Beneficial effects on meat quality of yellowtail Seriola quinqueradiata induced by diets containing red pepper

The meat quality of farmed yellowtail Seriola quinqueradiata fed on extruded pellets (EP) containing 0.5% (v/v) red pepper (experimental group) was compared with yellowtail of the same age fed on EP (control group). In 1-year-old yellowtail, the crude lipid content of the dorsal muscle of the experimental group tended to be lower than that of the control group. In contrast, there was no difference in the lipid content of the dorsal muscle between the control group and the experimental group in 2-year-old yellowtail. The muscle texture of the experimental group was significantly firmer than that of the control group, with the effect of red pepper unrelated to fish age and lipid content. Color change of red muscle of the experimental group was significantly lower than that of the control group, and the content of thiobarbituric acid-reactive substances in the red muscle was significantly lower in the experimental group than in the control group. These results are the first to demonstrate that the inclusion of red pepper in the diet is able to reduce the loss of muscle texture firmness and to slow down color change in red muscle of yellowtail.     

Improvement of diagnostic markers for resistance to Globodera pallida and application for selection of resistant germplasms in potato breeding

Occurrence of pale potato cyst nematode, Globodera pallida (Stone) Behrens, was first recorded in Japan in 2015. Among several control measures, cultivation of resistant potato (Solanum tuberosum L.) varieties is the most effective in cost and environmental impact. As no G. pallida-resistant varieties have yet been developed in Japan, great emphasis is being placed on screening of germplasm possessing the resistance and development of the resistant varieties. In this study, we first improved previously reported DNA markers linked to the G. pallida resistance loci (GpaIV^s_adg and Gpa5) and then used these to screen more than 1,000 germplasms to select several candidate germplasms with resistance. We performed inoculation testing on the selected candidates and identified several resistant germplasms to the Japanese G. pallida population. Furthermore, we developed a simultaneous detection method combining three DNA markers linked to G. pallida and Globodera rostochiensis (Wollenweber) Behrens resistance loci. We validated the ability of C237-I marker to select resistant allele of GpaIV^s_adg and predict the presence of resistance in a Japanese breeding population. Resistant germplasms identified in this study could potentially be used to develop G. pallida-resistant varieties. The marker evaluation methods developed in this study will contribute to the efficient development of resistant varieties.     

Potential of near infrared spectroscopy to determine the lipid content of untreated garbage compost

The purpose of the present study was to evaluate the capability of near infrared spectroscopy (NIRS) as a simple method to monitor the lipid content of garbage compost, which is a potential inhibitor of plant growth. We conducted a cultivation experiment with vegetable mock pak choy ( Brassica rapa L. Parachinensis Group) using two application rates of four garbage composts that differed in lipid content. The input of lipid from the compost to the field showed a significant negative correlation with germination rate and plant height in the initial growth stage. Reflectance spectra of untreated and freeze-dried and milled compost samples were taken using a scanning monochromator. Second-derivative spectra and multiple regression analysis were used to develop calibration equations for lipid and moisture contents. The calibration was carried out with the short wavelength region ([SWR] 800–1100 nm) and the long wavelength region ([LWR] 1100–2500 nm) separately. The calibration equations with the LWR were more accurate than those with the SWR for lipid and moisture determinations. The accuracies of the calibration equations for untreated samples were comparable to those for freeze-dried and milled samples. In conclusion, we suggest that the application rate of garbage compost can be determined by measuring the lipid content of untreated samples by NIRS.     

Starch Damage and Pasting Properties of Rice Flours Produced by Dry Jet Grinding

Milling method and particle size affect some properties of rice flour. To prepare ultra‐fine rice flour of <30 μm, hammer and dry jet grinding methods were examined and the effect of particle size on starch damage and pasting properties of the flour were elucidated. A jet mill could make finer flour (<10 μm mean size) with a narrower particle size distribution than a hammer mill could. Starch damage increased dramatically at a mean size of <10 μm. Particles of a similar size (<60 μm) had different levels of starch damage between mills. Not only the particle size, but also the milling method affected the level of damaged starch. Flour samples of ≥45 μm mean size had similar viscosity curves, but samples of <20 μm had different curves. Peak viscosity and final viscosity decreased sharply at <10 μm. Setback viscosity for particles of 3 μm from both brown rice and white rice were higher than the peak viscosity. Stability to heat and shearing stress were decreased for <20 μm flours as the breakdown viscosities decreased. Starch damage and pasting properties of flour ground from the nonwaxy japonica cultivar Koshihikari changed dramatically at a mean size of <10 μm.     

Effects of carbamate, BPMC, on the central cholinergic functions and behavior of mice

O-sec-butylphenyl methylcarbamate (BPMC), an anticholinesterase carbamate, was injected once (100 mg/kg, s.c.) or repeatedly (50 mg/kg/day for 10 days) into mice. Animals were examined for their behavior and for parameters of cholinergic activity in the forebrain. Mice that received only a single injection exhibited reduced ambulation, hypothermia, and impairment of rotarod performance for up to 3 hr after a single injection. BPMC increased levels of acetylcholine (ACh) in the forebrain for up to 6 hr, and decreased acetylcholinesterase (AChE) activity for up to 24 hr. Both high-affinity choline uptake (HACU) and binding of [3H]quinuclidinyl benzilate (QNB) were reduced 20 min after a single injection without any effect on choline acetyltransferase (ChAT) activity. In behavioral tests conducted 10 min prior to the daily injections, rotarod performance and ambulation were slightly impaired for a few days before and after cessation of injection. Repeated treatment decreased HACU and binding of [3H]QNB for 24 hr after the final injection without any changes in levels of ACh content, AChE activity and ChAT activity. BPMC may reversibly impair cholinergic functions through effects not only on AChE activity but also on HACU and binding of [3H]QNB.     

