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1.
2.
This experiment was conducted to determine the effect of ruminal dosing of a mechanical stimulating brush on rumination time, ruminal passage rate and rumen fermentation status in steers fed a concentrate diet at maintenance level. Animals were dosed three Rumen Faibu (RF) per head through the rumen fistulae (RF treatment) and not dosed (control) in a change‐over design. The organic cell wall content of the concentrate diet was 12.7% of dry matter. Daily time spent on rumination was very short in both treatments with 24 min in RF treatment and 15 min in control. The turnover rate of ruminal fluid in RF treatment was higher than that in control. There were no differences in ruminal pH and total volatile fatty acid concentration between RF treatment and control. Acetic and butyric acid concentrations were not different between the treatments. Propionic acid concentration tended to be higher in the animals on RF treatment than in control animals. The RF dosing in Holstein steers fed a low fiber diet did not affect the rumination time, but increased rumen digesta passage rate and ruminal propionic acid production. 相似文献
3.
Tsutomu MATSUMOTO Yuichiro NARA Hiromitsu FURUYA Harumi TAKAHASHI Kiichi TAIRAKO Hideki YAMAMOTO 《Journal of General Plant Pathology》2002,68(4):382-384
L11A-Fukushima (L11A-F) derived from attenuated isolate LuA of Tomato mosaic virus (ToMV) has the highest ability to cross protect against virulent ToMV among LuA and its derivatives and is stably inherited.
Growth, yield, fruit quality and symptom attenuation of inoculated tomato plants did not differ significantly between L11A-F and L11A. The infectivity of progeny viruses in tomato infected with LuA-F was less than 4% of that with virulent ToMV. From these
results, L11A-F appears to possess the properties necessary for practical use. To manage L11A-F strictly, a PCR-based assay to detect trace contamination of virulent ToMV in L11A-F preparations was established.
Received 10 June 2002/ Accepted in revised form 30 October 2002 相似文献
4.
Hiroyuki Matsumoto Masahiro Umehara Hironobu Muroi Yoshimasa Yoshitake Shinji Tsuyumu 《Journal of General Plant Pathology》2003,69(3):189-193
Erwinia carotovora subsp. carotovora (Ecc) is a causal agent of soft-rot diseases in a wide variety of plants. Here, we have isolated nonmotile mutants in Ecc
by in vivo insertional mutagenesis using a transposon Tn5. The sequence disrupted by the Tn5 insertion in YMU1 and YMU5 mutants was highly homologous to that of flhC and flhD genes, respectively. They are involved in the initiation of the expression of flagellum-related genes in many gram-negative
bacteria such as Escherichia coli and Salmonella. With electron microscopy, the flhC and the flhD homolog mutants were shown to be aflagellate. Furthermore, the virulence of these mutants was greatly reduced in Chinese
cabbage and potato compared to that of the parental strain. These results suggest that flagellar formation is required for
the pathogenicity of Ecc.
Received: November 5, 2002 / Accepted: December 2, 2002
Acknowledgments This research was supported in part by Grant-in-Aid (12052210) and by a grant from the Ministry of Education, Culture, Sports,
Science, and Technology of Japan (13073). 相似文献
5.
Identification of sulfonylurea-resistant biotypes of paddy field weeds using a novel method based on their rooting responses 总被引:2,自引:0,他引:2
6.
Masahiro SATOH 《Animal Science Journal》2004,75(2):97-102
The present study evaluated the advantage of mixed‐model techniques over a selection index under different magnitudes of an additional systematic environmental effect (ASEE) in terms of accuracy of prediction and expected genetic gain. The data attempted to simulate a closed herd in a pig breeding program. The base population (G0) consisted of 10 males and 50 females. Six generations (G0 to G5) were selected by using a selection index of three traits without overlapping. Additional systematic environmental constants with four levels in a generation were assigned from a uniform distribution at different ranges. Breeding values of animals in the last generation (G5) were estimated on the basis of an index of individual phenotype (SI‐U), SI‐U adjusted for ASEE using a least‐squares mean (SI‐A), best linear unbiased prediction using an animal model excluding ASEE (AM‐E), and an animal model including ASEE (AM‐I). Accuracy of prediction and expected genetic gain were larger by the animal model than by the selection index, even if heritability of the traits selected was high and ASEE was set to zero. When ASEE was zero, the accuracy of prediction and expected genetic gain given by SI‐U and AM‐I were similar to those given by SI‐A and AM‐E, respectively. However, the differences in accuracy and expected gain between SI‐U and AI‐A and between AM‐I and AM‐E increased as the range of ASEE increased. It was concluded that selection based on an animal model was more effective than index selection, even if the herd environment was uniform and traits with high heritability were selected, and that it should be always included in an evaluation model, however slight any systematic environmental effect may be in a closed herd. 相似文献
7.
