• Environmental Engineering Research
• /
• v.21 no.1
• /
• pp.29-35
• /
• 2016

This study evaluated the fertilizing value of struvite deposit recovered from swine wastewater in cultivating lettuce. Struvite deposit was compared to complex fertilizer, organic fertilizer and compost to evaluate the fertilizing effect of struvite deposit. Laboratory pot test showed that the struvite deposit better enhanced lettuce growth in comparison to commercial fertilizers. It was revealed that the growth rate of lettuce was simultaneously controlled by phosphorus (P) and magnesium (Mg). Moreover, nutrients such as nitrogen (N), P, K, calcium (Ca) and magnesium (Mg) were abundantly observed in the vegetable tissue of struvite pot. Meanwhile, struvite application led to the lower accumulation of mercury (Hg), lead (Pb), chromium ($Cr^{6+}$) and nickel (Ni). In addition, no detection of cadmium (Cd), arsenic (As) and nickel (Ni) in the lettuce tissue was observed in struvite application pots. The experimental results proved that the optimum struvite dosage for lettuce cultivation was 0.5 g struvite/kg soil. The column experiments clearly showed that ammonia nitrogen was more slowly released from struvite deposit than from complex fertilizer. Consequently, it was concluded that the struvite deposits recovered from swine wastewater were effective as a multi-nutrient fertilizer for lettuce cultivation.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.44 no.2
• /
• pp.136-147
• /
• 2002

Characteristics of unit loads of pollutants were investigated at a paddy fields area(Soro-ri) with large-scaled plots on loam soil during irrigation seasons of 1999 ∼2000. The average irrigation requirement of experimental paddy area are estimated at over 3,000 mm. The unit loads of pollutants in paddy fields area are determined by subtracting irrigation water load from outflow load (percolated and surface outflow loads). Surface outflow load in rainy days was calculated using the relationships of discharge and load, which are grouped into fertilizing and non-fertilizing periods. The ratios of the surface outflow load in rainy days to the total surface outflow load are 16.4% for T-N, 26.8% for T-P, and 23.3% far CODc,. The unit loads of pollutants show month-to-month and year-to-year variations, and monthly unit load of pollutants can show negative values, indicating that the paddy area acts as the pollutants sink. The average unit loads of the pollutants during irrigation seasons were estimated at 18.2 kg/ha fur T-N, 0.31 kg/ha for T-P, and 43.3 kg/ha for CODc,, which are smaller than the reported values for Kosei area in Japan.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.10 no.3
• /
• pp.158-163
• /
• 1990

This experiment was to study the effect of pure mineral nitrogen fertilizing on seasonal distribution of dry matter yield and the advisable mineral nitrogen amounts on grassland. The results were as follows: 1. With longer regrowth periods the absolute dry matter yields and the nitrogen-efficiences due to nitrogen fertilizing increased substantially, whereas the quality declined at the relatively lesser cutting frequencies. 2. The first cut at 3-cut regimes, the first and fourth cut at 4-cut regimes, and the second and last cut at 5-and 6-cut regimes showed the highest nitrogen-efficiency, respectively. 3. By the sigmaformed process of production curve the most efficient mineral N-dressing rate per ha and cut was calculated: 42-56kg N on the 3-cut areas, 39-55kg N on the 4-cut areas, 38-47kg N on the 5-cut areas and 35-48kg N/ha/cut on the &cut areas. 4. In dependence on site and kind of calculation the economical borders were reached with the following dressings of mineral N/ha/cut: 90-100kg on the 3-cut areas, 70-100kg on the 4-cut areas and 50- 90kg on the 5-and 6-cut areas.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.2 no.2
• /
• pp.65-75
• /
• 1994

The aim of this experiment was to investigate the effects of applying time of cattle slurry and fertilizing added mineral nitrogen on dry matter yield of orchardgrass and also to estimate proper levels of fertilizing nitrogen when idled arable land rapidly increased these days, which was used for the production of Orchardgrass. The results were as follows. 1. The annual yields of dry matter were produced 5.62~6.67 ton per ha when cattle slurry applied at rates of $30m^3$(average mineral fertilizer equivalent to 120kg) per ha in different dressing times. Those were higher 0.60~1.65 ton or 0.16 ton per ha than the yields from non-fertilizing or phosphrous and potassium fertilizing. 2. Relative yields of annual dry matter from mineral nitrogen fertilization of 120kg per ha were 142~146% in comparsion with control plots(cattle slurry plot or phosphrous and potassium plot). On the other hand, those of cattle slurry application were 112~133% in comparion with non-fertilizing plot. 3. The efficiencies of nitrogen on dry matter yield(kg DM/kg N) were 5.0~13.8 DM kg/N kg when cattle slurry applied to Orchardgrass at rates of $30m^3$(average mineral fertilizer equivalent to 120kg) per ha, and were 21.3~23.1kg DM/kg N at the same level fertilization of mineral nitrogen. 4. On the condition of this study, mineral nitrogen were fertilized after applying cattle slurry at rates of $30m^3$(average mineral fertilizer equivalent to 120kg) per ha in order to minimize chemical fertilizer and increase the potential production of Orchardgrass. At this situation, marginal dry matter yields of 8.48~8.63 ton per ha were obtained as the level of economic even point goint when mineral nitrogen fertilization is between 119.4 and 133.3kg per ha. It was possible to obtain the maximal dry matter yield(8.98 tons/ha) with fertilization of 202.8kg N/ha.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.51 no.5
• /
• pp.379-385
• /
• 2006

