Cm In Body Length Research Articles

Effects of photoperiods on growth and quality of white leg shrimp (Litopenaeus van-namei) in biofloc system

This study aims to determine suitable photoperiod for growth of white leg shrimp in supper-intensive tank culture system applying biofloc technology. The experiment was randomly designed indoor with different photoperiod treatments, including (i) 24 hours Dark; (ii) 6 hours Light: 18 hours Dark; (iii) 12 hours Light: 12 hours Dark; (iv) 18 hours Light: 6 hours Dark and (v) 24 hours Light. The lighting treatments, it was set with a 55w compact fluorescent (light intensity ~ 6000 lux). Shrimp with initial weight at 0.84g and 4.45cm of body length were cultured at density of 150 inds/m3 in Biofloc system (C:N=15:1), with 300L of water volume, 15‰ of salinity. Results showed that after 90 days of culture, water quality were in suitable range for shrimp growth. Body weight (BW) of shrimp among treatments were from 18.28 to 22.96 g. In which, BW of shrimp in completely dark condition was the lowest and significantly different compared to the others (p3), not significantly different compared to 18 hours Light (2,23kg/m3 ) but significantly different compared to the others. Besides, shrimp in the treatments with Light showed stronger color compared to shrimp in completetly dark condition.

Study of the dairy characters of lactating Murrah buffaloes on the basis of body parts measurements.

Aim:The aim of the study was to correlate the milk yield of Murrah buffaloes with certain body parts measurements.Materials and Methods:A total of 70 lactating Murrah buffaloes were selected from Buffalo Farm, Lala Lajpat Rai University of Veterinary and Animal Science, Hisar and were randomly selected in a range from first to fifth parity. Traits studied were 305 days milk yield (MY), body weight (BW), body length (BL), muzzle width (MW), height at wither (HW), abdominal girth (AG), chest girth (CG), body depth fore, body depth rear, hip bone distance (HBD), pin bone distance (PBD), skin thickness (STK), and tail length (TL). Data were collected and statically analyzed by Pearson’s correlation method.Result:The result of this study showed that Murrah buffaloes had the average 2604.8±39.5 kg for MY, 556.1±4.9 kg for BW, and 152.2±0.8 cm for BL. This study showed that buffaloes had positive significant (p<0.05) correlation between MY and BW (0.26). Highly significant (p<0.01) correlation was observed between MY and AG (0.64), MW (0.42). Significant (p<0.01) negative correlation was observed between MY and STK (−0.79). Different body part measurements (BW, BL, HW, AG, CG, MW, TL, BD, PBD, HBD, STK) were significantly correlated with each other.Conclusion:This study can be helpful as a selection tool to enhance and evaluate the production potential by setting standards of Murrah buffalo breed. BW, abdominal growth, muzzle thickness, and STK were found key factors while selecting a dairy Murrah buffalo.

KARAKTERISTIK MORFOLOGI ESOFAGUS DAN LAMBUNG BANDIKUT (Echymipera kalubu) (Esophagus and Stomach Morphological Characteristic of Bandicoot Echymipera kalubu (Marsupialia: Peroryctidae))

The morphological characteristics of the stomach and esophagus of five adults bandicoot (Echymipera kalubu) with average 1.16±0.29 kg in body weight and 38.2±4.76 cm in body length were studied macroscopically, microscopically and histochemically. The bandicoot esophagus were found relatively long about one third of body length. The esophageal glands were identified along the esophagus and the number decreased gradually from cranial to caudal region. In addition of smooth muscle, skeletal muscles were also examined in the external muscle layer of esophagus up to the esophageal junction. The stomach of the E. Kalubu had short lesser curvature and three glandular regions of cardiac, fundic and pyloric glands were observed, respectively. The cardiac glands area was small and concentrated in the cranial part of the stomach. The fundic glands area occupied about half parts of the stomach. Mucous surface epithelial cells, mucous neck cells, parietal cells and chief cells were found in the entire fundic gland. The parietal cells were the most abundant cells in the major curvature distributed from the basal to neck area of the glands, but few in the minor curvature. Chief cells were mostly distributed in the basal gland. The pyloric glands region was observed in caudal part of the stomach. Staining with alcian blue-periodic acid Schift (AB-PAS) showed various distribution and intensity of neutral and acid mucopolysaccharides in the esophageal and stomach mucosa. High concentration of neutral and acid mucopolysaccharides were detected in esophageal and stomach glands with various concentration. Morphological characteristics of the esophagus and stomach were assumed to be related to the digestive processes in the gastrointestinal tract of bandicoot.

