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排序方式: 共有1519条查询结果,搜索用时 31 毫秒
1.
Saddleback-like syndrome is one of the most frequently observed malformations in hatchery-reared red spotted grouper Epinephelus akaara. Saddleback-like syndrome is characterized by a V-shaped dorsal-profile depression behind the head region accompanied by deformities or misalignments of the first to fourth neural spines on the vertebral column and the first to fourth pterygiophores of the dorsal fin. Abnormal swim bladder inflation in several finfish species leads to malformations, particularly of the vertebral column. The present study examined the influence of swim bladder inflation on saddleback-like syndrome in hatchery-reared red spotted grouper. The incidence of saddleback-like syndrome increased as swim bladder inflation rate increased. Additionally, the incidence of saddleback-like syndrome among juveniles with inflated swim bladders was significantly higher than that among juveniles with uninflated swim bladders. The larval swim bladder is located just below the first to fifth vertebrae and the first to fifth dorsal spines, where saddleback-like syndrome occurs. Our results suggest that an inflated swim bladder increases the risk of saddleback-like syndrome in hatchery-reared red spotted grouper. 相似文献
2.
Recreational angling is a popular leisure activity globally and can be a threat or useful conservation tool depending on the management strategy. Miyabe charr Salvelinus malma miyabei is an endemic fish that inhabits Lake Shikaribetsu, and a management program was established to harmonise recreational fishery and conservation. To examine the suitability of this program, population assessment was conducted with the cooperation of anglers. The population size in 2014 as assessed by tag-and-release angling was estimated to be 105,300 [95% confidence interval (CI) 37,300–178,600], much higher than the reported estimate in 1995. Further, angling mortality was estimated to be quite low. Moreover, no decreasing population trend was detected on analysing 8 years of anglers’ catch data. Consequently, angling has facilitated stock assessments of Miyabe charr under the current program. This case is a good example of recreational angling acting as a conservation tool under appropriate management. 相似文献
3.
Fumitaka Kondo Takashi Ohta Toshiharu Iwai Atsushi Ido Chiemi Miura Takeshi Miura 《Fish physiology and biochemistry》2017,43(6):1543-1555
The improvement in feed efficiency is one of the most important subjects in fish culture. The development of feed, in terms of good intake, high growth performance, and high feed efficiency is needed. Squid viscera are one of the candidates for alternative material in improving feed efficiency in fish culture. In the present study, we described the dietary effect of the squid viscera hydrolysate (SVH) on the growth performance of the red sea bream. The addition of SVH to feed caused significant increases in feed intake, fork length, and body weight and produced a marked improvement in feed conversion after 4 weeks of feeding. Furthermore, the results of this feeding revealed that low dietary levels of SVH promote growth performance in the red sea bream. We physiologically analyzed digestion and appetite in fish fed diet containing SVH. SVH promoted the activity of hepatic trypsin and lipase, gene expression of stomach pepsin, hepatic lipase, and pyloric caeca trypsin, thereby improving the nutrient availability in red sea bream. Moreover, the mRNA expression of appetite regulating factor, such as brain NPY and stomach ghrelin was significantly improved by dietary SVH. Our current results indicate that dietary SVH as alternative material produced excellent effects on growth performance, which is dependent on the promoting effect on digestion and appetite in red sea bream. 相似文献
4.
Chiaki Ikeda Yuki Manabe Nami Tomonaga Tatsuya Wada Takashi Maoka Tatsuya Sugawara 《Marine drugs》2020,18(12)
Halocynthiaxanthin is an acetylenic carotenoid mainly found in Halocynthia roretzi. To date, several bioactivities of halocynthiaxanthin have been reported, but its mechanism of digestion and absorption in mammals has not been studied yet. In this study, we evaluated the intestinal absorption of halocynthiaxanthin in mice. The halocynthiaxanthin-rich fraction was prepared from the tunicate Halocynthia roretzi. Mice were orally administered the fraction at a dose of 5 mg/kg body weight. The halocynthiaxanthin levels in the plasma, liver, and small intestine, were quantified using HPLC-PDA, 1, 3, 6, and 9 h after ingestion. The halocynthiaxanthin-rich fraction mainly consisted of the all-trans form and a small amount of cis forms. These three isomers were detected in the plasma of mice 3 h after ingestion. Time-course changes after the ingestion of this fraction were found, with cis isomers being more abundant than the all-trans isomer in the mouse plasma and liver. In the small intestine, however, the all-trans isomer was primarily detected. The possibility that cis isomers might be absorbed rapidly from the small intestine cannot be denied, but our results suggest that dietary all-trans-halocynthiaxanthin might be isomerized to the cis isomer after intestinal absorption. 相似文献
5.
