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排序方式: 共有542条查询结果,搜索用时 31 毫秒
1.
Mark D. Rawling Nicola Pontefract Ana Rodiles Ilektra Anagnostara Eric Leclercq Marion Schiavone Mathieu Castex Daniel L. Merrifield 《Journal of the World Aquaculture Society》2019,50(6):1108-1122
Fish were fed a single‐strain yeast fraction (SsYF; 2 g/kg) or a multistrain yeast fraction (MsYF; 0.8 g/kg) for 10 weeks. The results demonstrated significant (p ≤ 0.03) elevations in weight gain, specific growth rate, protein efficiency ratio, and feed conversion ratio in fish fed the yeast fraction‐supplemented diets. In the distal intestine, a significant elevation in microvilli density was observed after 5 and 10 weeks of dietary supplementation with MsYF and SsYF, respectively, compared to control fed fish (p < 0.001). A significant elevation (p = 0.02) in the perimeter ratio was observed in fish fed diets supplemented with the yeast fractions. After 10 weeks of feeding on the experimental diets, Rt‐qPCR demonstrated a significant downregulation (p < 0.05) in the stress response genes, heat‐shock protein 70 (hsp70) and proliferating cell nuclear antigen (pcna), in fish fed diets supplemented with the yeast fractions. Significant (p < 0.05) elevations in interleukin 1‐beta (il1β) and interleukin‐10 (il10) gene expression were observed in fish fed diets supplemented with the MsYF compared to the other dietary groups. These findings suggest that feeding an MsYF specifically at a lower incorporation rate < 1 g/kg, compared to a commercial SsYF at 2 g/kg, is effective in improving the intestinal health status and growth performance of European seabass. 相似文献
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Effects of five cryoprotectants on proliferation and differentiation‐related gene expression of frozen‐thawed bovine calf testicular tissue
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Hao Li Yi‐Lin Bian Nicola Schreurs Xiao‐Gang Zhang Sayed Haidar Abbas Raza Qian Fang Li‐Qiang Wang Jian‐Hong Hu 《Reproduction in domestic animals》2018,53(5):1211-1218
The cryopreservation of testicular tissue is a potential method for preserving male fertility. However, the effect of cryopreservation on bovine calf testicular tissue is scarce. This study investigated the effect of different cryoprotectants on bovine calf testicular tissue at the molecular level. Testicular tissue from ten immature bovine calves (6 months) was collected after slaughter and cryopreserved in an extender containing different concentrations of the following five cryopreservation solutions (CP): bovine serum albumin (BSA) with 5% dimethyl sulfoxide (DMSO), trehalose with 5% DMSO, DMSO and glycerol and ethylene glycol (EG). After 7‐day cryopreservation, the expression levels of three spermatogonial stem cell (SSC)‐related genes, octamer‐4 (OCT4), KIT ligand (MGF/SCF) and kit oncogene (C‐KIT), were investigated by quantitative PCR (qPCR). The cell viability was highest for the tissues preserved with 30 mg/ml BSA (77.82% ± 1.22) and 40 mg/ml trehalose (74.23% ± 1.16) compared with other groups (p < 0.05), and the level of expression of the three genes was highest with 30 mg/ml BSA (p < 0.05). Compared with other CPs, the 30 mg/ml BSA and 40 mg/ml trehalose have the better cryopreserve protection. The 30 mg/ml BSA is the most viable media for the cryopreservation of testicular tissue from cattle. 相似文献
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Andrew T. Willis Samantha Barnum Nicola Pusterla 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(1):51
This study aimed to validate a point-of-care polymerase chain reaction (PCR) assay for detection of Streptococcus equi subsp. equi (S. equi) in rostral nasal swabs from horses with suspected acute strangles and to compare the results against the molecular gold standard of quantitative polymerase chain reaction (qPCR). Two hundred thirty-two individual swabs of rostral nasal passages were characterized by qPCR as S. equi positive, S. equi subsp. zooepidemicus (S. zooepidemicus) positive, or S. equi and S. zooepidemicus negative. The specificity and sensitivity of the point-of-care PCR assay were 89% and 84%, respectively. The limits of detection of the qPCR assay and the point-of-care PCR analyzer were 3 and 277 eqbE target genes of S. equi, respectively. Overall agreement and short turnaround time make the point-of-care PCR assay a potential molecular diagnostic platform that will enhance the capability of equine veterinarians to timely support a diagnosis of strangles and institute proper biosecurity protocols. 相似文献
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da Silva Isadora Gonçalves Castoldi Renata de Oliveira Charlo Hamilton César de Souza Miranda Mateus Nunes Thaíssa Dias Cardoso Costa Luciene Lacerda Lemes Ernane Miranda 《Journal of Crop Science and Biotechnology》2020,23(2):191-196
Journal of Crop Science and Biotechnology - The cultivation of sweet corn is expanding in Brazil, but there are serious constraints about the availability of commercial cultivars. The selection of... 相似文献
8.