The Morphology External Organs Of The Body Of Bandicoot Echymipera Kalubu

&lt;p&gt;Study on the morphology of external organs of the body of peroryctids is less available. Bandicoot (&lt;em&gt;Echymipera kalubu&lt;/em&gt;) is one of marsupial in peroryctids and is endemic species in Papua. The morphological characteristic of the external organs of five adults bandicootS (&lt;em&gt;E. kalubu&lt;/em&gt;) with the body weight of 1,16 ± 0,29 kg and 38,2 ± 4,76 cm of body length were studied macroscopically. The external organs of the body of bandicoot were identified the eye, nose, limb and reproductive systems. The nose of the &lt;em&gt;E. kalubu&lt;/em&gt; had tactile hairs on the trunk and the cheek under the eye. The ear of the &lt;em&gt;E. kalubu&lt;/em&gt; had tragus. The forelimb which were shorter of the hind limb. The hind limb unique where only consisting of four toes and having five claws. The tail of the &lt;em&gt;E. kalubu&lt;/em&gt; there was long but there were also species are not having tail. Uniqueness was also in the external organs of reproductive systems which there is only scortum, that out the abdomen of the body. The penis not found around skortum. The condition reproductive system of male &lt;em&gt;E. kalubu&lt;/em&gt; like cloaca in poultry. The penis only will look when there was coitus. In a female has sac with the nipple.&lt;/p&gt;

Effect of the photoperiod on the larval development, body growth and muscle cellularity of shi drum ( Umbrina cirrosa L.)

Shi drum (Umbrina cirrosa L.) larvae were maintained under three photoperiod regimes: a natural photoperiod regime (16L:8D), continuous light (24L) and equal durations of light and dark (12L:12D) from the end of the vitelline phase to the end of the metamorphosis. Muscle and body parameters were studied at hatching and at 4, 10, 14, 39 and 55 days post hatching (dph). During the vitelline phase, the total body length growth was scarce, whereas the muscle grew significantly, being the hypertrophy of the main mechanism involved. Both the total body length and the hypertrophy were significantly greater at 16L:8D than in the rest of photoperiod regimes. At 10 and 14 dph, the greatest body length was reached at 16L:8D, followed by the 24L group, showing the 12L:12D group the lowest values. At 14 dph, the hypertrophy and hyperplasia were also higher at 16L:8D than in the rest of groups. At 39 dph, the highest values of body length were reached in both 16L:8D and 12L:12D regimes, this latter group reaching the highest values of hypertrophy, thus showing a compensatory growth when comparing with the previous stages. The end of the metamorphosis took place at 50–55 dph in all the groups, with 2.7–3.1 cm of body length (P > 0.05). At this stage, the transverse area of the white muscle was similar among the groups, but the greatest hypertrophy was reached at 16L:8D, whereas the highest hyperplasia was reached at 24L.

Differential proteomic expression of human placenta and fetal development following e-waste lead and cadmium exposure in utero

Prenatal exposure to lead (Pb) and cadmium (Cd) has been associated with a series of physiological problems resulting in fetal growth restriction. We aimed to investigate the effects of Pb and Cd exposure on placental function and the potential mechanisms involved in fetal development. Placental specimens and questionnaires were collected from an e-waste area and a reference area in China. Two-dimensional electrophoresis combined with MALDI-TOF-MS/MS and molecular network relationship were performed to analyze differentially expressed proteins using a compositing sample pool. Compared with the reference group, the exposed group exhibited significantly higher levels of placental Pb and Cd (p<0.01), shorter body length and higher gestational age (p<0.01). After bivariate adjustment in a linear regression model, decreases of 205.05g in weight and 0.44cm in body length were associated with a 10ng/g wt increase in placental Cd. Pb showed a negative trend but lacked statistical significance. Proteomic analysis showed 32 differentially-expressed proteins and were predominantly involved in protein translocation, cytoskeletal structure, and energy metabolism. Fumarate hydratase was down-regulated in the exposed placenta tissues and validated by ELISA. Alterations in placental proteome suggest that imbalances in placental mitochondria respiration might be a vital pathway targeting fetal growth restriction induced by exposure to Cd.

