Optimum Dietary Protein Level and Protein‐to‐energy Ratio for Growth of Juvenile Parrot Fish,Oplegnathus fasciatus

An 8‐wk feeding trial was conducted to estimate the optimum dietary protein level and protein‐to‐energy (P/E) ratio in juvenile parrot fish, Oplegnathus fasciatus. Eight experimental diets were formulated with two energy levels and four protein levels for each energy level. Diets containing crude protein (CP) at 35, 40, 45, and 50% had either 12.5 or 14.6 kJ/g of energy. Fish averaging 7.1 ± 0.06 g (mean ± SD) were fed one of the experimental diets for 8 wk. At the end of the feeding trial, weight gain (WG) of fish fed 45 and 50% CP in the 12.5 kJ/g diet was significantly higher than fish fed the 35% CP diet (P < 0.05). WG of the fish fed 45 and 50% CP in the 14.6 kJ/g diet was significantly higher than fish fed the 35 and 40% CP diets (P < 0.05). Fish fed the 14.6 kJ/g diet had a higher WG compared with fish fed the 12.5 kJ/g diet at all CP levels. Feed efficiency (FE) and specific growth rate (SGR) showed a similar trend to the WG. WG, FE, and SGR improved with increasing dietary protein levels up to 45% and remained constant at 50% CP for both energy levels. However, protein efficiency ratio was negatively related to dietary protein levels. The results suggested that the optimum level of protein and the optimum P/E ratio for juvenile parrot fish should be 45% and 31.1 mg protein/kJ, respectively, in a diet containing 14.6 kJ/g energy.     

A survey of porcine reproductive and respiratory syndrome among wild boar populations in Korea

No information is currently available on porcine reproductive and respiratory syndrome virus (PRRSV) infection in wild boars (Sus scrofa) in Korea. In this study, the status of PRRS in wild boars was investigated. Blood samples were collected from 267 wild boars from eight provinces in Korea. Four of the samples tested (1.5%) were positive for PRRSV antibodies and eight (3.0%) were positive for antigens. Of the virus-positive samples, three and five samples were typed as containing European (EU, type 1) or North American (NA, type 2) viruses, respectively. Two amplicons (one from type 1 and one from type 2) were used to analyze the PRRSV open reading frame 7 (ORF7) sequence. The nucleotide sequences of type 1 PRRSV ORF7 had identities between 96.1% and 98.4% with PRRSVs from domestic pigs in Korea. The sequences of type 2 PRRSV ORF7 had identities of 100% with the PRRSV strain VR-2332, which was prototypic North American strain. These results show that PRRSVs are present in wild boars in Korea, and effective PRRSV surveillance of the wild boar population might therefore be useful for disease control.     

Visible light induced dextran-methacrylate hydrogel formation using (−)-riboflavin vitamin B2 as a photoinitiator and L-arginine as a co-initiator

The objective of this study is to examine the feasibility of using visible light to form gels from polysaccharide precursors. Hydrogel formation by visible light irradiation would be very beneficial because visible light is a benign light source and ready available when compared with other light sources such as UV. Dextran-methacylate was synthesized and photocrosslinked using (−)-riboflavin as a photoinitiator and L-arginine as a co-initiator under the visible light. The effect of various concentrations of (−)-riboflavin and L-arginine on the photo-crosslinking of dextran-methacrylate hydrogel was investigated. The fabricated hydrogel was characterized by FT-IR and SEM. The photoinitiator [(−)-riboflavin] and co-initiator (L-arginine) as well as dextran precursor are completely biocompatible. The optimum condition for the biocompatible dextran-based hydrogel formation under the harmless light source (visible light) was elucidated in this study. In general, the (−)-riboflavin, 0.01–0.5 %, and L-arginine, 5–20 % of the weight of dextran-methacrylate were the best condition in forming dextran-based hydrogels under the visible light. The three-dimensional hydrogel structure was verified by SEM morphology of swollen hydrogels. Photocrosslinking under the visible light source would enlarge the applications of this type of photocrosslinking in the biomedical area (e.g., eyes or other light-sensitive organs).     

Preliminary Study of the Optimum Dietary Riboflavin Level in Sea Cucumber,Apostichopus japonicus (Selenka)

