Death‐feigning behaviours increase survival rate of littoral cladocerans under predation by odonate larvae

2021 ◽  
Author(s):  
Sayumi Yamada ◽  
Jotaro Urabe



2014 ◽  
Vol 2 (3) ◽  
Author(s):  
Ayu Maleko ◽  
Hengky J Sinjal ◽  
Henky Manoppo

The objective of this research was to evaluate the effect of feed supplemented with baker’s yeast on survival rate of nile tilapia larvae and to determine the effective dose of baker’s yeast that could optimally improve larval quality.  The research was conducted at Pathology and Clinic of Fish Disease from June – September 2014.  Fish as brood stock candidates was cultivated at five concrete tanks (2x1x1 m3) at a density of 30 fish per tank.  Each tank was equipped with water inlet, outlet and water pump for recirculating and aerating.  After seven days of adaptation, fish was fed pellet supplemented with baker’s yeast at five different doses (0, 10, 20, 30, 40 g/kg food) for four consecutive weeks at 4%/bb/day, twice daily.  Larva was captured with seser and moved into five glass aquaria with density of 20 larvae/aquarium and reared for two weeks.  Data collected was survival rate of larvae achieved until the end of larval rearing.  Research result showed that larvae produced by brood stock fed food supplemented with 10 g baker’s yeast per kg food had the highest survival rate namely 60%.  As conclusion, supplementation of baker’s yeast into brood stock feed might increase survival rate of larvae.   Keywords:  nile tilapia, baker’s yeast, larvae, survival rate



2015 ◽  
Vol 1622 ◽  
pp. 368-376 ◽  
Author(s):  
Nereida Valero ◽  
Jesús Mosquera ◽  
Sirley Alcocer ◽  
Ernesto Bonilla ◽  
Jenny Salazar ◽  
...  


1974 ◽  
Vol 83 (4) ◽  
pp. 481-486 ◽  
Author(s):  
Max L. Som

Of 84 surgically treated cases of postcricoid carcinoma, 23 had a pharynxesophageal reconstruction by use of a laryngotracheal autograft. This procedure is most suitable in females with manifestations of the Paterson-Broun-Kelly syndrome. The distal esophagus is not “at risk” because of skip areas or second primary lesions. Failures are due predominantly to inability to control the lymphatic metastasis. Stomal recurrence may be due to ascending metastasis from the tracheoesophageal groove and mediastinum. A routine combined neck dissection is urged in all instances. Mediastinal node extirpation with or without resection of the manubrium may increase survival rate. Adequate surgical exposure with visualization, palpation, and exploration of the extent of the cancer is suggested prior to determination of the method of reconsruction of the pharyngoesophagus. In selected cases without previous radiotherapy the laryngotracheal autograft has proved satisfactory.



Tumor Biology ◽  
2013 ◽  
Vol 34 (3) ◽  
pp. 1595-1603 ◽  
Author(s):  
Sang-Woon Lee ◽  
Seong-Gon Kim ◽  
Young-Wook Park ◽  
HaeYong Kweon ◽  
Jwa-Young Kim ◽  
...  


2021 ◽  
Vol 25 (1) ◽  
pp. 45-52
Author(s):  
A.I. Smirnov ◽  
◽  
F.S. Orlov ◽  
P.A. Aksenov ◽  
V.F. Nikitin ◽  
...  

This paper presents the results of a study that was conducted in the Sergiev Posad forestry of the Moscow region forestry Department with the participation of the laboratory of the Department of Forest crops, breeding and dendrology of the BMSTU (Mytishchi branch). This study shows the technology of planting European (Picea abies L.), seedlings in culture, which can significantly increase the survival rate of experimental samples and improve their biometric characteristics: height, diameter of the root neck, weight, and also the anatomical structure of seedlings. The experiments were performed using a low-frequency generator «Rost-Active», the author’s technology pre-sowing treatment of seeds and seedlings by an electromagnetic field, hydrogel (polymer water-retaining agent) and a method of histometric analysis of cross sections of control and experimental stems of European spruce seedlings. The results of the study indicate a clear positive effect of electromagnetic field and hydrogel on the increase in survival of experimental samples of seedlings of common European spruce in relation to the control. Also, the results of comparative histometric analysis indicate the effectiveness of methods for treating pine seedlings with low-frequency EMF and applying hydrogel to the soil.



2020 ◽  
Vol 8 (1) ◽  
pp. 89
Author(s):  
Pitjont Tomatala ◽  
Petrus Paulus Letsoin ◽  
Evangelin Martha Yulia Kadmaer

Sea cucumbers are an Indonesian fisheries export commodity. Sea cucumber populations that are endangered in nature encourage sea cucumbers to be produced through hatchery and nursery. Through nursery, it is expected that sea cucumber juveniles are stronger and can increase survival rate when stocked in growth containers or restocked. This study aims to provide better sandfish nursery techniques and local area characteristics to support hatchery activities. This study was conducted in May - July 2018 at the Hatchery CV Pesona Manir Rat, Southeast Maluku Regency. Juvenile sandfish 30-36 days old, rearing in hapa measuring 100 x 100 x 70 cm with a density of 200 individuals/hapa. In one tank rearing is placed one hapa. During rearing, 100-150% of water is changed and given one-liter Navicular sp. every day. Aeration was installed 4 points on each hapa and water quality measurement was conducted every day. At the end of the study, body length measurements and mortality calculations were conducted. The result is that sea cucumber juvenile which is maintained has absolute growth ranging from 1.98 to 2.1 cm with an average absolute growth of 2.03 cm. The average mortality obtained was 53.83% with a range of 53% - 55%. Based on the discussion it was concluded that this technique can be applied in sandfish nursery. ABSTRAKTeripang merupakan komuditi eksport perikanan Indonesia. Populasi teripang yang terancam di alam mendorong teripang harus diproduksi melalui pembenihan dan pendederan. Melalui pendederan diharapakan anakan teripang lebih kuat dan dapat bertahan hidup lebih baik ketika ditebar pada wadah pembesaran atau direstoking. Penelitian ini bertujuan memberikan informasi teknik pendederan teripang pasir yang lebih baik dan berkarakteristik daerah setempat guna menopang kegiatan pembenihan. Penelitian ini dilaksanakan pada bulan Mei – Juli 2018 di Hatchery CV Pesona Manir Rat, Kabupaten Maluku Tenggara. Juvenil teripang pasir berusia 30 – 36 hari, dipelihara pada hapa berukuran 100 x 100 x 70 cm dengan kepadatan 200 individu / hapa. Pada satu bak pemeliharaan ditempatkan satu buah hapa. Selama pemeliharaan dilakukan pergantian air sebanyak 100 – 150 % dan diberikan satu liter Navicular sp. setiap hari. Aerasi dipasang sebanyak 4 titik pada setiap hapa dan dilakukan pengukuran kualitas air setiap hari. Diakhir penelitian, dilakukan pengukuran panjang tubuh dan perhitungan mortalitas. Hasilnya juvenile teripang yang dipelihara mengalami pertumbuhan mutlak berkisar antara 1,98 – 2,1 cm dengan rata-rata pertumbuhan mutlak sebesar 2,03 cm. Mortalitas rata-rata yang diperoleh sebesar 53, 83 % dengan kisaran 53 % - 55 %. Berdasarkan pembahasan disimpulkan bahwa teknik ini dapat diterapkan dalam pendederan teripang pasir. 



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