• Title/Summary/Keyword: Natural mortality rate

Search Result 125, Processing Time 0.023 seconds

Fodder Productivity and Growth Persistency of Three Local Cassava Varieties

  • Tung, C.M.;Liang, J.B.;Tan, S.L.;Ong, H.K.;Jelan, Z.A.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.14 no.9
    • /
    • pp.1253-1259
    • /
    • 2001
  • Three cassava varieties, namely MM 92 (MM), Black Twig (BT) and Local (LC), were arranged in a randomized complete block design to evaluate their dry fodder and crude protein (CP) productivity as well as growth persistency. Cassava plants grown in small plots of $5m{\times}10m$ at a planting distance of $25cm{\times}25cm$ were harvested every 6 weeks starting from 3 months after planting. Dry fodder yields of MM, BT and LC over the 8 harvests were 8.55, 8.01 and 6.15 t/ha, respectively. All varieties produced more leaves than stems with average leaf:stem ratios of 5, 5.9 and 4.8 for MM, BT and LC, respectively. In terms of CP production, MM was the highest yielder (272 kg/ha/harvest), followed by BT and LC (238 and 184 kg/ha/harvest, respectively). The total accumulative CP amounts over the 8 harvests were 2179, 1903 and 1474 kg/ha for MM, BT and LC, respectively. The mortality rates were 9.91, 14.01 and 13.98% for MM, BT and LC, respectively. Phosphorus content was more stable than potassium content during defoliation. MM, BT and LC had whole plant phosphorus contents of 0.41, 0.41 and 0.39%, respectively; whole plant potassium contents were 1.25, 1.38 and 1.20%.

Effects of Dietary Antioxidant Supplementation on the Growth, Serum Chemistry, Body Composition and Challenge Test Results of Juvenile Rockfish Sebastes schlegelii (항산화 기능 사료첨가제가 조피볼락(Sebastes schlegelii)의 성장, 체조성, 혈액성상 및 세균 공격성에 미치는 영향)

  • Yun, Ahyeong;Kim, Hee Sung;Seo, Youngwan;Cho, Sung Hwoan;Bae, Jun Young
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.49 no.3
    • /
    • pp.323-329
    • /
    • 2016
  • The effects of dietary antioxidant [saltwort (SW), leek (LK), and dandelion (DD)] supplementation on the growth, body composition, serum chemistry, and challenge test results of juvenile rockfish, Sebastes schlegelii, were determined. In an experiment, 320 fish were randomly distributed into eight, 50-L flow-through tanks (40 fish per tank). Four experimental diets were prepared: the control diet (Con) with synthetic antioxidant: and diets with SW, LK, or DD from natural sources. Each diet was randomly assigned to duplicate tanks of fish, which were hand-fed to satiation twice daily for 8 weeks. After the 8-week feeding trial, 20 fish from each tank were artificially infected with Streptococcus iniae and monitored for 6 days. The dietary additives did not affect survival, weight gain, specific growth rate, feed efficiency (FE), protein efficiency ratio (PER), or plasma chemistry. However, the cumulative mortality of fish fed the SW, LK and DD diets was lower than that of fish fed the control diet beginning 4 days after infection. In conclusion, dietary supplementation with SW, LK, and DD did not affect the growth, FE, PER, or plasma chemistry of rockfish. However, dietary inclusion of SW, LK, and DD lowered the mortality of rockfish following infection with S. iniae.

