• 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 Veterinary Service
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• v.26 no.2
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• pp.151-156
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• 2003

This study was carried out to get a fundamental information for improvement of reproductive performance in gilt. We investigated the effects of breeds on body weight, age, body length, wither's height, girth and backfat thickness, and the serum concentrations of estradiol-17${\beta}$, cortisol and progesterone at first estrus and mating of gilts. A total of 47 gilts of Duroc, Landrace and Yorkshire, produced at Livestock Experiment Station, Chungnam livestock sanitation research institute from 2000 through 2002, were used for this experiment. Body weight, age and girth of Duroc at frist estrus and mating were higher than those of Landrace and Yorkshire. There were no differences on body length among the three breeds at frist and mating. Wither's height of Duroc and Yorkshire at first estrus and mating was higher than that of Landrace. Backfat thickness of Yorkshire was thinnest among the three breeds at first estrus, but there were no differences on backfat thickness among the three breeds at first mating. Serum estradiol-17${\beta}$ concentration of Landrace(45.0 pg/ml) at first estrus was higher than that of Yorkshire(27.4 pg/ml) and Duroc(21.8 pg/ml), but there were no differences on estradiol-17${\beta}$ concentration (from 18.5 to 31.9 pg/ml) among the three breeds at first mating. Serum cortisol concentration of Duroc at first esturs and mating was higher than that of Landrace and Yorkshire. There were no differences on serum progesterone concentration among the three breeds at first estrus and mating of gilt.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.113-119
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• 2007

Tropical tasar silkmoth Antheraea mylilta D. is an economically important insect. The wild nature and above all unsynchronized emergence of moths lead to impairment in reproductive activity. The mating in moths is low (64%-70%), leaving about 30-36% of potential females unused for seed (= egg) production. Delay in mating adversely affects the reproductive performance such as mating behaviour, fecundity and fertility. Females are more severely affected by mating delay than males. Therefore, a study was under taken to develop a method to overcome the problem so that the production of layings can be increased to meet the ever increasing demand. It was revealed from the study that out of 16 possible age combinations (from the age groups of day 0 to day 3), female and male of day 0 (4-8 hours old) excel in their reproductive performance than others (with 94.4% mating success, 284 fecundity and 91.5% hatching). Reproductive performance declined significantly even if one of the parents was older. When either of the mating pair was 1 day old, the mating declined by 28%; fecundity by 32.8%; and hatching by 40.8%. The insemination of eupyrene sperm was declined by 35.2% when both the parents are 1 day old. Mating duration of 8 hours resulted in insemination of $8.3{\times}10^5$ eupyrene sperms, which was declined by 31.6%, 48% and 55% upon lowering of mating duration to 6 hr, 4 hr and 2 hr were maintained respectively.

• Korean Journal of Veterinary Research
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• v.15 no.2
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• pp.215-222
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• 1975

Infertility and breeding status of Korean cows which are reared in a extensive alpine ranches of Daegwanryeong area was investigated. The results obtained were summarized as follows, 1. Infertility frequency of the cows was 25.9% against a total examined number of 675 heads, and was 17.6% against a total rearing number. 2. The distributions of infertile cows 44.6% of Granular vaginitis-like syndrome, 36% of repeat breeder, 8.6% of symptom of ovary, 6.8% of symptom of uterus and 4% of other symptoms. 3. According to its age were found by 51.4% upon 2 years of age, 30.3% upon 3 years of age, 11.4% upon 4 years of age and 6.9% upon S years of age. 4. Breeding status of Korean cows showed 74.1% of conception rate in the cases of pre-treatment, while breeding status increased markedely in the cases of post-treatment by the 85.8%. 5. The conception rate by the artificial insemination mainly on the first mating was 36.1%. on the second mating 23.0% and on the third mating 18.0%. Total conception rate between first and third mating was 77.1%. 6. The therapeutic effect by treatment for granular vaginitis-like syndrome was 87.1%.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.2
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• pp.87-94
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• 2005

Mating is an essential behavioural social event in the life cycle of silkworm, Bombyx mori (L.) for the perpetuation of population. A number of intrinsic and extrinsic factors and events of significant importance are involved in successful mating and egg deposition by an adult silk moth which besides biochemical, physiological and environmental factors also includes attraction of reproductively competent male and female moth for mating, duration and frequency of mating, age of moth at the time of mating, reuse of male moth in the production of eggs etc. An attempt has been made in this review article to elucidate briefly the behaviour of male towards female moth after eclosion, impact of duration and frequency of mating on egg deposition and oviposition, reuse of mated male moth in the production of quality and quantity eggs etc. in the silk-worm, B. mori and its significance in silkworm seed production.