Growth performance of pearl goldfish juvenile carassius auratus cultured in 3 ppt salinity with different exposure time of electric field

&lt;p&gt;ABSTRACT&lt;/p&gt;&lt;p&gt;&lt;br /&gt;Growth rate of pearl goldfish juvenile Carassius auratus relatively slow to reach market size which will take approximately three months. To accelerate its growth can be done by providing exposure of the fish to low-power electric fields (10 V) via 3 ppt salinity water, with the goal of providing the close isoosmotic conditions, and also to streamline the flow of electricity from the electrodes to the body of the fish. This study aims to calculate the survival and growth rate of pearl goldfish juvenile of S sizes (2‒4 cm of body length) which were maintained at 3 ppt salinity water and treated by different exposure time of electric field (zero, two, four, and six minutes before feeding) with 10 volt electric power. Fish were cultured at a density of 2 fish/L in the (20×30×20 cm3) aquaria in volume of 6 L of water. Test fish had an average body length of 4.11±0.05 cm and the average body weight of 2.89±0.05 g. Exposure time of electric field were zero, two, four, and six minutes before the fish are fed, performed every day as much as three times i.e. morning, afternoon, and evening. The research design used was completely randomized design with four treatments, namely 0, 2, 4, and 6 (time for exposure is zero/control, two, four, and six minute) with three replications. The results show test fishes exposed to 10 volt electrical field for zero, two, four, and six minutes, have no significant effect on survival rate (P&amp;gt;0.05). For growth performance, four minute exposure treatment gives the best results compared to controls (P&amp;lt;0.05), supported by an increase in the percentage of the ratio of gut length to body length of the fish and higher feed efficiency.&lt;br /&gt;Keywords: long exposure to the electric field, growth performance, pearl goldfish&lt;/p&gt;&lt;p&gt;&lt;br /&gt;ABSTRAK&lt;/p&gt;&lt;p&gt;&lt;br /&gt;Pertumbuhan benih ikan hias maskoki mutiara Carassius auratus relatif lambat, karena untuk mencapai ukuran jual memerlukan waktu sekitar tiga bulan. Untuk mempercepat pertumbuhannya dapat dilakukan dengan pemberian paparan medan listrik berdaya rendah (10 V) ke air media budidaya yang dinaikkan salinitasnya menjadi 3 ppt, dengan tujuan memberikan kondisi mendekati isoosmotik, dan juga untuk mengefektifkan arus listrik dari elektroda ke tubuh ikan. Penelitian ini bertujuan untuk menghitung tingkat kelangsungan hidup dan pertumbuhan benih ikan maskoki mutiara ukuran S (2‒4 cm) yang dipelihara pada media bersalinitas 3 ppt yang diberi perlakuan lama waktu pemaparan medan listrik (nol, dua, empat, dan enam menit sebelum ikan diberi pakan) dengan daya 10 volt. Ikan dipelihara dengan kepadatan 2 ekor/L dalam akuarium berukuran 20×30×20 cm3 dengan volume air 6 L. Ikan uji yang digunakan memiliki panjang rata-rata 4,11±0,05 cm dan bobot rata-rata 2,89±0,05 g/ekor. Pemberian paparan medan listrik dilakukan selama nol, dua, empat, dan enam menit sebelum ikan diberi pakan, dilakukan setiap hari sebanyak tiga kali yaitu pagi, siang, dan sore hari. Rancangan penelitian terdiri atas empat perlakuan, yaitu 0, 2, 4, dan 6 (lama paparan nol/kontrol, dua, empat, dan enam menit) yang diulang masing-masing tiga kali ulangan. Hasil pemaparan arus listrik 10 volt selama nol, dua, empat, dan enam menit, tidak memberikan pengaruh yang nyata pada kelangsungan hidup (p&amp;gt;0,05). Untuk kinerja pertumbuhan, perlakuan paparan empat menit memberikan hasil yang terbaik dibandingkan kontrol (p&amp;lt;0,05), didukung oleh peningkatan persentase nilai rasio panjang usus terhadap panjang tubuh ikan serta nilai efisiensi pakan yang lebih tinggi.&lt;/p&gt;&lt;p&gt;&lt;br /&gt;Kata kunci: lama paparan medan listrik, kinerja pertumbuhan, ikan maskoki mutiara&lt;/p&gt;

