• 한국유기농업학회지
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• 제25권4호
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• pp.805-819
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• 2017

The study was carried out to develop a mathematical model for evaluating the effect of organic fertilizers in organic rice production systems. A function to simulate the nitrogen mineralization process in the paddy soil has been developed and integrated into ORYZA2000 crop growth model. Inorganic nitrogen in the soil was estimated by single exponential models, given temperature and C:N ratio of organic amendments. Data collected from the two-year field experiment were used to evaluate the performance of the model. The revised version of ORYZA2000 provided reasonable estimates of key variables for nitrogen dynamics and crop growth in the organic rice production systems. Coefficient of determination between the measured value and simulated value were 0.6613, 0.8938, and 0.8092, respectively for soil inorganic nitrogen, total dry matter production, and rice yield. This means that the model could be used to quantify nitrogen supplying capacity of organic fertilizers relative to chemical fertilizer. Nitrogen dynamics and rice growth simulated by the model would be useful information to make decision for organic fertilization in organic rice production systems.

• Asian-Australasian Journal of Animal Sciences
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• 제18권5호
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• pp.667-670
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• 2005

The proximate analysis, amino acid content and true amino acid digestibility and TMEn for poultry of adult Field crickets Gryllus testaceus Walker, were investigated. The insect was also used as partial replacement of protein supplements in the broiler diet on an equal CP percentage and TMEn basis. The results indicated that the adult insect contained: crude protein 58.3%; fat 10.3%, chitin 8.7% and ash 2.96% on dry matter basis, respectively. The total amounts of methionine, cystine and lysine in the Field crickets were 1.93%, 1.01% and 4.79%, respectively, and their true digestibility coefficients, determined in cecectomized roosters, were 94.1%, 85% and 96%, respectively. The TMEn of this insect meal was 2,960 kcal/kg determined in cecectomized roosters. When cornsoybean meal diets were formulated on an equal CP percentage and TMEn basis, up to 15% Field cricket could replace control diet without any adverse affects on broiler weight gain, feed intake or gain:feed ratio from 8 to 20 d posthatching.

• Asian-Australasian Journal of Animal Sciences
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• 제14권4호
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• pp.501-506
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• 2001

This experiment was conducted to evaluate the effects of supplemental unsaturated fatty acids (UFA) on fermentation characteristics, especially on gas production, cellulose degradation and volatile fatty acid (VFA) concentration by mixed ruminal microorganisms. In order to attain this objective, unsaturated fatty acids including oleic acid (C 18:1), linoleic acid (C18:2) and arachidonic acid (C22:4) were added at varying level. Mixed ruminal microbes used in this experiment were obtained from the rumen of a cannulated Holstein cow. Medium pH values after 7 d incubation were significantly affected by type and level of unsaturated fatty acids (p<0.01). All of UFA inhibited total gas production, and especially treatment of arachidonic acid at the levels of 0.01% gave the lowest gas. production after 7 d incubation (p<0.01). Comparison of the population of protozoa revealed that UFA did not have any significant effect on the total protozoa number. The addition of UFA did not effect dry matter degradation. Volatile fatty acid (VFA) composition of the culture was influenced little by UFA, although the considerable amount of iso-type VFA were detected in UFA supplemented incubations. The ratio of acetic acids to propionic acids, however, was lower than control in all the treatments after 7 d incubation (p<0.01).

• Asian-Australasian Journal of Animal Sciences
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• 제7권2호
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• pp.183-189
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• 1994

Two experiments were made. In experiment 1, four diets containing 0, 5, 15 and 25% washed seaweed meal were prepared to study the effects of incorporating seaweed meal instead of equivalent amounts of berseem leaf meal in fish feeds on growth performance and feed utilization of common carp. The results showed that average daily gain (ADG), specific growth rate (SGR%), dry matter (DM) and ether extract (EE) of the carcasses were decreased (p<0.05) with the increasing level of seaweed meal in the feeds. Inclusion of 5% seaweed meal in the diet gave the best feed conversion ratio (FCR) among all diets, however, protein productive value (PPV) and energy utilization (EU) were decreased (p<0.05) with increasing level of seaweed meal in the diet. In experiment 2, washed seaweed meal was either steam cooked or sprayed with NaOH (0.5% or 1% NaOH) and incorporated in the diets at the level of 25% instead of equivalent amount of berseem leaf meal. The results showed that steam cooked seaweed gave the best (p<0.05) growth performance, FCR and protein efficiency ratios, PER and PPV, for other treatments in descending order were NaOH treated seaweed, washed seaweed and unwashed seaweed.

