• Journal of Veterinary Clinics
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• v.19 no.1
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• pp.73-79
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• 2002

To investigate the usability of frozen canine embryos for embryo transfer in the dog, 19 donors, 3 recipients, and 6 male dogs were used for the experiment. Natural mating or artificial insemination was performed for breeding the bitches in natural estrus. Vaginal smear test along with progesterone titre test were performed to detect the appropriate mating time and the bitches were bred twice during 3-6days following LH surge. Embryo collection was done on 8, 9-11, 12-13 days after the second mating to collect morula and blastocyst. Embryos were frozen using a programmable freezer and preseued in LNE tank. Embryos were thawed in 37$^{\circ}C$ water for 15 seconds and transferred into each uterine horn within 30 minutes. Embryos were collected from 13 bitches of 19 donors(68.4%) and the collected embryos were from between 9 and 13 days after 2nd mating. Embryos were produced both by natural mating(60.0%, 9115) and AI with frozen semen(100.0%, 4/4). Embryos were collected from the donors weighed between 2.5 and 30 kg and their age was from 1.5 to 3 years. 52 embryos were collected from 13 donors and the mean number of embryos was four. The stage of embryos was from 2-cell to gastrula and morulae were colledted mostly from 10 to 11 days after 2nd mating. Embryos were collected evenly from each uterine horn and the rate of embryo collection for the number of corpus luteum was 83.9%. Embryos were transferred to 3 recipients(morula 8, blastocyst 1, gastrula 8), however, no offspring was produced.

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.2
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• pp.189-191
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• 2010

The black soldier fly, Hermetia illucens, has a worldwide distribution in the tropics and warm temperate regions and is active in the Korea from May through October. This species colonize a wide variety of decomposing vegetable and animal matter and oviposits in a variety of decomposing materials. In this study, how the black soldier fly pupation, adult emergence and mating rate changed with season at the artificial rearing system was investigated. The black soldier fly larvae and pupae were reared under laboratory condition ($27^{\circ}C$, 60% R.H.). In this study, under the laboratory condition, pupation and adult emergence were not influenced by season, but the data shows definitely different mating numbers throughout whole year. The time of the day is changed with seasons and it influence to mating on artificial rearing. To culture the black soldier fly throughout the year in Korea needs a more deep study under the artificial rearing system.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.519-524
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• 2017

The present study investigated the impacts of mating age of gilts (A1, < 230 days; A2, 230 - 249 days and A3, $250{\leq}days$) on reproductive performance and litter size of sows at farrowing to weaning. A total of 102 crossbred gilts ($Yorkshire{\times}Landrace$; average days old, 90 days) were purchased from a commercial breeding company. After identification of third estrus, the gilts were artificially inseminated using semen of Duroc boars. Pregnant pigs were allotted to one of three groups including A1, A2, and A3. Experimental diets and water were fed ad libitum during each experimental period which included the first, second, and third parities. Backfat thickness (BFT) of sows was higher in A3 at farrowing in the first parity than in others. At weaning time in the second parity, sows in A3 group showed a numerically higher BFT than those in A1. There was no effect of mating age on the total number of piglets born and total weaned piglets. There was a tendency to decrease the wean-to estrus-interval in the first parity as age increased at mating. Results obtained in the present study indicate that the first mating age does not affect the subsequent parites' reproductive performance; however, weaned to estrus interval tended to decrease in A2 at the first parity.

• Korean journal of applied entomology
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• v.30 no.2
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• pp.101-105
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• 1991

The host finding, ovipostition of Anagrus incarnafus Haliday and the sex ratio of its offsprings was determined. Both male and female mate immediately after emergence and the female parasitoid search for host eggs by drumming with antenna immediately after release on the rice seedings. Time required for the host searching, drumming with antenna, tapping and inserting with ovipositor, and ovipositing of A. incarnaws takes 188.5, 17.5, 72.4 and 206.7 seconds, respectively. The time required for mating takes 16-21 seconds. The sex ratio of offsprings between female and male was about 3: 1 in mated females and all the offsprings emerged from the eggs of unmated females were males. So, A. incarnafus can reproduce zygogenetically and parthenogenetically and the mode of parthenogenetic reproduction was an arrhenotokous parasitoid.