Improving management for higher reproduction accelerates genetic improvement in closed herd of swine
Masahiro SATOH 《Animal Science Journal》2004,75(6):499-502
The present study compared responses to selection at different conception rates and litter sizes at weaning in a simulated closed herd in a swine breeding program. The base population consisted of 10 males and 50 females, and 10 generations of selection was practiced by using individual phenotype or best linear unbiased prediction of breeding values for a trait with heritability (h2) of either 0.2 or 0.5. The probability of conception in a single mating was assumed to be 0.8, 0.9 or 1.0. Litter size at weaning was sampled randomly from a normal distribution with mean 8, 10 or 12 and variance 8.1225. Genetic response increased by approximately 6% for h2 = 0.2 and approximately 5% for h2 = 0.5 at generation 10 when conception rate was increased from 0.8 to 1.0. However, litter size at weaning did not affect response to selection. In conclusion, improving conception rate by environmental management increases genetic response indirectly in a breeding program of a closed swine herd. 相似文献
8.
Osamu Yamato Hiroyuki Satoh Naoaki Matsuki Kenichiro Ono Masahiro Yamasaki Yoshimitsu Maede 《Journal of veterinary diagnostic investigation》2004,16(1):39-44
In the present study, laboratory techniques were used to diagnose canine GM2-gangliosidosis using blood and cerebrospinal fluid (CSF) that can be collected noninvasively from living individuals. Lysosomal acid beta-hexosaminidase (Hex) was measured spectrofluorometrically using 4-methylumbelliferyl N-acetyl-beta-D-glucosaminide and 4-methylumbelliferyl 7-(6-sulfo-2-acetamido-2-deoxy-beta-D-glucopyranoside) as substrates. Main isoenzymes A and B of Hex in leukocytes were also analyzed using cellulose acetate membrane electrophoresis. GM2-ganglioside in CSF was detected and determined quantitatively by using thin-layer chromatography/enzyme-immunostaining method with anti-GM2-ganglioside antibody. In normal dogs, Hex activities could be determined in leukocytes, serum, and CSF and the total activities were markedly reduced in all the enzyme sources in a dog with Sandhoff disease. Electrophoresis of a leukocyte lysate from a normal dog showed that the Hex A and Hex B were not separated distinctively with formation of a broad band, whereas there were no bands in electrophoresis of a lysate from a dog with Sandhoff disease, showing a deficiency in the total enzyme activity. GM2-ganglioside could be detected and determined quantitatively in as little as 100 microl of canine CSE GM2-ganglioside in CSF in a dog with Sandhoff disease increased to 46 times the normal level. In conclusion, the methods in the present study are useful for diagnosis of canine GM2-gangliosidosis. These techniques enable definitive and early diagnosis of canine GM2-gangliosidosis even if tissues and organs cannot be obtained. 相似文献
9.
Kumiko TAKEDA Masahiro SATOH Shreeram P. NEOPANE Bahadur S. KUWAR Hari D. JOSHI Nanda P. SHRESTHA Hiroshi FUJISE Mariko TASAI Takahiro TAGAMI Hirofumi HANADA 《Animal Science Journal》2004,75(2):103-110
Dwarf Lulu cattle, the only Bos Taurus type of cattle in Nepal, are raised under severe environments in the mountainous zone of that country. In the present study, the body measurement traits, cytogenetic and molecular genetic characteristics of the Lulu cattle are investigated. Blood samples were collected from 31 animals in four villages (altitudes 2590–3550 m) in the southern part of Mustang. The Lulu cattle had a normal karyotype with 2n = 60, XY or XX. Only one male examined had a large submetacentric X‐chromosome and a small submetacentric taurine type Y‐chromosome. The mitochodrial DNA (mtDNA) genotypes were analyzed by PCR mediated restriction fragment length polymorphisms, displacement (D)‐loop region PCR mediated single strand conformation polymorphisms, and D‐loop region sequences. Many base substitutions were found in the D‐loop region, suggesting that the Lulu cattle originated from at least 10 maternal lines. Three types of mtDNA from these cattle were found, the Bos taurus type (n = 23), the Bos indicus type (n = 6), and the Bos grunniens type (n = 2). In the village at the lowest altitude, four of the five cows were of the Bos indicus type. These results indicated that mtDNA types of the Lulu cattle mostly belong to Bos taurus, but have been hybridized with Bos indicus cattle in lower‐elevation regions in their maternal lineage. 相似文献
10.
Yukino TAMAMURA-ANDOH Nobuyuki TANAKA Keisuke SATO Yoshino MIZUNO Nobuo ARAI Ayako WATANABE-YANAI Masato AKIBA Masahiro KUSUMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):754
We examined the antimicrobial susceptibility of 848 Escherichia coli isolates from 237 feces samples of wild sika deer (Cervus nippon) captured between 2016 and 2019 in 39 of the 47 prefectures of Japan. Five of the 237 wild sika deer (2.1%) carried E. coli with resistance to at least one antimicrobial, and all the resistant isolates showed resistance to tetracycline. The resistant isolates contained antimicrobial resistance genes that were similar to those in E. coli derived from humans and farm animals. Although wild sika deer are not currently likely to be a source for the transmission of antimicrobial resistance in Japan, they can potentially mediate antimicrobial resistance spread by coming into contact with humans, animals, and their surroundings. 相似文献