• Korean journal of applied entomology
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• v.52 no.3
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• pp.249-253
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• 2013

The adzuki pod worm, Matsumuraeses phaseoli (Matsumura) is an insect pest that attacks the flowers and pods of Vigna angularis. The circadian rhythms of eclosion and mating, and the effects of age and antenna ablation on mating success, were investigated. With a photoperiodic regime of 16:8 (Light:Dark) h, most adult eclosion was observed within 4 h after lights-on. Most adult mating was observed during the scotophase, although some occurred within 2 h after lights-on. However, the adults did not copulate on the day of emergence. The mating rate increased with adult age: being higher in the 4-d-old adult pairs than pairs of lower age. Most of the antennectomized males or females did not copulate with normal individuals of the opposite sex.

• Korean Journal of Animal Reproduction
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• v.16 no.3
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• pp.261-267
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• 1992

The reproductive performance of SPF ICR mice under single paired mating were examined to get reproductive background data and to establish single paired rotational mating system. The results obtained were as follows : average litter size was 15.4$\pm$2.0 heads ; average weaning rate was 95.7$\pm$4.9% ; sex ratio(male/female) was 1.09$\pm$0.26 ; aveage delivery interval was 23.0$\pm$2.4 days. It was given the largest litter size at the age of 121~150 days and in 2nd~4th parities, but at the age of under 90 days and in 1st parity weaning rate and delivery interval were higher and shorter than those of the other ages and parities, respectively. In sex ratio, the number of male litters was slightly increased from that of female litters. The weaning rate of litters from dams which nuresed 12 litters was the highest among those of different litter sizes, and it was decreased dependent upon increment of litter size. There were no difference among 4 groups for reproductive performance, therefore the present study could have important sources for animal breeders who produce mice using the single paired rotational mating system.

• Korean Journal of Animal Reproduction
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• v.27 no.2
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• pp.163-167
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• 2003

This study was carried out to get a fundamental information fur improvement of reproductive performance in gilt. We investigated the effects of breeds on body weight, age, body length, wither's height, girth and backfat thickness, and the serum concentrations of estradiol-17$\beta$, cortisol and progesterone at first estrus and mating of gilts. A total of 47 gilts of Duroc, Landrace and Yorkshire, produced at Livestock Experiment Station, Chungnam Livestock Sanitation Research Institute from 2000 through 2002, were used for this experiment. Body weight, age and girth of Duroc at first estrus and mating were higher than those of Landrace and Yorkshire. There were no differences on body length among the three breeds at first estrus and mating. Wither's height of Duroc and Yorkshire at first estrus and mating was higher than that of Landrace. Backfat thickness of Yorkshire was thinnest among the three breeds at first estrus, but there were no differences on backfat thickness among the three breeds at first mating. Serum estradiol-17$\beta$ concentration of Landrace (45.0 pg/ml) at first estrus was higher than that of Yorkshire (27.4 pg/ml) and Duroc (21.8 pg/ml), but there were no differences on estradiol-17$\beta$ concentration (from 18.5 to 31.9 pg/ml) among the three breeds at first mating. Serum cortisol concentration of Duroc at first estrus and mating was higher than that of Landrace and Yorkshire. There were no differences on serum progesterone concentration among the three breeds at first estrus and mating of gilt.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.5
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• pp.419-425
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• 1995

Twenty growing female Damascus (Shami) goats and twenty growing Chios ewes of two mating ages (10 and 12 months) were used to study the effect of mating age (MA) on reproductive performance (RP). In addition to (RP), The growth, milk production and nutrient requirements were also evaluated. A complete random design in a $2{\times}2$ factorial was used, with (MA) and species as the main factors. (MA) had no effects on (RP), milk production and mortality. No significant difference (p > 0.05) were observed between (MA) or between species, for age at kidding/lambing (K/L). Sheep reached puberty earlier than goats. Average age (months) at conception and at (K/L) was 15.8; 20.8 and l7.0; 22.0 for sheep and goats respectively. Body weight (BW), rather than age was the most important factor determining puberty. Both goats and ewes conceived when they reached about 67% of their mature (BW) for goats and 85% for ewes. Sheep grew faster than goats, but the latter had higher twinning (67.8% versus 25%). Chios sheep were suitable for meat and Shami goats for dairying or dual purpose systems. Nutrient requirements for growth of goats and ewes were similar with an average DM-intake of about 4% (BW); 12-13% CP and 65-69% TDN (DM-basis) of the total ration. It is recommended to breed Chios ewes at a (BW) of at least 50 kg and Shami does at 38 kg, irrespective of their age.