• Asian-Australasian Journal of Animal Sciences
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• 제29권4호
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• pp.509-515
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• 2016

Twenty Ardi lactating goats were used to investigate the effect of substituting 10%, 15%, and 20% of concentrate feed with date pits on milk production, composition, and blood parameters. Four isocaloric and isonitrogenous dietary treatments were used. Four levels (0% [control], 10%, 15%, and 20%) of date pits were used to replace concentrate feed. The forages to concentrate ratio used was 60 to 40. Dry matter intake (DMI) of goats fed diets containing 10% and 15% date pits was significantly (p<0.05) higher than those fed diets containing 0% and 20%. However, goats fed a diet containing 20% date pits were significantly (p<0.05) lower in DMI compared to those fed control diet. The protein percent was significantly higher for goats fed control diet compared to the other dietary treatments. Total solids percent was significantly the lowest for goats fed diet supplemented with 10% date pits. Goats fed a diet containing 20% date pits was significantly (p<0.05) higher in the total protein compared to those fed a diet containing 10%. In addition, goats fed a diet containing 15% date pits exhibited no significant differences in the total protein percent compared to those fed a diet containing 20% date pits. Triglyceride was significantly higher for goats fed diets containing 10% and 20% date pits compared to those fed 15% date pits. Results obtained in the present study suggest that date pits can be added up to 20% of the concentrate feeds into lactating Ardi goat diets without negative effects on their productive performance.

• 한국수산과학회지
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• 제42권4호
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• pp.360-365
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• 2009

The dietary fiber and crude fiber contents of different thallus regions (blade, stipe, and holdfast) in three brown algae (Laminaria japonica, Ecklonia stolonifera, and E. cava) were detennined at different ages, and then compared with one another. On a dry matter basis, the soluble dietary fiber (SDF) content was highest ($10.8{\pm}0.5%$) in the holdfast of 2-year old L. japonica, and the insoluble dietary fiber (IDF), total dietary fiber (TDF), and crude fiber (CF) contents were highest in the holdfast of 2-year old E. cava at $44.5{\pm}0.7%$, $50.2{\pm}0.5%$, $6.8{\pm}0.7%$, respectively. The IDF, TDF, and CF contents of these three species were measured in the following order: holdfast > stipe > blade, and the SDF contents of L. japonica exhibited the reverse of this trend. The TDF/CF ratio of 1-year old L. japonica, E. stolonifera, and E. cava was greater than was observed in the corresponding 2-year old samples. This is, to the best of our knowledge, the first report demonstrating that the holdfasts of L. japonica, E. stolonifera, and E. cava are rich in dietary fiber contents, especially IDF, TDF, and CF.

• Asian-Australasian Journal of Animal Sciences
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• 제9권2호
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• pp.127-132
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• 1996

Effects on feed intake, liveweight gain and economic benefits of supplementing lambs with urea molasses blocks, were studied. Forty eight crossbred lambs were divided into 6 groups and assigned randomly to grazing on native pasture (CONT) or along with supplements of Commercial ration (COM) and urea molasses blocks (UMBs) containing two levels of cement and calcium oxide as a binding agent. Analysis of variance revealed highly significant (p<0.01) differences in dry matter (DMI, g/day), crude protein (CPI, g/day) and metabolizable energy (MEI, MJ/day) intakes. Differences in liveweight gain (LWG, g/day), feed conversion ratio (FCR) and net economic benefit of supplementation were also highly variable. The intake of DM, CP and ME varied from 974 to 1002, 66-70 and 7.6-8.4 in lambs supplemented with UMBs, significantly (p<0.01) greater than 848, 52.5 and 5.6 in lambs supplemented with COM or FCR and net economic benefits (54.3; 57.8; 17.1 and 1.96; 2.4) in lambs supplemented with COM and UMB-2, were CONT or supplemented with UMB-1, UMB-3 and UMB-4 respectively. Factors responsible for differences in feed intake, liveweight gain and economic benefits, are discussed.

