海水贝类苗种循环水培育水处理技术的研究与应用

封闭循环水育苗作为一种高技术育苗模式,其核心是养殖废水的净化处理。对于循环水系统的每一道处理工序,都有大量可选择的工艺。本试验利用自建的100 m3的海湾扇贝苗种封闭循环水培育系统,通过用各个阶段的出水养殖扇贝幼体,以及测定出水指标等来判断水处理系统的处理效果。结果表明,封闭循环水处理系统的效果是成功的。     

The effects of scallop shell extract on collagen synthesis

ABSTRACT:   Previous observations showed that scallop shells contain organic components that have various useful applications for skin. In this study, the effect of the organic components of scallop shell (scallop shell extract) on collagen metabolism is investigated. Collagen metabolism is tightly controlled by the collagen degrading matrix metalloproteinases (MMP) and their tissue inhibitors (TIMP). Treatment of human skin fibroblast cells with the scallop shell extract increased the mRNA expression levels of type I collagen, MMP-1 and TIMP-1, suggesting that the scallop shell extract may activate collagen metabolism in skin fibroblast cells. Sirius red staining and the colorimetric quantification of collagen in fibroblast cells demonstrated that the scallop shell extract increased collagen content by approximately 1.3-fold. In vivo studies also revealed that the topical application of the scallop shell extract to rat dorsal skin increased the collagen content in the skin tissue section. These results suggest that the scallop shell extract may be effective for the treatment of photoaged and aging skin, which undergo collagen loss.     

单胺类及5-羟色胺拮抗剂对海湾扇贝幼虫生长的影响

单胺类药物左旋多巴胺和5-羟色胺一方面可能促进海湾扇贝幼虫纤毛活动从而促进幼虫摄食,另一方面引起纤毛运动强度的改变,又影响幼虫的能量消耗,因此对扇贝幼虫的生长可能存在着双重影响。以海湾扇贝幼虫为研究对象,探讨了左旋多巴胺和5-羟色胺及5-羟色胺的两种拮抗剂曲唑酮和赛庚啶对其生长的影响及其可能的作用机制。试验结果表明,0.1ng/L左旋多巴胺和1.0ng/L 5-羟色胺对海湾扇贝幼体的生长率促进作用最强,而5-羟色胺的促生长作用可被曲唑酮和赛庚啶抑制,说明5-羟色胺可能是通过5-HT1或5-HT2型受体起作用的。在海湾扇贝的育苗实践中可以选择使用低质量浓度的5-羟色胺以促进幼虫的生长。     

玉米秸青贮和皇草青贮营养价值的比较研究

江西省地处亚热带季风气候区,春夏季节雨水充沛,牧草生长旺盛,产草量高,饲草供应充足,而在秋末至春初,由于秋季干旱和冬季寒冷的影响,牧草供应则较为短缺。因此,饲草的周年充足供应问题成了山西省肉牛生产中一个急待解决的课题,而牧草的调制(青贮和干草晒制)可以将旺季多余的牧草贮藏起来以保证牛在饲草短缺季节有充足的草料供应。与其它的调制方法相比,从营养价值方面考虑将牧草进行青贮似乎更具有优势,它可以减少营养物质的损失。本研究分别用玉米青贮料和皇草青贮料作为生长肉牛的基础饲料以比较它们各自的营养价值。     

Using a biophysical model to investigate connectivity between spawning grounds and nursery areas of King George whiting (Sillaginodes punctatus: Perciformes) in South Australia’s gulfs

Many demersal marine fish species depend on a dispersive larval stage that connects geographically discrete sub‐populations. Understanding connectivity between these sub‐populations is necessary to determine stock structure, which identifies the appropriate spatial scale for fishery management. Such connectivity is poorly understood for King George whiting (Sillaginodes punctatus; Perciformes) in South Australia's gulf system, even though spawning grounds and nursery areas are adequately defined. In response to declines in commercial catches and estimated biomass, this study aimed to determine the most important spawning grounds and nursery areas to recruitment, and the connectivity between them. A biophysical model was seeded with particles according to the distribution and density of eggs throughout the spawning area in 2017 and 2018. Despite inter‐annual differences in the origins of particles, dispersal pathways and predicted settlement areas remained consistent between years. Predicted settlement was generally highest to nursery areas only short distances from regional spawning grounds, consistent with previous hydrodynamic models. However, the model also predicted that spawning in one region could contribute to recruitment in an adjacent region later in the spawning season, which aligned with the breakdown of thermohaline fronts at the entrance of each gulf. The connectivity between spawning grounds and nursery areas predicted by the model is supported by spatio‐temporal patterns in the otolith chemistry of pre‐flexion larvae and settled juveniles. Consequently, the most parsimonious explanation is that the populations of King George whiting in South Australia's gulf system constitute a single, panmictic stock, which has implications for fishery management.     