• Korean Journal of Veterinary Research
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• v.37 no.4
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• pp.899-909
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• 1997

The aim of this study was to assess the estimates of the time of ovulation and mating derived by plasma progesterone concentration. The 40 mature Korea Jin-do bitches were monitored to determine the plasma progesterone concentrations from proestrus to parturition. Gestation length in the 30 pregnant bitches was $63.9{\pm}2.3$ ($mean{\pm}SD$) days in multiparous bitches and $61.8{\pm}3.6$ days in primiparous bitches when Day 0 was timed from the first day of male acceptance, and $61.4{\pm}1.8$ days and $61.3{\pm}2.7$ days when Day 0 was timed from the day of first mating, respectively. Also, gestation length was $63.1{\pm}1.4$ days, $62.4{\pm}1.1$ days and $61.5{\pm}0.9$ days in multiparous bitches, and $62.6{\pm}1.4$ days, $62.4{\pm}2.0$ days and $61.6{\pm}2.3$ days in primiparous bitches when Day 0 was timed from the day that plasma progesterone concentration was first increased above 2.0, 3.0 and 4.0ng/ml, respectively, and $53.8{\pm}3.1$ days and $54.8{\pm}2.6$ days when Day 0 was timed from the last day of male acceptance, respectively. In 30 pregnant bitches, plasma progesterone concentration was $0.2{\pm}0.2ng/ml$ in multiparous bitches and $0.7{\pm}0.8ng/ml$ in primiparous bitches at the first day of vulval bleeding, $1.9{\pm}1.0$ and $3.3{\pm}2.7ng/ml$ at the first day of male acceptance, $7.0{\pm}4.0$ and $9.3{\pm}6.2ng/ml$ at the day of first mating, and $25.1{\pm}6.3$ and $22.8{\pm}10.3ng/ml$ at the last day of male acceptance, respectively. When Day 0 was timed from the day of parturition, plasma progesterone concentration at Day -62, Day -63 and Day -64 was $4.7{\pm}2.7ng/ml$, $3.5{\pm}2.2ng/ml$ and $1.7{\pm}0.9ng/ml$ in multiparous bitches, and $5.3{\pm}4.4ng/ml$, $3.2{\pm}3.7ng/ml$ and $2.0{\pm}1.9ng/ml$ in primiparous bitches, respectively. When Day 0 was timed from the day that plasma progesterone concentration was first increased above 3.0ng/ml after the first day of vulval bleeding, plasma progesterone concentration at Day 61 and Day 62 was $2.7{\pm}2.2ng/ml$ and $1.4{\pm}1.9ng/ml$ in multiparous bitches, and $3.4{\pm}5.2ng/ml$ and $3.7{\pm}5.6ng/ml$ in primiparous bitches, and $0.8{\pm}0.7ng/ml$ and $0.9{\pm}0.4ng/ml$ at Day 63, respectively. It was that bitches were mated when plasma progesterone concentraion was 1.9 to 14.2ng/ml and 3.5 to 20.0ng/ml in multiparous and primiparous bitches, which was between first day before ovulation and fourth day after ovulation. And pregnancy rate was 92% (23/25). From these data, ovulation was estimated to occur the day when plasma progesterone concentration was first increased above 3.0ng/ml after the first day of vulval bleeding. It was estimated that mating time was the day when plasma progesterone concentration was between 1.9 and 20.0ng/ml, and best time for mating was between 3.0 and 8.0ng/ml of plasma progesterone concentration.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.177-183
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• 2014

The ussur brown katydid, Paratlanticus ussuriensis (Orthoptera: Tettigoniidae), causes substantial damage in orchard areas in South Korea. Daily rhythm and mating behaviors were investigated in last instar nymphs, immature adults and mature adults of P. ussuriensis. The daily rhythm was repeated upon resting, moving, and feeding. The daily rhythm of the movement behavior similar in both last instar nymphs and immature adults. Last instar nymphs becoming active at 10:06 and ceasing activity at 21:12 in average. Immature adults becoming active at 11:30 and ceasing activity at 20:08 in average of totally 10 individuals. However, mature adults showed a different active time of 15:30. Generally, behavior was affected by the conditions of their environment, especially temperature. Mature adults activated later than nymphs and immature adults. Mature adults display mating behavior at a particular time of day (approximately 20:00). P. ussuriensis showed a mating behavioral sequence which was similar to related species in completely retaining the spermatophylax. Females took 270 min to 360 min to completely retain the spermatophylax. The daily rhythm of P. ussuriensis, indicating its occurrence and ecology, could be useful as basic data for managing field populations of P. ussuriensis.

• Mycobiology
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• v.46 no.1
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• pp.64-71
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• 2018

The aim of this study was to investigate the pattern of distribution of mating type (MAT) genes of Tuber indicum in ectomycorhizosphere soils from natural T. indicum-producing areas and cultivated truffle orchards and ascocarp samples from different regions. Quantitative real-time PCR and multiplex PCR were used to weight the copy numbers of MAT1-1-1 and MAT1-2-1 in natural truffle soils and cultivated orchard soils. The effect of limestone on the pattern of truffle MAT genes and the correlation between soil properties and the proportion of MAT genes were also assessed. These results indicated that an uneven and nonrandom distribution of MAT genes was common in truffle-producing areas, cultivated truffle orchards, and ascocarps gleba. The competition between the two mating type genes and the expansion of unbalanced distribution was found to be closely related to truffle fructification. Limestone treatments failed to alter the proportion of the two mating type genes in the soil. The content of available phosphorus in soil was significantly correlated with the value of MAT1-1-1/MAT1-2-1 in cultivated and natural ectomycorhizosphere soils. The application of real-time quantitative PCR can provide reference for monitoring the dynamic changes of mating type genes in soil. This study investigates the distributional pattern of T. indicum MAT genes in the ectomycorhizosphere soil and ascocarp gleba from different regions, which may provide a foundation for the cultivation of T. indicum.

