Effects of feeding methods on eating frustration in stabled horses

Five feeding methods were tested in stabled horses: (i) cutting hay (hay was cut into 5 cm lengths), (ii) delaying feeding time (feeding was delayed until 1 h after the usual time), (iii) increasing the feeding frequency (hay was divided into two portions; one half was given at the normal time and the other 1 h later), (iv) increasing the feeding locations (hay was available at three locations), and (v) increasing the hay varieties (three species of hay were used). The behavioral durations in the 2 h after the experimental feedings were compared with those after usual feeding. In the cutting hay treatment, hay‐eating time decreased (P < 0.05), whereas bedding‐eating time and resting time tended to increase. In the delaying feeding time treatment, bedding investigation time increased (P < 0.01) and hay‐eating time tended to increase. In the increasing the feeding frequency treatment, hay‐eating time tended to increase. In the increasing the feeding locations treatment, bedding investigation time tended to decrease. In the increasing the hay varieties treatment, resting time tended to decrease and hay‐eating time tended to increase. It was suggested that the former two feeding methods might stimulate and the latter three feeding methods might suppress eating frustration in terms of increasing consummatory behavior (eating) and decreasing appetitive (investigating) and displacement behavior (resting).     

Pathogenic and Genetic Variation in the Japanese Strains of Fusarium oxysporum f. sp. melonis

ABSTRACT Pathogenic variation among 41 Japanese strains of Fusarium oxysporum f. sp. melonis was analyzed by pathogenicity tests with muskmelon, oriental melon, and oriental pickling melon cultivars. Based on pathogenicity to muskmelon cvs. Amus and Ohi and oriental melon cv. Ogon 9, 41 strains were divided into 3 groups that corresponded completely to Risser's races 0, 2, and 1,2y. To further characterize pathogenic variation within the forma specialis and races, strains were assayed for pathogenicity to 42 additional muskmelon, oriental melon, and oriental pickling melon cultivars. All strains of race 1,2y were pathogenic to all cultivars tested. Strains of race 0 were divided into six variants based on differences in pathogenicity to three muskmelon cultivars; strains of race 2 also were classified into six variants based on differences in pathogenicity to two muskmelon cultivars and one oriental melon cultivar. Genetic variation among strains was analyzed by DNA fingerprinting with four repetitive DNA sequences: FOLR1 to FOLR4. Thirty-six fingerprint types were detected among forty-one strains by pooling results of fingerprinting with four probes. Cluster analysis showed distinct genetic groups correlated with races: the fingerprint types detected in each of races 2 and 1,2y were grouped into a single cluster, and two distinct genetic groups were found in race 0. However, pathogenic variation detected within races 0 and 2 could not be differentiated based on the nuclear markers examined.     

Alternaria Leaf Spot on Mealycup Sage (<Emphasis Type="Italic">Salvia farinacea </Emphasis>Benth.) Caused by <Emphasis Type="Italic">Alternaria alternata </Emphasis>(Fr.) Keissler

In June 1995, a disease causing round to irregular-shaped, water-soaked, brown to blackish brown spots on mealycup sage (Salvia farinacea Benth.) was found in Atsugi-shi, Kanagawa Prefecture, Japan. The symptoms were seen only on leaves, not on neither flower petals or stems. The disease was also found in Setagaya-ku, Tokyo, Memambetsu-cho, Hokkaido and Shimoda-shi and Matsuzaki-cho, Shizuoka. An Alternaria sp. was frequently isolated from these diseased plants. The isolates were severely pathogenic to mealycup sage and caused lesions on the inoculated leaves. The isolates were also weakly pathogenic on scarlet sage (S. splendens Sellow ex Roem. and Schult.) but not on any other Labiatae plants tested. Based on morphological characteristics, such as size of conidia, chain number, and the short beak on conidia, the causal fungus was identified as Alternaria alternata (Fr.) Keissler. This report is the first on a mealycup sage disease caused by A. alternata. Because the symptom was restricted to the leaf, the common name of Alternaria leaf spot was proposed. Received 30 August 2002/ Accepted in revised form 18 November 2002     

