• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.627-631
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• 2006

The objective of this study was to evaluate the association of genetic differences in the bovine leptin gene and milk yield, reproduction, body condition score (BCS), and plasma glucose level in Iranian Holstein cows. In total, two hundred and thirty eight cows were used and genotyped for a restricted fragment length polymorphism at the leptin gene locus. Two genotypes, AA and AB, have been distinguished which have the frequencies of 0.89 and 0.11, respectively. The genotypes were distributed according to the Hardy - Weinberg equilibrium ($x^2$ = 0.733). During the first 12 wk of lactation, milk yield and composition, live weight, BCS and plasma glucose were measured in 50 cows. Data were analyzed based on a repeated measures ANOVA. During this period, milk yield and composition, live weight, BCS and plasma glucose level were similar among the genotypes. The first cumulative 60-d milk yield, 305-d milk yield, days to first breeding, days open and days from first breeding to conception using previous lactation records were also analyzed using Standard Least Square within mixed models. Fixed effects were year, season, parity and age at calving, and sire. For the reproductive traits the cumulative first 60-d milk yield was also added to the model. Animal was fitted as a random effect. A significant association was detected between the RFLP-AB genotype and 305-d milk yield (p<0.05). The first 60-d cumulative milk yield was similar for the two genotypes (p = 0.21) and tended to be higher in the heterozygous cows. The heterozygous genotypes at the above mentioned locus had a trend to better reproductive performance than the homozygous. The results demonstrate that the RFLP B-allele can yield a higher 305-d milk production with a trend to better reproductive performance.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.11-16
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• 2011

This study was conducted to identify the morphological characteristics and variations level by site environment of native bermudagrass (Cynodon spp.) from costal and island region in South Korea. Soil chemical properties and morphological characteristics were investigated. There were significant differences in plant height, leaf width, leaf length, cotton on leaf blade, stolon, and number of seed per spike depending on where they were collected from natural habitat. We have discovered a variety of variation among the investigated traits in Korean native bermudagrass ecotypes. There were broad leaf and fine leaf types of native bermudgarass in S. Korea. Adaptability was in very high on inadequate environment in bermudagrass with broad leaf types, it has also been suggested that management worth in terms of use. These results may provide basic information for bermudagrass breeding development and the collected types during this investigation would be worth being preserved as genetic resources for further breeding purposes.

• Korean Journal of Medicinal Crop Science
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• v.28 no.1
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• pp.47-55
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• 2020

Background: Curcuma longa L., a perennial crop originating from tropical and subtropical region, including India, is noted for its important medicinal properties. However, C. longa plants are unable to endure the winter season in Korea, and its rhizomes were invariably succumb to fungal infection when stored in polyvinyl bags. In this study, we accordingly sought to develop a C. longa variety capable of producing high rhizome yields and to identify stable conditions under which rhizomes can be stored in Korea. Methods and Results: We evaluated the agronomic characteristics of nine C. longa germplasms and examined the effects of storing rhizomes at different temperatures (4℃ to 24℃) in paper bags or plastic baskets. We found that the finger rhizomes was higher in CUR02, CUR03, and CUR06 germplasms than those of other groups. Furthermore, in terms of yield per 1 ㎡, the weights of the finger rhizomes and tuberous roots were significantly higher in CUR09 (3.4 ㎏/㎡) and CUR04 (678.7 g/㎡) than those of other groups. Therefore, we consider that these C. longa germplasms might be useful as breeding material. Although the fresh weights of the rhizomes were slightly reduced when stored in paper bags and a plastic baskets at 10℃ to 15℃, there was no evidence of fungal decomposition or sprouting, which is observed when using a conventional storage method. Conclusions: The results of this study indicate that the selected C. longa germplasms can provide a useful source of breeding material for the development of high yielding varieties and that a temperature ranging from 10℃ to 15℃ and the use of paper bags or plastic baskets provide stable post-harvest storage conditions for C. longa rhizomes.

