Miyazaki Livestock Research Institute

Miyazaki-shi, Japan

Miyazaki Livestock Research Institute

Miyazaki-shi, Japan
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Nabenishi H.,Kitasato University | Nabenishi H.,Miyazaki Livestock Research Institute | Kitahara G.,University of MiyazakiMiyazaki | Takagi S.,Miyazaki Livestock Research Institute | And 2 more authors.
Domestic Animal Endocrinology | Year: 2017

To use plasma anti-Müllerian hormone (AMH) concentrations as early-stage markers for donor cow selection, we investigated the relationship between plasma AMH concentrations in Japanese black heifers and subsequent embryo productivity following superovulation treatment. Plasma AMH and nonesterified fatty acid (NEFA) concentrations in 6 heifers were evaluated once per month from 3 mo before successful AI for primiparity to 3 mo postpartum. Following calving, embryo collection by superovulation treatment was performed at 3- to 4-mo intervals. There were no significant differences in plasma AMH concentrations between the time points throughout the study period. There were, however, significant inter-animal differences in plasma AMH concentrations (P < 0.05). These findings suggest that plasma AMH concentrations were stable over time and individually specific. There were significant positive correlations between plasma AMH concentrations before AI and embryo productivity variables, including the number of ova/embryos (number of transferable embryos, degenerated embryos, and unfertilized oocytes) and numbers/proportions of fertilized and transferable embryos. There was no significant correlation between plasma AMH and NEFA concentrations throughout the study period. These findings reveal that plasma AMH concentrations during the rearing period can be used to predict subsequent embryo productivity following superovulation treatment, suggesting that these concentrations are useful early-stage markers for selecting donor cows. © 2017 Elsevier Inc.


Akiyama K.,Kanagawa Prefectural Livestock Industry Technical Center | Kobayashi J.,Fukushima Agricultural Technology Center | Sato Y.,Niigata Agricultural Research Institute | Sata R.,Tochigi Prefectural Dairy Farming Experiment Station | And 6 more authors.
Animal Science Journal | Year: 2010

The objective of this study was to develop an in-straw dilution method suitable for direct transfer of vitrified bovine sexed embryos. Embryo sexing was performed by molecular diagnosis. Several sexed and vitrified-warmed embryos were transferred after evaluation of morphologically embryonic survival at warming and in-straw dilution (Evaluation group). The other embryos were immediately directly transferred to recipients without first being expelled from the straws after in-straw dilution (Non-evaluation group). The pregnancy rates of vitrified sexed embryos were 38.7% and 34.8% in the Evaluation group and Non-evaluation group, respectively, which were not significantly different. The viability of lower quality embryos before vitrification tended to be lower (P = 0.087) than that of the higher quality embryos regardless of evaluating embryos after warming and in-straw dilution. The abortion rates were similar, and there was no difference between the two groups (13.9% and 12.5%, respectively). These results demonstrate that vitrified bovine sexed embryos can be vitrified and diluted by the in-straw method and that the vitrified and warmed sexed embryos can develop to term. © 2010 The Authors; Journal compilation © 2010 Japanese Society of Animal Science.


Nabenishi H.,Miyazaki Livestock Research Institute | Nabenishi H.,University of Miyazaki | Takagi S.,Miyazaki Livestock Research Institute | Kamata H.,Miyazaki Livestock Research Institute | And 4 more authors.
Molecular Reproduction and Development | Year: 2012

This study was undertaken to investigate the effects on the nuclear maturation and subsequent embryonic development of bovine oocytes exposed to heat stress (HS) when treating bovine oocytes before in vitro maturation (IVM) with 1μM cyclosporin A (CsA), an inhibitor of mitochondrial permeability transition pore opening. Mitochondrial activity, reactive oxygen species (ROS), and apoptosis levels of the oocytes were also assessed. Nuclear maturation rates of both the HS-exposed oocytes treated with or without CsA groups (HS+CsA or HS group) were significantly lower (P<0.05) than that of the control group, while the rate of the HS+CsA group was significantly higher (P<0.05) than that of the HS group. Furthermore, although the cleavage and blastocyst formation rates of the HS group were significantly lower than those of the control groups (P<0.05), both rates of the HS+CsA group recovered to the same level as those of the control group. The HS group showed a significantly higher ROS level, lower mitochondrial activity in the oocytes, and TUNEL-positive cumulus cells, but not oocytes, compared with those of the control group (P<0.05), whereas the TUNEL-positive and mitochondrial activity levels of the HS+CsA group recovered to those of the control group. These results indicate that 1μM CsA treatment before IVM may mitigate reduced mitochondrial activity, increase number of apoptotic cumulus cells under HS, and improve the nuclear maturation and developmental competence of bovine oocytes. © 2011 Wiley Periodicals, Inc.


