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Productivity Affected by Various Disease Conditions in Bovine (소의 질병감염이 생산성에 미치는 영향)

  • 이성재;이후식;노수일;김길수;이주묵
    • Korean Journal of Veterinary Service
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    • v.17 no.3
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    • pp.227-246
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    • 1994
  • Present investigations were undertaken in order to clarify the clinical status of Korean native cattle and dairy cattle(holstein). Blood, Feces and urine samples were collected from 247 Korean native cattle(222 adult and 25 calf), 224 dairy cattle(211 adult and 13 calf) at Chonbuk area and analyzed for clinical, serum chemical, hematological and urinary findings. In addition, we were examined the infection rate of Theileriosis, internal patasite and ring worm. The mean value for each component was calculated by statistical analysis using Excel computer program. From these investigations the following results were obtained. The mean values for RBC, PCV and etc in 433 adult cow(Korean native cattle and dairy cattle) were similar with other reports. But the mean values for MCHC of all species were lower than normal. Adult Korean native cattle and adult dairy cattle which showed hematologically normal levels were only 9.01% and 9.48%, respectively. Ahnormally high values for PCV, RBC and Hb were recorded in 7.66% of adult Korean native cattle, 20% of Korean native calf, 15.38% of dairy calf. Adult Korean native cattle and adult dairy cattle which showed hematologically anemia were 4.95% and 19.43% respectively, but all in Korean native calf and dairy calf showed normal values. Adult Korean native cattle, adult dairy cattle, Korean native calf and dairy calf which showed normal serum protein level were 84.0%, 90.8%, 50% and 44.4%, respectively. In present investigations, 50% of Korean native calf and 55.6% of dairy calf were decreased serum protein values under normal range. These abnormally decreased serum protein values mean the shortage of antibody, and these have a possibility to occrus to pneumonia and diarrhea. From these results, the economical loss caused by pneumonia was calculated as 124, 038, 833 won in the KNC and 742, 703, 430 won in the dairy calf rearing in Chonbuk area. Calculated economical loss caused by enteritis was 56, 658, 690 won in Korean native cattle. 476, 775, 799 won in dairy calf and the total loss amount to 533, 434, 488 won in Chonbuk area. Abnormally high values($21.7{\pm}4.0mg/dl) for serum calcium were recorded 49.6% in dairy cattle. The mean values of serum total cholesterol were $170.8{\pm}99.8mg/dl in Korean native cattle, $196.0{\pm}40.6mg/dl$ in Korean native calf, $202.9{\pm}86.0mg/dl$ in adult dairy cattle and $289.4{\pm}97.5mg/dl$ in dairy calf. The infection rate of internal parasite were as follows; adult Korean native cattle:21.2%, Korean native calf:80%, adult dairy cattle:67.8%. The estimated economical loss caused by internal parasites infection were 1, 120, 855, 837 won in Korean native calf, 4, 994, 959, 405 won in adult Korean native cattle, 3, 334, 751, 066 won in adult holstein, and the total loss amount to 9, 450, 566, 308 won. The infection rate of theileriosis were 1.4% in Korean native cattle and 6.6% in dairy cattle. The presumed Economical loss by T. sergenti infection were 154, 408, 482 won in Korean native cattle and 171, 577, 237 won in dairy cattle rearing at Chonbuk area. The infection rat of ringworm were 0.5% in Korean native cattle, 0.9% in adult dairy cattle and 7.7% in dairy calf. The presumed economical loss by dermatomycophyte were 12, 061, 532 won in Korean native cattle, 16, 895, 403 won in dairy cattle, and the total estimated loss amount to 28, 955, 935 won a year in Chonbuk area. The infection rate of ringworm were 0. 5% in Korean native cattle, 0.9% in adult dairy cattle and 7.7% in dairy calf. The presumed economical loss by dermatomycophyte were 12, 061, 532 won in Korean native cattle, 16, 895, 403 won in dairy cattle, and the total estimated loss amount to 28, 955, 935 won a year in Chonbuk area.