Alejandro Merchn Judith Koenig Nathalie Ct Nicola Cribb Gabrielle Monteith 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(1):74
The objective of this retrospective study was to determine the occurrence of joint-related complications after elective arthroscopy of the tibiotarsal joint (TTJ) in 329 horses, and the association with specific clinical parameters. Data were collected from medical records of horses undergoing elective tibiotarsal joint arthroscopy for fragment removal. Exact conditional univariate regression was used to determine significant risk factors for joint-related post-operative complications.Of 485 joints, 2 (0.4%) developed surgical site infection, 4 (0.8%) developed septic arthritis, 1 (0.2%) developed synovial fistula. There was a significantly increased odds of having septic arthritis as height and length of the distal intermediate ridge of the tibia (DIRT) lesion increased. The median height and length of the DIRT fragments in affected cases was 13.5 mm and 18.0 mm, respectively. For each unit (1 mm) increase in height, there was a 42% increase in the risk of septic arthritis occurrence (P = 0.0042), and a 15% increase for each unit increase in length (P = 0.035). Horses were significantly less likely to develop septic arthritis when suture smaller than USP 0 was used.Horses with larger osteochondritis dissecans lesions of the DIRT region have an increased risk of developing septic arthritis following fragment removal. 相似文献
9.
Confronting collinearity: comparing methods for disentangling the effects of habitat loss and fragmentation 总被引:1,自引:1,他引:0
Adam C. Smith Nicola Koper Charles M. Francis Lenore Fahrig 《Landscape Ecology》2009,24(10):1271-1285
Estimating the relative importance of habitat loss and fragmentation is necessary to estimate the potential benefits of specific
management actions and to ensure that limited conservation resources are used efficiently. However, estimating relative effects
is complicated because the two processes are highly correlated. Previous studies have used a wide variety of statistical methods
to separate their effects and we speculated that the published results may have been influenced by the methods used. We used
simulations to determine whether, under identical conditions, the following 7 methods generate different estimates of relative
importance for realistically correlated landscape predictors: residual regression, model or variable selection, averaged coefficients
from all supported models, summed Akaike weights, classical variance partitioning, hierarchical variance partitioning, and
a multiple regression model with no adjustments for collinearity. We found that different methods generated different rankings
of the predictors and that some metrics were strongly biased. Residual regression and variance partitioning were highly biased
by correlations among predictors and the bias depended on the direction of a predictor’s effect (positive vs. negative). Our
results suggest that many efforts to deal with the correlation between amount and fragmentation may have done more harm than
good. If confounding effects are controlled and adequate thought is given to the ecological mechanisms behind modeled predictors,
then standardized partial regression coefficients are unbiased estimates of the relative importance of amount and fragmentation,
even when predictors are highly correlated. 相似文献
10.
Luca Ceriola Paolo Accadia Piero Mannini Fabio Massa Nicoletta Milone Nicola Ungaro 《Fisheries Research》2008,92(2-3):255-267
The state of demersal fishery in the Southern Adriatic Sea (GFCM-GSA 18, Central Mediterranean), years 1996–2003, from a biological, social and economic point of view was analysed using 47 indicators: 22 biological indicators obtained from fishery-independent data through yearly experimental bottom trawl surveys (“Medits” Programme), and 25 socio-economic indicators estimated from fishery-dependent data, available from the monitoring system of the Italian Institute for Economic Research on Fisheries and Aquaculture (IREPA). Biological indicators were applied for “single-species” (Eledone cirrhosa, E. moschata, Illex coindetti, Merluccius merluccius, Mullus barbatus, Nephrops norvegicus, Parapenaeus longirostris, Raja clavata, Zeus faber) and for “multi-species” analysis. Economic indicators describing economic performance, productivity, costs and prices, and the overall economic sustainability of fishery were estimated. Social indicators and a general indicator summarising social sustainability were also considered. Indicators’ values were displayed using the Traffic Light system. Both fishery-independent and fishery-dependent indicators highlighted a progressive decline of the trawl fishery system in the GSA 18. This decline was mainly related to the ongoing depletion of the traditional fishery target species (mostly long-living, late-maturing species) partially replaced by the increase of traditional accessory species (generally short-living species), as well as to the reduction of productivity and increasing costs. The whole procedure was proposed as a contribution to the identification and applicability of bio-economic indicators for fishery management purposes. 相似文献