Development of two alternative Loop‐mediated isothermal amplification tools for detecting pathogenic pine wood nematodes

Loop‐mediated isothermal amplification (LAMP) detection tools have great potential for diagnosing the causal agents of infectious diseases in clinics and in agriculture. In this work, we developed two alternative LAMP protocols for detecting the pathogenic nematode Bursaphelenchus xylophilus, causal agent of pine wilt disease. We first identified a pectate lyase 3 gene as a biomarker for developing a LAMP Detection Kit, as there was no homologue in non‐pathogenic nematodes that live in pine timber or bark and show structural similarities to B. xylophilus. The first LAMP protocol used the Genie II equipment and an isothermal master mix containing Geobacillus sp. M 2.0 large fragment DNA polymerase showed approximately 10 times greater sensitivity with a shorter incubation period compared with that of the second LAMP protocol, which utilized a fluorescence metal indicator, calcein and an engineered Bacillus stearothermophilus DNA polymerase I, large fragment (Bst 2.0 DNA polymerase). However, the LAMP reactions with calcein and Bst 2.0 polymerase were the cost‐effective method because the reaction could be performed using a simple isothermal block and relatively inexpensive calcein as a fluorescence indicator visible to the naked eye.     

Relationship between endogenous protein disulfide isomerase family proteins and glutenin macropolymer

The effects of endogenous protein disulfide isomerase (PDI) family proteins on the properties of gluten proteins in dough during breadmaking were determined using bacitracin, an inhibitor of PDI. Bread loaf volume in the presence of bacitracin was increased to 118% of that in the absence of bacitracin. The addition of bacitracin caused a decrease in the extension tolerance of the dough. The amount of sodium dodecyl sulfate (SDS)-insoluble glutenin macropolymer (GMP) in dough decreased to approximately 70% of that in flour during the 20 min of mixing for doughmaking. The addition of bacitracin to dough caused a dramatic GMP decrease, corresponding to ～20-30% of that in flour during the 20 min of mixing. The decrease in GMP was compensated by an increase in SDS-soluble glutenin polymer. Taken together, these results suggest that the endogenous PDI family proteins in flour suppress the depolymerization of GMP during dough mixing.     

籼稻品种味度及淀粉RVA谱特性配合力分析

选用8个籼稻品种,采用Griffing双列杂交方法Ⅳ,对稻米味度及淀粉黏滞性谱（RVA谱）特性配合力进行分析。结果表明,(1) 在稻米味度、最高黏度、最低黏度、最终黏度、下降黏度值、黏滞峰消减值、回冷黏滞性恢复值等特性中,亲本基因的加性效应对杂种一代起主导作用,而糊化开始温度的遗传变异主要来自基因的非加性效应;(2)     

Toxicity of spray and fumigant products containing cassia oil to Dermatophagoides farinae and Dermatophagoides pteronyssinus (Acari: Pyroglyphidae)

The toxicity of formulations of oil of cassia, Cinnamomum cassia Blume, (20 and 50 g L(-1) sprays and 100% oil-based fumigant) to adult Dermatophagoides farinae Hughes and D. pteronyssinus Trouessart was examined using contact and vapour-phase toxicity bioassays. Results were compared with the lethal activity of three commercial acaricides: benzyl benzoate, dibutyl phthalate and diethyl-m-toluamide (deet). The contact toxicity of cassia oil to both dust mite species was comparable with that of benzyl benzoate but was higher than that of the other two acaricides. Sprays containing 20 and 50 g L(-1) cassia oil were effective against both mite species when applied to fabric, glass, paper, plastic, tin or wood substrates. Applications of the 50 g L(-1) spray to different space volumes and surface areas determined that 50-60 mg of cassia oil was needed to control dust mites in 3.4 m(3) or in 1 m(2). In tests with fumigant devices, toxicity varied according to the thickness of non-woven fabric covering the device, the exposure time, the number of fumigant devices used and the volume of the space sprayed. Fumigant toxicity to adult D. pteronyssinus was more pronounced with devices enclosed in thinner (40 microm) versus thicker (45 or 50 microm) non-woven fabric covers. A single fumigant device with a 40 microm thick non-woven fabric cover resulted in substantial control in a space of 0.05 m(3) but exhibited only moderate to weak control in spaces >or= 0.097 m(3) at 4 days after application. Two fumigant devices gave 88% mortality in a space of 1.73 m(3). Cassia oil applied as sprays or in fumigant devices appears to provide effective protection of humans from house dust mites.     