A 14‐wk feeding trial was carried out to evaluate the optimum dietary riboflavin (vitamin B₂) level in juvenile sea cucumber, Apostichopus japonicus. A total of 360 sea cucumbers averaging 1.49 ± 0.07 g (mean ± SD) were randomly distributed into 18 rectangular plastic tanks, and each tank was then randomly assigned to one of three replicates of six diets containing 0.29 (B₂0), 4.22 (B₂4), 8.93 (B₂9), 17.9 (B₂18), 56.7 (B₂57), and 577 (B₂577) mg riboflavin/kg diet. At the end of 14 wk of feeding trial, average weight gain (WG) of sea cucumbers fed B₂9, B₂18, B₂57, and B₂577 diets were significantly (P < 0.05) higher than that of animals fed B₂0 diet. WG of sea cucumbers fed B₂18, B₂57, and B₂577 diets were significantly higher than those of animals fed B₂0 and B₂4 diets. Specific growth rate of sea cucumbers fed B₂9, B₂18, B₂57, and B₂577 diets were significantly higher than those of animals fed B₂0 and B₂4 diets. Feed efficiency of sea cucumbers fed B₂9, B₂57, and B₂577 diets were significantly higher than those of animals fed B₂0 and B₂4 diets. Although significant differences were recorded in proximate composition of sea cucumbers fed the experimental diets, no clear trends were observed. The ANOVA test suggested that the optimum dietary riboflavin level in sea cucumber could be 17.9 mg/kg diet but broken‐line analysis of WG indicated a level of 9.73 mg riboflavin/kg diet. Therefore, these results may indicate that the optimum dietary riboflavin level in sea cucumber could be higher than 9.73 mg/kg diet but lower than 17.9 mg/kg diet.     

栗疫病菌弱毒性菌株的筛选及其dsRNA的转化稳定性

为获取栗疫病生物防治的基础信息,本研究根据菌株在PDA培养基上培养7天后的菌丝生长速度、分生孢子形成能力等培养特性,从韩国国立山林科学院树木病理研究室保藏的60个栗疫病菌菌株中筛选了2个弱致病力菌株,进行dsRNA检测、弱致病力菌株和强致病力菌株间的细胞融合试验。结果表明:2个弱致病力菌株(KCP-135和KCP-136)中均检测到了dsRNA,弱毒性菌株KCP-22和其他19个强毒性菌株之间的菌落形成明显的隔离带并沿着隔离带产生分生孢子,没有明显的细胞融合现象,而弱毒性菌株KCP-22和强毒性菌株KCP-9之间的菌落则呈现了显著的细胞融合现象,而且其细胞融合菌株的培养特性和转化dsRNA数量均发生了变异。     

Acute interstitial pneumonia in feedlot cattle: effects of feeding feather meal or vitamin E.

We evaluated the effects of feeding 1.5% cysteine-rich feather meal or 550 IU of vitamin E for 40 d before slaughter on the rates of death and emergency slaughter due to acute interstitial pneumonia (AIP) in commercial feedlots. Blood and lung tissue were collected at slaughter from 83 animals clinically diagnosed with AIP, 40 asymptomatic penmates, and 40 heifers receiving either feather meal (20) or vitamin E (20); the left lung was subsampled for histologic examination. Blood and lung tissue were analyzed for thiol adducts of 3-methyleneindolenine (3ME) and reduced glutathione. Supplementation with feather meal or vitamin E had no effect on the rates of death and emergency slaughter attributable to AIP and did not influence the levels of 3ME or reduced glutathione in blood or lung tissue. Although supplementation with greater amounts of feather meal or vitamin E may have been necessary to significantly affect factors related to feedlot AIP, increased supplementation would be uneconomical for commercial feedlots, given the relatively low incidence of AIP.     

Synthesis and spectral properties of phthalimide based alkali-clearable azo disperse dyes

The synthesis of a series of phthalimide based azo disperse dyes and their spectral properties were investigated. The azo dyes containing phthalimide and N-methyl phthalimide structure in diazo component were synthesized in order to compare their spectral properties. The synthesized dyes developed the color of yellow to violet and the N-substitution of the phthalimide gave a bathochromic effect on the color change. Most of the synthesized dyes exhibit negative solvatochromism so that the absorption band of dyes moves toward shorter wavelengths as the polarity of the solvent increases. In the case of halochromic effect, the bathochromic shift decreased steadily with the general electron donating capacity of the substituents in the coupling component, and became negative especially when more powerful electron donating groups are present in the coupling components ring.     

Protective effects of bio-active ceramic water on alcohol-induced hepatic injury in pigs

Among many detrimental injuries, alcohol is implicated in hepatitis, fatty liver, hepatic fibrosis, and cirrhosis. The purpose of this study was to evaluate the protective effect of bio-active ceramic water on alcohol-induced hepatic injury in pigs. Twelve male Landrace pigs were divided into 3 groups. Groups 1, 2, and 3 were fed with bio-active ceramic water + normal liquid diet, bio-active ceramic water + liquid diet containing 15% ethanol, and tap water + liquid diet containing 15% ethanol for 12 weeks, respectively. For serological, histopathological, and immunohistochemical analysis, all pigs were sacrificed at week 12. In group 3, serum ALT and AST levels increased, and mild fatty change and moderate necrosis were detected in the liver. Collagen fibers, myofibroblasts, and CYP2E1 were also increased or activated in group 3. In group 2, there were mild hepatic injuries compared to group 3. However, injuries and activations were not observed in the liver in group 1. We suggest that the bio-active ceramic water used in the present study had protective capability against ethanol-induced hepatic injury and that having no toxic effect on the pig liver. The bio-active ceramic water might be useful as a therapeutic drinking water in patients suffering from alcoholic liver diseases.