Interactions between common heterotrophic protists and the dinoflagellate Tripos furca: implication on the long duration of its red tides in the South Sea of Korea in 2020

  • Eom, Se Hee;Jeong, Hae Jin;Ok, Jin Hee;Park, Sang Ah;Kang, Hee Chang;You, Ji Hyun;Lee, Sung Yeon;Yoo, Yeong Du;Lim, An Suk;Lee, Moo Joon
    • ALGAE
    • /
    • v.36 no.1
    • /
    • pp.25-36
    • /
    • 2021
  • The mixotrophic dinoflagellate Tripos furca causes red tides in the waters of many countries. To understand its population dynamics, mortality due to predation as well as growth rate should be assessed. Prior to the present study, the heterotrophic dinoflagellates Noctiluca scintillans, Polykrikos kofoidii, Protoperidinium steinii, and mixotrophic dinoflagellate Fragilidium subglobosum were known to ingest T. furca. However, if other common heterotrophic protists are able to feed on T. furca has not been tested. We explored interactions between T. furca and nine heterotrophic dinoflagellates and one naked ciliate. Furthermore, we investigated the abundance of T. furca and common heterotrophic protists in coastal-offshore waters off Yeosu, southern Korea, on Jul 31, 2020, during its red tide. Among the tested heterotrophic protists, the heterotrophic dinoflagellates Aduncodinium glandula, Luciella masanensis, and Pfiesteria piscicida were able to feed on T. furca. However, the heterotrophic dinoflagellates Gyrodiniellum shiwhaense, Gyrodinium dominans, Gyrodinium jinhaense, Gyrodinium moestrupii, Oblea rotunda, Oxyrrhis marina, and the naked ciliate Rimostrombidium sp. were unable to feed on it. However, T. furca did not support the growth of A. glandula, L. masanensis, or P. piscicida. Red tides dominated by T. furca prevailed in the South Sea of Korea from Jun 30 to Sep 5, 2020. The maximum abundance of heterotrophic dinoflagellates in the waters off Yeosu on Jul 31, 2020, was as low as 5.0 cells mL-1, and A. glandula, L. masanensis, and P. piscicida were not detected. Furthermore, the abundances of the known predators F. subglobosum, N. scintillans, P. kofoidii, and Protoperidinium spp. were very low or negligible. Therefore, no or low abundance of effective predators might be partially responsible for the long duration of the T. furca red tides in the South Sea of Korea in 2020.

Effect of Salinity on Survival and Growth of 3 Gobiidae (염분변화가 망둑어과 어류 3종의 생존 및 성장에 미치는 영향)

  • Hwang, Un-Gi;Min, Eun-Yong;Kang, Ju-Chan
    • Korean Journal of Environmental Biology
    • /
    • v.30 no.1
    • /
    • pp.9-14
    • /
    • 2012
  • The gobiidae, $Tridentiger$ $trigonocephalus$, $Chasmichtthys$ $dolichognathus$ and $Favonigobius$ $gymnauchen$ were reared for 4 weeks under 0~33.6‰ salinity conditions to examine the effects of various salinity on its survival and growth. Survival rate of $C.$ $dolichognathus$ and $F.$ $gymnauchen$ were significantly declined below 3.4‰ and 0‰, respectively. Growth rate of $T.$ $trigonocephalus$ was significantly reduced 0‰ salinity. Growth rate of $C.$ $dolichognathus$ and $F.$ $gymnauchen$ exposed to ${\geq}$13.4‰ and ${\geq}$6.7‰ were significantly higher than those of gobiidae exposed to below ${\leq}$10.1‰ and ${\leq}$3.4‰ salinity, respectively. This study reveled that low salinity (${\leq}$3.4‰) reduced survival and growth rates of the 3 gobiidae suggesting potential influence on the natural mortality of gobiidae in the coastal areas.

Effects of Salinity on Survival, Growth and Oxygen Consumption Rates in the Mysid, Neomysis awatschensis (곤쟁이, Neomysis awatschensis의 생존, 성장 및 산소 소비율에 미치는 염분의 영향)

