Analysis of the electrophoretic karyotype ofFlammulina velutipes

The karyotype ofFlammulina velutipes (Curt.: Fr.) Sing. was analyzed electrophoretically using contourclamped homogeneous electric field gel electrophoresis and hybridization with DNA probes. The chromosomal DNA from the monokaryon (Fv-4K) and the dikaryon (Fv-4) were resolved into six and eight bands, respectively. The sizes of the chromosomes ranged from 1.9 to 6.0 megabase (Mb) pairs. Each of the separated bands of chromosomal DNA was identified by use of five cloned probes. The number of these chromosomes was estimated to be 6 and 12, respectively; and the size of the entire genome was estimated to be about 20.1 and 38.6Mb, respectively. From a comparison of the hybridization patterns, the existence of allelic chromosomes of different sizes was deduced in the Fv-4 strain.     

Influence of volcanic ash sediments on spore adhesion of the red alga Gelidium elegans from the coastal seabed around Miyakejima Island, Japan

The populations of red alga Gelidium elegans along the coast of Miyakejima Island were severely damaged by a volcanic eruption in 2000. The effect of this volcanic eruption has been long lasting, and populations of this red alga still have not recovered. We investigated the effect of seabed sediment particles derived from volcanic ash on the substrate adhesion of G.?elegans spores. The analysis provides evidence that increasing amounts of sediment particles result in lower adhesion rates of G.?elegans spores, and that smaller sediment particles have a greater influence on adhesion. The amount of seabed sediment particles around Miyakejima Island was 9.3?C1815.4?mg/cm². This amount has changed greatly from year to year. The adhesion rate of G.?elegans spores in water around Miyakejima Island was 0?% at all points in 2008 and 2010, but it was estimated as 6.3?C38.6?% in 2009. These results suggest that there is significant inhibition of algal spore adhesion by seabed sediment particles derived from volcanic ash around Miyakejima Island.     

Campylobacter spp. prevalence and fluoroquinolone resistance in chicken layer farms

Chicken is a major source of human campylobacteriosis. Chicken meat originates not only from broilers but also from spent layers; however, few reports have documented the prevalence and antimicrobial resistance of Campylobacter spp. in layers in Japan. Therefore, we investigated the prevalence and antimicrobial susceptibility of Campylobacter spp. in 47 layer farms in Japan. Fecal samples were collected from the youngest and oldest flocks on the farm, and Campylobacter spp. was isolated from 46/47 (97.9%) farms. Among the C. jejuni isolates, the resistance rates to ampicillin, tetracycline, and ciprofloxacin were 29.6%, 22.2%, and 19.8%, respectively. The ciprofloxacin resistance rate (7.3%) in C. jejuni isolated from old flocks was significantly (P<0.01) lower than that in young flocks (32.5%).     

Effect of enzymes of microbial origin on in vitro digestibilities of dry matter and crude protein in soybean meal

The effects of supplementation with cellulase, xylanase, pectinase, hemicellulase, glucanase, phytase and protease of microbial origin on digestibility of crude protein (CP) and dry matter (DM) of soybean meal in vitro were examined in the present study. Changes in viscosity during in vitro digestion were also examined as an index of carbohydrate digestibility. Hemicellulase and all enzyme combinations without protease showed significant improvement of CP digestibility. Cellulase, xylanase, phytase and glucanase tended to improve CP digestibility. Dry matter digestibility was improved significantly by pectinase and all enzyme combinations. Cellulase and phytase tended to improve DM digestibility. Crude protein and DM digestibilities were the highest when all the enzymes except protease were added. Protease, cellulase, pectinase, xylanase, glucanase and hemicellulase significantly reduced viscosity, while phytase had no effect on viscosity. Viscosity was increased unexpectedly when all the enzymes were added. These results strongly suggest that a combination of carbohydrases improves the CP and DM digestibility of soybean meal while protease inhibits the actions of these enzymes. The present study also suggests that viscosity is not always a good index of digestibility. Moreover, excluding the protease from commercial crude enzyme preparations may improve digestibility.     