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Genetic Expression of Color Approved by Color Qualities of Munsell System on the Cocoon of Silkworm, Bombyx mori (누에 고치색 유전자 발현의 다양성 검정 및 색채과학적 해석)

  • Han, Myung-Sae;Park, Hyun-Ro;Han, Sang-Mi;Nam, Ki-Soo;Kwon, Soon-Ha;Lim, Jong-Sung;Nguyen, Mau Tuan
    • Journal of Sericultural and Entomological Science
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    • v.41 no.1
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    • pp.20-28
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    • 1999
  • Color qualities investigated on the basis of Munsell code and Korean standard color code for the cocoons from various strain of mulberry silkworm, Bombyx mori. 16 of different color qualities were identified from 21 of original silworm strains, and determinated international name with the revision of Korean color name for cocoon. The various cocoon color confirmed on the sphere from 567 to 593 nm wavelength, 78% of those located at the region about 580 nm (575~584) of sensitive "color difference limen". Y gene engaged broad ranges of wavelength (575~593 nm) in the color expression, by contrast with other genes of Pk (593 nm), F (584~593), Grc and relative G group (567~570 nm), on the transmission of carotenoid or flavonoid color substance. YC gene expression by original silk worm strain was also distinguished by those variation of specific yellow than other colors from Grc, GaGb, Gc, and YPkF. Appearance of chrome yellow cocoon was dominant than other yellow in the cross among vivid yellow group. F1 of pin${\times}$green produced the cocoon of yellow such as "additive mixture" as color light, however, most of the hybrid between yellow cocoon showed the color similar to "subtractive mixture" as a mixture of dyestuff. Hybrid cocoons among yellow or green colors were decreased their hue, value, and chroma, than those of parent. Diallel cross among the strain of various green cocoon suggest the existence of Grc, Ga, Gb, Gc genes. Cream colored cocoon of B. mandarina was differed from other yellow cocoon of Bobyx mori B. mori. Y$^A$ with Ymc showed the similar role of Y with C, therefore, segregated yellow cocoon from the B. mori${\times}$B. mandarina (+$^YC/Y^AYmc$). YC expression of $Y^AY$mc genes might be suppressed by deficiency of outer layer sericin on the middle division of silk giand in the B. mandarina.

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Studies on the Seroepidemiology of Helminthic Diseases in Korea (우리나라의 주요 기생충질환(寄生蟲疾患)에 대한 혈청역학적(血淸疫學的) 조사(調査))

  • Rim, Han-Jong;Lee, Joon-Sang;Joo, Kyoung-Hwan;Chung, Myung-Sook
    • Journal of agricultural medicine and community health
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    • v.16 no.1
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    • pp.48-60
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    • 1991
  • In a seroepidemiological study in several areas of Korea, the ELISA technique was performed to determine prevalence of some important helminthic diseases in our nation during March $15^{th}$ to June $30^{th}$. 1991. In this survey the serum antibody positive rates of anisakiasis, toxocariasis, clonorchiasis, paragonimiasis, cysticercosis, and sparganosis were measured. Among, 6,704 cases examined, 19.7% showed positive antibody titer at least one of the six items studied. Overall positive antibody rate was 8.1% in anisakiasis, 5.6% in toxocariasis, 3.6% in clonorchiasis, 1.7% in paragonimiasis, 4.5% in cysticercosis, and 2.6% in sparganosis respectively. In Pusan port southeastern part of Korea, antibody positive rate of anisakiasis was 2.9%, and clonorchiasis was 2.8% among 450 examine. In TaeJ$\check{o}$n city, central part of Korea. toxocariasis(6.7%) and anisakiasis(3.7%) showed high serologic positive rate. Of the 875 persons in Chunche$\check{o}$n gun(=province), northern central rural area of South Korea, anisakiasis was revealed as 3.4% seropositivity. In Tonghae port, eastern coast of South Korea. 9.9% of population examined showed positive antibody titer in anisakiasis. Of the 1,122 persons examined in Southern part of Cholla-Namdo(Southwestern coastal area of Korea), anisakiasis was 16.9%, cysticerocosis was 12.7% and the paragonimiasis was 3.3% respectively. In some localized area of Cholla-Pukdo, anisakiasis was 9.3% and cysticekosis was 4.3% among 702 cases examined. In some localized area of Kyungsang-Pukdo, anisakiasis was 10.6%. and toxocariasis was 16.1% among 900 cases examined. And finally, in Cheju-do, southern island of Korea, anisakiasis showed high positive rate(6.7%). Because cross reactions between related helminth group may disturb the analysis of these data, use of further developed techniques such as EITB(enzyme-linked immunoelectrotransfer blot) was considered as a essential tools for the study. We thought that probably most of the positive cases of cysticerosis were taeniasis cases. We can't rule out taeniasis even though EITB was employed as far as crude worm extract or cystic fluid of cysticercus was used as antigen. It was well Known that toxocariasis and anisakiasis also showed cross reactivity. However, the data presented here focus on seropositive rate of several helminthic diseases in Korea, not true prevalence rate of helminthiases, and to wait for more expensive purified antigen in sufficient amount for epidemiologic use is not necessary because increased immunologic sensitivity had little effect on epidemiologic sensitivity. We, here, suggest that ELISA should be applied as soon as possible to the evaluation of prevalence of tissue invading parasitic diseases, and a review of the antibody positive rate obtained in this study would be a basic data for controlling program of parasitic diseases in Korea.