Morphometric characterization of local goats of Karnataka

A total of 991 local goats of different age groups were randomly selected for collecting data on morphometric characters from four agro-climatic zones of Southern Karnataka. The overall average body weights of adult males and females were 21.87±0.54 and 21.19±0.44 kg, respectively and the respective values were 59.37±0.82 and 60.38±0.65 cm for height, 59.93±0.83 and 61.58±0.62 cm for chest girth, 60.03±0.81 and 61.29±0.62 cm for paunch girth and 51.47±0.70 and 53.00±0.54 cm for body length. Pearson correlation analysis of various measures revealed significant (P<0.001) correlation between body weights and other measures. Highest correlation was observed between paunch girth and chest girth (0.944) followed by height and chest girth (0.936).

Filming and snorkelling as visual techniques to survey fauna in difficult to access tropical rainforest streams

Dense tropical rainforest, waterfalls and shallow riffle-run-pool sequences pose challenges for researcher access to remote reaches of streams for surveying aquatic fauna, particularly when using capture-based collecting techniques (e.g. trapping, backpack and boat electrofishing). We compared the detection of aquatic species (vertebrates and invertebrates &gt;1cm in body length) within pool habitats of a rainforest stream obtained by two visual techniques during both the wet and dry season: active visual survey by snorkelling and baited remote underwater video stations (BRUVSs). Snorkelling detected more species than a single BRUVS at each site, both within and among seasons. Snorkelling was most effective for recording the presence and abundance of diurnally active small-bodied species (adult size &lt;150mm total length), although both techniques were comparable in detecting large-bodied taxa (turtles, fish and eels). On the current evidence, snorkelling provides the most sensitive and rapid visual technique for detecting rainforest stream fauna. However, in stream sections dangerous to human observers (e.g. inhabited by crocodiles, entanglement, extreme flows), we recommend a stratified deployment of multiple BRUVSs across a range of stream microhabitats within each site.

Analysis of the body structure of Djallonke sheep using a multideterminant approach

This study aimed at using a multivariate approach to describe the body structure of Djallonke sheep in northern Ghana and to determine which approach explains better the variation in body composition. Live weight (LW) and linear body measurements including heart girth (HG), neck girth (NG), chest depth (CD), height at withers (HW), rump height (RH), body length (BL) and pin-bone width (PBW) were obtained from 172 sheep aged between two and three years. The fixed effects of sex and age were tested using the general linear model (GLM) while the Nearest Neighbor method of Hierarchical Cluster Analysis was used to group body traits into clusters. Principal Component Factor Analysis was used to describe the variation in body traits where extracted factors were varimax rotated to enhance interpretability. The analysis of variance revealed significant (P 0.05). Age had no significant influence (P > 0.05) on the body traits. The sheep weighed 26.92 ± 0.89 kg averagely and had averages of other body measurements to be: 71.74 ± 1.23, 40.52 ± 0.79, 27.73 ± 0.52, 60.72 ± 0.86, 59.61 ± 0.87, 58.87 ± 1.06 and 12.81 ± 0.23 cm for HG, NG, CD, HW, RH, BL and PBW, respectively. The product moments of correlation were positive and significant (P < 0.05, 0.01; r = 0.18–0.99) for all pairs of traits. The body traits were categorized mainly into two clusters with the first cluster comprising the HG, HW, RH and BL while NG, CD and PBW formed the second cluster. The grouping of the traits was slightly different in Factor analysis where two underlying principal components (PC) were extracted to discern the variance structure of the Djallonke sheep. The first principal component which consisted of CD, HW, RH, BL and PBW explained 61.26 percent and the second, 12.92 percent thereby giving a maximum of 74.17 percent generalized variance in body measurements. The traits loaded on the first principal component are closely associated with bone growth hence describing the general body size conformation while the traits (HG and NG) on the second component seem to describe only the thoracic region. It can be concluded that both the Hierarchical Cluster analysis and the Factor analysis grouped body traits similarly but the later is to be recommended because of the additional ability of indicating the amount of variation explained by the developed factors.