Improvement in the in vitro Digestibility of Shrimp Meal by the Addition of Persimmon Peel

The present study was conducted to analyze the chemical properties of persimmon peel (PP) and the in vitro digestibility of shrimp meal (SM) diets containing PP. Discussions whether PP can be used as a feed additive to promote digestion of SM in chickens are also included. The chemical composition and chitinase activity of dried PP was studied. SM diets containing PP were formulated according to the 4 by 6 factorial design: 4 levels of SM (0%, 10%, 15%, and 20%) × 6 levels of PP (0%, 2%, 4%, 6%, 8%, and 10%). The in vitro digestibility of dry matter (IVDMD), crude protein (IVCPD), and chitin (IVCD) was also studied. PP was rich in nitrogen-free extract (NFE, about 74%) and tannin (2.8%), and the highest chitinase activity of PP was observed at pH 4.5. Approximately 50% of chitinase activity was also observed at acidic (3.0) and alkaline (8.0) pH. Its activity was slightly affected by pepsin treatment. IVDMD increased upon addition of up to 8% PP, but decreased with an increase in the level of SM. When PP level was increased up to 6%, IVCPD in the group containing 0% SM, changed slightly; however, an increasing trend was observed in the other groups. When PP level was more than 6%, IVCPD decreased in all the groups. IVCD increased dose-dependently with increasing level of PP and decreased with increasing level of SM. In conclusion, PP was rich in NFE, had high chitinase activity, and improved all digestibility parameters, such as IVDMD, IVCPD, and IVCD, in SM diets where the PP level was under 6%. Thus, up to 6% of PP can be safely included in SM diets as a digestion promoter.     

Biotransformation of an organochlorine insecticide,endosulfan, by Anabaena species

This study assesses the role of the blue-green algal species present in the soil in the dissipation of endosulfan and its metabolites in the soil environment. Two Anabaena species, Anabaena sp. PCC 7120 and Anabaena flos-aquae, were used in this study. Anabaena sp. PCC 7120 produced three principal biotransformation compounds, chiefly endosulfan diol (endodiol), and minor amounts of endosulfan hydroxyether and endosulfan lactone. Trace amounts of endosulfan sulfate were detected. In comparison, the biotransformation of endosulfan by Anabaena flos-aquae yielded mainly endodiol with minor amounts of endosulfan sulfate. An unknown compound was produced up to 70% from endosulfan spiked in the medium inoculated by A. flos-aquae after 8 days of incubation. Therefore, the endosulfan fate was dependent on the species. Within 1 day of incubation, two Anabaena species produced low amounts of beta-endosulfan after application of alpha-endosulfan. These results suggest the presence of isomerase in the Anabaena species. Further studies using a fermentor to control the medium pH at 7.2 to minimize chemical hydrolysis of endosulfan revealed a major production of endodiol with minor amounts of endosulfan sulfate and the unknown compound. These results showed that the production of the unknown compound might be dependent on the alkaline pH in the medium and that the production of endodiol by A. flos-aquae might be biologically controlled. This study showed that two algal species could contribute in the detoxification pathways of endosulfan in the soil environment.     

Intestinal morphology and enteral nutrient absorption of pigeon pea seed meal in piglets

This study was conducted to establish the relationship between histological alterations of the intestinal villus and intestinal function, and to histologically assess the enteral nutrient absorption of raw pigeon pea seed meal (PM). Piglets were allotted into five groups: feed withdrawal for 3 days or 5 days, refeeding soybean meal (SM) or PM for 2 days after the 3‐day fast, and access ad libitum to conventional feed for the last 2 days without fasting. After the end of each experiment, the intestinal segment and duodenum of each piglet were processed and examined by light and scanning electron microscopy, respectively. After fasting, villus height, cell area and cell mitosis number were decreased in most parts of each intestinal segment, and duodenal villus tips had a smooth surface. After refeeding SM or PM, the decrease in body weight improved, but there was not a significant difference between them. The atrophic morphology of the intestine was reversed by refeeding SM, suggesting that the intestinal villi might be activated by absorption of SM. On the other hand, in the piglets refed PM, the recovery of light microscopic parameters and duodenal villus tip morphology was less clear than with SM. The present histological results suggest that although the absorption of PM is less than that of SM, the PM nutrients might be effectively absorbed, even in the raw form, and establish that in pigs intestinal histological alterations correspond well with intestinal absorptive function.     

Growth traits and composition of two- and three-way-cross intact male progeny of Bos taurus and Bos indicus X Bos taurus dams

Feedlot traits, carcass traits and distribution of commercial cuts of crossbred intact male progeny (n = 556) from young and mature Hereford, Red Poll, Hereford X Red Poll, Red Poll X Hereford, Angus X Hereford, Angus X Charolais, Brahman X Hereford and Brahman X Angus dams were evaluated. First-calf heifers were bred to Red Angus bulls; Santa Gertrudis sires were used for each cow's second and third breeding seasons. Calves from these young dams were slaughtered at 13 mo. Calves of mature dams were all sired by Limousin bulls and slaughtered at 12 mo. Dam breed was a major source of variation in most bull traits. Progeny of Brahman-cross dams were inferior (P less than .01) in daily gain, final weight, carcass weight and in edible cuts/day of age compared with progeny from Bos taurus dams. Intact male progeny of Angus X Charolais dams ranked highest in longissimus area, cutability, and edible cuts/day of age. The range of dam breed means in percentage of steak, roast, bone-in cuts (chuck short ribs and back ribs), short plate and thin cuts, and lean trim was just over 1%. Greater variation among dam breeds existed in fat measurements. Analyses in which Hereford-Red Poll diallel data for young dams and mature dams were combined showed positive maternal heterosis for dressing percentage (P less than .05), carcass weight (P less than .05), carcass weight/day of age (P less than .05), estimated carcass fat (P less than .05), fat thickness (P less than .01) and marbling score (P less than .01). Reciprocal effects were inconsequential. Results illustrate the importance of dam breed-type effects in formulating breeding strategies for commercial beef herds.