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31.
32.
Peter M. Visscher Naomi R. Wray Chris S. Haley 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(4):273-278
Through his own research contributions on the modelling and genetic analysis of quantitative traits and through his former students and postdocs, Robin Thompson has indirectly left a major legacy in human genetics. In this short note, we highlight examples of the long‐lasting relevance and impact of Robin's work in human genetics. A lone early study of marker‐assisted selection developed many of the tools and approaches later exploited (often after reinvention) by the human genetics community in GWAS studies and for prediction. Furthermore, a particularly clear example of the pervasive impact of Robin's work is that REML has become the default method to estimate variance components and that genetic predictions exploiting linkage disequilibrium in the population are starting to become used in precision medicine applications. 相似文献
33.
黄金鲈与伊犁鲈杂交后代在气提泵循环水养殖系统中生长分析 总被引:1,自引:0,他引:1
研究通过黄金鲈(Perca flavescens)雌鱼与伊犁鲈(Perca schrenki)雄鱼进行杂交,以期加快鲈鱼的生长速度,推迟其性成熟和提高上市规格.为减少饲养环境条件和人为管理差异造成生长试验误差,研究采用试验鱼同池混养的方法进行生长比较.在气提泵循环水养殖系统中,经690 d的生长比较试验.结果表明:杂交鲈体重增长比黄金鲈快33.91%;杂交鲈的性腺发育被推迟或性腺发育不良;黄金鲈和杂交鲈的成活率分别为87.50%和82.08%,二者在成活率上无显著差异(P=0.29).杂交鲈适宜在高密度循环水养殖条件下生长,杂交优势较为显著,可以取代黄金鲈进行集约化养殖生产. 相似文献
34.
Akihiro Okamura Hideo P. Oka Noriyuki Horie Tomoko Utoh Yoshiaki Yamada Naomi Mikawa Satoru Tanaka Katsumi Tsukamoto 《Aquaculture International》2009,17(1):91-99
For efficient production of Japanese eel Anguilla japonica eggs, knowledge of the status of the sexual maturity of potential broodstock females is important because this status directly
influences the time required to produce mature eggs by successive hormone doses. Here we apply an eye index (relative eye
size) to evaluate the gonadal status of feminized A. japonica, which were induced by administration of estradiol-17β. Examination of gonad somatic and eye indexes of 267 feminized eels,
cultivated for 12–56 months, revealed a significant correlation between these two indexes. Artificial maturation of 35 feminized
eels showed that the number of hormone injections administered before ovulation was significantly lower as the eye index score
increased, indicating availability of this noninvasive method of predicting sexual maturity of feminized eel. There was no
correlation between eye index and fertilization rate, hatching rate, or larval survival rate, suggesting that sexual maturity
before hormonal treatment does not affect egg quality. 相似文献
35.
Akihiro Okamura Yoshiaki Yamada Naomi Mikawa Noriyuki Horie Katsumi Tsukamoto 《Aquaculture International》2016,24(2):549-555
One of the difficulties to rear Anguilla japonica larvae is the frequent occurrence of notochord deformities. We tested the effect of salinity on the occurrence of the deformities, because we have been using 50 % diluted seawater (50 % SW) for glass eel production, on the basis of the fact that intermediate salinity saves energy due to lower cost for osmoregulation and contributes higher survival and growth rates. We reared 6-day-old larvae in 50 and 100 % SW for 85 days and observed their morphology. The occurrence rate of deformed larvae, including kyphosis and scoliosis, was significantly higher in 50 % SW (35.8 %) than in 100 % SW (25.4 %), while survival rate was significantly higher in 50 % SW (69.8 %) than in 100 % SW (32.3 %) and growth in 50 % SW (mean body depth: 7.9 ± 5.3 mm) was better than in 100 % SW (6.8 ± 4.6 mm). We speculate that the most of severely deformed larvae could not survive in the tougher condition of 100 % SW, showing the lower occurrence of deformed larvae. Eventually, the yield of normal larvae after 85 days rearing was 1.9-fold higher in 50 % SW than in 100 % SW, implying that the advantage of 50 % SW for rearing eel larvae outweighs the risk of deformities. 相似文献
36.
Tatsuo Kawarasaki Satoko Enya Masayoshi Otake Masatoshi Shibata Satoshi Mikawa 《Animal Science Journal》2017,88(11):1801-1810
To assess the performance of boars derived by somatic cell cloning, we analyzed various aspects of their reproductive characteristics and the expression of two imprinted genes. Cloned boars (cloned Duroc × Jinhua) were analyzed for birth weight, growth rate, age at first ejaculation, semen characteristics and fertility, in comparison with naturally bred control boars of the same strain. The expression of imprinted genes was analyzed using the microsatellite marker SWC9 for the paternally expressed gene insulin‐like growth factor ‐2 (IGF2) and with single nucleotide polymorphisms (SNPs) for the gene maternally expressed 3 (MEG3). The cloned boars had high production of semen and were nearly equal in level of fertility to conventional pigs; they showed similar characteristics as naturally bred boars of the same strains. The expression of IGF2 was partially disturbed, but this disturbed expression was not linked to a change in developmental fate or reproductive performance. These results indicate that use of cloned boars could be highly effective for proliferation of pigs with desirable characteristics, preservation of genetic resources and risk reduction against epidemic diseases, such as foot‐and‐mouth disease, through storage of somatic cells as a precautionary measure for use in regenerating pig populations after a future pandemic. 相似文献
37.