Non-Consumptive Predator Effects Shape Honey Bee Foraging and Recruitment Dancing

Predators can reduce bee pollination and plant fitness through successful predation and non-consumptive effects. In honey bees, evidence of predation or a direct attack can decrease recruitment dancing and thereby magnify the effects of individual predation attempts at a colony level. However, actual predation attempts and successes are relatively rare. It was not known if a far more common event, just detection of a predator, could inhibit recruitment. We began by testing honey bees' avoidance of the praying mantis (Tenodera sinensis). Larger predators (later mantis instars, ≥4.5 cm in body length) elicited significantly more avoidance (1.3 fold) than smaller mantis instars. Larger instars also attempted to capture honey bees significantly more often than did smaller instars. Foragers could detect and avoid mantises based upon mantis odor (74% of bees avoided an odor extract) or visual appearance (67% avoided a mantis model). Finally, foragers decreased recruitment dancing by 1.8 fold for a food source with a live adult mantis, even when they were not attacked. This reduction in recruitment dancing, elicited by predator presence alone, expands our understanding of predator non-consumptive effects and of cascading ecosystem effects for plants served by an important generalist pollinator.

Semen collection and seminal characteristics of the Australian saltwater crocodile (Crocodylus porosus)

The development of a reliable non-invasive method of crocodile semen collection is fundamental for assessing male fertility and for implementing the benefits of artificial insemination for reproductive and genetic management of farmed populations and the captive breeding of endangered species. Following an initial description of male reproductive anatomy in the saltwater crocodile (Crocodylus porosus), this study developed a successful, reliable method of semen collection using cloacal digital manipulation of the terminal segment of the ductus deferens. Semen was recovered from 30 of 31 collection attempts from a total of 24 sedated males ranging from 197cm to 400cm in body length. Seminal characteristics (including abnormal sperm morphology) and bacteriology were documented for the first time. Mean (±SEM) seminal volume, pH, osmolality, sperm concentration, percentage of motile sperm and the percentage of sperm with an intact membrane measured 0.91±0.16mL, 7.3±0.1, 335.5±9.0mOsmkg-1, 2.29±0.26×109, 50.7±4.2%, and 79.9±3.6%, respectively. Sperm abnormalities included macro and microcephalic nuclei, teratoid spermatozoa, loose heads and a range of abnormal flagella. Most semen samples contained spermatozoa with what are presumed to be cytoplasmic droplets but the confirmation and then significance of this phenomenon as a sperm maturational pathology require further validation. In an attempt to develop targeted antibiotics for use in semen diluents, microflora of the penile shaft, sulcus and semen of a subset of crocodiles was analysed for culture and sensitivity. While a diverse range of bacteria were identified, the majority were sensitive to gentamicin. This study represents the first step towards assessment of breeding soundness examination and the use of artificial insemination technology in the saltwater crocodile industry.

Test of Intercropping &lt;em&gt;Myxocyprinus asiaticus&lt;/em&gt; in the &lt;em&gt;Eriocheir sinensis&lt;/em&gt; Pond

In order to reveal whether the Myxocyprinus asiaticus and the mitten crab Eriocheir sinensis be intercropping well in pond-culture and whether have any influence on specification, production and benefit of the river crab, During March to November, 2011. We chose three mitten crab Eriocheir sinensis ponds of similar hydrology condition and environment in Liu farm, Taizhou city, Jiangshu province to start the test of intercropping Myxocyprinus asiaticus in the mitten crab pond. The control pond mainly cultivates Eriocheir sinensis auxiliary with Macrobrachium nipponense, siver carp and Siniperca chautsi, while the testing ponds intercropping Myxocyprinus asiaticus juveniles additional. Stocking density of the 2 nd pond and the 3 rd pond is, respectively 750 and 900 fish/hm 2 with averaging 10 cm in body length. After 250 days' cultivation, the average weight of each one is 997.8 g with survival rate of 91.2%. The average output of the 2 nd pond is 342 kg/hm 2 and the 3 rd pond is 405.75 kg/hm 2 . Compared with the contrast pond's 35,505 yuan/hm 2 net profit, the 2 nd pond and the 3 rd pond separately has 22,995 and 27,032 yuan/hm 2 more net profit with growth rate at 64.77 and 76.14%. The average specification of the Eriocheir sinensis in these three ponds is 169 g/one. Specification of the Eriocheir sinensis in the intercropping pond has no obvious difference with the one in the control pond.

