Estimating the success rate of ovulation and early litter loss rate in the Japanese black bear (Ursus thibetanus japonicus) by examining the ovaries and uteri

In order to develop a method for estimating the success/failure rates of reproductive processes, especially those of ovulation and neonate nurturing, in the Japanese black bear (Ursus thibetanus japonicus), we examined offspring status, corpora lutea (CLs), placental scars (PSs) and corpora albicantia (CAs) in 159 females (0-23 years old) killed as nuisances on Honshu Island of Japan during 2001-2009. PSs were found to remain in the uterus at least until November of the year of parturition. CA detectability began to decline after September of the year of parturition. Monthly and age-specific proportions of CL-present females revealed that the post-mating season starts in August, and that the age of first ovulation is 4 years. These results indicate that the success rate of ovulation (SRO: the probability that solitary/non-lactating mature females actually succeed in ovulation) can be estimated by calculating the proportion of CL-present females among > or = 4-year-old females without PSs captured from August to November; the early litter loss rate (ELLR: the probability that parenting females lose all of their cubs [0-year-old offspring] before mating season) can be estimated by calculating the proportion of CL-present females among those with PSs and CAs captured in August or later. The estimated values of SRO and ELLR were 0.93 (62/67) and 0.27 (6/22), respectively.     

Validation of a direct time-resolved fluoroimmunoassay for progesterone in milk from dairy and beef cows

The aim of this study was to validate a direct time-resolved fluoroimmunoassay (TR-FIA) for quantifying progesterone concentrations in milk during the bovine oestrous cycle. Holstein-Friesian and suckled and non-suckled Japanese Black cows were used to demonstrate the relationship between milk and plasma progesterone concentrations and to monitor progesterone profiles in milk and plasma during the oestrous cycle. The minimum detection level of the assay was 1.53ng/mL. Progesterone concentrations in milk and plasma changed in a similar manner throughout the oestrous cycle in dairy and beef cows, and milk and plasma progesterone profiles were significantly correlated (P<0.001). The study confirmed that a direct TR-FIA can be used to monitor the oestrous cycle in cattle and to quantify progesterone concentrations in whole milk.     

Human-induced changes in the hydrology of the western United States

Observations have shown that the hydrological cycle of the western United States changed significantly over the last half of the 20th century. We present a regional, multivariable climate change detection and attribution study, using a high-resolution hydrologic model forced by global climate models, focusing on the changes that have already affected this primarily arid region with a large and growing population. The results show that up to 60% of the climate-related trends of river flow, winter air temperature, and snow pack between 1950 and 1999 are human-induced. These results are robust to perturbation of study variates and methods. They portend, in conjunction with previous work, a coming crisis in water supply for the western United States.     

Identification of a sequence-tagged site (STS) marker linked to a restorer gene for Ogura cytoplasmic male sterility in radish (Raphanus sativus L.) by non-radioactive AFLP analysis

To identify DNA markers linked to a fertility restorer (Rf) genefor Ogura cytoplasmic male sterility in radish (Raphanus sativus L.),a non-radioactive, amplified fragment length polymorphism (AFLP) analysiswas performed on bulked DNA samples from male-sterile and male-fertileradishes. Ten male-fertile and 10 male-sterile plants selected arbitrarilyfrom an F₂ population made by selfing of F₁ plant from a crossbetween a male-sterile (`MS-Gensuke') plant and a restorer (`Comet') plantwere used as material. Using 32 AFLP primer pairs, one AFLP fragment(AFLP190) which is specific to the bulked DNA samples from male-fertileF₂ plants was identified. AFLP190 was characterized by molecularcloning and nucleotide sequencing, and was converted to a sequence-taggedsite (STS) marker, STS190. A linkage analysis performed in 126individuals of two independent F₂ populations showed tight linkageof STS190 to the Rf gene. The rate of recombination between themarker and Rf was estimated to be less than 1%, making STS1901.2 cM from the gene.     

