吡喹酮对鲤鱼感染台湾棘带吸虫后期囊幼虫的防治效果

[目的]探讨3种不同药物处理方式对台湾棘带吸虫引起的鲤鱼幼鱼急性鱼鳃传染病(开放性鳃病)的防治效果.[方法]在试验初期,将1620条鲤鱼幼鱼(70日龄)鱼鳃自然感染台湾棘带吸虫,随后分成4组,分别采用CuSO4、福尔马林和吡喹酮不同方式处理6周,与对照(自然喂食、不使用任何化学药剂)比较防治鲤鱼幼鱼急性鳃传染病的效果.[结果]感染台湾棘带吸虫的幼鱼生长缓慢,其身长和体重增长均较慢.施药后,幼鱼台湾棘带吸虫后期囊幼虫感染强度减少.在每千克饲料中分别添加50和75 mg吡喹酮喂食幼鱼5d,可以杀死鱼鳃中所有的台湾棘带吸虫后期囊幼虫,且鱼鳃恢复正常;面使用25 mg吡喹酮,仅有35%的后期囊幼虫死亡.所有不同浓度CuSO4处理(0.3、0.4和0.5mg/kg冲洗浸泡24 h及以3.0、4.0和5.0 mg/kg冲洗浸泡10m)和福尔马林处理(20、25和30 mg/kg冲洗浸泡及200、250和300 mg/kg短时间冲洗浸泡)均不能杀死台湾棘带吸虫后期囊幼虫.[结论]经普通化学药剂CuSO4或福尔马林冲洗浸泡,不能防治由台湾棘带吸虫后期囊幼虫引起的鲤鱼开放性鳃病,但50~75 mg吡喹酮/kg饲料可以在5d内治疗该病.     

Small-Scale Shrimp Grower–Collector Relationships: The Case of Thua Thien Hue Province,Central Vietnam

Small-scale shrimp-culture is an important livelihood for rural residents in Thua Thien Hue (TTH) province, central Vietnam. However, they are facing the risk of exclusion from the food system due to globalization and trade liberalization. To keep these farmers in modern supply chains, their relationships with other chain actors, foremost the collectors, need to be improved. Thus, this study explores the characteristics and constructs of the relationships between the small-scale shrimp growers and their collectors. Data was based on a survey on 83 small-scale shrimp growers, together with 16 unstructured interviews with growers (10) and collectors (6). It was revealed that the relationships between small-scale shrimp growers and collectors in TTH province are short-term and price-driven and are influenced by the power of collectors. The relationship strength was measured by five intercorrelated constructs including reliability, willingness-to-maintain, desire-fulfilment, negotiation capacity, and discussion capacity. Although some constructs were positively correlated, the strength of the relationships was weak. Both business linkages and social connections affected the grower-collector relationships. Female traders had stronger relationships with collectors than males. Therefore, interventions should be focused on business and social linkages as well as females’ involvement in shrimp trade.     

越南不同龙眼品种品质分析比较(英文)

[目的]筛选出适合越南当地生产的龙眼品种。[方法]分别对引种至越南农科院北部山区农林研究所内栽培的5个龙眼品种的果实植物学性状和品种果实性状进行了比较分析。[结果]筛选出了可作为鲜食的优良龙眼品种PMP6,PHS1-1以及可用于加工的优良品种HuongChi。[结论]本研究将对越南北部山区的龙眼生产、育种提供参考。     

Influence of single-nucleotide polymorphisms in the gene encoding granule-bound starch synthase I on amylose content in Vietnamese rice cultivars

Amylose content is one of the most important factors influencing the physical and chemical properties of starch in rice. Analysis of 352 Vietnamese rice cultivars revealed a wide range of variation in apparent amylose content and the expression level of granule-bound starch synthase. On the basis of single-nucleotide polymorphisms (SNP) at the splicing donor site of the first intron and in the coding region of the granule-bound starch synthase I gene, Waxy gene, alleles can be classified into seven groups that reflect differences in apparent amylose content. The very low and low apparent amylose content levels were tightly associated with a G to T in the first intron whereas intermediate and high amylose was associated with a T genotype at SNP in exon 10. The correlation between the combination of T genotype at SNP in the first intron, C in exon 6, or C in exon 10 was predominant among low amylose rice varieties. Our analysis confirmed the existence of Wx^op allele in Vietnamese rice germplasm. The results of this study suggest that the low amylose properties of Vietnamese local rice germplasm are attributable to spontaneous mutations at exons, and not at the splicing donor site.     

Study on Effects of Different Medium Compositions on Growth and Seedling Quality of Two Tomato Varieties Under Greenhouse Conditions

This research was conducted to investigate the effects of different medium compositions on physicochemical properties and the growth of two tomato varieties. Five treatments were applied, combining medium composition with rice husk ash (RHS) and coconut fiber (CF) with the following proportions: 1/3 Peat moss + 1/3 rice husk ash + 1/3 coconut fiber (T1); 1/3 Vermicompost + 1/3 rice husk ash + 1/3 coconut fiber (T2); 1/3 Cattle manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T3); 1/3 Chicken manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T4); 1/3 Hog manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T5). The results demonstrated that between pH, electrical conductivity (EC) value, and nutrient content in the media, there was a significant difference that led to different concentrations of total macro- and micronutrients in the shoots of both varieties. In addition, the root weight, shoot weight, and root volume were affected by medium composition for two varieties in seedling stage. A mixture of cattle manures composted with RHS and CF under the rate (1:1:1 by volume), respectively, gave the highest value of germination rate, plant height, leaf number, and plant biomass. Medium composition significantly influenced the germination rate and elongation of seedlings, specifically for each tomato variety. Therefore, cattle manure compost as a medium supplement improves seedling quality and growth of the two tomato varieties.     

