Evaluation of genetic trends and determination of the optimal number of cumulative records of parity required in reproductive traits in a Large White pig population

Genetic improvement of the reproductive performance of pigs is important for pig breeding despite their low heritabilities. The objectives of this study were to investigate the effectiveness of selection concerning reproductive traits and to determine the optimal number of parity records required for accurate estimation of breeding values (BVs) in the open population of a commercial pig breeding company. The study used records of 2220 purebred Large White pigs (9845 litters) farrowed between 1998 and 2009 in the two herds of the Pacific Ocean Breeding Co. Ltd. The traits studied included farrowing interval (FI), total number of piglets at birth (TNB), average weaning weight per litter (AWW), and raising rate (RR). A statistical model was applied to the 4‐trait repeatability animal model. The heritabilities of FI, TNB, AWW and RR were low. The genetic trends in TNB (h² = 0.09) showed approximately 1.0 increase in 6 years from 2003 to 2008. The predicted error variances indicated that up to fourth parity records are necessary for accurate genetic evaluation. The present study results indicated that even reproductive traits with low heritability can be improved.     

HPLC fluorometric determination of natural phytoplankton phycocyanin and its usefulness as cyanobacterial biomass in highly eutrophic shallow lake

A method for HPLC determination of phycocyanin in phytoplankton samples using gelchromatography with a fluorescence detector was developed to examine the use of phycocyanin as an index of the appearance and progress of cyanobacterial blooms in highly eutrophic lake. At least two types of phycocyanin with different molecular weights, each spectroscopically different from phycoerythrin and allophycocyanin, were found in natural phytoplankton samples. Changes in phycocyanin concentrations were clearly coupled to changes in chlorophyll-a concentrations during June to October while cyanobacterial blooms were occurring. The chlorophyll-a to phycocyanin relationship was linear at chlorophyll-a concentrations of less than 250 μg L^?1. The relationship between cyanobacterial carbon and phycocyanin concentration was also linear, suggesting that phycocyanin content may be a useful index of cyanobacterial biomass in highly eutrophic lakes where large cyanobacterial blooms occur.     

Spore-breaking capabilities of collembolans and their feeding habitat within sporocarps

To examine the relationship between the spore-breaking capability of collembolans and their localization within fungal sporocarps we investigated the proportion of broken spores in the feces of four collembolan species of the genus Hypogastrura using the spores of Hypsizygus marmoreus and analyzed the spatial distribution of the collembolan species within sporocarps as an index of their feeding habits. The collembolan species with a higher capability to break spores were observed more frequently from the spore-bearing surfaces of sporocarps. The collembolan species with a lower capability to break spores were found more frequently from the non-spore-bearing interiors of the sporocarps. These results suggest that the relative value of spores in the diet varied with the capability of collembolans to break spores.     

Acidity neutralization mechanism in a forested watershed in Central Japan

The contributions of cation exchange and mineral weathering to the neutralization of acidity in the Jingahata watershed in central Japan were estimated through a laboratory weathering experiment and runoff chemistry measurements. The laboratory experiment was conducted in a stirred-flow reactor for a whole soil sample collected from the C horizon in the watershed. The concentration ratios of base cations (Ca²⁺, Mg²⁺, K⁺ and Na⁺) to Si (BC/Si) released during the steady-state stage of the laboratory experiment were in good agreement with the ratios of the net flux of base cations to the flux of Si in the streamwater (BC _{N ET}/Si _L).This result suggests that the acidity in the watershed is neutralized primarily by mineral weathering without causing a net loss of base cations from exchange sites. The alkalinity/acidity balance estimated for the watershed shows that the total weathering rate of base cations is approximately 3.26 keq ha^?1 yr^?1. Weathering of plagioclase (An₄₁) contributes 83% of the total weathering rate. The dominant acidity source is CO₂ released within the soil horizons, accounting for roughly 85% of the total acidity flux (3.20 keq ha^?1 yr^?1). This high internal production of acidity suppresses the relative importance of atmospheric acidity inputs (0.3 keq ha^?1 yr^?1).     

Analysis of hop-derived terpenoids in beer and evaluation of their behavior using the stir bar-sorptive extraction method with GC-MS

Hop aroma components, which mainly comprise terpenoids, contribute to the character of beers. However, pretreatments are necessary before analyzing these components because of their trace levels and complicated matrixes. Here, the stir bar-sorptive extraction (SBSE) method was used to detect and quantify many terpenoids simultaneously from small samples. This simple technique showed low coefficients of variation, high accuracy, and low detection limits. An investigation of the behavior of terpenoids identified two distinct patterns of decreasing concentration during wort boiling. The first, which was seen in myrcene and linalool, involved a rapid decrease that was best fitted by a quadratic curve. The second, which was observed in beta-eudesmol, humulene, humulene epoxide I, beta-farnesene, caryophyllene, and geraniol, involved a gentle linear decrease. Conversely, the concentration of beta-damascenone increased after boiling. As the aroma composition depended on the hop variety, we also examined the relationship between terpenoid content and sensory analysis in beer.     

