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Volume 70, Issue 2
Displaying 1-7 of 7 articles from this issue
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Fugaku AOKI, Senkiti SAKAI, Kaoru KOHMOTO1999 Volume 70 Issue 2 Pages 53-60
Published: March 25, 1999
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSTo investigate the role of Ca2+ on the regulatory mechanism of hyperactivation, mouse sperm were treated with a calcium ionophore, ionomycin and a calmodulin inhibitor, W-13, and were analyzed for swimming pattern and flagellar bending. On the successive frames of photographs, the linearity of swimming and the bend angle were measured. Both reagents induced a non-linear swimming pattern as is observed in spontaneously hyperactivated sperm. However, changes in flagellar bending occurred in a different manner. After the occurrence of hyperactivation, the bend angle in the midpiece region was increased to the same direction as the curve of hook-shaped heads. Treatment with W-13 or ionomycin plus EGTA also increased the bend angle to that direction, whereas ionomycin plus Ca2+ increased it to opposite direction. The analysis for asymmetry of flagellar bending also revealed that the treatment with W-13 increased asymmetry to the same direction as the curve of head as is observed in spontaneously hyperactivated sperm and that ionomycin plus Ca2+ increased it to opposite direction. These results suggest that the depression of function of machinery controlled by Ca2+ is involved in the mechanism by which the sperm begin hyperactivated motility.View full abstractDownload PDF (663K) -
Chisato HARADA, Yutaka NAKAMURA, Hajime MINATO1999 Volume 70 Issue 2 Pages 61-66
Published: March 25, 1999
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSThe conditions of NaOH treatment of rice straw to improve digestibility were investigated by varying the concentrations of NaOH and changing the length of the treatment period. The neutral detergent fiber (NDF) and crude hemicellulose (CH) contents of straw remarkably decreased, as increasing the level of NaOH treatment from 1 to 4%. As the treatment period with NaOH proceeded from 0 to 21 days, the NDF, CH, acid detergent fiber (ADF), crude cellulose, and acid detergent lignin (ADL) contents in straw decreased. Lignin contents determined by the three lignin analytical methods were positively correlated with each other, but acetyl bromide lignin (AcBrL) value was significantly greater than Klason lignin (KL) and ADL values. The lignin contents of straw were reduced by NaOH treatment, and the degree of reduction was dependent on NaOH concentrations. In situ digestibilities of straw dry matter (DM) were negatively correlated with lignin contents. The degree of correlation for lignin values determined by the three methods with digestibility was similar, but AcBrL value was strongly correlated with DM digestibility. The increased in situ DM digestibility of NaOH treated straw suggests that NaOH treatment can effectively improve the nutritive value of rice straw for use as a ruminant feedstuff.View full abstractDownload PDF (417K) -
Narito ASANUMA, Miwa IWAMOTO, Tsuneo HINO1999 Volume 70 Issue 2 Pages 67-73
Published: March 25, 1999
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSThe metabolic origin of formate, a substrate for methanogenesis in the rumen, was investigated by in vitro culture experiments with mixed ruminal microbes harvested from a goat. Since formate was rapidly metabolized to methane, formate was not detected in cultures of a usual mixed-microbial population. Therefore, methanogenesis was completely suppressed with anthraquinon, a methanogen inhibitor. This condition brought about the accumulation of H2, which in turn caused the accumulation of formate by suppression of the reaction from formate to H2. Analysis on the stoichiometric relationship between substrates and products revieled that formate is produced from organic acids that are related with the glyoxylate cycle, such as citrate, isocitrate, 2-oxoglutarate, glyoxylate, and oxalate, by a pathway other than the pyruvate formate lyase reaction, which is the major route of formate production in the usual rumen. Especially formate production from oxalate may be important, because plants sometimes contain a large amount of oxalate.View full abstractDownload PDF (518K) -
Michiru FUKASAWA, Shusuke SATO, Aya NISHIWAKI, Kazuo SUGAWARA1999 Volume 70 Issue 2 Pages 74-80
Published: March 25, 1999
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSThe objecting of this study was to examine and discuss how experienced cattle influence behaviour, especially grazing behaviour, of unexperienced calves. (1) In experiment 1, 10 castrated calves and 2 cows were grazed in an artificial pasture for one month to familiarize and interact with each other. Then they were separated into 2 groups: one had 4 calves (M1) with 2 cows and another had 6 calves only (C1). Two groups grazed separately on each native pasture with vegetation similar to each other. Grazing time, travelling speed and variety of grazed plants and drinking frequency of calves were compared. C1 behaved nervously only at the beginning of grazing: they moved more, grazed less and they drank more than M1. Later calves in both groups behaved in the same way. (2) In experiment 2, 6 grazing unexperienced calves and 2 grazing experienced heifers were grouped into 2: one consisted of 2 calves (M2) with 2 heifers and another consisted of 4 calves only (C2). The 2 groups were each grazed on artificial pasture. Grazing time and rate of eating were compared between groups. Grazing time of M2 was significantly longer (P<0.05) than C2. Rate of eating in M2 was significantly higher (P<0.01) than in C2. It is thought that the existence of experienced cattle influences behaviour of calves under grazing situations.View full abstractDownload PDF (553K) -