Ultrasound evaluation of the gonadal structure in sex-reversed rainbow trout females

Ultrasound approach has been used to assess morphology of the gonadal structure in the sex-reversed rainbow trout females (neomales) provided in the course of 11β-hydroxyandrostenedione treatment applied within gonadal differentiation period. Eighteen matured individuals (in range 38.0–48.6 cm of body length and 802–1644 g of body weight) were scanned using digital ultrasound apparatus (DP-6900 model) Mindray Ltd., during the spawning season. After screening, fishes were killed to validate the morphological configuration and position of the gonads in the body cavity. The favorable place for cross-sectional imaging of gonadal lobes was half of the distance between the pectoral and pelvic fins below lateral line of neomales. Most of the examined specimens (61 %) had properly shaped, paired testis. Moreover, presence of individuals with asymmetrical gonads (33 %) and one bisexual fish was confirmed. There were no differences between total volume of sampled semen and sperm motility, but statistically significantly different in sperm concentration within selected (with symmetrical and asymmetrical testis) groups of neomales. It was confirmed that ultrasonic imaging is an efficient and accurate method to determine the state of gonads of mature sex-reversed rainbow trout females during spawning season and offers the opportunity for non-invasive detection of any morphological anomalies in their gonads.

The Morphological Study of Wild and Farmed Olive Flounder (Paralichthys olivaceus): The Role of Indirect Selection within and between Populations.

This study was conducted to analyze the difference of body types within and between wild and farmed populations of olive flounder Paralichthys olivaceus using measured records of morphological traits. The results showed that surveyed traits and standard deviation were 1,355±742 g of body weight, 48.01±7.79 cm of total length, and 40.96±6.80 cm of body length. Also body height, body shape index and condition factor were 17.19±3.43 cm, 9.99±0.74 and 11.16±1.54, respectively. As result of least squares mean and standard error for each trait assumed in this study, those of farmed population showed significantly higher than those of wild population in all traits, exclusively in total length and body length (p<0.01). Particularly, the values of the body height and the body weight of the farmed population were higher than those of the wild population in the same total length. And the phenotypic correlation coefficients of the body weight, the total length, the body length and the body height showed strong positive correlation in all populations. These result suggested that morphological differences exist in farmed and wild flounder. Therefore, introduction of wild flounder is essential for the future production to improve the body type of farmed flounder, and parental fish should be chosen by considering selection of commercially important traits in the production process.

FECUNDIDAD DE «CHIOCHÍO» Psectrogaster rutiloides (PISCES: CURIMATIDAE) EN UCAYALI, PERÚ.

Estudios sobre el potencial de fecundidad del chiochio, Psectrogaster rutiloides , son escasos pese a ser una de las principales especies en la pesca semicomercial y de subsistencia para consumo humano de la cuenca del Ucayali, Peru. Se colectaron 74 hembras en estadio de madurez IV en octubre y noviembre de 2009. Se midio la longitud total, se registro el peso corporal y el peso de las gonadas y se determino el numero de ovocitos por el metodo gravimetrico. La talla y peso corporal fue de 15.2 ± 1.9 cm y 68.5 ± 24.7 g, respectivamente, y el peso de las gonadas fue de 12.5 ± 5.3 g. El numero estimado de ovocitos fue de 45 058 ± 20 770. La fecundidad relativa vario entre 1194 y 6619 ovocitos por cm de talla, entre 302 y 1202 ovocitos por gramo de peso corporal, y entre 2654 y 8739 ovocitos por gramo de gonadas. El analisis de regresion indica que el peso de las gonadas es un buen elemento para estimar la fecundidad en esta especie

Prokaryotic expression,purification and immune efficacy of VP6 protein of grass carp reovirus

In order to study the immuno-protective efficacy of GCRV-VP6 subunit vaccine,the recombinant expression vector pET28a(+)-VP6 was constructed by cloning vp6 gene of GCRV into the prokaryotic expression plasmid pET-28a(+).The results of SDS-PAGE and Western-blotting showed that the molecular mass of the recombinant VP6 protein was approximately 43 ku.The recombinant protein reached 20% of the total bacterial proteins,and was mainly in the form of insoluble bodies.The grass carp(60-120 g in body weight and 14-20 cm in body length)was immunized with 500 μg purified VP6 protein by Ni2+ affinity chromatography and antibody titers in the blood of fish were determined by means of indirect agglutination reaction on the 14th,21st,28th,49th and 70th days post-vaccination.The results showed that the specific antibody could be detected on the 14th day,reached peak on the 21st day and could be still detected on the 70th day after immunization.The fish in vaccinated group and control group were challenged with GCRV on 21st days after vaccine delivery and the relative survival rate in the vaccined group was 100%.These results provided important academic foundation for research and development of GCRV genetic vaccine.