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An epidemiological study of metagonimiasis along the upper reaches of the Namhan River (남한강 상류의 Metagonimus 유행에 대한 연구)

  • Chai, Jong-Yil;Huh, Sun;Yu, Jae-Ran;Kook, Jin-A;Jung, Kyung-Chun;Park, Eun-Chan;Sohn, Woon-Mok;Hong, Sung-Tae;Lee, Soon-Hyung
    • Parasites, Hosts and Diseases
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    • v.31 no.2
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    • pp.99-108
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    • 1993
  • An epidemiological study of Metogonimus infection was undertaken along the upper reaches of the Nmhn River, with special consideration on the species (type) of the worms collected from humans. Eggs of Metogonimus spp. were detected from 15 (9.7%) of 154 people examined in Umsong-gun, and from each Infected person (5 cases) 6.015- 24,060 worms (mean 13,2331 were recovered after treatment with praziquantel (10 mg/kg). Eggs were also detected from 37 (48.1% of 77 people In Yongwol-gun, from whom (27 casesl 1-4,965 worms (mean 1,2151 were collected. The worm from Umsong-gun consisted of both Metagonimus Miyata type and Metagonimus takohashii, whereas those from Yongwol-gun consisted of only Metqsonimus Miyata type. When the uterine eggs of the two kinds and M. yokogawoi (obtained from people In Tamjin River basin) were morphologically compared, it was suggested that the egg size should be a good Indicator for discrlmination of the species or type. The source of human Infection was proved to be fresh water fleshes: 49 of 52 Znsco plntvpus examined, 6 of 8 Hemibcrbus loniroskis, 13 of 15 Pseunogobio esuinl:, 4 of 6 Odontobutis obscura intemfptn, and 17 of 18 Corqssiw carassiw were found Infected with Metosonimw metacercariae. From the results, it is concluded that the upper reaches of the Namhan River are endemic foci of Metogonimn Miyata type and M. takahashii.

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Effect of Beta-glucans Extracted from Phellinus baumii on the Growth of Caenorhabditis elegans (예쁜꼬마선충의 생육에 관한 장수상황버섯의 베타글루칸 함유 추출물의 영향)

  • Kim, Hye-Min;Lee, Dong-Hee
    • The Korean Journal of Mycology
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    • v.40 no.1
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    • pp.54-59
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    • 2012
  • This study investigates the effect of ${\beta}$-glucans on the growth of Caenorhabditis elegans. Comparison was made among lipopolysaccharide (LPS) and ${\beta}$-glucans extracted from Phellinus baumii, in the presence of peptidoglycans which is available as the major carbon source from OP50, a non-pathogenic strain of Escherichia coli. When the three sources of carbohydrate were added singularly or in mixture to the culture media, a significant level of variation was observed with respect to fecundity. Addition of ${\beta}$-glucans appeared to increase the fecundity. When ${\beta}$-glucans was reinforced in the culture media, the fecundity increased at least 20 percent compared to the OP50-only media which exclusively contains peptidoglycans. In terms of life span, C. elegans showed a modest reduction when treated especially with ${\beta}$-glucans. C. elegans accumulated less fat in the ${\beta}$-glucans containing media different from the OP50 media. Based on the Sudan black staining, fat deposition significantly decreased corresponding to the ${\beta}$-glucans content in the media. On LPS-supplemented media, no difference was observed in fat deposition compared to the normal OP50 media. At the level of motility, ${\beta}$-glucans-treated worms moved more distance as well as LPS-treated worm. They also showed a comparable degree of motility under similar treatment with each source of carbohydrate. In conclusion, LPS and ${\beta}$-glucans, extracted from P. baumii, may not entirely replace the food required for C. elegans; however, it might be utilized as valuable alternative food source which C. elegans use as forms of carbohydrates in stead of peptidoglycan of OP50.