Chronological analysis of canine parvovirus type 2 isolates in Japan

Fifty-five canine parvovirus type 2 (CPV) samples, 12 fecal specimens and 43 cell culture isolates, were examined for their genetic characteristics of VP2 gene. They were collected from the diseased dogs at various districts of Japan during 27 years from 1980 to 2006. A fragment of VP2 gene was analyzed by restriction fragment length polymorphism assay and DNA sequencing. The original antigenic type 2 of CPV (CPV-2) was no longer found in the samples since 1984, and two antigenic variants CPV-2a and CPV-2b replaced CPV-2 as predominant types for about 5 years from 1982. A new genetic variant of prototype CPV-2a with non-synonymous substitution at the VP2 amino acid residue 297 from Ser to Ala was first detected in 1987. New CPV-2b with the same amino acid substitution at position 297 as new CPV-2a was also detected from the samples collected in 1997. Since then new CPV-2b has been the predominant CPV over the field of Japan. Several additional amino acid substitutions were detected in the VP2 gene of some recent CPV strains. Neither CPV-2c(a), CPV-2c(b), nor "Glu-426" of the antigenic variants previously found outside the country was detected in any samples tested. Reactivity of new CPV-2a and 2b variants against antibodies produced by the current vaccine products was determined by a cross hemagglutination-inhibition test. The recent field CPV isolates reacted more efficiently to the antibodies produced in dogs vaccinated with the new CPV-2b vaccine strain than the conventional CPV-2 vaccine strain.     

Difference Between Tetrodotoxin and Saxitoxins in Accumulation in Puffer Fish Takifugu rubripes Liver Tissue Slices

In vitro accumulation of tetrodotoxin (TTX) and paralytic shellfish toxin (PST) in tiger puffer fish Takifugu rubripes was investigated using liver tissue slices. When T. rubripes liver slices were incubated with Leibovitz’s L-15 medium containing 0.13 mM TTX at 20 °C in air with saturated humidity, they accumulated 21.5 ± 7.3 μg TTX g⁻¹ liver after the incubation for 12 h and increased to 55.3 ± 8.2 μg TTX g⁻¹ liver at 48 h. In the incubation of T. rubripes liver slices with 0.13 mM PST-containing medium, PST was detected 6.3 ± 0.9 μg g⁻¹ liver at 12 h and reached a plateau thereafter. These results reveal the difference between TTX and PST in accumulation in T. rubripes liver tissue slices. To examine the variation in PST accumulation among fish species, the liver tissue slices from tiger puffer fish T. rubripes, parrot-bass Oplegnathus fasciatus and green ling Hexagrammos otakii were incubated at a concentration of 0.027 mM PST. The toxin contents of 3.0 μg g⁻¹ liver were observed at 8 h regardless of fish species but were not increased subsequently, showing no variety among these three species as to accumulation patterns of PST. It is noted that the tiger puffer fish T. rubripes liver specifically accumulate TTX in preference to PST.     

不同温度条件下添加剂对青贮苜蓿细胞壁成分和体外干物质消化率的影响

用第2茬紫花苜蓿草,采用交叉分组设计调制了青贮。试验设20℃、30℃和40℃3个贮藏温度区,设对照(CON)、添加0.0004%乳酸菌(LAB)、添加0.005%纤维素酶(CEL)和添加0.0004%乳酸菌 0.005%纤维素酶(MIX)4个添加处理。贮存55d开封后测定青贮的细胞壁成分(总纤维-OCW、低消化性纤维-Ob、高消化性纤维-Oa)含量和体外干物质消化率(IVDMD)。结果有以下几种倾向:添加CEL和MIX可使青贮的OCW和Ob含量减少;添加LAB和MIX可提高青贮的IVDMD;添加CEL可降低青贮的IVDMD;在20℃~40℃,随贮藏温度的升高,青贮的Oa含量和IVDMD提高,Ob含量降低。     

