Effect of aging in adult Monochamus alternatus (Coleoptera: Cerambycidae) on the susceptibility of the beetle to Beauveria bassiana (Ascomycota: Hypocreales)

To clarify the effect of aging in adult Monochamus alternatus on the susceptibility of the beetle to Beauveria bassiana, we inoculated the fungus into adult beetles 0, 3, 7, 14, and 28 days after emergence. The number of days from B. bassiana inoculation to M. alternatus death increased with the number of days from beetle emergence to inoculation up to 14 days after emergence. This indicated that the susceptibility of adult beetles to the fungus decreased with aging. However, B. bassiana-inoculated beetles 28 days after emergence died earlier after inoculation than those inoculated with the fungus 14 days after emergence; i.e., the beetle’s susceptibility to the fungus increased again. We considered this phenomenon to be the result of senescence of adult beetles. We concluded that the susceptibility of M. alternatus to B. bassiana decreased first and then increased again with aging.     

Studies on the regulation of expression of luteinizing hormone receptor in the ovary and the mechanism of follicular cyst formation in ruminants

In the series of studies, changes of expression and regulation of luteinizing hormone (LH) receptor in the ovary of domestic ruminants were examined. Furthermore, mechanisms of formation of follicular cysts in domestic ruminants, caused by stress and so on, were endocrinologically elucidated. Results of the studies provide the following conclusions. (1) The quantity of LH receptor in the bovine antral follicles increases rapidly in the latter stage of its development. (2) The quantity of LH receptor and its mRNA in the bovine and caprine corpus luteum increase during their developments. The increase of the receptor in the caprine luteal development is regulated by LH through the receptor mRNA level. (3) At least, three splice variants of LH receptor mRNA exist in the bovine luteal tissue and the variant receptors are expressed at different cellular sites according to its structure. (4) Intracellular consecutive cysteine residues of LH receptor are palmitoylated and thereby inhibit internalization of the receptor. (5) As a mechanism of the bovine follicular cyst caused by stress, it is suggested that increased secretions of progesterone and cortisol from the adrenal gland exert inhibitory effects on the hypothalamus and follicle, respectively, and subsequently LH and FSH surges are blocked, then finally ovulation is suppressed and the follicle becomes cystic.     

Effect of soil physical properties on soybean nodulation and N2 fixation at the early growth stage in heavy soil field in Hachirougata Polder,Japan

We studied the effect of the soil physical properties on soybean nodulation and N₂ fixation in the heavy soil of an upland field (UF) and an upland field converted from a paddy field (UCPF) in the Hachirougata polder, Japan. Seeds of the soybean cultivar Ryuho were sown in each field with or without inoculation of Bradyrhizobium japonicum A1017. The soybean plants were sampled at 35 (V3) and 65 (Rl) d after sowing (DAS), and then nodulation and the percentage of N derived from N₂ fixation in the xylem sap were determined. The soil physical properties were different between UF and UCPF, especially the air permeability and soil water regime. Nodule growth was restricted in UCPF irrespective of rhizobial inoculation, though rhizobial infection was not inhibited by the unfavorable soil physical conditions. Soybean plant growth was closely related to the nodule mass and N₂ fixation activity, and the inoculation of a superior rhizobium strain was effective only at 35 DAS. These results indicate that soybean nodulation and N₂ fixation was considerably affected by the physical properties of heavy soil, and that it is important to maintain the N₂ fixation activity and inoculate the soybean plants with a superior rhizobium strain at a later growth stage in order to increase soybean production in heavy soil fields.     

Adenomyosis with severe inflammation in the uterine cervix in a dog

A dog with purulent vulval discharge was found to have many cysts containing purulent mucus in the uterine cervix. The uterine horns did not contain any pus. Histological examination revealed a cervical adenomyosis infiltrated by many neutrophils. After an ovariohysterectomy including the whole cervix, the dog recovered well.     

Long-term prevention of estrus in the bitch and queen using chlormadinone acetate

Estrus was prevented with weekly oral administration of 2 mg chlormadinone acetate for 2.0 to 9.8 y in bitches and queens. Abnormalities, including mammary or uterine disorders, or both, were noted in 7 out of 14 bitches and 9 out of 24 queens during this long-term treatment.     

Prevalence,O-genotype and Shiga toxin (Stx) 2 subtype of Stx-producing Escherichia coli strains isolated from Argentinean beef cattle

The aims of this study were to investigate prevalence, O-genotype, and virulence gene profile including Shiga toxin (Stx) 2 gene-subtype of Stx-producing Escherichia coli (STEC) in beef cattle from the Bahía Blanca in Argentina. Rectal swabs were collected from 283 beef cattle in 2012. stx genes were detected in 90 (32%) out of the 283 rectal swabs by stx gene-specific PCR assay. The positive cases were 13 with stx1, 58 with stx2, and 19 with both stx1 and stx2. Among 90 stx gene-positive samples, 45 STEC strains were isolated, which included 3 stx1, 34 stx2, and eight stx1 and stx2 genes positive isolates. O-genotyping grouped 45 STEC strains into 19 different O-genotypes such as Og8, Og145, Og171, Og185 (4 from each), Og22, Og153, Og157 (3 from each) and others. Various stx2 gene-subtypes were identified in 42 STEC strains: 13 positive cases for stx2a, 11 for stx2c, 3 for stx2g, 10 for stx2a and stx2d, 4 for stx2a and stx2c, and 1 for stx2b, stx2c and stx2g. efaI gene, generally prevalent in clinical strains, was detected in relatively high in the STEC strains. These data suggest that stx2a and stx2c were distributed not only in O145 and O157 but also in minor O-genotypes of STEC in Argentina.     