Characterization of new monoclonal antibodies against porcine lymphocytes: molecular characterization of clone 7G3, an antibody reactive with the constant region of the T-cell receptor delta-chains

A battery of mouse monoclonal antibodies (mAbs) reactive with porcine peripheral blood (PB) leukocytes was generated. Among the mAbs, 6F10 was found to react probably with cluster of differentiation (CD)8 alpha-chain, while 7G3 and 3E12 were found to recognize gammadelta T-cells, as revealed by two-color flow cytometric and immunoprecipitation studies. 7G3 was shown to react with the constant (C) region of the T-cell receptor (TCR) delta-chain by the following facts: (1) 7G3 immunoprecipitated full-length TCR delta-chain protein fused with glutathione S-transferase (GST) produced by Esherichia coli and (2) 7G3 reacted with TCR delta-chain expressing Cos-7 cells transfected with either full-length or N-terminal deleted mutant cDNA, but did not react with Cos-7 cells transfected with C-terminal deleted mutant TCR delta-chain cDNA. All three mAbs produced high-quality immunostaining results on frozen sections, revealing a distinct distribution of gammadelta T-cells and CD8(+) cells. This report precisely characterizes mAbs against porcine TCR for the first time, facilitating molecular biological investigations of the porcine immune system.     

Successive changes of hematologic characteristics and plasma chemistry values of juvenile loggerhead turtles (Caretta caretta).

Hematologic characteristics and plasma chemistry values of juvenile loggerhead turtles (Caretta caretta) from the ages of 1 mo to 3 yr were obtained to establish baseline values. Five clinically normal loggerhead turtles were selected from the same clutch and raised in an indoor artificial nesting beach. Blood samples were successively collected and examined for various blood characteristics for a maximum total of 15 times. Hematologic characteristics, including packed cell volume, white blood cell counts, and white blood cell differentials; and plasma chemistry values, including total bilirubin, total protein, albumin, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, gamma-glutamic transpeptidase, creatinine, blood urea nitrogen, uric acid, alkaline phosphatase, amylase, triglyceride, total cholesterol, ionized sodium, ionized potassium and ionized chlorine, were measured. These results were used to establish a hematology and blood chemistry baseline for captive juvenile loggerhead turtles and will aid in their medical management.     

Brachyspira pilosicoli isolated from two beagles and one mongrel in Japan

The feces, colonic contents, and colonic mucosa from two beagles and a mongrel with and without mucohemorrhagic diarrhea were anaerobically cultured and after 72 hr, lucent and rough colonies with weak beta-hemolysis were observed. Small spirochetes with one or two loose waves in the colonies were observed under a phase contrast microscope and the spirochete cells sometimes aggregated. The 16SrDNA sequencing results demonstrated that the canine isolates were B. pilosicoli and the base alignments registered in DDBJ. This is the first report concerning the isolation of B. pilosicoli from dogs in Japan.     

Photosynthesis of the rice plant under water stress

Leaf-resistance values sharply decreased after sunrise, remained low during daytime, and increased sharply toward sunset. This general pattern was modified by weather conditions and soil-water stress. On a cloudy day, leaf resistance remained low (3-5 s/cm) during daytime regardless of the soil-water regime. No increase in leaf resistance equivalent to “midday closure of stomates” was observed under flooded conditions on a sunny day. Under water stress and on a sunny day, leaf resistance began to increase in the morning or afternoon, depending on the degree of water stress. Both the light intensity at which the leaf photosyn-thetic rate reached light-saturation and the maximum value of the photosynthetic rate became lower as water stress became more severe. A simulation model revealed that crop photosynthesis was almost identical (17-18 g·m^-2·day^-l) for both water-stressed and well-watered crops on a cloudy day when solar radiation was 200 cal·cm^-2day^-l. On a sunny day, when solar radiation was 600 cal·cm^-2day^-l, however, crop photosynthesis under water stress reached its maximum at about 8 a.m., after which it declined with time and became almost zero after 12 noon. Under flooded conditions, diurnal changes in crop photosynthesis were similar to those of incident solar radiation. As a result, crop photosynthesis was about 33 g·cm^-2day^-l under flooded conditions and only about 10 g·cm^-2day^-l under water stress. Thus, crop photosynthesis under water stress was greater by 70% on a cloudy day than on a sunny day. This suggests that a partly shaded environment favors crop growth under water stress.     

Distribution of radioactive cesium in edible parts of cattle

After the disastrous incident of the Fukushima Daiichi Nuclear Power Station, various agricultural, livestock and fishery products have been inspected for radioactive contamination with cesium in Japan. In this study, radioactive cesium was measured in various edible parts of cattle to verify the current inspection method for cattle, in which the neck tissues are generally used as samples. Radioactive cesium concentration in the short plate, diaphragm, liver, lung, omasum, abomasum and small intestine were lower and sirloin, tenderloin, top round meat and tongue were higher than that in the neck. There was no significant difference between the other organs (heart, kidney, lumen and reticulum) and the neck. Ninety‐five percent upper tolerance limits of the relative concentration to the neck were 1.88 for sirloin, 1.74 for tenderloin, 1.87 for top round and 1.45 for tongue. These results suggest that a safety factor of 2 is recommended for the radioactivity inspection of cattle to prevent a marketing of meat with higher cesium than the legal limit. Re‐inspection should be conducted using another part of muscle, for example, top round, when suspicious levels of 50–100 Bq/kg are detected in the neck.