• Asian-Australasian Journal of Animal Sciences
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• 제5권1호
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• pp.33-37
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• 1992

Napier grass (Pennisetum purpureum Schum.) harvested at an early growth stage was ensiled with 4% of molasses in a polyethylene bag silo which contained 15 kg of chopped forage each. Dry matter (DM) content of the silage was so low as 14.75%, although chemical quality of the silage was very high. Ratio of ammonia nitrogen to total nitrogen was 6.59%, and the pH value of the silage was 3.79. Nutritive value of the silage was estimated using goats and compared to that of a timothy hay as a reference ration. Feeding level of each rations was adjusted to a level of nitrogen (N) recommendation. DM and N digestibilities of the silage were 65.0 and 54.5%, respectively, but those of the timothy hay were 37.6 and 37.2%. Feeding of the napier grass silage maintained body weight and kept positive N retention. Ammonia N concentration in the rumen fluid in goats fed the napier grass silage increased after feeding, but blood urea concentration was constant. Feeding of the timothy hay did not increase ammonia N concentration in the rumen fluid, but increased blood urea concentration. These facts indicated that the napier grass silage had enough digestible DM and N for maintenance ration to goats.

• 한국초지조사료학회지
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• 제14권3호
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• pp.223-229
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• 1994

To find out the effects of phosphatic fertilizer application levels on the botanical composition, mineral contents and mineral nutrient deprivation of grasses and the chemical properties of soil, this expriment was arranged as a randomized complete block design with six treatments(0, 50, 100, 150, 200 and 250kg $P_2O_5$/ha) and conducted at hilly land in Gwangju, Gyeonggi Province from September, 1989 to October, 1992. The results obtained are summarized as follows: The botanical composition of grasses without posphatic fertilizer application was poor but with 150kg $P_2O_5$/ha application, remarkably increased in legume of grasses and decreaed in weed. As the phophatic fertilizer levels increase, P, Ca and Mg content of grasses were increased but N and K content tended not to be regular, and Ca/p and K/Ca+ Mg equivalent ratio were lowered. Up to 150kg $P_2O_5$/ha application level, the mineral nutrient content deprived by dry matter yield was increased but with that over application, tend not to be increased. Most of applied mineral elements were accumulated at a subsurface of grassland and as the phosphatic fertilizer application levels increase, the available $P_2O_5$ and exchangeable Mg contents of the soil tended to be remarkably increased and exchangeable K content tended to be decreased, but pH, OM and exchangeable Ca content tended not to be regular.

• 한국잠사곤충학회지
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• 제19권1호
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• pp.9-13
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• 1977

누에의 인공사료에 첨가하는 cellulose의 종류별 제제방법별 및 첨가량별로 사육시험을 행한 결과를 요약하면 다음과 같다. 1. 공시한 cellulose 중에서는 뽕나무 cellulos가 잠체중과 견층비율이 높고 감잠비율은 낮으며 경과일수도 짧아서 가장 우수하고 그 다음이 소나무 cellulose로서 뽕나무 cellulose와 거의 비슷한 사육성적을 나타내었다. 2. Cellulose조제방법은 PA법이나 NaOH처리법이나 서로 비슷한 사육성적을 나타내었으며 cellulose원에 따른 차이도 거의 인정되지 않았으나 무처리 cellulose는 극히 불량하였다. 3. 인공사료에 첨가하는 cellulose의 양은 건물사료의 15∼22.5%범위가 적당한 것으로 나타났다.