Physioanatomical studies on mechanism in the process of becoming non-spinning silkworm(Bombyx mori) (토사불능잠의 출현기구에 관한 생리해부학적 연구)

  • 윤종관
    • Journal of Sericultural and Entomological Science
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    • v.8
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    • pp.41-50
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    • 1968
  • In order to achieve efficiency of laying eggs of silkworms, it is very important to eliminate noncocooning silkworms. This study is written on the basis of observation and analysis of mechanism of silkworms physiologically and anatomically. It is hoped that given herein will contribute to the effecting elimination work. Outline of the study summarize as follows: 1. It is observed through microscope that the silkworms which are seen normal state in the silk gland but no ability of cocoon making have polyhedrosis in the nerve, trachea and muscle near the tissue of the spinneret. 2. Relatively high proportion of non-cocooning silkworms are caused by the grasserie of the silkworms. 3. As a result of inoculation with purulent discharges against silkworms from first fooding through 8th day of 5th instar, number of cocooning silkworms were increased when inoculation are applied at laterer day of the instar. In the case of non-cocooning silkworms, meanwhile, resulted not big varriation when it is apllied in the early and middle of the period, but number of non-cocooning silkworm was reduced when the inoculation are given at laterer of the instar. Number of death during rearing and mounting are increased when earliest application of inoculation are carried out. 4. Symptom of grasserie was appeared more or less three days after application of the inoculation. Some silkworms which were inoculated just before mounting has ability of cocooning making even taken grasserie, in this case the silkworm can make thin cocoon. since the silkworm fall sick during cocoon making and unable of spinning soon. when the worm was affected by grasserie slightly, it was observed that the silkworm can spinning. It is supposed to be the light paralysis of spinneret is not very much influenced to spinning. 5. As a result of observation of original stock and hybrid including other 44 kinds of silkworm, many non-cocooning silkworms were found in the original stock especially originated from japanese than in hybrid. 6. A number of undulations are found in the middle division of the silk gland of non-cocooning silkworms. 7. According to the observation of the sizes of the body and digestive organs, normal natured silkworms and non-cocooning silkworms are more or less same in length, but the width, circumference of bodies and digestive organs were more larger in the later. If silkworm which was in the period of active eating of 5th instar was given shock of dropping to the floor, the silkworm receives little more shock when hit to side of the body than to head, and concrete floor than ondol and wooden floor.

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Project to increase productivity of livestock in Honam area against UR (호남지역의 양축농가에 있어서 UR에 대처한 가축의 생산성 향상에 관한 연구)

  • Lee, Joo-mook;Kwon, Oh-deog;Chae, Joon-seok;Kim, Myeong-chul;Kim, Heung-seob;Lee, Sung-jae;Lee, Hoo-sik;Roh, Soo-il;Kim, Kil-soo
    • Korean Journal of Veterinary Research
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    • v.34 no.1
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    • pp.195-212
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    • 1994
  • For the purpose to increase productivities of livestock the present investigations were undertaken in order to clarify the clinical and suclinical status of Korean native cattle, dairy cattle(holstein) and Korean native goat. Blood, feces and urine samples were collected from 247 Korean native cattle(222 adult and 25 calf), 224 dairy cattle(211 adult and 13 calf) and 142 Korean native goat rearing at Chonbuk area and analyzed for clinical, serum chemical, hematological and urinary findings. In addition, we were examined the infection rate of theileriosis, internal parasite and ring worm. The mean value for each component was calculated by statistical analysis using Excel computer program. From these investigations the following results were obtained. The mean values for RBC, PCV and etc in 433 adult cow(Korean native cattle and dairy cattle) were similar with other reports. But the mean values for MCHC of all species were lower than normal. Adult Korean native cattle and adult dairy cattle which showed hematologically normal levels were only 9.01% and 9.48%, respectively. Abnormally high values for PCV, RBC and Hb were recorded in 7.66% of adult Korean native cattle, 20% of korean native calf, 15.38% of dairy calf and 13.36% of Korean native goat. Adult Korean native cattle and adult dairy cattle which showed hematologically anemia were 4.95% and 19.43% respectively, but Korean native calf and dairy calf showed normal. Adult Korean native cattle, adult dairy cattle, Korean native calf and dairy calf which showed normal serum protein level 84.0%, 90.8%, 50% and 44.4%, respectively. In present investigations, 50% of Korean native calf and 55.6% of dairy calf were decreased serum protein values under range. These abnormally decreased serum protein values mean the shortage of antibody, and these have a possibility to occurs to pneumonia and diarrhea. From these results, the economical loss caused by pneumonia was calculated as 124,038,833 won in the KNC and 742,703,430 won in the dairy calf rearing in Chonbuk area. Calculated economical loss caused by enteritis was 56,658,690 won in Korean native cattle, 476,775,799 won in dairy calf, and the total loss amount of 533,434,488 won in Chonbuk area. Abnormally high values$(21.7{\pm}4.0mg/dl)$ for serum calcium were recorded 49.6% in dairy cattle. The mean values for serum total cholesterol were $170.8{\pm}99.8mg/dl$ in Korean native cattle, $196.0{\pm}40.6mg/dl$ in Korean native calf, $202.9{\pm}86.0mg/dl$ in adult dairy cattle and $289.4{\pm}97.5mg/dl$ in dairy calf. The infection rate of internal parsite were as follows; adult Korean native cattle: 21.2%, Korean native calf: 8.0%, adult dairy cattle: 67.8% and Korean native goat: 81.5%. The estimated economical loss caused by internal parasites infection were 1,120,855,837 won in Korean native calf, 4,994,959,405 won in adult Korean native cattle, 3,334,751,066 won in adult holstein, and the total loss amount to 9,450,566,308 won. The infection rate of theileriosis were 1.4% in Korean native cattle and 6.6% in dairy cattle. The presumed economical loss by T. sergenti infection were 154,408,482 won in Korean native cattle and 171,577,237 won in dairy cattle rearing at Chonbuk area. The infection rate of ringworm were 0.5% in Korean native cattle, 0.9% adult dairy cattle and 7.7% in dairy calf. The presumed economical loss by dermatomycophyte were 12,061,532 won in Korean native cattle, 16,895,403 won in dairy cattle, and the total estimated loss amount to 28,955,935 won a year in Chonbuk area.