LEFT ATRIAL TO AORTIC ROOT INDICES USING TWO-DIMENSIONAL AND M-MODE ECHOCARDIOGRAPHY IN CAVALIER KING CHARLES SPANIELS WITH AND WITHOUT LEFT ATRIAL ENLARGEMENT

Two-dimensional (2-D) echocardiographic measurement of the left atrium (LA) has the potential to be more accurate than the standard M-mode method, because the LA body can be measured. We evaluated a 2-D method for measuring LA and aorta (AO) in a right parasternal short-axis view and compared it to the M-mode method. An index for LA size (LA/AO) was calculated in 166 cavalier King Charles spaniels, 56 normal and 110 dogs with mitral regurgitation (MR) of varying degrees secondary to chronic valvular disease. In normal dogs, the AO-2-D and LA/AO-2-D did not correlate to body weight (BW) or BW2; whereas, all M-mode values and the LA-2-D were significantly (p < .05) related to both BW parameters. In normal dogs, there was no difference between M-mode and 2-D indices. For all dogs (normal and dogs with MR) there was an 11% bias between the M-mode and 2-D index with the LA/AO-2-D being higher than the LA/AO-M. The association between the mean and the difference of the indices demonstrated a quadratic relationship. Dogs with a mean LA/AO of 2.0-2.5 showed the largest difference between the two indices. Small values for the 2-D coefficients of variation for respiration and stage of diastole were found; 3.4 and 3.1%, respectively. The 2-D index is more sensitive to LA enlargement than the M-mode index.     

‘热研4号’王草替代紫花苜蓿对TMR发酵品质及有氧稳定性的影响

本试验旨在探讨不同比例‘热研4号’王草（Pennisetum purpureum×P.americana ‘Reyan No.4’）替代紫花苜蓿（Medicago sativa L.）对全混合日粮发酵品质及有氧稳定性的影响。试验设‘热研4号’王草替代比例为0%（H₀,紫花苜蓿对照组）,18%（H₁₈）,30%（H₃₀）,42%（H₄₂）4个处理,青贮60 d后开袋取样,分析其发酵品质和营养成分,并分别在有氧暴露的第0,3,6,9,12 d取样评定其有氧稳定性。结果表明：随着热研4号王草替代比例的增加,发酵全混合日粮中乳酸含量、pH及氨态氮/总氮逐渐减小,各组氨态氮/总氮小于100 g·kg^-1TN且均未检测到丁酸;发酵60d后,H₄₂组水溶性碳水化合物含量显著高于H₀,H₁₈组（P<0.05）,与发酵前相比,各组干物质和粗蛋白含量有所下降,H₄₂组干物质和粗蛋白含量下降最小;有氧暴露期间,好氧细菌、酵母菌和霉菌的数量逐渐增加,乳酸菌的数量逐渐降低,H₄₂组pH在12 d内未超过4.2,有氧稳定性最好。由经济效益分析可知,H₄₂组饲料成本最低。综上所述,选用H₄₂组进行全混合日粮发酵最为适宜。     

海湾扇贝性腺发育的生物学零度

性腺发育的生物学零度是生物的繁殖习性和生物积温研究中的一个重要指标。正如菊地省吾提出皱纹盘鲍性腺发育的生物学零度以后,人们已可以通过控制积温的方法有效地预报和控制鲍鱼的产卵。因此研究海湾扇贝性腺发育的生物学零度,在海湾扇贝的繁殖理论研究以及海湾扇贝的工厂化人     

Experimental collection of great scallop postlarvae and other benthic species in the Bay of Brest: settlement patterns in relation to spatio-temporal variability of environmental factors

Settlement patterns of great scallop (Pecten maximus) postlarvae and other benthic species in the Bay of Brest were studied from 2-D and 3-D collectors to clarify biotic interactions at the postlarval stage. Plane tiles became colonized mainly by epifaunal suspension feeders, while the 3-D substrata collected a more diverse fauna. Both species diversity and total abundance were higher in Netlon bags, compared with sandstone tiles. However, hydroids, bryozoans, tubicolous polychaetes, a number of epifaunal molluscs and macroalgae were more abundant on tiles. Between-sites differences in taxonomic group abundances mostly reflected the benthic fauna and flora beneath the collectors and would be explained by differential settlement and survival, according to local environmental conditions. Sediment type, depth, salinity, water turbulence, food and biotic interactions would be the factors regulating settlement. Bryozoans, hydrozoans, Anomia ephippium, Crepidula fornicata, mussels, tubicolous polychaetes, Pisidia longicornis, Hiatella arctica, Aequipecten opercularis and Chlamys varia were the main potential competitors of Pecten maximus collected. Crabs and Nassaridae would account for most of the potential scallop predators. Possible ways of improving scallop spat collection and cultivation are discussed with reference to the efficiency and placement of collectors, to environmental characteristics and to the intensity of biotic interactions at the postlarval stage.