Studies of foetuses from cows clinically affected with bovine leucosis

Five foetuses varying stages of gestation were recovered from cows showing clinical signs of infection with bovine leukaemia virus (BLV). No pathological changes were found in the foetuses although BLV was isolated from 2 of these foetuses. No antibody to BLV could be detected by virus-neutralisation or immunodiffusion (ID) techniques in these two foetuses, although neutralising antibody alone was detected in one of the other 3 foetuses which were all negative for virus.     

Analysis of cartilage oligomeric matrix protein (COMP) degradation and synthesis in equine joint disease

REASONS FOR PERFORMING STUDY: Cartilage oligomeric matrix protein (COMP) is abundant within cartilage; its turnover and/or degradation have been investigated in various equine joint diseases and it has been suggested that COMP fragmentation might be useful for monitoring such conditions. OBJECTIVES: To determine whether COMP metabolism is compromised in equine osteoarthritis (OA) and whether COMP degradation is a useful joint marker representing cartilage destruction. HYPOTHESIS: A monoclonal antibody (mAb) with a higher affinity for degraded COMP allows discrimination of diseased joints by quantifying COMP levels and fragmentation. METHODS: A mAb (clone14G4) was generated against equine cartilage COMP. The NH2-terminal sequence of enzyme-cut COMP fragments recognised by 14G4 was determined, as was the efficiency of binding to COMP (using a generated COMP peptide). COMP concentration and fragmentation were analysed in synovial fluid (SF) from normal horses and those with OA. RESULTS: The mAb 14G4 had a higher affinity for the smaller fragments of equine COMP, compared with a mAb (clone 12C4) generated against human COMP. The 14G4 epitope was identified as between C134 and F147. The COMP values in OA (mean +/- s.d. 205.8 +/- 90.9 microg/ml) were significantly higher than in the normal (133.1 +/- 31.5 microg/ml) SF. On the immunoblots of OA sample, the proportions of intact COMP were significantly lower, while smaller fragments ranging from 75 to 290 kDa were higher compared with the normal SF. CONCLUSIONS AND POTENTIAL RELEVANCE: The mAb 14G4 reliably detects COMP degradation as well as synthesis, and fragmentation analysis combined with quantification in SF could be useful to study equine OA.     

Variation in floral scent compounds recognized by honeybees in Brassicaceae crop species

Floral scent attracts pollinators. We investigated the floral scent compounds recognized by pollinators in six Brassica crop species, including allogamous species with different genomes and autogamous species with two parental genomes and radish (Raphanus sativus). Biologically active compounds recognized by honeybees were screened from all floral compounds by combined gas chromatography–electroantennogram analysis and their profiles were determined by gas chromatography–mass spectrometry. Fourteen of the 52 compounds were active. All accessions had more than two active compounds, but the compounds greatly differed between the two genera. On the basis of similarities in whether active compounds were presence or absence, their amount and their composition ratio, we divided the Brassica accessions into three to five groups by cluster analyses. Most groups were composed of a mixture of allogamous and autogamous species sharing same genome, indicating that the variation depended on genome, not species. These results suggest that all species require pollinator visits for reproduction, despite their different reproductive systems. However, the inter-genus and intra-specific variations shown by the multiple groups within a species might cause different visitation frequencies by pollinators between genera and among accessions within a species, resulting in insufficient seed production in some accessions or species.     

PCR-RFLP genotypes associated with quinolone resistance in isolates of Flavobacterium psychrophilum

A novel genotyping method for epizootiological studies of bacterial cold-water disease caused by Flavobacterium psychrophilum and associated with quinolone resistance was developed. Polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) was performed on 244 F. psychrophilum isolates from various fish species. PCR was performed with primer pair GYRA-FP1F and GYRA-FP1R amplifying the A subunit of the DNA gyrase (GyrA) gene, which contained the quinolone resistance determining region. Digestion of PCR products with the restriction enzyme Mph1103I showed two genotypes, QR and QS. The difference between these genotypes was amino acid substitutions at position 83 of GyrA (Escherichia coli numbering). The genotype QR indicated an alanine residue at this position associated with quinolone resistance in F. psychrophilum isolates. Of the 244 isolates tested in this study, the number of QR genotype isolates was 153 (62.7%). In isolates from ayu (n=177), 146 (82.5%) were genotype QR. With combination of this technique and previously reported PCR-RFLP genotyping, eight genotypes were observed in F. psychrophilum isolates. Using this genotyping system, the relationships between genotype and host fish species, or locality of isolation, were analysed and are discussed.     

alpha-Glucosidase inhibitory activity of some Sri Lanka plant extracts, one of which, Cassia auriculata, exerts a strong antihyperglycemic effect in rats comparable to the therapeutic drug acarbose

Some Sri Lanka plant stuffs were examined regarding in vitro and in vivo alpha-glucosidase (AGH) inhibitory actions. According to the results, water extracts and methanol extracts of dried fruits of Nelli (Phylanthus embelica), methanol extracts of dried flowers of Ranawara (Cassia auriculata), and water extracts of latex of Gammalu (Pterocarpus marsupium) were found to have a potential AGH inhibitory activity. In particular, Ranawara methanol extract showed the strongest AGH inhibitory activity in vitro preferably on maltase giving an IC(50) value of 0.023 mg/mL and inhibited the maltase activity competitively. As a result of single oral administration of Ranawara (C. auriculata) methanol extract in Sprague-Dawley rats, a significant and potent lowering of blood glycemic response toward maltose ingestion was observed at 30 min after dosing of 5 mg/kg, thus, concurrently suppressed insulin activity. The ED(50) of the extract (4.9 mg/kg) clearly indicated that the antihyperglycemic effect was as potent as that of therapeutic drug, acarbose (ED(50) 3.1 mg/kg).     

