Effects of dietary protein level in the early fattening period on free amino acids and dipeptides in the blood and Longissimus thoracis muscle in Japanese Black steers

The effects of crude protein (CP) concentration in feed using soybean meal as its source in the early fattening period on the levels of free amino acids (FAAs) and dipeptides in the blood, and the levels in the M. longissimus thoracis after slaughter were studied in Japanese Black steers. Sixteen steers were divided into four groups and given feed with a CP content of 12, 14, 16, or 18% of dry matter (DM) from 10 to 20 months old, and they were fed with the same level of CP (13.5–13.9% of DM) until slaughter at 30 months of age. There was no significant difference in the weight gain, carcass weight or marbling score between the groups. Concerning the serum FAA and dipeptide contents at 20 months of age, the alanine, tyrosine and tryptophan levels decreased, while the carnosine (Car) level increased, with increases in the CP level in the feed. Although there were no significant differences in the FAA contents of the Longissimus thoracis muscle between the groups, the Car content decreased with increases in the feed protein level.     

QTL mapping of fruit nutritional and flavor components in tomato (<Emphasis Type="Italic">Solanum lycopersicum</Emphasis>) using genome-wide SSR markers and recombinant inbred lines (RILs) from an intra-specific cross

Fruit nutritional and flavor components are important targets for breeding new cultivars of tomato (Solanum lycopersicum L.). We developed 108 recombinant inbred lines (the K39 RILs) in the F₆ generation from a cross between two phenotypically different breeding lines, K03 and K09. A linkage map was constructed using 172 genome-wide simple sequence repeat markers, 3 single-nucleotide polymorphism markers, and 2 phenotypic markers. The K39 RIL map consists of 12 linkage groups (LGs) and covers a genetic distance of 1089 cM. We measured the fruit soluble solids content (SSC), titratable acidity (TA), glutamic acid content (GLU), and lycopene content (LYC) of each line in four generations (F₆, F₈, F₁₀, F₁₁), β-carotene content (CAR) in two generations, and pH in one generation. By composite interval mapping that considered yearly variations in components as non-genetic effects, we detected three quantitative trait loci (QTLs) for SSC, four for TA, two for CAR, and one each for GLU, LYC, and pH. Among them, we found two QTLs for TA in LGs 6 and 11, those for GLU and LYC were candidates for novel QTLs. QTLs detected in this study were clustered in five LGs, but we observed no apparent trade-off relationships among the QTLs in each LG. Being derived from an intra-specific cross of tomato breeding materials, these QTLs can be used in practical breeding for improving fruit quality with low risk of linkage drag.     

Impact of metritis on the generation of reactive oxygen species by circulating phagocytes and plasma lipopolysaccharide concentration in peripartum dairy cows

This study examined the relationship between postpartum metritis, reactive oxygen species (ROS) generation, and plasma lipopolysaccharide (LPS) concentration in peripartum dairy cows. Blood was collected twice weekly from 2 weeks prepartum through 6 weeks postpartum. Whole blood chemiluminescence (WBCL) was measured using the luminol‐enhanced zymosan‐stimulated chemiluminescence assay. Cows were examined for uterine health disorders and classified into two groups, healthy (n = 11) and metritis (n = 5). Metritis had a significant effect on WBCL, with cows with metritis having a higher WBCL. Plasma LPS concentrations in cows with metritis were significantly higher than in healthy cows. To examine the effect of LPS on WBCL, blood was sampled in healthy peripartum cows (1 to 2 weeks prepartum, n = 8; 0 to 3 weeks postpartum, n = 11; and 4 to 8 weeks postpartum, n = 8) and incubated with LPS. At 1 endotoxin units/mL of LPS, similar to the plasma LPS concentration in cows with metritis, the WBCL increased in cows at 0 to 3 weeks postpartum. Results indicate that the increase in ROS generation and plasma LPS concentration are associated with metritis, and LPS may be responsible for enhanced ROS generation in early postpartum dairy cows.     

Investigation of genetic diversity and inbreeding in a Japanese native horse breed for suggestions on its conservation

Because native breeds can serve as genetic resources for adapting to environment changes, their conservation is important for future agroecosystems. Using pedigree analysis, we investigated genetic diversity and inbreeding in Japanese Hokkaido native horses, which have adapted to a cold climate and roughage diet. Genetic diversity was measured as the number of founders and the effective number of founders, ancestors and genomes. All metrics imply a decrease in genetic diversity. A comparison of these metrics suggested that pedigree bottlenecks contributed more than did random gene losses to the reduction of genetic diversity. Estimates of marginal contributions of ancestors suggest that the bottlenecks arose mainly because related stallions had been used for breeding. A tendency for an increase in inbreeding coefficients was observed. F‐statistics revealed that a small effective population size majorly contributed to this increase, although non‐random mating in particular regions also contributed. Because the bottlenecks are thought to have reduced the effective population size, our results imply that mitigation of bottlenecks is important for conservation. To this end, breeding should involve genetically diverse stallions. In addition, to prevent non‐random mating observed in particular regions, efforts should be made to plan mating with consideration of kinships.     

