Congenital malformation of the vaginal orifice,imperforate vagina,in the common marmoset (Callithrix jacchus)

The following is a report on a congenital vaginal malformation, imperforate vagina, in the common marmoset (Callithrix jacchus). This anomaly was observed for the first time in an adult female in our research colony. There was no uterine and vaginal aplasia or atresia in her grossly normal genital tract. The plasma progesterone concentration suggested that the ovarian cycle had ceased. However, this may not be related to a functional anomaly, but rather to suppressed ovulation resulting from subordination to cagemates considering the various stages of follicular development observed.     

Deleting maternal Gtl2 leads to growth enhancement and decreased expression of stem cell markers in teratoma

The distal region of mouse chromosome 12 harbors the Dlk1–Dio3 domain, is essential for normal development and encodes maternally expressed noncoding RNAs (ncRNAs), including Gtl2 as well as paternally expressed proteins.Gtl2 works as a tumor suppressor in several types of human cancer cell lines; however, whether this reflects its function in vivo is unknown. Deleting Gtl2 from the maternal allele (Gtl2^(–/+)) results in loss of expression of Gtl2 and decreased expression of downstream ncRNAs, including many miRNAs. To determine the role of ncRNAs in tumorigenesis, we induced teratomas by engrafting E6.5 embryos (wildtype or Gtl2^(–/+)) under the kidney capsule of scid mice. Some teratomas derived from the Gtl2^(–/+) embryos exhibited hypertrophic growth, suggesting that ncRNAs, including Gtl2, may act as tumor suppressors in vivo. Microarray analysis of miRNAs expressed by Gtl2^(–/+) teratomas revealed decreased expression of 28 miRNAs encoded by the Dlk1–Dio3 domain, low expression of embryonic stem cell-specific miRNAs and dysregulation of miRNAs involved in tumorigenesis. This study suggests that downregulation of ncRNAs in the Dlk1-Dio3 domain leads to enhanced teratoma growth and repression of stem cell markers.     

Examination of the microbiota of normal cow milk using MinIONTM nanopore sequencing

The aim of this study was to evaluate the microbiota of normal milk in dairy cows and their relationship with host factors, such as the age of the cow (Age), somatic cell counts in milk (SCCs), and days in milk (DIM). We investigated 48 milk samples from 22 cows with no systemic or local clinical signs using MinION^TM nanopore sequencing for a 16S rRNA gene amplicon. Bacterial richness was positively correlated with the DIM (P=0.043), and both the Shannon-Wiener Index and Simpson’s Index, which are metrics of alpha-diversity, were also significantly positively correlated with the SCC (P<0.001). The composition ratios of both Actinobacteria at the phylum level and Kocuria spp. at the genus level in the milk microbiota were significantly correlated with the SCC (P<0.001 and P<0.001, respectively). In the beta-diversity test, the one-way analysis of similarities test showed a significant difference (P=0.0051) between the low- and high-SCC groups. This study clarified that the composition of the normal milk microbiota in this herd was related to the SCC. It also raised the possibility of variations in bacterial genera in the normal milk microbiota between the low- and high-SCC groups. However, to clarify the actual condition of the milk microbiota and to elucidate the relationship with the SCC, it is necessary to perform further analyses taking into account not only the relative abundance, but also the absolute abundance of microbes.     

追肥与收获时期对水稻产量和品质影响的研究

通过不同追肥与收获处理对水稻"黄金米"品种的产量、蛋白质含量、直链淀粉含量、食味品质以及外观商品品质的影响进行了研究.结果表明,追肥时期以幼穗形成期最好;追肥量越多,产量越高.蛋白质含量越高,食口品质越差,20 Kg/hm2追肥量(纯N)最适;抽穗后41 d收获食味品质最优;追肥时期、追肥量与直链淀粉含量高低无关.     

Congenital syringohydromyelia in a crossbred (Holstein-Friesian × Japanese Black) beef calf

A 5-day-old male crossbred beef calf presented with a well-coordinated bilateral hopping gait of the hind limbs. Postmortem CT showed a poorly defined oval-shaped region at the L3–L4 spinal segments, which had high signal intensity on T2 weighted postmortem MRI images. On pathological examination, we identified a large cystic cavity filled with a large amount of cerebrospinal fluid on the cut surface of the spinal region. Histopathological examination revealed that the spinal cord parenchyma was compressed by the cystic structure, and the cystic cavity was lined with a thin layer of discrete ependymal cells, indicating syringohydromyelia. This is the first reported case of a Holstein-Friesian × Japanese Black crossbred calf with solitary syringohydromyelia. Our findings suggest that myelodysplasia with cystic cavities can be suspected by CT, without the need for MRI.     