Jeannette S. Bayuelo-Jiménez Takashi Muraoka Eulogio de la Cruz-Torres Esperanza Quintero-Ponce Lydia C. Paredes-Gutiérrez Mohammad Zaman 《Soil Use and Management》2020,36(2):240-249
Land-use change from forest to agriculture in the volcanic ash-derived soils of Mexico has increased over recent decades. It is likely that land uses and management practices, particularly fertilizer use have affected phosphorus (P) distribution and availability. The objective of this study was to evaluate the effects of land-use types (native forest and maize mono-cropping), and the related P addition, on the forms and distribution of soil P and their isotopic exchangeability. An Andisol, sampled from a cropping site, along with the contiguous area under native forest was treated with 32P-labelled potassium phosphate (KH232PO4). The soil samples were extracted after incubation times of 7, 21, 35 and 49 days. Phosphorus content and 32P recovery in fractions sequentially extracted were assessed for each incubation time. Total soil P was dominated by inorganic fractions (79 to 86%) in both land-use types. Resin-Pi, bicarbonate extractable inorganic P (Bic-Pi) and sodium hydroxide extractable inorganic P (NaOH0.1-Pi) were all raised with P addition. However, the proportion of organic P fraction was reduced under cropped soil. The recovery of 32P in soils with P addition indicates that resin-Pi, Bic-Pi and NaOH0.1-Pi comprised nearly all the exchangeable P. In native soils with no P addition, more than 19% of the 32P was recovered in Bic-Po and NaOH0.1-Po forms. This finding indicates that organic P cycling is crucial when soil Pi reserves are presented in an inadequate amount. Ecologically based management has to be designed for replenishment and succeeding maintenance of soil organic P compounds to increase sustainable agricultural production. 相似文献
6.
Tomoya TAKAHASHI Akihiro MORI Hitomi ODA Isao MURAYAMA Mitsuhiko KOUNO Toshinori SAKO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(2):260
Changes in lipoprotein profiles occur in dairy cows during the periparturient period and in cows with transition cow disease. Here, the lipoprotein profiles of Holstein–Friesian dairy cows during the periparturient period were obtained by anion-exchange, high-performance liquid chromatography to evaluate the usefulness of lipoprotein profile evaluation during the periparturient period and in cows with fatty liver and milk fever. Lipoprotein levels (including total and high- (HDL-C) and low-density lipoprotein (LDL-C) cholesterol) in 10 healthy cows were low 4 weeks prepartum, with the lowest values at calving or within 1 week of calving; the values increased at 8 weeks postpartum. The lipoprotein levels were measured in 16 cows diagnosed with fatty liver (n=10) or milk fever (n=6) and compared to 10 healthy dairy cows. A significant difference was observed in HDL-C between healthy cows (at calving and 1 week postpartum), and the fatty liver and milk fever cows. Cows with fatty liver and milk fever had a lower mean HDL-C than the 10 healthy dairy cows at calving and 1 week postpartum. HDL-C might be a good indicator of energy balance for differentiating healthy cows from those with transition cow disease. 相似文献
7.
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment in an aerobic bioreactor packed with carbon fibers 下载免费PDF全文
Takahiro Yamashita Ryoko Yamamoto‐Ikemoto Hiroshi Yokoyama Hirofumi Kawahara Akifumi Ogino Takashi Osada 《Animal Science Journal》2015,86(3):358-368
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N2O emission and avoiding NOx (NO3 + NO2) accumulation. The N2O emission factor was 0.0003 g N2O‐N/gTN‐load in the CF bioreactor compared to 0.03 gN2O‐N/gTN‐load in an activated sludge reactor (AS reactor). N2O and CH4 emissions from the CF reactor were 42 g‐CO2 eq/m3/day, while those from the AS reactor were 725 g‐CO2 eq/m3/day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH4‐N, and accumulated an average of 14 mg/L of the NO3‐N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH4‐N and accumulated an average 183 mg/L of the NO3‐N. NO2‐N was almost undetectable in both reactors. 相似文献
8.