• Animal Bioscience
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• v.34 no.1
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• pp.26-35
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• 2021

Objective: This study was conducted to assess the level of pregnancy-associated glycoprotein (PAG) in whole and skim milk samples, and its suitability for early pregnancy diagnosis in goats. Methods: A two-step sandwich enzyme-linked immunosorbent assay (ELISA) system for estimation of milk PAG was developed and validated, which employed caprine-PAG specific polyclonal antisera. Whole and skim milk samples (n = 210 each) from fifteen multiparous goats were collected on alternate days from d 10 to d 30, and thereafter weekly till d 51 post-mating. PAG levels in milk samples were estimated by ELISA and the pregnancies were confirmed at d40 post-mating by transrectal ultrasonography (TRUS). Results: The level of PAG in whole and skim milk samples of both pregnant and nonpregnant goats remained below the threshold values until d 24 after mating. Thereafter, PAG concentration in whole and skim milk increased steadily in pregnant goats, whereas it continued below the threshold in non-pregnant does. The PAG profiles in whole and skim milk of pregnant goats were almost similar and exhibited strong positive relationship (r = 0.891; p<0.001). Day 26 post-mating was identified as the first time-point for significantly (p<0.05) higher milk PAG concentration in pregnant goats than to non-pregnant goats. When compared to TRUS examination for pregnancy diagnosis, the accuracy and specificity of PAG ELISA using whole and skim milk samples were 94.5% and 95.4%; and 95.3% and 100%, respectively. The high values of area-under-curve (0.904 [whole milk] and 0.922 [skim milk]), demonstrate outstanding discrimination ability of the milk assays. Among the sampling dates chosen, d 37 post-mating was identified as the best suitable time point for collection of milk samples to detect pregnancy in goats. Conclusion: The PAG concentration in whole and skim milk of goats collected between days 26 and 51 post-breeding can be used for the accurate prediction of pregnancy and may be useful for assisting management decisions in goat flocks.

• Korean Journal of Veterinary Research
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• v.28 no.1
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• pp.115-118
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• 1988

Mating experiments were performed to, elucidate the distribution of perfect state of Microsporum gypseum complex originated from animals and soils in Korea. A total of 30 strains of M. gypseum complex, composed of 16 from animals and 14 from soils, ere mated with the tester strains of Nannizzia incurvata, N. gypsea and N. fulva. Among 30 strains of M. gypseum complex examined, 16 strains(53.3%) were N. incurvata, 13 strains(43.3%) N. gypsea and 1 strain (3.3%) N. fulva. Among 13 strains of dog isolates, 8 strains(61.5%) were N. incurvata and 5 strains(38.5%) N. gypsea. And each strain isolated from Korean native goat, monkey and albino rat was N. gypsea. Among 14 strains of soil isolates, 8 strains(57.2%) were N. incurvata, 5 strains (35.7%) N. gypsea and 1 strain(7.2%) N. fulva. And -mating type was more frequently observed than +mating type in the strains of N. incurvata and N. gypsea. By this study, N. fulva was isolated the first time in Korea.

• Journal of Korean Institute of Industrial Engineers
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• v.29 no.1
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• pp.49-64
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• 2003

Although assembly sequence planning is an essential task in assembly process planning, it is known as one of the most difficult and time consuming jobs because its complexity is increased geometrically when the number of parts in an assembly is increased. The purpose of this study is to develop a more efficient algorithm for generating assembly sequences automatically. By considering subassemblies, a new heuristic method generates a preferred parallel assembly sequence that can be used in robotic assembly systems. A parallel assembly sequence concept provides a new representation scheme for an assembly in which the assembly sequence precedence information is not required. After an user inputs both the directional mating relation information and the mating condition information, an assembly product is divided into subgroups if the product has cut-vertices. Then, a virtual disassembly process is executed to generate alternate parallel assembly sequences with intermediate assembly stability. Through searching parts relations in the virtual disassembly process, stable subassemblies are extracted from translation-free parts along disassembling directions and this extraction continues until no more subassemblies are existed. Also, the arithmetic mean parallelism formula as a preference criterion is adapted to select the best parallel assembly sequence among others. Finally a preferred parallel assembly sequence is converted to an assembly BOM structure. The results from this study can be utilized for developing CAAPP(Computer-Aided Assembly Process Planning) systems as an efficient assembly sequence planning algorithm.