Identification of dimethylarsinic acid as the major arsenic compound in fish sauce by liquid chromatography/electrospray ionization-mass spectrometry

ABSTRACT:   Arsenobetaine, the major arsenic compound in marine animals, is substantially non-toxic. It is, however, possible that arsenobetaine undergoes bacterial transformation during manufacturing of fermented fishery products. In the present study, therefore, three types of fish sauce were examined for arsenic concentrations and species compared with those in the raw materials (sardine, Japanese sandfish and Japanese common squid). Arsenic concentrations of the three types of fish sauce were almost equivalent to those in their raw materials, suggesting no accumulation of arsenic during fermentation. Arsenic speciation was performed by a combination of cation-exchange liquid chromatography (LC) and electrospray ionization (ESI)-single quadrupole mass spectrometry (MS). Optimal conditions of LC/ESI-MS were established to analyze seven arsenic compounds (arsenate, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine, trimethylarsine oxide, arsenocholine and tetramethylarsonium ion) found in biological samples. When analyzed by LC/ESI-MS, the major arsenic compound in the raw materials was arsenobetaine as expected, while not arsenobetaine but dimethylarsinic acid was identified as the major arsenic compound in the three types of fish sauce. These results suggest that arsenobetaine in the raw materials is converted to dimethylarsinic acid but not to arsenate with high toxicity by bacterial actions during manufacturing of fish sauce.     

Attachment and infection to MA104 cells of avian rotaviruses require the presence of sialic acid on the cell surface

To determine the characters of receptors on target cells for avian rotaviruses, the receptors on MA104 cells for the pigeon rotavirus PO-13, the turkey rotaviruses Ty-1 and Ty-3, and the chicken rotavirus Ch-1 were analyzed. Pretreatment of MA104 cells with neuraminidase greatly reduced the infection by all of the four avian rotavirus strains. Binding of the cell-attachment protein, purified VP8 expressed in bacteria, of strain PO-13 to MA104 cells was also inhibited by pretreatment of cells with neuraminidase. These findings suggest that avian rotaviruses primarily utilize sialic acid-containing molecules as receptors on MA 104 cells.     

Detectionin situ of endophyte withinTricholoma matsutake/Pinus densiflora mycorrhizal roots

Tricholoma matsutake/Pinus densiflora mycorrhizas andP. densiflora roots were collected from beneath matureT. matsutake fruit-bodies in a Shiro in central Japan and investigated for evidence of endophytic infection.Tricholoma matsutake infection was determined microscopically on cleared, bleached and stained mycorrhizas by the presence of both a thin, discontinuous mantle and highly branched, sparingly septate Hartig net mycelium within the root cortex. Endophytic infection of Matsutake mycorrhizas was characterized by intracortical sclerotia, simple septate mycelium within the cortex and vascular cylinder and intracellular spore masses within the root cortex. This research was supported by a grant from the Bio-oriented Technology Research Advancement Institution (BRAIN).     

Only two weeks are required forTricholoma matsutake to differentiate ectomycorrhizal Hartig net structures in roots ofPinus densiflora seedlings cultivated on artificial substrate

There has been conflicting debate over many years regarding the trophic status ofTricholoma matsutake (Ito et Imai) Sing., and further investigations are necessary to better understandT. matsutake physiology, particularly carbon nutrition, during ectomycorrhizal symbiosis. For this purpose, we developed a technique to rapidly synthesizein vitro ectomycorrhizas betweenPinus densiflora Sieb. et Zucc. andT. matsutake on artificial substrate (vermiculite: perlite: peat: beech sawdust; 5:5:1:1.), without added sugar in the nutrient solution. Only 1 week was required before the first rudimentary Hartig net ‘palmetti’ could be observed in roots. Well-developed Hartig net structures appeared in taproots after 2 weeks and in lateral roots after 3 weeks. Such rapid root infection may be attributed to the quality of the substrate and the inoculum used. This research was supported by a grant from the Bio-oriented Technology Research Advancement Institution (BRAIN).