin and vitamin C, the number of food items increased at each quartile of intake of specific nutrients. It was concluded that for some nutrients(as with fat), the number of food items consumed may be useful in estimating nutrient intakes. For other nutrients(as with calcium), utilization of nutrient-specific diversity indexes is necessary. Increased nutrient intake was accompanied by increased caloric intake(except vitamins A and C) and dietary nutrient density for all nutrients.

• Korean Journal of Organic Agriculture
• /
• v.10 no.1
• /
• pp.35-47
• /
• 2002

In swine production, efficiency of utilization of nutrients is imperative. By embracing advances in processing techniques(i.e., fine grinding, pelleting, steam flaking, roasting, extrusion and expanding) nutrient utilization of feeds turfs have greatly improved. Grinding is by far the most commonly used process with reduction of particle size, Expander, like extruders, are high-temperature and pressure-short-term processor. The purpose of using an expander is to improve pellet quality. Also, expanding of dietary ingredients indicates improvements in growth performance and nutrient digestibility. Because feed cost are easily the greatest economic input into swine production, maximizing nutrient utilization is an area that will continue to receive much attention. Therefore, much attention will continue to be placed on feed processing techniques that will give consistent improvements in animal performance and nutrient digestibility.

• Korean Journal of Poultry Science
• /
• v.22 no.4
• /
• pp.203-211
• /
• 1995

In order to investigate the effect of feeding live yeast on growth performance, nutrients utilization, tibia mineral deposit and intestinal microorganism changes, a growth assay was conducted with 360 broiler chicks. Treatments were four levels of yeast as 0, 0.025, 0.05 and 0.1% in 1.83% tricalcium phosphate and two levels of yeast as 0 and 0.05% in 1.15% tricalcium phosphate. The crude protein content of live yeast was 45%, and 97% of it was in the pure protein form, with 46.6% of essential amino acids and 53.4% of non-essential amino acids. Growth performance was tended to increase by feeding the yeast but there was no significant difference(P>.05). The protein digestibility was increased as the feeding level of yeast increased. However, digestibilities of fat, fiber, calcium and phosphorus were not affected by the yeast. Ash and calcium content of tibia were increased as the level of yeast increased. Total number of E. coli in small intestine was significantly decreased(P<.05) in chicks fed yeast. Total number of Lactobaci1lus was significantly increased by the yeast feeding. The changes of microorganism in cecum had the same trend with the changes of microorganism in small intestine.

• Asian-Australasian Journal of Animal Sciences
• /
• v.12 no.5
• /
• pp.723-727
• /
• 1999

Two experiments were conducted to determine the effect of feeding levels on intake and nutrient utilization of oat (Avena sativa) hay (OH) by goats and potential feeding value of leftovers from high levels of offer in sheep. In experiment 1, the goats (15) were offered OH at three levels of feeding to give leftovers of about 20% (T-1), 35% (T-2) and 50% (T-3) of DM offered. A marked effect of refusal rate of OH on intake and digestibility of nutrients was evident. Allowing selective consumption at higher levels (T-2 and T-3), the intake of DCP and TDN from OH was found not only to meet the maintenance requirement but provided surplus nutrients for moderate production. In experiment 2, Sheep (3) were offered one of the three dietary treatments viz OH, refusals left uneaten by goats in T-2 and T-3 (OHR) and 3% urea treated oat hay refusals (UTR) in a $3{\times}3$ latin square design. Though the potential feeding value of leftovers (OHR and UTR) was lower than OH, the results confirm the possibility of their effective use. It was concluded that feeding above the conventional ad libitum level could be an alternative to improve the performance of ruminants fed feeds like oat hay. The potential impact of the strategy would, however, depend on the effective reutilization of leftovers for feeding other animals.

• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.12
• /
• pp.1669-1679
• /
• 2015

The quest to broaden the narrow range of feed ingredients available to pig producers has prompted research on the use of low cost, unconventional feedstuffs, which are typically fibrous and abundant. Maize cobs, a by-product of a major cereal grown worldwide, have potential to be used as a pig feed ingredient. Presently, maize cobs are either dumped or burnt for fuel. The major challenge in using maize cobs in pig diets is their lignocellulosic nature (45% to 55% cellulose, 25% to 35% hemicellulose, and 20% to 30% lignin) which is resistant to pigs' digestive enzymes. The high fiber in maize cobs (930 g neutral detergent fiber/kg dry matter [DM]; 573 g acid detergent fiber/kg DM) increases rate of passage and sequestration of nutrients in the fiber reducing their digestion. However, grinding, heating and fermentation can modify the structure of the fibrous components in the maize cobs and improve their utilization. Pigs can also extract up to 25% of energy maintenance requirements from fermentation products. In addition, dietary fiber improves pig intestinal health by promoting the growth of lactic acid bacteria, which suppress proliferation of pathogenic bacteria in the intestines. This paper reviews maize cob composition and the effect on digestibility of nutrients, intestinal microflora and growth performance and proposes the use of ensiling using exogenous enzymes to enhance utilization in diets of pigs.

• Asian-Australasian Journal of Animal Sciences
• /
• v.23 no.10
• /
• pp.1386-1398
• /
• 2010

Soybean contains a high concentration of carbohydrates that consist mainly of non-starch polysaccharides (NSP) and oligosaccharides. The NSP can be divided into insoluble NSP (mainly cellulose) and soluble NSP (composed mainly of pectic polymers, which are partially soluble in water). Monogastric animals do not have the enzymes to hydrolyze these carbohydrates, and thus their digestion occurs by means of bacterial fermentation. The fermentation of soybean carbohydrates produces short chain fatty acids that can be used as an energy source by animals. The utilization efficiency of the carbohydrates is related to the chemical structure, the level of inclusion in the diet, species and age of the animal. In poultry, soluble NSP can increase digesta viscosity, reduce the digestibility of nutrients and depress growth performance. In growing pigs, these effects, in particular the effect on gut viscosity, are often not so obvious. However, in weaning piglets, it is reported that soy oligosaccharides and soluble NSP can cause detrimental effects on intestinal health. In monogastrics, consideration must be given to the anti-nutritive effect of the NSP on nutrient digestion and absorption on one hand, as well as the potential benefits or detriments of intestinal fermentation products to the host. This mirrors the needs for i) increasing efficiency of utilization of fibrous materials in monogastrics, and ii) the maintenance and improvement of animal health in antibiotic-free production systems, on the other hand. For example, ethanol/water extraction removes the low molecular weight carbohydrate fractions, such as the oligosaccharides and part of the soluble pectins, leaving behind the insoluble fraction of the NSP, which is devoid of anti-nutritive activities. The resultant product is a high quality soy protein concentrate. This paper presents the composition and chemical structures of carbohydrates present in soybeans and discusses their nutritive and anti-nutritive effects on digestion and absorption of nutrients in pigs and poultry.