Partitioning of photosynthates originating from bent shoots in the arching and high-rack culture systems of cut rose production

The arching and high-rack culture systems were developed and patented by Japanese rose growers. Both culture systems have bent canopies (lower bent shoots). In the arching culture system, shoots sprouting from the crown are harvested as cut flowers. However, the high-rack culture system also has a bent canopy originating from the mother stem (upper bent shoots) and flower stems sprout and is harvested at the top of each mother stem. Partitioning of photosynthates originating from bent shoots in arching and high-rack culture systems of rose production was investigated to elucidate how carbohydrates are re-allocated from the bent shoots in different culture systems of roses. At the flowering stage in both culture systems, 50–70% of ¹³C-photosynthates originated from bent shoots were exported to other parts within 72 h after ¹³CO₂ feeding to the bent shoot. In the arching culture system, photosynthates from lower bent shoots were partitioned mainly to the roots and crown. Similarly, in the high-rack culture system, between 71 and 86% of the exported carbon from the bent shoots were allocated to below the point of bending (roots + crown + mother stems) and only 9–28% was allocated to flowering shoots above the point of bending. In both culture systems, photosynthate translocation from the lower bent shoot directly to flowers was low. Accordingly, bent shoots in rose plants acted as a source of photosynthates, independent of culture system. The height of the bent shoots determined for a great deal in the re-allocation of the photosynthates, and provides a partial explanation for difference in production of cut roses.     

Quantitative analyses of insulin-like peptide 3 and sex steroid hormones in dominant follicles and corpora lutea during the estrus cycle and in follicular cysts in beef heifers

Insulin-like peptide 3 (INSL3) and sex steroids were measured in bovine dominant follicles and corpora lutea during the estrus cycle and in follicular cysts. Paired ovaries from beef heifers (n = 47) were classified, by their morphological features, either into four stages of the estrus cycle (Day 1 = day of ovulation, Day 20 = day of estrus) as Stage I (Days 1–4; n = 8), Stage II (Days 5–10; n = 10), Stage III (Days 11–17; n = 8), and Stage IV (Days 18–20; n = 11) or follicular cystic (n = 10). Cysts (n = 15) were subdivided into estrogen-active (n = 7) and estrogen-inactive (n = 8) cysts. INSL3, testosterone, and estradiol-17β concentrations in the dominant follicular fluid of Stage IV were higher than those in Stages II and III (P < 0.05). INSL3 concentrations in the cystic fluid were similar to those in dominant follicles at Stage IV, whereas testosterone and estradiol-17β concentrations were lower in cysts (P < 0.05). INSL3 content per estrogen-inactive cyst was higher than that of Stage IV (P < 0.05). INSL3 and progesterone concentrations in luteal tissue and contents per corpus luteum were higher in Stages II and III (P < 0.05). In conclusion, INSL3 secretion in bovine dominant follicles increased with maturation. Follicular cysts may retain the production of INSL3 during their formation but tend to lose the capacity for testosterone secretion. Estrogen-inactive cysts subjected to advanced atresia may accumulate more INSL3. INSL3 production in bovine corpora lutea is enhanced during maturation.     

Identification of a novel glycoside, leptosin, as a chemical marker of manuka honey

As a preliminary study, we have found that honey from manuka (Leptospermum scoparium) in New Zealand inhibits myeloperoxidase (MPO) activity. In this study, using a chromatographic technique, we isolated two active compounds for MPO-inhibition from manuka honey. One is methyl syringate (MSYR), and the other was identified as a novel glycoside of MSYR, methyl syringate 4-O-β-D-gentiobiose, which has been named "leptosin" after the genus Leptospermum . The amount of the glycoside ranged from 0.2 to 1.2 μmol/g honey. Leptosin was only found in honeys from the Oceania region, and abundantly in manuka honey including jelly bush honey from Leptospermum polygalifolium in Australia. Therefore, leptosin may be a good chemical marker for manuka honey. Interestingly, the concentration of leptosin in manuka honey was positively correlated with the unique manuka factor (UMF) value, which is expressed as phenol equivalents of its bactericidal activity.     

Inhibitory effects of CIDR-based ovulation-synchronization protocols on uterine PGF2alpha secretion at the following luteal phase in early postpartum non-cycling beef cows

We investigated whether CIDR-based ovulation-synchronization protocols inhibit secretion of prostaglandin (PG) F2alpha from the uterus in the following luteal phase in non-cycling beef cows. Ten early (a month) postpartum non-cycling Japanese Black beef cows were treated with (1) Ovsynch (GnRH analogue on Day 0, PGF2alpha analogue on Day 7, and GnRH analogue on Day 9; n=3), (2) Ovsynch+CIDR (Ovsynch protocol plus a CIDR for 7 days from Day 0; n=4), or (3) estradiol benzoate (EB) Ovsynch+CIDR (EB on Day 0 in lieu of the first GnRH treatment followed by the Ovsynch+CIDR protocol; n=3). An oxytocin challenge was administered on Day 24 to examine uterine PGF2alpha secretion. Plasma concentrations of 13,14-dihydro-15-keto- PGF2alpha were lower at 30-120 min after oxytocin administration in the Ovsynch+CIDR group and 75 min after administration in the EB Ovsynch+CIDR group than in the Ovsynch group (P<0.05). Plasma progesterone concentrations were higher from Days 1 to 7 in the Ovsynch+CIDR group and from Days 1 to 5 in the EB Ovsynch+CIDR group than in the Ovsynch group (P<0.05). The progesterone concentrations were higher on Days 27 and 29 in both CIDR-treated groups than in the Ovsynch group (P<0.05). In conclusion, in non-cycling beef cows, CIDR-based ovulation-synchronization protocols inhibit uterine PGF2alpha secretion in the following luteal phase and prevent premature luteolysis as is seen with the Ovsynch protocol.