A 2-year-old male intact Belgian Malinois was presented for exercise intolerance. A grade III/VI left basilar systolic murmur was detected. Echocardiography revealed moderate right atrial and ventricular dilation and increased pulmonic outflow velocity. Thoracic radiographs showed right heart enlargement and a dilated caudal vena cava. In addition, on the left lateral projection, an enlarged aberrant right cranial pulmonary lobar vein was suspected to be diverging ventrally from the course of the right cranial lobar bronchus and inserting more ventrally than normal in the region of the right atrium. A left-to-right pulmonary vascular shunt was suspected, and the patient underwent further diagnostics under general anesthesia. An agitated saline study was positive, suggestive of a concurrent right to left shunt. A right heart catheterization was performed. Angiography was inconclusive. Oximetry testing revealed an increase in oxygen saturation within the right atrium at the level of the caudal cava supportive of a left-to-right shunt in this region. Computed tomography angiography revealed a large single pulmonary vein that anomalously entered into the caudolateral aspect of the right atrium (left-to-right shunt) and was suspicious for a small arteriovenous malformation between the right caudal pulmonary artery and the right pulmonary vein returning to the left atrium (right to left shunt). The patient was diagnosed with a partial anomalous pulmonary venous connection and a possible arteriovenous malformation. 相似文献
38.
Junya ITO Tomoko YOSHIDA Yasushi KASAI Takuya WAKAI Jan B. PARYS Rafael A. FISSORE Naomi KASHIWAZAKI 《Animal Science Journal》2010,81(1):34-41
During fertilization in mammalian species, a sperm-induced intracellular Ca2+ signal ([Ca2+ ]i ) mediates both exit of meiosis and oocyte activation. Recently, we demonstrated in mouse oocytes that the phosphorylation levels of inositol 1,4,5 trisphosphate receptor type1 (IP3 R1), the channel responsible for Ca2+ release and oscillations during fertilization, changed during maturation and fertilization. Therefore, we examined the expression and phosphorylation of IP3 R1 during in vitro maturation of pig oocytes. Here, our present study shows that expression of IP3 R1 protein did not change during maturation, although the phosphorylation status of the receptor, specifically at an MPM-2 epitope, did. We found that while at the beginning of maturation IP3 R1 lacked MPM-2 immunoreactivity, it became MPM-2 reactive by 24 h and reached maximal reactivity by 36 h. Interestingly, the acquisition of MPM-2 reactivity coincided with the activation of p34cdc2 kinase and mitogen-activated protein kinase (MAPK), which are involved in meiotic progression. Following completion of maturation, inactivation of MAPK by U0126 did not affect IP3 R1 phosphorylation, although inactivation of p34cdc2 kinase by roscovitine dramatically reduced IP3 R1 phosphorylation. Neither inhibitor affected total expression of IP3 R1. Altogether, our results show that IP3 R1 undergoes dynamic phosphorylation during maturation and this might underlie the generation of oscillations at fertilization. 相似文献
39.
Geertje M.F. van der Heijden Ted R. Feldpausch Ana de la Fuente Herrero Naomi K. van der Velden Oliver L. Phillips 《Forest Ecology and Management》2010
Lianas hold an important, but understudied, role in forest dynamics, however they are difficult to measure and detailed liana measurements are time consuming. Many researchers have therefore used an ordinal scale index, the crown occupancy index (COI), to describe the liana load carried by trees. Here we assess the overall effectiveness, in terms of accuracy, precision, repeatability and efficiency, of the COI in tropical forests. We relate the COI to more detailed liana measurements at the individual tree-level and site-level, comparing sites with different levels of liana infestation. Our results show (1) that the COI accurately measures individual tree and plot level liana loads, indicated by the strong correlations between the COI and the number and basal area of lianas. However, (2) as expected, the COI is only weakly related to the basal area of lianas rooted close to the tree, which is a proxy for competition for below-ground resources. The COI is also (3) an efficient measure of liana loads, as the input time needed for a COI survey is considerably less than that of a detailed liana survey. We also (4) found a high degree of repeatability in COI classification between observers. Additionally (5), the COI can be used to differentiate between sites in terms of their overall liana canopy competition (precision), but (6) may not be a precise indicator of the site-level mean basal area of lianas in tree crowns. 相似文献
40.
Abe N Okuhira M Tsutsui C Murata Y Nakamura Y 《Journal of agricultural and food chemistry》2012,60(7):1887-1892
In the present study, we examined the toxicity of benzyl ITC (BITC) and its urinary mercapturic acid metabolite (BITC-NAC), using a normal renal proximal tubular cell line, pig LLC-PK1. BITC increased cell death with an IC(50) value of about 7 μM, whereas the cytotoxic effect of BITC-NAC was five times weaker than that of BITC. We observed a significant necrosis of the compounds on LLC-PK1 cells with oxidative stress. In the presence of 5 mM glutathione (GSH), comparable to physiological levels, the cytotoxicity of BITC-NAC as well as BITC was significantly reduced. Furthermore, the increase in intracellular GSH levels by pretreatment with NAC before the BITC treatment resulted in inhibition of the BITC-induced necrotic events as well as intracellular oxidative stress. These results suggest that GSH is a determinant of cellular resistance against the BITC-mediated and oxidative stress-dependent cytotoxicity in renal proximal tubular cells. 相似文献