  • 지정훈;황운기;강주찬
    • Korean Journal of Environmental Biology
    • /
    • v.21 no.1
    • /
    • pp.66-71
    • /
    • 2003
  • Effects of salinity on survival, growth and oxygen consumption rates were examined in the mysid, Neomysis awatschensis. Mysids were exposed to various concentrations of salinity (0, 3.4, 6.7, 10.1, 13.4, 20.2, 27.4 and 33.6$\textperthousand$) for 40 days. Survival rate was significantly declined at below 6.7$\textperthousand$ after 40 days. Body length and daily growth rate of mysids exposed at below 6.7$\textperthousand$ salinity were significantly decreased than those of mysids exposed at above 10.1$\textperthousand$ salinity. Oxygen consumpiton rate of mysid exposed at salinity raining of 10.1~39.6$\textperthousand$ during 40 days not greatly changed in comparison with that before salinity treatment, but that of mysid exposed at below 6.7$\textperthousand$ significantly decreased. These results indicated that low salinity concentration ($\leq$6.7$\textperthousand$) reduced survival, growth and oxygen consumption rates of the mysid suggesting potential influence on the natural mortality of Neomysis awatschensis in the estuarine and coastal areas.

Growth Performances of Artificial Hybrids on Some Deciduous Quercus Taxa (I) (낙엽성(落葉性) 참나무류의 인공교잡(人工交雜) 묘목(苗木)의 생육(生育) 특성(特性) (I))

  • Lee, Jeong Ho;Kwon, Ki Won
    • Journal of Korean Society of Forest Science
    • /
    • v.88 no.4
    • /
    • pp.485-489
    • /
    • 1999
  • The germination percentages of Quercus hybrid seeds produced in 1994 using stored pollens were low. The survival rate and height growth within 2 years differed according to crossing combinations. The survival rate and growth of seedlings from hybrid seeds produced in 1991 and 1993 were investigated. The survival rates of five-year-old and three-year-old seedlings were from 71 to 100% and from 33 to 100%, respectively. The survival rates differed according to cross combinations. The mortality of seedlings increased in proportion to the increase of percentages of dwarf seedlings. The growth of five-year-old seedlings, of which mother tree was Q. aliena, was the best. The growth of seedlings produced by artificial crossing tended to be worse than that of natural crossing.

  • PDF

A Comparative Study of Serologic Methods for Detection of Mumps Antibody in Korean Children (한국 소아의 Mumps 바이러스 항체보유에 관한 혈청학적 진단방법의 비교)

  • Park, Hae-Kyung
    • The Journal of the Korean Society for Microbiology
    • /
    • v.21 no.4
    • /
    • pp.473-480
    • /
    • 1986
  • Mumps is an extremly common infectious disease affecting predominantly young children hut it is not a severe disease in terms of mortality. One hundred and two sera from infants of 3 different groups which are vaccinated, unvaccinated and unknown were detected to mumps antibody. The tests used were Complement Fixation(CF) test, Single Radial Hemolysis(SRH) test, Hemagglutination Inhibition(HI) test, Enzyme Linked Immunosorbent Immunoglobulin G(ELISA IgG) test, Enzyme Linked Immunosorbent Immunoglobulin M(ELISA IgM) test. 1. The rate of positivity for mumps antibody in 102 sera wera 89.16%(74/83) by Hl test, 68.83%(53/77) by ELISA IgG test, 64.58%(62/96) by SRH test, 63.24%(43/68) by ELISA IgM test and 50.00%(49/98) by CF test. 2. The rate of positivity by 5 tests for 55 sera turned out to be very similar with above results respectively. 3. The correlation coefficients(r) between ELISA IgG test ant H1 test, ELISA IgG test and ELISA IgM test were 0.34(P<0.0l) and 0.31(P<0.02), respectively. 4. The percentage of apparently natural infection of mumps seemed to be 65.15%(43/66) in infants. 5. Seroconversion rate of mumps by vaccination were 90.91%(10/11). 6. Among the 53 infants who were tested with ELISA IgG 15 were below 15 months age of(28.30%) and this percentage may be taken as a suggestion that mumps vaccination should be given earlier than present practice. 7. ELISA IgG test was found very sensitive and recommendable method for large scale screening for the presence of antibody to mumps.