• The Korean Journal of Ecology
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• v.22 no.5
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• pp.311-316
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• 1999

Community organization of the drosophilid flies was investigated with respect to the seasonal variation of the species abundance at the natural forests on Mt. Soribong in Kwang-nung (Kyung-Ki Do, Korea) from May to October 1996. The dominant species were Amiota okadai. Scaptomyza pallida, Hirtodrosophila sexvittata. Drosophila bizonata. D. unispina. and D. brachynephros in the annual collection. A. okadai was found with numerically dominance in April and was found in June with less superiority. S. pallida showed their highest peak in occupational in May and after soon they decreased. There was a remarkable increase in the numbers of H. sexvittata in July. This increase may be coincident with the appearance of fungi which provide a breeding site for this species in the forest. On the other hand, D. biauraria and D. triauraria showed their highest peak in May and after soon they decreased, and in September they made the lower peak again. Four species (D. anguraria. D. brachnephros, D. nigromaculata, D. unispina) of qunaria group were found with dominance in August to September. These results suggest that the predominant species in the forest avoid niche overlap by means of seasonal separation of breeding, which is strongly affected by factors associated with season in the deep wooded forests.

• Journal of Ecology and Environment
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• v.36 no.3
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• pp.167-172
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• 2013

A Two-year field experiment was carried out in 2009 and 2010 to evaluate the effects of different densities of wild oat and nitrogen (N) rates on oilseed rape yield and yield components. Experimental design was split plot with three replications. Increased nitrogen rates up to 150 kg N/ha caused an increase in oilseed rape grain yield in weed-free plots (4.26 t/ha; 1t = $10^3kg$), while even at the lowest density of wild oat (15 $plants/m^2$), increasing N fertilizer only up to 50 kg/ha led to a significant increase in grain yield. Wild oat growth was favored by high levels of N. Intraspecific competition reduced biomass, 100-seed weight and number of tillers of wild oat. Both lower N rate and intraspecific competition had negative effect on wild oat growth but the weed was still able to produce a considerable number of tillers and vigorous seeds. It showed that wild oat possess a notable adaptive plasticity and can allocate a greater proportion of its resource toward reproductive organs even under resource shortage conditions and, thus, it may increase the competitive ability of the weed over the crop.Our results suggest that effective weed management should be done to prevent wild oat seed production in crops preceding oilseed rape as well as to control the weed at early season in oilseed rape fields.

• Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.5.1-5.7
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• 2016

The study was conducted to know the cyclic changes in gonadal maturation and to investigate the developmental stages of oocytes and testicular germ cells of an air-breathing fish, Channa striata. Fish were sampled monthly from lentic and lotic environments of three geographical locations of Bangladesh from December to November and the histological analysis of their gonad was done to evaluate the objectives. The highest mean GSI was $5.95{\pm}0.20$ for female in July and $0.14{\pm}0.01$ for male also in July showing that the gonadal development reached its peak during this month. The highest mean oocyte diameter was $1257.50{\pm}24.17{\mu}m$ observed in July implying that the oocyte reached maturity in this month. Histological study of ovary revealed the evidence of early yolk granule stage and late yolk granule stage from April to July. In case of male four stages of spermatogenesis were distinguished and spermatozoa were highly abundant in June and July. So the monthly pooled values of GSI and the analysis of gonadal histology indicated that the peak breeding season of C. striata occurred in July in the lentic and lotic environments. Samples collected from lentic and lotic habitats are suggestive of no difference in the development of the gonad. The results of the present study will be useful for selective breeding programme, conservation and sustainable fishery management of C. striata in its natural habitat.

• Journal of Animal Science and Technology
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• v.54 no.3
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• pp.165-174
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• 2012

For horse breeders or managers, it is critical to understand the estrous cycle of mares. Breeding of mares cannot be successfully achieved throughout the whole year as mares breed seasonally. Mares are only able to breed when day length is more than 16 h, and this period is known as the breeding season. Their estrous cycle is approximately 21 days with 5-7 days of estrus and 14 to 15 days of a diestrus period. The estrous cycle of the mare is mainly controlled by gonadotropins, which control follicular development and ovulation. Mares exhibit unique ovulatory events which are not observed in other species. A LH surge occurs for several days, with levels of LH reaching their peak after ovulation. The LH level at the time of LH peak is lower than most other species. The unique anatomical structure of the ovaries of mares is known to limit the number of eggs ovulated. Several attempts have been made to develop chemical/hormonal agents which might be used to manipulate the timed ovulation of mares. Agents that have been tested include hCG, native GnRH, Deslorelin (Ovuplant, GnRH-agonist), Buserelin (GnRH analogue), equine pituitary extracts and equine chorionic gonadotropin (eCG or PMSG). However, the function, purity or stability of these agents is not reliable. Recombinant equine LH, an alternative agent for the timed ovulation, has been developed and tested for its biological activities, through the use of both in vitro and in vivo experiments. The reLH was suggested to be a reliable agent in inducing ovulation within 48 h after being administered through injection, when the size of dominant follicle is 35 mm in diameter.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2006.10a
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• pp.86-96
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• 2006