Evaluation of ground grain versus pre- and post-pellet whole grain additions to poultry diets via a response surface design

1. The objective of this study was to compare the effects of pre- and post-pellet whole grain wheat additions to diets on growth performance, gizzard and pancreas development, nutrient utilisation and starch and protein (N) digestibility coefficients in broiler chickens via an equilateral triangle response surface design.

2. The three apical treatments of the equilateral triangle comprised (1A) a standard diet containing 600 g/kg ground wheat, (2B) the same diet containing 600 g/kg pre-pellet whole wheat and (3C) the same diet containing 300 g/kg ground wheat and 300 g/kg post-pellet whole wheat. Seven blends of the three apical diets were located within the triangle to complete the design and a total of 360 male Ross 308 chicks were offered the ten experimental diets from 7 to 28 d post-hatch. Model prediction and response surface plots were generated with R 3.0.3 software.

3. The most efficient FCR of 1.466 was observed in birds offered an almost equal mixture of the pre- and post-pellet whole grain apical dietary treatments, which corresponded to 172 g/kg ground grain, 256 g/kg pre-pellet whole grain, 172 g/kg post-pellet whole grain in a diet containing 600 g/kg wheat.

4. The most efficient energy utilisation (ME:GE ratio of 0.766) was observed in birds offered a blend of the ground grain and pre-pellet whole grain apical dietary treatments which corresponded to a mixture of 384 g/kg pre-pellet whole grain and 216 g/kg ground grain.

5. Pre-pellet whole grain feeding generated the most pronounced responses in increased relative gizzard contents, reduced gizzard pH and increased relative pancreas weights. Consideration is given to the likely differences between pre- and post-pellet whole grain feeding.     

Aporphine alkaloids,clerodane diterpenes,and other constituents from Tinospora cordifolia

Phytochemical investigation of the methanol extract of Tinospora cordifolia aerial parts led to the isolation of four new and seven known compounds. The structures of two new aporphine alkaloids, N-formylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside A, 1) and N-acetylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside B, 2), a new clerodane diterpene, tinoscorside C (3), and a new phenylpropanoid, sinapyl 4-O-β-d-apiofuranosyl-(1 → 6)-O-β-d-glucopyranoside (tinoscorside D, 6) were determined by extensive spectroscopic methods including FTICR-MS and 1D and 2D NMR.     

Development of a co-dominant SCAR marker linked to the Ph-3 gene for Phytophthora infestans resistance in tomato (Solanum lycopersicum)

Random amplified polymorphism DNA (RAPD) and bulk segregant analysis (BSA) approaches were used to characterize the molecular marker linked to the Phytophthora infestans resistance gene Ph-3 in tomato. A total of 800 RAPD primers were screened. One RAPD marker UBC#602 was identified to be tightly linked to the Ph-3 gene. The marker was successfully converted into a co-dominant sequence characterized amplified region (SCAR) marker. The SCAR marker SCU602 was used to analyze 96 F₂ progenies and fitted the expected 1:2:1 Mendelian segregation ratio. Forty one tomato inbred lines were screened using the SCAR marker in comparison with a reference marker linked to the Ph-3 gene and both markers gave the same results. SCU602 was further validated for association to resistance and its potential in MAS in 72 tomato lines and cultivars. The marker identified three genotypes harbouring the resistance allele. This SCAR marker can be used in breeding programs for the selection of the Ph-3 gene for Phytophthora infestans resistance.     

Epidemiological survey for Brucella in wildlife and stray dogs, a cat and rodents captured on farms

Brucella infections in wildlife originate either from contact with infected livestock or from a natural sustainable reservoir in wildlife populations. As South Korea has set a goal of brucellosis eradication by 2013, it is necessary to determine the prevalence of Brucella in wildlife and wild rodents. This information will play an important role in the control of brucellosis. Because of the absence of prominent clinical signs, direct and indirect laboratory tests are essential for diagnosing brucellosis. In this study, tissue and blood samples were taken from wild animals, abandoned dogs, a cat and wild rodents, and they were tested for Brucella or Brucella-specific antibodies by isolation, PCR and serology. Results showed that 18.6% (33/177) of blood samples were positive by PCR, and 5.7% (11/194) were positive by C-ELISA. However, none of these samples yielded culturable bacteria. Of the tissue samples, 9.7% (8/82) were positive by PCR. Brucella was isolated from only one tissue culture from a Chinese water deer carcass. This Brucella species was identified as Brucella abortus biovar 1 by biotyping, 16S rRNA PCR and the Bruce-ladder PCR assay. In this study, we reported the prevalence of Brucella in wildlife, dogs, a cat and rodents by using serological and molecular methods, and we report the first isolation of B. abortus in wild Chinese water deer in South Korea.     

Understanding utilitarian and hedonic values determining the demand for rhino horn in Vietnam

We examined utilitarian and hedonic values as motivations for rhino horn use in Vietnam. We also evaluated consumers’ response to consequences of the illegal trade in behavior modification campaigns and the likely outcome of a legalized trade. The most prevalent use was for treatment of hangovers indicating utilitarian values, although difficult to separate from the hedonic value in projecting success in business. A ritualized way of honoring terminally ill relatives represented a hedonic value replacing belief in effective treatment. Demand reduction campaigns need to appropriately reflect all relevant values determining specific uses. The plight of rhino populations, Vietnam’s penal code, and the possible contribution to international crime mattered little to consumers. Horn from wild rhino was preferred over farmed, and respondents would demand more if available in a legalized trade. This suggested that a legalized trade could maintain or even increase demand for poached rhino horn.