  • PDF

Establishment and evaluation of the VX2 orthotopic lung cancer rabbit model: a ultra-minimal invasive percutaneous puncture inoculation method

  • Wang, Lijuan;Che, Keke;Liu, Zhonghong;Huang, Xianlong;Xiang, Shifeng;Zhu, Fei;Yu, Yu
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.22 no.3
    • /
    • pp.291-300
    • /
    • 2018
  • The purpose of the present work is to establish an ultra-minimal invasive percutaneous puncture inoculation method for a VX2 orthotopic lung cancer rabbit model with fewer technical difficulties, lower mortality of rabbits, a higher success rate and a shorter operation time, to evaluate the growth, metastasis and apoptosis of tumor by CT scans, necropsy, histological examination, flow cytometry and immunohistochemistry. The average inoculation time was 10-15 min per rabbit. The tumorbearing rate was 100%. More than 90% of the tumor-bearing rabbits showed local solitary tumor with 2-10 mm diameters after two weeks post-inoculation, and the rate of chest seeding was only 8.3% (2/24). The tumors diameters increased to 4-16 mm, and irregularly short thorns were observed 3 weeks after inoculation. Five weeks post-inoculation, the liquefaction necrosis and a cavity developed, and the size of tumor grew further. Before natural death, the CT images showed that the tumors spread to the chest. The flow cytometry and immunohistochemistry indicated that there was less apoptosis in VX2 orthotopic lung cancer rabbit model compared to chemotherapy drug treatment group. Minimal invasive percutaneous puncture inoculation is an easy, fast and accurate method to establish the VX2 orthotopic lung cancer rabbit model, an ideal in situ tumor model similar to human malignant tumor growth.

Hybrid Endovascular Operation for Aorto-Iliac Artery Aneurysm - A case report - (대-장골동맥류의 하이브리드(Hybrid) 치료 - 1예 보고 -)

  • Lee, Jae Wook;Won, Yong-Soon;Shin, Hwa-Kyun;Her, Keun;Kim, Dong-Hyun
    • Journal of Chest Surgery
    • /
    • v.42 no.1
    • /
    • pp.111-114
    • /
    • 2009
  • Aorto-iliac artery aneurysms are very rare and the natural course of this disease is not well known. However, the risk of rupture is high and the mortality rate after rupture is extremely high. Preserving the pelvic circulation is important for the treatment of aorto-iliac artery aneurysms. We report here on a case of a patient suffering with aorto-iliac artery aneurysms, and these were treated by a hybrid endovascular operation that combined an open bypass of both iliac vessels with endovascular repair.

Induction of Mitochondrial-Mediated Apoptosis by Morinda Citrifolia (Noni) in Human Cervical Cancer Cells

  • Gupta, Rakesh Kumar;Banerjee, Ayan;Pathak, Suajta;Sharma, Chandresh;Singh, Neeta
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.1
    • /
    • pp.237-242
    • /
    • 2013
  • Cervical cancer is the second most common cause of cancer in women and has a high mortality rate. Cisplatin, an antitumor agent, is generally used for its treatment. However, the administration of cisplatin is associated with side effects and intrinsic resistance. Morinda citrifolia (Noni), a natural plant product, has been shown to have anti-cancer properties. In this study, we used Noni, cisplatin, and the two in combination to study their cytotoxic and apoptosis-inducing effects in cervical cancer HeLa and SiHa cell lines. We demonstrate here, that Noni/Cisplatin by themselves and their combination were able to induce apoptosis in both these cell lines. Cisplatin showed slightly higher cell killing as compared to Noni and their combination showed additive effects. The observed apoptosis appeared to be mediated particularly through the up-regulation of p53 and pro-apoptotic Bax proteins, as well as down-regulation of the anti-apoptotic Bcl-2, Bcl-$X_L$ proteins and survivin. Augmentation in the activity of caspase-9 and -3 was also observed, suggesting the involvement of the intrinsic mitochondrial pathway of apoptosis for both Noni and Cisplatin in HeLa and SiHa cell lines.