Response of Biochemical Markers of Bone Metabolism to Exercise Intensity in Thoroughbred Horses

We studied the response of biochemical markers of bone metabolism to exercise intensity in horses. Four horses were walked on a mechanical walker for one week (pre-exercise). Then they performed low-speed exercise on a high-speed treadmill in the first week and medium-speed exercise in the second week and high-speed exercise in the third week of training. We measured two indices of bone resorption, serum hydroxyproline concentration and the urinary deoxypyridinoline/creatinine ratio, and serum osteocalcin (OC) concentration as an index of bone formation. Both indices of bone resorption gradually decreased during the experiment. Serum OC concentration did not change in the first week but was significantly lower in the second and the third weeks compared to in the pre-exercise period and in the first week. These results suggest that the low-speed exercise decreased bone resorption but did not affect bone formation, which possibly results in increasing bone mineral content and strengthening of bones. The high-speed exercise decreased bone formation and bone resorption, i.e., bone turnover was suppressed. The low-speed exercise may be preferable for increasing bone mineral content.     

Predominant expression of growth hormone secretagogue receptor in the caudal lobe of chicken pituitary and parallel developmental increase in expression of pituitary GH and proventriculus ghrelin mRNA

To examine the involvement of ghrelin in growth hormone (GH) synthesis in the chicken pituitary, the regional distribution of GH secretagogue receptor (GHS‐R)/ghrelin receptor was investigated. Quantitative real‐time polymerase chain reaction (Q‐PCR) analysis revealed that the expression levels of GHS‐R and GH mRNA in the caudal lobe were about fourfold and sevenfold higher in the cephalic lobe of 7 day‐old chickens, respectively. Immunohistochemical analysis showed that GHS‐R immunoreactivity was more abundant in the caudal lobe than in the cephalic lobe, as was the case for GH immunoreactivity. By Q‐PCR, parallel increases were observed in the expression levels of ghrelin mRNA in the proventriculus and GH mRNA in the pituitary from embryonic day 17 to day 7 after hatching, whereas no significant change was found in the expression levels of GHS‐R mRNA in the pituitary during this period. These results suggest that proventriculus‐derived ghrelin may participate in pituitary GH synthesis by acting on its receptor during late embryonic development and the early post‐hatching period in chickens.     

Effects of added protein (bovine serum albumin) on the rate and enantiotopic selectivity of oxidative O-demethylation of methoxychlor in rat liver microsomes

The addition of bovine serum albumin (BSA) to rat liver microsomal suspensions during the O-demethylation of methoxychlor (1,1-bis(4-methoxyphenyl)-2,2,2-trichloroethane) produced a good substrate concentration-reaction rate relationship, and allowed us to determine the rate parameters for this reaction. The apparent K_m became larger when the albumin content was increased, whereas V_max was not changed. The enantiotopic selectivity of the reaction dramatically changed when the substrate concentration was increased in the absence of BSA in phenobarbital-treated rat liver microsomes.     

Change in intrarenal Ghrelin expression in immune complex-mediated glomerular disease in dogs

Ghrelin is a peptide hormone that is mainly produced by the stomach. The kidney is a major source of local ghrelin, and maintaining body fluid balance is considered a critical role of renal ghrelin. However, there are no reports on renal ghrelin in small animal medicine. The present study investigated the intrarenal localization of and change in ghrelin expression in dogs with immune complex-mediated glomerulonephritis (ICGN). Ghrelin immunoreactivity (IR) was observed in the distal tubules of normal kidneys. Ghrelin IR was weak in ICGN kidneys, and the quantitative ghrelin IR score was significantly lower in ICGN kidneys than in normal kidneys. In cases of ICGN, plasma creatinine concentrations showed a positive correlation with the ghrelin IR score.     

Randomized clinical trial to evaluate the effectiveness of enrofloxacin as a second‐line antibiotic for treatment of acute Escherichia coli mastitis

The objective of the present study was to evaluate the effectiveness of enrofloxacin (ERFX) as a second‐line antibiotic for treatment of acute Escherichia coli (E. coli) mastitis. Forty‐two cows with naturally occurring acute E. coli mastitis were enrolled. On the first day of treatment (day 0), empirically selected antibiotics (oxytetracycline: n = 32, kanamycin: n = 10) were administered. Although systemic signs improved in 10 cows (first‐line group), the signs remained unchanged or worsened in 32 cows on day 1, including two cows that were found dead. The 30 surviving cows were randomly assigned to second‐line groups constituting an ERFX group (n = 19) or a control group (n = 11) that was treated with other antibiotics. Response to each treatment was evaluated by measuring clinical signs from day 0 to day 3, subsequent quarter milk recovery, and the 60‐day survival rate. Appetite on day 3 was significantly better in the ERFX group compared to the control group. No significant differences were observed in the 60‐day survival rate or the subsequent milk recovery between the ERFX group and the control group. Thus, the use of ERFX as a second‐line antibiotic for the treatment of acute E. coli mastitis could induce a rapid appetite recovery.