基于灰色关联分析的海南省农业产业结构优化研究

以2009—2019年海南省农业内部各产业经济数据为样本,采用灰色关联分析法,对当地农业产业结构进行研究。结果表明:海南省农业产业结构同国内外农业产业结构演进趋势相比,存在一定的不足;海南省农业内部各产业与海南省农业总增加值和农民年人均可支配收入均存在极大的相关性,其中牧业与农业总增加值、农林牧渔服务业与农民年人均可支配收入的关联度最高。结合研究结论,提出海南省进一步优化农业内部产业结构建议,以期为海南省优化农业产业结构提供参考。     

Effect of starving and feeding on some haematological and physiological responses of the Nile catfish, <Emphasis Type="Italic">Clarias gariepinus</Emphasis> exposed to copper at extreme seasons

The lethal concentration for 50% of fish for 96h (96h LC₅₀) of copper (Cu²⁺) was estimated for the Nile catfish (Clarias gariepinus) in extreme seasons, winter and summer, 4.31 and 4.79 mg/l, respectively. The Nile catfish was exposed to 96h LC₅₀ of copper for 7 days in extreme winter and summer. The body indices, haematological parameters as well as some plasma and liver enzyme activities and metabolite level were significantly differed in fish exposed to copper over than those of the control fish. Most of the tested parameters were not significantly different between the control fish of winter and summer (winter, water temperature 18 ± 2°C and summer, 27 ± 2°C). The effect of two ration sizes on copper toxicity in two different seasons on C. gariepinus was justified. It was found that the haematological parameters and the tested plasma activities of enzymes were significantly valid due to season differences. The blood parameters as well as plasma activities of enzymes were significantly differed in fishes fed elevated ration (3%) and exposed to copper challenge. On the other hand, the exploit of low feeding ration (0.5%) along with copper exposure during the examined seasons induced non-significant differences of the tested parameters, from those of the corresponding control. Therefore, the low feeding ration provides some tolerance against the possible water-borne copper exposure.     

Determination of the quality parameters of pike perch <Emphasis Type="Italic">Sander lucioperca</Emphasis> caught by gillnet,longline and harpoon in Turkey

ABSTRACT:   The effects of the different catching methods (gillnet, longline, harpoon) on sensory, chemical (pH, total volatile base nitrogen, K -value) and microbiological (total viable count [TVC]) changes in pike perch Sander lucioperca stored in ice were investigated. The same soaking time was used for both gillnet and longline fishing. The catching method had considerable influence on the freshness quality of pike perch. The acceptable shelf life was 15 days for pike perch caught by gillnet, and 22 days for longline and harpoon. The initial concentrations of inosine monophosphate (2.4 μmol/g) in pike perch caught by gillnet were significantly lower ( P  < 0.05) than longline (4.1 μmol/g), and especially by harpoon (16.7 μmol/g). However, the initial K -values for fish caught by harpoon were significantly ( P  < 0.05) lower (24.36%) than fish caught by longline and gillnet (57.69%, 64.41%, respectively). The average K , Ki, G and H -values at rejection day in terms of sensory assessment were approximately 90, 98, 156 and 40%, respectively, for all catching methods during ice storage. However, TVC reached 7.0 log cfu/g after approximately 11 days of storage for fish caught by gillnet, 19 days for fish caught by longline and 8 days for fish caught by harpoon. The result of this study suggests that the best catching method for preserving the freshness of pike perch is longline, based on the data obtained from the sensory and microbiological analysis.     

Post-release movement and diel activity patterns of hatchery-reared and wild black-spot tuskfish <Emphasis Type="Italic">Choerodon schoenleinii</Emphasis> determined by ultrasonic telemetry

ABSTRACT:   Post-release movement and diel activity patterns of hatchery-reared and wild black-spot tuskfish were examined using ultrasonic telemetry. Five hatchery-reared and four wild fish were released in the sandy bottom of Urasoko Bay, Ishigaki Island, Okinawa, Japan, and monitored using automated monitoring receivers from November 2005 to February 2006. Both hatchery-reared and wild fish tended to stay near the release site for over two weeks, before leaving the release site. Both hatchery-reared and wild tuskfish showed diurnal rhythm intermittently; signals were recorded more frequently in the daytime and less frequently in the nighttime, suggesting that the fish of both origins were active during the day and inactive during the night. These findings indicate that the one-year-old hatchery-reared tuskfish have some consistent behavioral characteristics with those of the wild.     