Three-dimensional structure of Hayabusa samples: origin and evolution of Itokawa regolith

Regolith particles on the asteroid Itokawa were recovered by the Hayabusa mission. Their three-dimensional (3D) structure and other properties, revealed by x-ray microtomography, provide information on regolith formation. Modal abundances of minerals, bulk density (3.4 grams per cubic centimeter), and the 3D textures indicate that the particles represent a mixture of equilibrated and less-equilibrated LL chondrite materials. Evidence for melting was not seen on any of the particles. Some particles have rounded edges. Overall, the particles' size and shape are different from those seen in particles from the lunar regolith. These features suggest that meteoroid impacts on the asteroid surface primarily form much of the regolith particle, and that seismic-induced grain motion in the smooth terrain abrades them over time.     

Expressions of tumor necrosis factor-α, its receptor I,II and receptor-associated factor 2 in the porcine corpus luteum during the estrous cycle and early pregnancy

We examined the gene and protein levels of tumor necrosis factor (TNF)-α, its receptors (types I and II, designated TNF-RI and TNF-RII, respectively), TNF receptor-associated factor 2 (TRAF2) and morphological features in the porcine corpus luteum (CL), on Days 13 and 17 (Day 0 = the last day of estrus) of the estrous cycle or of early pregnancy. Gene expression levels of TNF-α, TNF-RI, TNF-RII and TRAF2 were unaffected by the day or reproductive status. TNF-α concentration was significantly higher in the CL on Day 17 of pregnancy than on Day 13 of pregnancy and on day 17 of the estrous cycle. The TNF-RI protein level was significantly higher in the CL on Days 13 and 17 of pregnancy than those of the estrous cycle, significantly increasing on Day 17 compared with those on Day 13 in pregnancy. In relation to TNF-RII protein levels, although there were no change during pregnancy, there was a tendency (P?=?0.0524) to up-regulate as pregnancy proceeded. In estrous cycle, TNF-RII protein levels decreased significantly as luteolysis proceeded. TRAF2 protein level was significantly higher in the CL on Days 13 and 17 of pregnancy than during estrous. There were few apoptotic bodies in the CL between Days 13 and 17 of pregnancy than during esrous. There were few apoptotic bodies in the CL between Days 13 and 17 of pregnancy. The number of apoptotic bodies was much greater than the CL on Day 17 of the estrous than those of pregnancy. Thus, the TNF-α and TNF-RI and TNF-RII pathways including the TRAF2 protein, known to control of cell differentiation, tissue renewal and apoptosis, might participate in maintaining the porcine CL during early pregnancy.     

Systemic Histopathology of Infant Rats Exposed to Busulfan

Busulfan is an antineoplastic bifunctional alkylating agent. We previously reported the busulfan-induced systemic histopathological changes in fetal rats and the sequence of brain lesions in fetal and infant rats. In the present study, in order to clarify the nature and sequence of busulfan-induced systemic histopathological changes in infant rats, 6-day-old male infant rats were subcutaneously administered 20 mg/kg of busulfan and histopathologically examined at 1, 2, 4, 7 and 14 days after treatment (DAT). As a result, histopathological changes characterized by pyknosis of component cells were observed in the heart, lungs, stomach, intestines, liver, kidneys, testes, epididymides, hematopoietic and lymphoid tissues, dorsal skin and femur as well as in the brain and eyes (data not shown in this paper). Such pyknosis transiently appeared until 7 DAT with prominence at 2 and/or 4 DAT in each tissue, except for the thymus, in which pyknosis peaked at 1 DAT. Most of the pyknotic nuclei were immunohistochemically positive for cleaved caspase-3, indicating that pyknotic cells were apoptotic. Different from the reports of fetal and adult rats, apoptosis was also found in cardiomyocytes and osteoblasts in infant rats.     