Serological differentiation of FIV-infected cats from dual-subtype feline immunodeficiency virus vaccine (Fel-O-Vax FIV) inoculated cats

Feline immunodeficiency virus (FIV) vaccine, Fel-O-Vax FIV, was released for sale in the US in 2002. The antibodies of vaccinated cats interfere with serological assays by currently available FIV diagnostic kits. In this study, we investigated whether it is possible to distinguish serologically cats vaccinated with Fel-O-Vax FIV from cats experimentally or naturally infected with FIV. A total of 153 sera taken from 97 cats were used as serum samples. Enzyme linked immunosorbent assay (ELISA) was performed using whole FIV antigen and formalin treated whole FIV antigen, recombinant-gag (r-gag) antigen, and transmembrane (TM) peptide. Statistical analysis was performed using ELISA optical density (O.D.) values obtained with each antigen as variables. Except for the ELISA O.D. values obtained with r-gag antigen, a significant difference in ELISA O.D. values was observed between the vaccinated and the infected groups. However, it was not possible to distinguish both groups unequivocally. Using discriminant analysis, it was possible to distinguish the two groups with an accuracy of 97.1% with two discriminating variables (ELISA O.D. values obtained with formalin treated whole FIV antigen, and TM peptide), 97.8% with three discriminating variables (ELISA O.D. values obtained with whole FIV antigen, formalin treated whole FIV antigen, and TM peptide). Therefore, it was considered possible to distinguish cats vaccinated with Fel-O-Vax FIV from FIV-infected cats by ELISA using two types of antigens including formalin treated whole FIV antigen and TM peptide, or three types of antigens including formalin treated whole FIV antigen, TM peptide and whole FIV antigen.     

Aboveground biomass equations for individual trees of <Emphasis Type="Italic">Cryptomeria japonica</Emphasis>, <Emphasis Type="Italic">Chamaecyparis obtusa</Emphasis> and <Emphasis Type="Italic">Larix kaempferi</Emphasis> in Japan

Generic equations are proposed for stem, branch and foliage biomass of individual trees in even-aged pure stands of Cryptomeria japonica, Chamaecyparis obtusa and Larix kaempferi. Biomass data was collected from a total of 1,016 individual trees from 247 stands throughout Japan, and five regression models were assessed by root mean square error, mean bias, fit index (FI), and AIC. The results show that a power equation using diameter at breast height (dbh) and height is the most suitable for all species and components. This equation is more accurate than the familiar power equation that uses ‘dbh² height’, and it expresses the greater volume of branch and foliage mass of trees with a lower height/diameter ratio. A power equation using dbh is more reasonable for models with dbh as the only independent variable and more accurate than a power equation using ‘dbh² height’ for estimating branch and foliage mass. Estimating error for branch and foliage mass is larger than that for stem mass, but the entire aboveground biomass can be estimated with an error of less than 19%, except in the case of small trees with dbh less than 10 cm.     

Relationship between adipose maturity and fatty acid composition in various adipose tissues of Japanese Black,Holstein and Crossbred (F1) steers

The amount of monounsaturated fatty acid (MUFA) is intimately related to adipose softness, melting point (MP) and flavor in beef. Stearoyl‐CoA desaturase (SCD) is a main gene involved in MUFA synthesis. Mature adipose tends to be highly saturated, whereas immature or maturing adipose is highly unsaturated when chronologically based, so the degree of non‐saturation can be an index of adipose maturity. In this study, three different adipose tissues (coelomic (CL), perirenal (PR), and subcutaneous (SC)) from three beef breeds with differing slaughter ages (Japanese Black (29.5 months), Holstein (20.1 month), and F1 crossbreed (25.6 months)) were examined to: (i) determine adipose maturity level as indexed by MUFA %; and (ii) determine SCD and other lipogenic gene messenger RNA (mRNA) expression levels in relation to unsaturated fatty acid content. Fatty acid composition was significantly different between adipose tissues (P < 0.05). MUFA amount was high in the following order: SC > CL > PR. This pattern corresponded to SCD mRNA expression profile showing higher expression in SC than CL and PR. However, Japanese black cattle are an exception with CL adipose containing similar UFA % as SC adipose, yet having the lowest SCD mRNA expression level among all adipose tissues tested. Therefore, SCD mRNA expression and MUFA % appear to be directly related; however, differences in SCD mRNA expression among three adipose tissues may reflect differences in the fat development characteristics affected by chronological age of the cattle breeds.     

Physical and mechanical properties of wood after moisture conditioning

Some properties of wood (hinoki:Chamaecyparis obtusa) moisture-conditioned by an adsorption process from a dry state and by two desorption processes (from a water-saturated state and from a state with a moisture content slightly below the fiber saturation point) were investigated. The moisture contents of wood conditioned by the adsorption process and by the desorption process continued to approach to one another for the moisture-conditioning period of over 50 weeks. Accordingly, sorption hysteresis should be regarded as a transitional phenomenon that occurs during the process of approaching the true equilibrium, which requires a long time. The wood conditioned by the desorption process beginning from a water-saturated state showed slightly smaller dimensions than those conditioned by the adsorption process with the same moisture content; however, the wood conditioned by the desorption process from a moisture content below the fiber saturation point showed slightly larger dimensions than those conditioned by the adsorption process. The wood conditioned by the adsorption process from a dry state showed a higher modulus of elasticity and modulus of rupture than did the wood conditioned from a water-saturated state with the same moisture content. The mechanical properties of the wood also varied based on the states at which the desorption process was started. This is a notable characteristic of the relation between the drying condition and the mechanical properties of wood.