Tick infestation of sika deer (Cervus nippon) in the western part of Yamaguchi Prefecture,Japan

Ticks were collected from 94 sika deer (Cervus nippon) hunted in the western part of Yamaguchi Prefecture, Japan from August to November 1999, and March to July 2000. Haemaphysalis longicornis and H. yeni were the dominant species from April to August, while H. flava and H. megaspinosa were dominant in October, November and March. This is the first report of H. yeni in the mainland of Japan. Small numbers of H. kitaokai, Amblyomma testudinarium and Ixodes ovatus were also recorded.     

Cloning and characterization of pea apyrases: involvement of <Emphasis Type="Italic">PsAPY1 </Emphasis>in response to signal molecules from the pea pathogen <Emphasis Type="Italic">Mycosphaerella pinodes</Emphasis>

 Two nucleoside triphosphatase (NTPase) cDNA clones were isolated from a cDNA library of Pisum sativum L., cv. Midoriusui. The genes encoding the cDNAs were designated PsAPY1 and PsAPY2. PsAPY1 included the N-terminal amino acid sequence of an NTPase bound to pea cell wall. The phylogenic analysis indicated that PsAPY1 belongs to an NTPase subfamily responsive to environmental stimuli and that PsAPY2 belongs to a discrete subfamily, the physiological role of which is almost unknown. The adenosine triphosphatase activity of recombinant PsAPY1 was regulated by an elicitor and a suppressor from the pea pathogen Mycosphaerella pinodes. Based on these findings, we discuss the role of NTPases in response to biological stresses. Received: May 27, 2002 / Accepted: July 31, 2002     

Genetic analysis of shiga-toxigenic Escherichia coli isolates from cattle in a limited region

The ecology of shiga‐toxigenic Escherichia coli (STEC) is important in the animal production environment. We investigated fecal shedding of STEC in one town in Miyagi, Japan by multiplex polymerase chain reaction (PCR) targeting shiga toxin gene 1 (stx₁), gene 2 (stx₂) and malB promoter gene, and analyzed the PCR products of stx₁ or stx₂ (54 samples) by direct sequencing. Three of 46 (6.5%) beef cattle in the University Farm of Tohoku University (Kawatabi Farm) and 11 of 70 (15.7%) calves in neighboring dairy farms carried STEC. Rate of detecting genes of stx₁, stx₂ and stx₁₊₂ was 3.4% (4/116), 8.6% (10/116) and 0.9% (1/116), respectively. Serotyping indicated that STEC contaminated farms at different times or through different routes. Isolates harbored no mutation among stx₁, but six (Kawatabi Farm) and 38 (neighboring farms) base substitutions among stx₂, respectively. The diversity of substitutions of stx₂ was observed among farms or even in a farm. Phylogenic analysis revealed that STEC detected in the area were classified into three clusters by the variety of stx₂. Sequence analysis of stx₂ will be one of the tools for clarifying the source of outbreaks and the route of contamination of STEC.     

Comparison of physicochemical properties of 7S and 11S globulins from pea, fava bean, cowpea, and French bean with those of soybean--French bean 7S globulin exhibits excellent properties

Legume seeds contain 7S and/or 11S globulins as major storage proteins. The amino acid sequences of them from many legumes are similar to each other in the species but different from each other, meaning that some of these proteins from some crops exhibit excellent functional properties. To demonstrate this, we compared protein chemical and functional properties (thermal stability, surface hydrophobicity, solubility as a function of pH, and emulsifying properties) of these proteins from pea, fava bean, cowpea, and French bean with those of soybean as a control at the same conditions. The comparison clearly indicated that the 7S globulin of French bean exhibited excellent solubility (100%) at pH 4.2-7.0 even at a low ionic strength condition (mu = 0.08) and excellent emulsion stability (a little phase separation after 3 days) at pH 7.6 and mu = 0.08, although the emulsions from most of the other proteins separated in 1 h. These results indicate that our assumption is correct.     

Lipid content and fatty acid composition of muscle,liver, ovary and eggs of captive-reared and wild silver Japanese eel <Emphasis Type="Italic">Anguilla japonica</Emphasis> during artificial maturation

ABSTRACT:   Changes in lipid content and fatty acid composition of muscle, liver and ovary of captive-reared and wild silver Japanese eel Anguilla japonica were examined during artificial maturation induced by salmon pituitary homogenate (SPH) injections. Although the relative levels of n-3 and n-6 highly unsaturated fatty acids (HUFA) in liver and ovary were higher than in muscle in both captive and wild silver eels before SPH injection, these tended to decrease with maturation. The relative levels of n-6 HUFA in muscle, liver, ovary and eggs of wild silver eels were remarkably higher than those in captive eels. Therefore, we attempted to alter the ratio of n-6 HUFA in eggs by feeding eels a diet supplemented with linoleic acid-rich plant oil. Although the percentage of n-6 polyunsaturated fatty acids to total fatty acids in eggs of eels fed the supplemented diet was similar to wild silver eels, the percentage of n-6 HUFA remained remarkably lower than in wild silver eels. Hence, it appears that the supplemented diet affected the fatty acid composition of eggs, but did not result in much conversion of linoleic acid to its higher homologs in eels.     