To provide some ecological informations for protection and management of mixed heronries, their distribution, breeding species and individuals, and site characteristics that may be important to heron ecology were investigated in Jeollanam-do during 2005 breeding season. During the study, 17 mixed heronries, containing a total of six ardeid species were found. Of them, Great Egret(Egretta alba) and Grey Heron(Ardea cinerea) bred in most sites(both 92%) and were most numerous(36.3%, 31.0% respectively). Many of heronries(53.3%) were located within the bamboo forest. Other site characteristics were as follows: the mean area of heronry was $2346m^2$ with range of $500-7,000m^2$, the mean distance between nearest two heronies was 18.1km with range of 5.6-40.4km, the mean distance to nearest village was 297m with range of 10-2,000m, the mean gradient of the topography was $18^{\circ}$ with range of $2^{\circ}{\sim}40^{\circ}$, and 40.0% of heronries were located in the eastern slope.

• Journal of Animal Science and Technology
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• v.52 no.6
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• pp.481-490
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• 2010

This study was conducted to characterize the morphological and behavior patterns of Sapsaree dogs. The population (n=8,256) has been constructed since 1990 over 12 generations and managed at the Sapsaree Breeding Research Institute, Gyeongsan, Gyeongbuk province. Eighteen morphological and seven behavioral traits were investigated for 882 individuals. Linear models were applied for each trait by fitting sex, season of birth, hair color or test age. The averages of body weight, body length, body height, and depth of chest were $20.5{\pm}2.4\;kg$, $57.3{\pm}4.2\;cm$, $52.1{\pm}3.6\;cm$, and $21.1{\pm}2.4\;cm$, respectively. Males had greater estimated values than females for these body conformation traits. The chocolate Sapsarees had greater averages for body weight, body height and chest depth. The older animals (>2 years) had heavier body weight than younger animals. About 54, 69, 97, 39 and 83.3% of the Sapsarees had hairs with yellow color, straight, medium to long, untangled, and longer around eyes, respectively. Also, about 40% brown eye, 43% curly tail, 78% normal jaw, 86% no missing teeth, 90% no dewclaw, and >90% with black nose, pendent ear, tongue without spots were observed. About 95% males were normal in testicles state. The males performed significantly better than the females for majority of the behavioral traits. For nerve stability, affability, wariness, adaptability, sharpness, activity, and reaction during blood drawn about 79%, 73%, 76%, 61%, 70%, 48% and 81% of the Sapsarees performed at desired level. In general, the Sapsarees showed good characteristics for both morphological and behavioral traits, which can be exploited to use the Sapsaree breed as a companion or guide dog.

• Korean Journal of Medicinal Crop Science
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• v.28 no.4
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• pp.298-309
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• 2020

Background: Safflower (Carthamus tinctorius L.) is a useful medicinal and oil crop in Korea. However, when safflower is cultivated, the flowering period overlaps with the rainy season, and seed maturation is poor. Therefore, this study aimed to use basic research data to develop superior varieties using agronomic characteristics and crossing method. Methods and Results: A total of 34 safflower germplasms were sown and their agronomic characteristics were investigated. Based on these investigations, the cultivar 'ui-san-hong-hwa' was selected as the mother plant, and 'Myanmar safflower' (Hsu Pan) was selected as the father plant. In addition, we developed a floret-protecting cap to cover florets after emasculation during the artificial crossing. When florets were protected by the cap, the seed setting rate increased in comparison to that in the non-covered florets. Conclusions: Agronomic characteristics can contribute to developing suitable varieties. The results suggest that the protection cap will be helpful in breeding without the floral organ drying. This study contributes an efficient breeding method to develop new safflower varieties.