Satomi ISHII, Masanori KIKUCHI, Kei MURAMATSU, Syouichi TAKAO1999 Volume 70 Issue 2 Pages 81-89
Published: March 25, 1999
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESS"Chigo", a traditionally fermented mares' milk in Inner Mongolia, China (known as kumiss in Russia) was used in this study. We investigated microbial flora and proliferation properties using lactic acid bacteria and yeast isolated from "Chigo". Mixed strains of the isolates were cultivated in 10% reconstituted skim milk (RSM) medium, and the combination of Lactobacillus paracasei subsp. tolerans (LB) and Kluyveromyces marxianus var. lactic (KM) was found to produce the highest quantity of lactic acid. The nutrient reqirements of LB were investigated by omission test and eight amino acids (Ala, Val, Phe, Ser, Thr, Glu, Lys and Arg) and seven vitamins (thiamin, riboflavin, niacin, pantothenic acid, biotin, pyridoxine and folic acid) were found to be essential. When the above mentioned amino acids and vitamins were added to the RSM medium, glutamic acid, serine, folic acid and niacin showed highly stimulatory effect on lactic acid production followed by addition of the supernatant of the yeast culture and the cell-free extract of the yeast. It is thought that nutrients for the growth of lactic acid bacteria may have remained in the cell-free extract of the yeast. Amino acids excreted by KM were analyzed by an amino acid analyzer. Results suggest that a large amount of peptides accumulated in the mixed culture may be responsible for the higher number of viable cells and increased production of lactic acid in the mixed culture containing LB and KM, compared with the single culture of the LB.View full abstractDownload PDF (680K) -
Hideo HASHIMOTO, Kazuyuki YAMAZAKI, Fang HE, Manabu KAWASE, Masataka H ...1999 Volume 70 Issue 2 Pages 90-97
Published: March 25, 1999
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSIn order to evaluate the hypocholesterolemic effect of Lactobacillus casei subsp. casei TMC 0409 strain (TMC 0409), an isolate from 'Dadih', an Indonesian traditional fermented dairy food, Sprague-Dawley rats were fed cholesterol containing diets supplemented with fermented milk cultured with TMC 0409, skim milk and TMC 0409 lyophilized cells. No significant inhibitory effect was observed in the rats fed fermented milk and skim milk after 14 days feeding. But the increase of serum cholesterol was suppressed (36%) in the rats fed TMC 0409 lyophilized cells. Total cholesterol, HDL-cholesterol, triglyceride and phospholipid in serum, neutral steroid and bile acids in feces, cholesterol and triglyceride in liver were analyzed in the rats fed TMC 0409 cells after 14 days feeding. Total cholesterol and phospholipid were significantly decreased compared to those of control group (P<0.01), however HDL-cholesterol was significantly increased (P<0.05). Serum triglyceride was also decreased but the difference was not significant. From these results, the inhibition of increase of serum cholesterol in rats fed TMC 0409 cells was considered to have resulted from the reduction of LDL+VLDL-cholesterol. Meanwhile, the accumulation of triglyceride in the liver was inhibited significantly compared with the control group (P<0.05), and the excretion of bile acid in the feces was also enhanced significantly (P<0.01). These results imply that strain TMC 0409 can alter the serum cholesterol concentration, especially LDL+VLDL-cholesterol by enhancing the excretion of bile acids in the feces.View full abstractDownload PDF (572K) -
Xiang-Jun SHEN, Taisuke BABA, Atsushi IWASAWA, Takao NAKAMURA1999 Volume 70 Issue 2 Pages 98-100
Published: March 25, 1999
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSIn accordance with chicken mtDNA sequences, three pairs of primers were designed for the cytochrome b (Cyt b) gene. Three mtDNA fragments were amplified via PCR from silky fowl total genomic DNA in blood. The PCR products were used for detecting the DNA sequences by the direct-sequencing method. The silky fowl cytochrome b gene consisted of 1143bp nucleotides, encoded for a 380 amino acid protein, and showed 99.4% and 86.8% homology with White Leghorn and Japanese quail, respectively. The homology of the amino acid sequence of the Cyt b gene of silky fowl and White Leghorn birds was 100%, with a corresponding 93.1% between silky fowl and quail. The sequences reported in this paper have been deposited in the GenBank database (accession no. AF 102874).View full abstractDownload PDF (232K)
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