Chemical characteristics and potential source of fulvic acids leached from the plow layer of paddy soil

To understand better the chemical characteristics and source of dissolved organic matter (DOM) leached from the plow layer of rice paddies, a lysimeter study was conducted, which simulated submerged paddy topsoil during rice growth. The fulvic acid (FA) fraction in the percolation water from the lysimeter was collected by adsorption onto insoluble polyvinylpyrrolidone (PVP), and the temporal variations in its elemental composition, molecular size distribution, IR spectra, ¹³C CPMAS NMR spectra, and δ¹³C values were investigated. The proportion of the FA fraction to bulk DOM varied greatly, but the chemical characteristics of the FA fraction did not change appreciably during the experimental period. Thus, it is considered that the changes in the DOM composition in percolation water were mainly due to the differing contributions of the FA fraction. Further, to investigate the source of the FA fraction in the leachate, the chemical characteristics of the FA fraction in the leachate were compared with those extracted from the plow layer soil. A sequential extraction of the FA fraction was conducted using a sequence of water, 0.25 M Na₂SO₄, 0.1 M Na₄P₂O₇ (pH 7.0), 0.1 M Na₄P₂O₇ (pH 10.5), and NaBH₄+0.1 M Na₄P₂O₇ (pH 10.5). It was found that the water- and 0.25 M Na₂SO₄-extractable fractions, which were most mobile, were not the only source of the FA fraction in the leachate. The small molecular size sub-fraction of the NaBH₄+0.1 M Na₄P₂O₇ (pH 10.5)-extractable FAs, most of which are probably bound mainly to iron oxides, are considered to be another source of the FA fraction leached from the plow layer of paddy fields.     

Determination of organic acids by high-performance liquid chromatography with electrochemical detection during wine brewing

Voltammetric determination of acids by means of the electrochemical reduction of quinone was applied to high-performance liquid chromatography (HPLC) with electrochemical detection (ED) for determining organic acids in fruit wines. A two-channel HPLC-ED system was fabricated by use of an ion-exclusion column and an electrochemical detector with a glassy carbon working electrode. Aqueous solution of 0.1 mM HClO(4) and ethanol containing 2-methyl-1,4-naphthoquinone served as a mobile phase and reagent solution, respectively. Determination of acetic, citric, lactic, malic, succinic, and tartaric acids was made by measuring the peak areas of the flow signals due to the reduction current of quinone caused by the eluted acids. The peak area was found to be linearly related to the acid amount ranging from 0.1 to 40 nmol per 20 microL injection. The present method was characterized by reproducibility with the simple and rapid procedure without derivatization of analytes. The method was shown as an effective means for following acid contents in fruit juices during fermentation with wine yeast.     

Change of plasma insulin-like growth factor-1 (IGF-1) concentration with early growth in Japanese beef cattle

The aim of the present study was to examine the change in plasma insulin‐like growth factor‐1 (IGF‐1) concentration with early growth, changes of bodyweight (BW) and relative dairy gain (RDG) in the pre‐ (PRW) and postweaning periods (POW) in Japanese beef cattle, and relationships with metabolites. A total of 33 calves, 22 Japanese black, 6 Japanese shorthorn and 5 of their crossbreed were studied. Insulin‐like growth factor‐1 and metabolite (glucose, triacylglycerol, nonesterified fatty acid) levels in the plasma, from jugular vein blood taken every month, were measured along with BW. Insulin‐like growth factor‐1 in POW increased dramatically with increase of BW (P < 0.05), and the correlation was positive at 0.52 (P < 0.01). Glucose levels correlated significantly with BW, RDG and IGF‐1 (P < 0.01). Metabolic required calorie correlated positively with IGF‐1 (P < 0.01). Also, correlations of BW in POW, with BW and RDG in PRW were positive (P < 0.01). Growth in PRW would be influenced by maternal effects, while active self‐secretion of IGF‐1 in POW might contribute to POW growth. These factors suggested that to increase growth in PRW, maintaining enough maternal effect and IGF‐1 level in POW, was important for establishing better growth after weaning.     

Precise, simple screening for resistance in potato varieties to common scab using paper pots

Resistance to common scab pathogen Streptomyces turgidiscabies of seven potato varieties was compared in the field with a newly developed paper pot method. Seedlings raised in soil in paper pots containing inocula at 1 × 10³ to 10⁷cfu/g soil were transplanted into a scab-free field and grown for 3 months. The disease severity of the seven varieties in the field trials differed in iteration and from year to year, even though their resistance levels were approximately similar at the expected levels. With the paper pot method, the seven varieties had different resistance levels, which were almost completely consistent with the results of the field trials, at more than 1 × 10⁵cfu/g soil. Significant differences in disease severity between resistant and susceptible varieties were observed (P = 0.05) for 2 years, and the resistance level of the varieties was elucidated.