DNA markers linked to Pga1, an adzuki bean gene that confers resistance to Cadophora gregata race 1

Brown stem rot (BSR) caused by Cadophora gregata f. sp. adzukicola (syn. Phialophora gregata) is a serious soilborne disease of adzuki bean (Vigna angularis) in Japan. Cultivation of resistant cultivars is the most effective disease control method, therefore the selection of resistant lines is a priority for breeders. BSR-resistant adzuki bean lines have been screened in pathogen-infected fields. However, field selection using the pathogen and artificial inoculation methods is time-consuming and labor-intensive. In the present study, we used 105 F₃ lines derived from a cross between a BSR-resistant cultivar ‘Syumari’ and a susceptible cultivar ‘Buchishoryukei-1’ for BSR inoculation tests. Amplified fragment-length polymorphism (AFLP) analyses with 1024 primer sets revealed that six fragments were polymorphic between resistance and susceptible bulked groups. Five DNA markers (Pg77, Pg118, Pg138, Pg139 and Pg126) were developed from the nucleotide sequences of polymorphic AFLP markers and their flanking regions. Pg118, which was derived from E-ACT/M-ACT-118, was tightly linked to the resistance gene Pga1 and was converted into a codominant marker for its easier use in marker-assisted selection for adzuki bean BSR resistance. Finally, the applicability of the developed markers for BSR resistance was tested on 32 adzuki bean accessions or cultivars.     

Amla (Emblica officinalis Gaertn.) attenuates age-related renal dysfunction by oxidative stress

To investigate the effects of amla on renal dysfunction involved in oxidative stress during the aging process, we employed young (2 months old) and aged (13 months old) male rats and administered SunAmla (Taiyo Kagaku Co., Ltd., Japan) or an ethyl acetate (EtOAc) extract of amla, a polyphenol-rich fraction, at a dose of 40 or 10 mg/kg body weight/day for 100 days. The administration of SunAmla or EtOAc extract of amla reduced the elevated levels of serum creatinine and urea nitrogen in the aged rats. In addition, the tail arterial blood pressure was markedly elevated in aged control rats as compared with young rats, while the systolic blood pressure was significantly decreased by the administration of SunAmla or EtOAc extract of amla. Furthermore, the oral administration of SunAmla or EtOAc extract of amla significantly reduced thiobarbituric acid-reactive substance levels of serum, renal homogenate, and mitochondria in aged rats, suggesting that amla would ameliorate oxidative stress under aging. The increases of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 expression in the aorta of aging rats were also significantly suppressed by SunAmla extract or EtOAc extract of amla, respectively. Moreover, the elevated expression level of bax, a proapoptotic protein, was significantly decreased after oral administration of SunAmla or EtOAc extract of amla. However, the level of bcl-2, an antiapoptotic protein, did not show any difference among the groups. The expressions of renal nuclear factor-kappaB (NF-kappaB), inhibitory kappaB in cytoplasm, iNOS, and COX-2 protein levels were also increased with aging. However, SunAmla or EtOAc extract of amla reduced the iNOS and COX-2 expression levels by inhibiting NF-kappaB activation in the aged rats. These results indicate that amla would be a very useful antioxidant for the prevention of age-related renal disease.     

First record of avian Plasmodium DNA from mosquitoes collected in the Yaeyama Archipelago, southwestern border of Japan

We studied the prevalence of avian Plasmodium in 509 mosquitoes of 9 species collected from the Ishigaki and Iriomote islands in the Yaeyama Archipelago, located southwest from the mainland of Japan. Two identical avian Plasmodium lineages were detected from Culex (Culiciomyia) nigropunctatus. Detected lineages were phylogenetically classified into different clade to avian Plasmodium lineages from birds and mosquitoes in the mainland of Japan but identical to a lineage detected from a resident bird, White-breasted Waterken (Amaurornis phoenicurus). This is the first detection of avian Plasmodium DNA from mosquitoes in the Yaeyama Archipelago and suggested that resident birds might have been infected with an avian Plasmodium lineage specific to the studied area and C. nigropunctatus could be the candidate vector mosquito species.     

Molecular Detection of Avian Pathogens in Poultry Red Mite (Dermanyssus gallinae) Collected in Chicken Farms

Poultry red mite (PRM, Dermanyssus gallinae) is a blood-sucking ectoparasite as well as a possible vector of several avian pathogens. In this study, to define the role of PRM in the prevalence of avian infectious agents, we used polymerase chain reaction (PCR) to check for the presence of seven pathogens: Avipox virus (APV), Fowl Adenovirus (FAdV), Marek’s disease virus (MDV), Erysipelothrix rhusiopathiae (ER), Salmonella enterica (SE), Mycoplasma synoviae (MS) and Mycoplasma gallisepticum (MG). A total of 159 PRM samples collected between 2004 and 2012 from 142 chicken farms in 38 prefectures in Japan were examined. APV DNA was detected in 22 samples (13.8%), 19 of which were wild-type APV. 16S ribosomal RNA (16S rRNA) of MS was detected in 15 samples (9.4%), and the mgc2 gene of MG was detected in 2 samples (1.3%). Eight of 15 MS 16S rRNA sequences differed from the vaccine sequence, indicating they were wild-type strains, while both of the MG mgc2 gene sequences detected were identical to the vaccine sequences. Of these avian pathogen-positive mite samples, three were positive for both wild-types of APV and MS. On the other hand, the DNAs of ER, SE, FAdV and MDV were not detected in any samples. These findings indicated that PRM can harbor the wild-type pathogens and might play a role as a vector in spreading these diseases in farms.