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Identification and prevalence of trematode(Gen Azygia) and nematode(Gen Pingus) in Ophicephalus argus (가물치의 위장내 기생하는 흡충(Azygia속) 및 선충(Pingus속)의 동정과 감염상황)

  • Moon, Moo-hong;Lee, Eun-woo
    • Korean Journal of Veterinary Research
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    • v.38 no.1
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    • pp.147-159
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    • 1998
  • A survey of the internal parasites in 115 fishes of Ophicephalus argus was carried out in Kyungpook province during the period from January 1995 to November 1997. A species of trematode from the stomach and a species of nematode from the caeca of the fishes was discovered respectively. The trematode was identified as Azygia hwangtsinyi (Tsin, 1993) and the nematode as Pingus sinensis ($Hs\ddot{u}$, 1993). The fluke was pressed at thick of 0.1mm~0.2mm between slide glasses and fixed in 70% ethyl alcohol solution. The fluke was washed with tap water after fixation and stained with hematoxylin-carmin and mounted in balsam through routine methods. The nematode was fixed in 5% formalin solution and mounted with lactophnol or glycerine jelly. Morphology : Arygia hwantsinyi ; The fluke is elongate body with approximately parallel margins and rounded extremities in pressed preparations(Fig 1). The cuticle is unarmed. The oral sucker is ventro-subterminal in position. The ventral sucker is slightly smaller than oral sucker and positioned at 14.2% of body length from the oral sucker. The cirrus sac and genital pore is in mid-ventral line, slightly anterior to the ventral sucker. The oral sucker is succeeded by a well developed muscular pharynx. It is succeeded by a short inverted Y-shaped oesophagus. The inner wall of oesophagus is consisted of many fine folded membrane. The fine tubes of esophagus pass into the intestinal heads which are distended and presented a marked borderline between the fine tube and intestinal heads. The Intestinal heads start at level of pharynx and pass caudad in a zigzag course to end quite near caudal margin. The uterine coils occupy the intercecal area between the level of the cephalic margin of the ovary and about the level of the ventral sucker. The uterus is filled with many eggs. The testes are round or oval and placed one behind the other generally a little diagonally. The posterior testis is placed at level of 75.1% of body length. The ovary is oval, placed ahead the anterior testis. The shell gland not discernible outline is contacted with ovary ahead it. The vitelline glands are consisted of small oval vesicles. The vesicles occupy extracecal regions and between a little posterior of the ventral sucker and near caudal margin. Pingus sinensis : Female ; The cuticle is smooth and the cervical alae are well developed. The mouth opening is small, triangular, and without lips. The anterior end bears four sub-medial papillae. The oesophagus is divided into a muscular and glandular portion. The nerve ring is situated just at the junction of the muscular and glandular portions of the oesophagus. The vulva which has a prominent flap, is placed behind the middle of the body about one-third of the length of the worm from the posterior extremity. The vagina is strongly muscularised and after running anteriorly about $68{\mu}$, divides itself into two broad uterine tubes with an anterior and a posterior one. There are a few eggs in the uterine tubes. The tail is slender, straight and pointed. The ovary extends almost to the posterior extremity. Male : Male is smaller than female. The tail is pointed, curved and carrying well-developed caudal alae. A prominent muscular precloacal sucker is characteristic. The spicules are equal and short. There are four pairs of pedunculated pre-anal papillae, of which the most anterior pair are situated just at the level anterior to the muscular sucker. Two pairs of pedunculated papillae are present before the anus. There are five pairs of post-anal papillae of which the most anterior pair and the second counted from the posterior end are ventral and more marked than the ones which are situated laterally.