板櫃川における魚類生息場の季節変化の調査

It is important to make clear seasonal changes of fish habitat quality in rivers. There are still many unsolved question in fish habitat quality, because this consists of quite complex system. In this study, field surveys of seasonal changes of fish habitat quality were conducted through nine months in Itabitsugawa river which belongs to class B river. It was found that Carassius langsdorfi moves from pool to riffle through winter to summer. Zacco temminckii and Zacco platypus evade Carassius langsdorfi in all seasons, because the body length of Carassius langsdorfi is larger than that of Zacco temminckii and Zacco platypus. Further, Zacco temminckii evades Zacco platypus which is larger than 8cm of body length.

Ecological risk resulting from invasive species: a lesson from riparian wetland rehabilitation

Riparian wetland rehabilitation (RWR) is increasingly significant for the maintenance of the integrity and health of a river, but it may unexpectedly cause ecological risks. Here, we demonstrate that a pilot RWR project brought about the invasion of an exotic species, Pomacea canaliculata, to the reformed wetland and, furthermore, led to ecological risks in the river. An open wetland (OW) and a half-open wetland (HOW) were regenerated through the destruction of a cement embankment along the riverbank. The amount of emergent, submerged, hygrophytic, and floating plants originally surviving in the upstream region were introduced and replanted in the downstream wetlands. However, we found that the golden apple snail invaded and propagated quickly, reaching a density of 10 snails/m2, dominating the HOW 1 month after the rehabilitation process. Approximately 60% of the vegetation was grazed upon by the snails in the HOW, whereas only 10% of the vegetation was lost in the OW. The most harmful snails were identified as those that were 31-40 cm in body length and 22.43-42.95 g in body weight. Eight sets of laboratory tests demonstrated that the preferred order of vegetable consumption by the snails is Hydrilla verticillata, Ceratophyllum demersum, Potamogeton crispus, and Vallisneria spiralis. Both fresh vegetables and slow flow in the HOW were favorable to the growth and propagation of the snails under suitable temperature and humidity conditions. The river water quality, with a high chemical oxygen demand and concentrations of ammonia, had no influence on the survival of the snails. It appeared that the invasive snail caused an ecological risk to the river, but man-made replanting should be the first driving power of the risk. The best rehabilitation method must still be elucidated.

자연산 점몰개, Squalidus multimaculatus Hosoya et Jeon의 새인두흡충, Clinostomum complanatum (Rudolphi, 1814) 감염

경상북도 영덕군의 하천에 서식하는 점몰개 spotted barbel gudgeon (Squalidus multimaculatus Hosoya et Jeon)의 근육에서 새인두흡충 Clinostomum complanatum (Rudolphi, 1814)의 피낭유충이 발견되었다. 감염된 점몰개는 "yellow grub"인 기생충의 피낭유충으로 인해 표면이 울퉁불퉁하게 보였으며, 수면위에 힘없이 유영하였고 일부 폐사한 개체도 발견되었다. 분리된 탈낭유충의 형태는 혓바닥모양이었으며, 크기는 2.85~5.89 mm<TEX>${\times}$</TEX>0.8~1.99 mm였다. 어체당 1~98개의 피낭유충을 분리하였으며 평균 감염수는 25개로 나타났다. 특히, 성어크기인 평균 7cm 정도의 점몰개는 100% 감염되어 있었다. 본 연구는 한국의 자연수계에 서식하는 어류에서 C. complanatum 의해 질병이 발생하고 폐사가 일어난 첫 보고이다. The metacercariae of Clinostomum complanatum (Rudolphi, 1814) were isolated in the whole body muscle of wild freshwater fish, spotted barbel gudgeon (Squalidus multimaculatus Rosoya et Jeon) from the local river in Yeongdeok, Gyeongsangbuk-do, Korea. The infected fish with bumpy body surface by "yellow grub" showed erratic swimming behavior and some fish were died. The isolated excysted metacercariae were tongue shaped and 2.85~5.89 mm <TEX>${\times}$</TEX> 0.8~1.99 mm in size. 1~98 metacercariae were isolated in individual fish and mean infection intensity was 25. All examined adult spotted barbel gudgeon sizing 7 cm in body length were infected. This is the first report of disease outbreak and mortality caused by C. complanatum infection in wild freshwater fish in Korea.