Masahiro MIYABE Azusa GIN Eri ONOZAWA Mana DAIMON Hana YAMADA Hitomi ODA Akihiro MORI Yutaka MOMOTA Daigo AZAKAMI Ichiro YAMAMOTO Mariko MOCHIZUKI Toshinori SAKO Katsutoshi TAMURA Katsumi ISHIOKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1201-1206
G protein-coupled receptor (GPR) 120 is an unsaturated fatty acid receptor, which is
associated with various physiological functions. It is reported that the genetic variant
of GPR120, p.Arg270His, is detected more in obese people, and this genetic variation
functionally relates to obesity in humans. Obesity is a common nutritional disorder also
in dogs, but the genetic factors have not ever been identified in dogs. In this study, we
investigated the molecular structure of canine GPR120 and searched for candidate genetic
variants which may relate to obesity in dogs. Canine GPR120 was highly homologous to those
of other species, and seven transmembrane domains and two N-glycosylation sites were
conserved. GPR120 mRNA was expressed in lung, jejunum, ileum, colon, hypothalamus,
hippocampus, spinal cord, bone marrow, dermis and white adipose tissues in dogs, as those
in mice and humans. Genetic variants of GPR120 were explored in client-owned 141 dogs,
resulting in that 5 synonymous and 4 non-synonymous variants were found. The variant
c.595C>A (p.Pro199Thr) was found in 40 dogs, and the gene frequency was significantly
higher in dogs with higher body condition scores, i.e. 0.320 in BCS4–5 dogs, 0.175 in BCS3
dogs and 0.000 in BCS2 dogs. We conclude that c.595C>A (p.Pro199Thr) is a candidate
variant relating to obesity, which may be helpful for nutritional management of dogs. 相似文献
9.
Shuhei ENJOJI Ryotaro YABE Nobuyuki FUJIWARA Shunya TSUJI Michael P. VITEK Takuya MIZUNO Takayuki NAKAGAWA Tatsuya USUI Takashi OHAMA Koichi SATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1451-1456
Canine melanoma is one of the most important diseases in small animal medicine.
Protein phosphatase 2A (PP2A), a well conserved serine/threonine phosphatase, plays a
critical role as a tumor suppressor. SET/I2PP2A is an endogenous inhibitor for PP2A, which
directly binds to PP2A and suppresses its phosphatase activity. Elevated SET protein
levels have been reported to exacerbate human tumor progression. The role of SET in canine
melanoma, however, has not been understood. Here, we investigated the potential
therapeutic role for SET inhibitors in canine melanoma. The expression of SET protein was
observed in 6 canine melanoma cell lines. We used CMeC-1 cells (primary origin) and CMeC-2
cells (metastatic origin) to generate cell lines stably expressing SET-targeting shRNAs.
Knockdown of SET expression in CMeC-2, but not in CMeC-1, leads to decreased cell
proliferation, invasion and colony formation. Phosphorylation level of p70 S6 kinase was
decreased by SET knockdown in CMeC-2, suggesting the involvement of mTOR (mammalian target
of rapamycin)/p70 S6 kinase signaling. The SET inhibitors, OP449 and FTY720, more
effectively killed CMeC-2 than CMeC-1. We observed PP2A activation in CMeC-2 treated with
OP449 and FTY720. These results demonstrated the potential therapeutic application of SET
inhibitors for canine melanoma. 相似文献
10.
Kazuhiko ARAHARA Takashi MATSUMOTO Fumiki MORIMATSU Katsuhiko ARAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1503-1506
In this study, the effect of fibronectin on the neurite outgrowth from embryoid
bodies (EBs) in neurodifferentiated embryonal carcinoma P19 cells was examined. The
neurite outgrowth on fibronectin was maintained for a longer time in comparison with those
on collagen or laminin. Quantitative RT-PCR revealed that mRNA level corresponding to
sonic hedgehog (Shh) in neurodifferentiated P19 cells was upregulated on fibronectin,
whereas collagen or laminin did not affect. Further knockdown of integrin αv subunit in
P19 cells demonstrated that expression of Shh was mediated through interaction between
fibronectin and integrin. Additionally, exogenous Shh agonist accelerated neurite
outgrowth from embryonic stem cell-derived EBs without large change of neuronal phenotype
expression. Taken together, fibronectin could maintain neurite outgrowth via increased Shh
expression. 相似文献