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Effects of N. P. K. and sugar contents of different host-plants on the Biology of the fall web-worm, Hyphantria cunea DRURY (기주식물의 N.P.K. 및 Sugar의 함량이 흰불나방에 미치는 생물학적 영향)

  • Chung K. H.;Choi S. Y.
    • Korean journal of applied entomology
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    • v.5_6
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    • pp.39-46
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    • 1968
  • This experiment was conducted to study the effects of nitrogen, phosphorus, potassium, and sugar contents in the loaves of five different host plants on tile larval period, pupal period, pupal period, number of eggs in the ovary, and the tolerance of fall webworm larvae (Hyphantria cunea DRURY) to gamma-BHC. The results obtained in this study were as follows; 1. The contents of nitrogen, phosphorus, potassium, and sugar in tile leaves tested were varied with the species of the host plants and sampling time. 2. The larval and pupal periods were also varied with the host plants and generation of the fall webworm. The shortest larval and pupal periods were found in the mulberry and the longest ones in the apple tree, and their periods were shortened much more in the second generation. Except the relation between the larval period and tile nitrogen content in the first generation, significant correlation could not be found between their periods and nitrogen, phosphorus, potassium and surgar contents. The nitrogen contents among the other chemical factors, however, might be much more influenced on their developing period. 3. The pupal weight and number of eggs in the ovary were also varied with the host plants. sex, and generation. In both generations, the greatest pupal weight and number of eggs per female were found in the mulberry and the least ones in the apple tree. No significant correlation could be found between the pupal weight and number of eggs per female and the chemical factors analyzed. However, only the nitrogen content seemed to be highly related to the pupal weight and number of eggs. 4. The tolerance of the fall webworm larval to gamma-BHC was highly varied with the host plants. The host order o( the larval tolerance level to gamma-BHC was box-elder, popla, platanus, apple tree, and mulberry. There was no significant correlation between the larval tolerance to the BHC and the chemical factors analyzed. However, the larvae fed on the host plant with higher pottassium content were shown a tendency to be higher tolerant.

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Reproductive Cycle of the Echiuroid Worm Urechis unicinctus(von Drasche) in Southern Korea (한국산 개불, Urechis unicinctus (von Drasche)의 생식주기)

  • 최상덕;김호진;이원교;곽은주;윤호섭;라성주;이인곤
    • Journal of Aquaculture
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    • v.13 no.2
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    • pp.169-174
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    • 2000
  • Reproductive cycle of U. unicinctus was studied from September 1998 to August 1999, using gonadosomatic index (CSI) as an indicator. In November, the CSI values were maximum for male (6.2) and female (7.0), respectively; the values were lowest for them (1.0 and 0.5) during the successive february. Subsequently, they rapidly increased and attained peak by March-April. The values decreased again in both sexes and remained unchanged until August. The index increased in October to attain the peak by November. The CSI values clearly indicated that there are two spawning events in a year, namely the first one during April-May and the second one in December. Reproductive cycle was classified into the following successive stages: in female, multipication (January~February, June ~Setember), maturation (March~April, November), spent (May and December), degeneration and resting (June and January), and in male, multiplication January ~ february, June ~September), maturation (March~April, October~November), spent (May and December) and degeneration and resting (January and June). Histological observations revealed that oocytes in the ovary matured simultaneously in November and March. At the same time, the envelopes of matured testis became thinner than those in the early stage.

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