Rescue In Vitro Fertilization Method for Legacy Stock of Frozen Mouse Sperm

Sperm cryopreservation has been widely adopted for maintenance of the genetically engineered mouse (GEM). The cryopreserved sperm are being exchanged among many institutes worldwide. However, the recipients are not always able to obtain high fertilization rates with the frozen sperm shipped from senders. In this study, we cryopreserved mouse sperm via various methods and performed in vitro fertilization (IVF) in which the combination of methyl-beta-cyclodextrin for sperm preincubation and reduced glutathione for insemination was used (the MBCD-GSH IVF). In addition, frozen sperm sent from the Jackson Laboratory (USA) were thawed and used for IVF in the same manner. The fertilization rates of both the sperm cryopreserved via the methods applied in some countries and the cryopreserved GEM sperm improved when used with the MBCD-GSH IVF method. Therefore, we strongly believe that the MBCD-GSH IVF method brings about relatively high fertilization rates with any strain of frozen mouse sperm.     

Rat Uterine Oxytocin Receptor and Estrogen Receptor α and β mRNA Levels are Regulated by Estrogen Through Multiple Estrogen Receptors

Estrogen action is mediated through several types of receptors (ERs), such as ERα, ERβ and putative membrane ERs. Oxytocin receptor (OTR) and ER expression levels in the rat uterus are regulated by estrogen; however, which types of ERs are involved has not been elucidated. This study examined OTR, ERα and ERβ levels in ovariectomized rats treated with 17β-estradiol (E2), an ERα agonist (PPT), an ERβ agonist (DPN) or estren (Es). E2 and PPT increased OTR mRNA levels and decreased ERα and ERβ mRNA levels 3 and 6 h posttreatment. DPN decreased ERα and ERβ mRNA levels at 3 and 6 h, while OTR mRNA levels increased at 3 h and decreased at 6 h. OTR mRNA levels increased 3 h after the Es treatment and then declined until 6 h. ERα and ERβ mRNA levels decreased by 3 h and remained low until 6 h posttreatment with Es. The ER antagonist ICI182,780 (ICI) suppressed the increases in OTR mRNA levels induced 3 h after the Es treatment. However, ICI and tamoxifen (Tam) had no significant effect on ERα and ERβ mRNA levels in the Es-treated or vehicle-treated group. In intact rats, proestrus-associated increases in OTR mRNA levels were antagonized by both ICI and Tam. However, decreases in ERα and ERβ mRNA levels were not antagonized by Tam and ICI, respectively. Therefore, uterine OTR gene expression is upregulated by estrogen through the classical nuclear (or non-nuclear) ERs, ERα and ERβ, while the levels of these ERs are downregulated by estrogen through multiple pathways including Es-sensitive nonclassical ERs.     

Phosphorus budget in shrimp aquaculture pond with mangrove enclosure and aquaculture performance

ABSTRACT:   An experiment in which water was circulated between shrimp aquaculture ponds stocked with 10 000 or 20 000 PL-15 stage Penaeus monodon , and mangrove enclosures each planted with 476 Rhizophora mucronata per enclosure, was carried out at the Samut Songkhram Coastal Aquatic Research Station, Faculty of Fisheries, Kasetsart University, Thailand. Shrimp survival rate was significantly higher ( P  < 0.001, Fisher's exact test) in ponds where 10 000 larvae was stocked and water was exchanged with the mangrove enclosure, compared with the control pond with no water exchange, over the 136 day experimental period. Phosphorus transport to the mangrove enclosure was estimated to be 0.41 kgP and 0.18 kgP over the experimental period and change in phosphorus content in mud was reduced there compared with the control pond. A load reduction effect to the environment was confirmed in this aquaculture system with mangrove enclosure compared with the phosphorus budget in the control pond, and 6.2 or 8.9 ha of mangrove area was estimated to be required by 1 ha shrimp ponds to fully process the phosphorus.