Quantitative analysis of pattern of gonial proliferation during sexual maturation in Japanese scallop <Emphasis Type="Italic">Patinopecten yessoensis</Emphasis>

ABSTRACT:   This study was undertaken to describe and quantitatively analyze the pattern of development of gametes in the Japanese scallop Patinopecten yessoensis . Incorporation of 5-bromo-2'-deoxyuridine (BrdU) into gonial cells was used to quantitatively detect mitotically active gonial cells. Oogonia increased in number from November to December and decreased rapidly to March. A small number of oocytes was detected in November. Oocytes steadily increased in number and size up to March. The number of spermatogonia slightly increased from November to December, and increased markedly from January to March. Both ratios of BrdU-immunopositive gonial cells in the ovary and testis to gonial cells moderately increased from September to December. The ratio of BrdU-immunopositive spermatogonia to gonial cells drastically increased from January to February and kept an elevated level in March, whereas the oogonia started to disappear in January. The results suggest that the pattern of proliferation of gonial cells can be divided into two phases: (i) phase I, oogonia and spermatogonia slowly proliferate through the growing stage; and (ii) phase II, oogonia develop into oocytes and spermatogonia begin to proliferate rapidly through the mature and spawning stages. The proliferation of gonial cells is likely under different endocrine controls in phases I and II.     

控制对虾弧菌病药物的实验研究

研究了一株对虾弧菌病病原菌对２４种药物的敏感性，测定了几种抗菌性较强、抗菌谱较广且价格较低廉的药物对该菌的最低抑菌浓度（ＭＩＣ）和最低杀菌浓度（ＭＢＣ）以及药物在海水环境中对该菌作用的有效性和药物联用效果。结果表明，不同药物具有不同的ＭＩＣ值，在特定的实验条件下，药物之间的作用表现为：协同、拮抗和无关三种结果，不同药物在不海水中作用时间不一。本文对药物滥施乱用的后果进行了讨论并提出了效控制病菌、合     

Evaluation of a real-time polymerase chain reaction assay of the outer membrane protein P2 gene for the detection of Haemophilus parasuis in clinical samples

A real-time polymerase chain reaction (PCR) assay of the outer membrane protein (OMP) P2 gene was developed and used to test 97 putative Haemophilus parasuis pure cultures and 175 clinical tissue samples. With standard culture isolation as the gold standard, the diagnostic sensitivity and specificity of the PCR assay were determined to be 83% and 80%, respectively.     

Prion protein genotypes of sheep as determined from 3343 samples submitted from Ontario and other provinces of Canada from 2005 to 2012

This study analyzed sheep prion protein (PrP) genotypes of samples submitted from Ontario and other provinces of Canada to the Animal Health Laboratory at the University of Guelph, Guelph, Ontario, between 2005 and 2012. In Ontario, the proportion of scrapie-resistant sheep increased from 2005 to 2012 as evidenced by an increase in the ARR haplotype. When Canadian provinces (Alberta, Ontario, Quebec, and Nova Scotia) were compared from 2008 to 2012, a high proportion of scrapie-resistant sheep was found in all the provinces. The proportions of resistant sheep were lower in Alberta and Quebec than in Ontario and Nova Scotia. Alberta had higher proportions of susceptible sheep and a higher frequency of VRQ alleles, and Quebec had a higher frequency of the ARQ allele.     

杜氏藻对盐度的生理反应

1987年从天津汉沽盐场盐池分离培养了数个杜氏藻品系。1989年对其中盐生杜氏藻878和绿色杜氏藻876进行了盐度(分波美度3°、5°、10°、15°和20°5组)试验,试验水温为25±1℃,光照强度约40001x,光照时间10:14(L:D),N∶P∶Fe=20∶2∶1ppm。结果为最大生长量和最大生长率在波美度10°组。盐生杜氏藻878在波美度3°下,藻细胞呈绿黄色,5°和10°下为绿色,15°下为桔黄色,20°下为桔红色。绿色杜氏藻876,在所有的试验盐度下均为绿色。两个品系的细胞大小均随盐度增加而变小。从高盐度(20°Be′)接种到低盐度(3°Be′)适应较快。从低盐度(2.5°Be′)到高盐度(15°Be′)适应较慢。     

浙江农林大学观果植物应用状况调查

对浙江农林大学东湖校区观果植物的应用现状进行了调查与分析,结果表明：在校园内5大区域中,共应用32种观果植物。其中应用频率较多的观果植物为构骨、火棘、南天竹、无刺构骨和黄山栾树。在5大分区中,应用的种类最多的为生活区,共有21种,占总种类数的65．6％;使用频率最高的是无患子,共7次;应用的种类最少的为校内主要道路区块,共9种,占总种类数的28．1％,使用频率最高的是无患子和石楠,分别为3次。在应用方式上,主要用做行道树,与建筑或开花植物结合等形式。