Isolation of Molecular Markers Linked to the <Emphasis Type="Italic">Cry</Emphasis> Locus Conferring Resistance to <Emphasis Type="Italic">Cucumber mosaic cucumovirus </Emphasis>Infection in Cowpea

We previously demonstrated that cowpea [Vigna unguiculata (L.) Walp.] cultivar Kurodane-Sanjaku contains the Cry gene, which confers resistance against Cucumber mosaic cucumovirus infection. In this paper, randomly amplified polymorphic DNA (RAPD) analysis was carried out to tag the Cry locus. Bulked segregant analysis for RAPD resulted in many polymorphisms in amplified DNA patterns. Candidates were further screened using parental and/or F₂ cowpea DNAs. As a result, we obtained three RAPD markers, D13/E14-350, WA3-850 and OPE3-500, flanking the Cry locus. In addition, we amplified cowpea sequences coding for the putative nucleotide-binding site (NBS). Degenerate primers based on NBS sequences of tobacco N and Arabidopsis RPS2 disease resistance genes were used for polymerase chain reaction, and resultant products were cloned and sequenced. Among eight independent clones, cowpea resistance gene analog (CRGA) 5 showed a distinct polymorphism when used as a probe for restriction fragment length polymorphism analysis against the susceptible cowpea cultivar PI 189375 and a near-isogenic line for the Cry. Linkage analyses of these molecular markers showed that genetic distances of CRGA5, D13/E14-350, WA3-850 and OPE3-500 to the Cry locus were 0.7, 5.2, 11.5 and 24.5 cM, respectively. Received 16 December 1999/ Accepted in revised form 22 March 2000     

Distribution patterns of leptocephali in the Kuroshio–Oyashio transitional region of the western North Pacific

Leptocephalus assemblages and distribution patterns were studied in the Kuroshio–Oyashio transitional region of the western North Pacific. A total of 479 leptocephali, representing at least 21 species (types) including eight undescribed types, were collected during a cruise of the T/V Hokuho Maru from 8 to 30 May 2002. The most abundant leptocephali were the congrids Gnathophis nystromi nystromi and Gnathophis nystromi ginanago. The assemblages at each station were clustered into four groups (one group in the Kuroshio region and three in the transition zone) using the ordination and the fuzzy c‐means method based on species composition similarities between stations. Each leptocephalus species was also clustered by the same method into one of three groups. The first group had the greatest numbers of species and mainly occurred at the station group in the Kuroshio region, sharing a similar distribution to G. n. nystromi. The second group had the greatest abundance, especially in the transition zone, but contained only one species, G. n. ginanago, which also occurred at all stations. Moreover discrimination of station groups in the transition zone corresponded well with the assemblage pattern of this species group. The last species group comprised rare and low abundance species. Most leptocephali in the study area were reported from the Kuroshio upstream region, so the discrimination of leptocephali assemblages in the study area may reflect their different ecology. Furthermore, the analytical methods used in this study yielded more meaningful and clearer groups than the other usual methods, validating application of this analysis to complex areas such as the transition zone.     

Effect of summer heat environment on body temperature,estrous cycles and blood antioxidant levels in Japanese Black cow

This study investigated the effect of summer heat environment on estrous cycles and blood antioxidant levels in Japanese Black cows. A total of 13 non‐lactating Japanese Black cows (summer: 9, winter: 4) were examined. Body temperature was measured rectally and intravaginally using a thermometer and data logger, respectively. Estrous behavior was monitored using a radiotelemetric pedometer that recorded walking activity. Rectal temperatures were higher during summer than winter (P < 0.001). There was an acute increase in vaginal temperature at the onset of estrus during winter but such an increase was not observed during summer. Walking activity during estrus decreased dramatically in the summer compared to the winter. Duration of estrous cycle was longer in summer (23.4 days, P < 0.05) than winter (21.5 days), and the subsequent rise in progesterone concentrations following estrus tended to be delayed in summer. The level of thiobarbituric acid reactive substances (TBARS) in peripheral blood cells was higher during summer (P < 0.05), while the levels of superoixde dismutase (SOD), glutathione peroxidase (GPx) and glutathione were lower (P < 0.05). These results indicate that high ambient temperature during summer increases both body temperature and oxidative stress, and also reduces signs of estrus in Japanese Black cows.