This experiment was carried out to investigate the optimum planting density in low fertilizing cultivation of machine transplanting in rice field of Honam Agricultural Research Institute, NICS for $2004{\sim}2005$. Sobibyeo which belongs to medium maturing variety and Nampyeongbyeo which belongs to medium-late maturing variety were transplanted on May 30. In this experiment, there was no significant difference in heading date between planting density and nitrogen fertilization rate, and heading dates were August 8 in Sobibyeo, and August 14 in Nampyeongbyeo respectively. In relation to lodging character, lodging Index was high where the nitrogen fertilization rate and planting density were high. As planting density increases, panicle number per $m^{2}$ increased irrespective of nitrogen fertilization rate. When nitrogen was 6 kg/10a, rice yield of Sobibyeo was more where planting density was 90 hill per $3.3m^{2}$, and that of Nampyeongbyeo was more where planting density was 80 hill per $3.3m^{2}$. When nitrogen was 9 kg/10a, rice yield of Sobibyeo was more where planting density was 100 hill per $3.3m^{2}$, and that of Nampyeongbyeo was more where planting density was 110 hill per $3.3m^{2}$. Head rice rate of brown rice was higher when planting density increased, and was higher at 6 kg/10a nitrogen rate than 9 kg/10a nitrogen rate in all varieties.

• Korean Journal of Veterinary Research
• /
• v.32 no.3
• /
• pp.435-450
• /
• 1992

To evaluate the fertilizing capacity of domestic animal spermatozoa by hamster test, semen were collected from 15 boars(Duroc, Landrace, and Yorkshire) and 2 mixed dogs which had been proved to be fertile in the past then, the semen were preserved in BWW medium at $4^{\circ}C$ or $18^{\circ}C$ for about 20 hours and coincubated with zona-free hamster ova for 5 hours. The ova were stained by lacmoid and examined under phase contrast microscope to investigate the rates of sperm binding to the ova, penetration and formation of a male pronucleus, and the numbers of both bound and penetrated sperm per ovum. Both the semen preserved at $18^{\circ}C$ for about 20 hours and that treated by swim up procedure showed considerably higher rates of sperm binding and penetration as well as higher number of penetrated sperm than that preserved at $4^{\circ}C$ for about 20 hours, respectively(p<0.01). Motility of boar sperm at insemination was from 40 to 90% and no difference in hamster test was obtained according to different degree of sperm motility. Abnormality in morphology of boar sperm at insemination was from 6 to 45% and no difference in hamster test was obtained according to different degree of sperm abnormality. The sperm concentrations of $7{\times}10^7$ and $7{\times}10^6$ showed considerably higher rates of sperm binding and penetration as well as higher number of bound sperm than that of $7{\times}10^4$ (p<0.01) along with the same higher results than that of $7{\times}10^5$(0<0.05), respectively. Boar sperm showed considerably higher rates of sperm binding and penetration as well as higher numbers of both bound and penetrated sperm than dog sperm, when both semen were treated by BWW＋heparin medium and swim up procedure, respectively. These results indicated that fertile boar sperm showed considerably lower rates in the results of hamster test, when preserved at $4^{\circ}C$ for about 20 hours and in lower concentration of sperm than when preserved at $18^{\circ}C$ for about 20 hours and in higher concentration of sperm, respectively, and at the same time considerably higher results than fertile dog sperm, consequently to prove that hamster test would be of great value in assaying the fertilizing capacity of boar sperm.