Quality prediction of Japanese green tea using pyrolyzer coupled GC/MS based metabolic fingerprinting

A couple between pyrolyzer and gas chromatography/mass spectrometry (GC/MS) has allowed a fast, simple, and low-cost approach to evaluate a quality of Japanese green tea without any sample preparation or derivatization techniques. Using our method, errors from sample preparation could be avoided since raw samples were directly extracted through the extreme heat of the pyrolyzer. In addition, undesired reactions from expensive derivatizing agents, which are commonly needed to treat the samples before analyzing with GC/MS, could be omitted. In order to illustrate the efficiency of this technique, a set of green tea samples from the Tea contest in 2005 in the Kansai area were used. Projection to latent structure by means of partial least squares (PLS) along with orthogonal signal correction (OSC) was selected to explain the relation between green tea's metabolite profiling and its quality. The quality of the model was validated by testing and comparing the predictive ability to the respective model.     

High-throughput technique for comprehensive analysis of Japanese green tea quality assessment using ultra-performance liquid chromatography with time-of-flight mass spectrometry (UPLC/TOF MS)

Applications of metabolomics techniques along with chemometrics provide an understanding in the relationship between metabolome of green tea and its quality. A coupled of ultra-performance liquid chromatography with time-of-flight mass spectrometry (UPLC/TOF MS) allowed a high-throughput and comprehensive analysis with minimal sample preparation. Using this technique, a wide range of metabolites were investigated. Data analysis was rapid, considering that the fingerprinting technique was performed. A set of green tea samples from 2006 tea contest of the Kansai area was analyzed to prove usefulness of the developed technique. Green tea with different qualities were discriminated through principal component analysis (PCA). Consequently, projection to latent structure by means of partial least-squares (PLS) was performed to create a constructive quality-predictive model by means of metabolic fingerprinting. Beside epigallocatechin, other predominant catechins, including epigallocatechin gallate and epicatechin gallate, detected in green tea were found to be significant biomarkers to the high quality of Japanese green tea (Sencha).     

Structures and antioxidant activity of anthocyanins in many accessions of eggplant and its related species

Anthocyanins were detected in extracts from the peels of 123 accessions of eggplant (Solanum melongena) and its related species. Their anthocyanin profiles were classified into four types, including known Japanese eggplant type (type 1) and non-Japanese eggplant type (type 2). Although most of the eggplant accessions had one of the two known profiles, one accession had a novel profile (type 3). Two accessions of related species showed another novel profile (type 4). The major anthocyanins were identified as delphinidin 3-(p-coumaroylrutinoside)-5-glucoside (nasunin) (type 1), delphinidin 3-rutinoside (type 2), delphinidin 3-glucoside (type 3), and petunidin 3-(p-coumaroylrutinoside)-5-glucoside (petunidin 3RGc5G) (type 4). Delphinidin 3-caffeoylrutinoside-5-glucoside (delphinidin 3RGcaf5G) was isolated from the hybrid (F1) plants of a type 1 cultivar and a type 3 germplasm. Among the five purified anthocyanins, delphinidin 3RGcaf5G showed the highest radical-scavenging activities toward both 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and linoleic acid radical, followed in order by nasunin and petunidin 3RGc5G.     

Analysis of rice <Emphasis Type="Italic">RNA-dependent RNA polymerase 1</Emphasis> (<Emphasis Type="Italic">OsRDR1</Emphasis>) in virus-mediated RNA silencing after particle bombardment

RNA-dependent RNA polymerases (RDRs) play a key role in various RNA silencing pathways in many organisms. Using the nucleotide sequence of SGS2/SDE1/RDR6 in Arabidopsis as the search query for sequences that flank the insertions of rice retrotransposon Tos17, we selected rice mutant lines (OsRDR1). RT-PCR analysis showed that OsRDR1 mRNA was undetectable in leaves and calli of the mutants, while it was detected in wild type. RNA silencing was induced by particle bombardment to investigate any effects of OsRDR1 on RNA silencing with β-glucuronidase or green fluorescent protein DNA/RNA in the mutant lines. The results showed that RNA silencing was impaired in these mutant lines by inverted repeat (IR) DNA or in vitro transcribed double-stranded RNA. Further, the mutant lines were bombarded with Brome mosaic bromovirus (BMV, a ssRNA virus) or Wheat dwarf geminivirus (WDV, a ssDNA virus), each carrying the IR sequence of a reporter gene. As a result, RNA silencing was impaired by BMV. Interestingly, however, it was not impaired by WDV. Thus we propose that OsRDR1 is required for RNA silencing mediated by Bromovirus, but not by Geminivirus in this system.