• Journal of Veterinary Clinics
• /
• v.9 no.2
• /
• pp.373-390
• /
• 1992

To assay the fertilizing capacity of domestic animal spermatozoa by hamster test, semen were collected from 13 boars(Duroc. Landrace and Yorkshire) which had been proved to be fertile in the past. then, were preserved in BWW medium or in raw state at 18$^{\circ}C$ or at room temperature. The preserved semen were given each different treatment according to the experimental design and coincubated with zona-free hamster ova for 5 hours. The ova were stained by lacmoid and examined under phase contrast microscope to investigate the rates of ova bound with sperm(sperm binding). ova penetrated by sperm(penetration) and formation of a male pronucleus(pronucleus formation) and also numbers of both bound and penetrated sperm per ovum. Between BWW and TBM medium for boar sperm. no difference in the results of hamster test was obtained. The boar spermatozoa in BWW medium, BWW with caffeine, BWW with heparin, and BWW with both caffeine and heparin showed no difference in the results of hamster test. The boar spermatozoa in BWW medium containing both calcium and RSA showed considerably higher rates of sperm binding, penetration and pronucleus formation as well as higher numbers of both bound and penetrated sperm than those not containing calcium with or without BSA( p<0.01) and also the same results higher than that containing calcium without BSA( p< 0.05). The boar spermatozoa irradiated by X-ray(70 KVP, 20mA) for 3 seconds. then, maintained at 18$^{\circ}C$ for 18 hours showed considerably lower rate of sperm binding than all the other groups including the control and X-ray groups irradiated by smaller dose or maintained for shorter period(p<0.01), and also showed lower number of bound sperm than the other groups(p<0.01, p<0.05). All the control groups of both raw and diluted sperm in BWM medium showed higher rates of sperm binding, penetration and pronucleus formation as well as higher number of penetrated sperm than all the X-ray groups irradiated for 3 seconds(70KVP, 20mA) and maintained for either 3 or 18 hours (p<0.01, p<0.05). At the same time the control groups of diluted sperm showed considerably higher rates of sperm penetration and pronucleus formation than the control group of raw sperm( p<0.01). These results indicates that fertile boar sperm showed considerably lower rates In the results of hamster test, when incubated in the medium without calcium and irradiated by X-ray than when incubated in the medium with calcium and not irradiated by X-ray, respectively, to prove consequently that hamster test would be of great value in assaying the fertilizing capacity of boar spermatozoa.

• Journal of Embryo Transfer
• /
• v.25 no.4
• /
• pp.263-266
• /
• 2010

Prediction of semen's fertilizing ability used in artificial insemination (AI) is one of very important factors on pig reproductive performance. In vitro fertilization (IVF) has been used for indirect evaluation of sperm's fertilizing ability and it has been showed as highly correlated index. In swine industry, increasing interest in preservation of boar semen raises questions on the sperm motility from semen used in commercial AI centers. Mitochondria in sperm mid-piece generate the energy to support motility and could be an explanation of impaired fertility. Objective of this study was to suggest usable sperm motility to farms in measuring the effect of sperm motility and sperm abnormality on in vitro production of embryo in which sperm's fertilizing ability can be determined indirectly. Semen samples were provided from local AI center and used within 3 days after collection. Semen samples were divided by 4 different motile groups (>70%; 61~70%; 51~60%; <50%) using CASA (computer-assisted sperm analysis) on the days of IVF. Developmental rate to the blastocyst stage from over 61% motile sperm group showed significantly higher rate than below 60% motile sperm group ($16.5{\pm}0.7{\sim}18.4{\pm}0.8%$ vs $6.3{\pm}0.8{\sim}11.5{\pm}0.7%$, p<0.05). In experiment to determine the relationship between sperm motility and viability and abnormality, over 61% motile sperm groups showed significantly higher viability rate compared to below 60% motile sperm groups ($84.8{\pm}4.0{\sim}88.1{\pm}4.0%$ vs $69.1{\pm}4.0{\sim}74.2{\pm}4.0%$, p<0.05). On the other hand, morphological sperm abnormality showed significantly higher in over 70% motile sperm group ($10.2{\pm}2.2$ vs $16.0{\pm}2.2{\sim}21.0{\pm}2.2%$, p<0.05). In experiment to find the correlation between sperm motility of 4 different motile groups and amount of mitochondria, lower motility group also showed lower level of mitochondria (p<0.05). The mitochondria parameter used in this study showed another possibility to differentiate the sperm motility. Taken together, because below 60% motile semen used in AI reduce the fertility, AI centers should provide the over 60% motile sperm to the farms at the time of AI.

• Asian-Australasian Journal of Animal Sciences
• /
• v.6 no.3
• /
• pp.447-450
• /
• 1993

The effect of adding transparent fluid (TF) to fowl semen on fertilizing capacity of fowl spermatozoa and on hatchability was studied. Diluted semen and semen containing 15% TF were stored for 24 h at $3-5^{\circ}C$ and inseminated at weekly basis for 5 consecutive weeks. No significant differences were observed in fertility, hatchability and embryonic mortality among the treatments. The results suggest that TF is not necessarily detrimental to fowl spermatozoa even when mixed with semen and stored outside the body.

• Korean Journal of Animal Reproduction
• /
• v.23 no.4
• /
• pp.353-358
• /
• 1999

Four important attributes for successful fertilization by a spermatozoon are (ⅰ) correct morphology, (ⅱ) correct presentation of egg recognition and fusion molecules, (ⅲ) progressive motility and (ⅳ), correct transfer of signalling molecules from sperm to egg for activation of development. In this presentation, these topics will be described and illustrated with emphasis on the endogenous control mechanisms that enable spermatozoa to respond to external signals. (omitted)