Nabenishi H.,Miyazaki Livestock Research Institute | Nabenishi H.,University of Miyazaki | Ohta H.,Miyazaki Livestock Research Institute | Nishimoto T.,Miyazaki Livestock Research Institute | And 3 more authors.
Journal of Reproduction and Development | Year: 2011

In the present study, we investigated the relationship between the temperature-humidity index (THI) and the conception rate of lactating dairy cows in southwestern Japan, one of the hottest areas of the country. We also investigated the relationship between measurement of the vaginal temperature of lactating dairy cows as their core body temperature at one-hour intervals for 25 consecutive days in hot (August-September, n=6) and cool (January-February, n=5) periods and their THI. Furthermore, we discussed the above relationship using these vaginal temperatures, the conception rates and the THI. As a result, when the conception rates from day 2 to 0 before AI were classified into day 2, 1 and 0 groups by the six maximum THI values in each group (mTHI; <61, 61-65, 66-70, 71-75, 76-80, >80), only the conception rate for the mTHI over 80 at 1 day before AI group was significantly lower (P<0.05) than the other groups. The conception rate for days 15 to 17, but not days 19 to 22 and 30 to 35, after AI in the cows that experienced average mTHI over 80 (amTHI>80) was significantly lower (P<0.05) than that of the cows that did not experience amTHI>80. There was a significant positive correlation (P<0.01) between the mTHI and the mean daily vaginal temperature, but not during the cool period. When the mTHI reached 69, the vaginal temperature started to increase. As for the relationship between the conception rates and vaginal temperatures for all mTHI classes, in the mTHI>80 at 1 day before AI group, the vaginal temperature increased by 0.6 C from 38.7 C, resulting in a reduction of 11.6% in the conception rate from 40.5%. In conclusion, these results suggest that one of the causes of the fall in conception rate of lactating dairy cows during the summer season in southwestern Japan may be an increase in their core body temperature with a higher mTHI than the critical mTHI of 69 at 1 day before AI. © 2011 by the Society for Reproduction and Development.


Nabenishi H.,Miyazaki Livestock Research Institute | Ohta H.,University of Miyazaki | Nishimoto T.,University of Miyazaki | Morita T.,Miyazaki Livestock Research Institute | And 2 more authors.
Zygote | Year: 2012

In the present study, we investigated the effects of various concentrations of cysteine (0.0, 0.6, 1.2 and 1.8 mM) added to the maturation medium on nuclear maturation and subsequent embryonic development of bovine oocytes exposed to heat stress (HS: set at 39.5 °C for 5 h, 40.0 °C for 5 h, 40.5 °C for 6 h, and 40.0 °C for 4 h versus 38.5 °C for 20 h as the control group). This regime mimicked the circadian rhythm of the vaginal temperature of lactating dairy cows during the summer season in southwestern Japan. Moreover, we also evaluated the oocyte's reactive oxygen species (ROS) and glutathione (GSH) levels and the apoptosis levels of the oocytes and cumulus cells in the presence or absence of 1.2 mM cysteine. As a result, HS in the without-cysteine group significantly suppressed (p < 0.05) both the nuclear maturation rate up to the metaphase (M)II stage and the blastocyst formation rate compared with that of the control group. In addition, this group showed significantly higher (p < 0.05) ROS levels and significantly lower (p < 0.05) GSH levels than those of the control group. Moreover, the level of TdT-mediated dUTP nick end labelling (TUNEL)-positive cumulus cells in the HS without-cysteine group was significantly higher (p < 0.05) than that of the control group. However, the addition of 1.2 mM cysteine to the maturation medium restored not only the nuclear maturation, blastocyst formation rates and GSH contents, but also increased the ROS and TUNEL-positive levels of the cumulus cells, but not oocytes, to that of the control group. These results indicate that the addition of 1.2 mM cysteine during in vitro maturation (IVM) may alleviate the influence of heat stress for oocyte developmental competence by increasing GSH content and inhibiting the production of oocyte ROS followed by apoptosis of cumulus cells.


Suzuki K.,Japan National Agriculture and Food Research Organization | Waki M.,Japan National Agriculture and Food Research Organization | Yasuda T.,Japan National Agriculture and Food Research Organization | Fukumoto Y.,Japan National Agriculture and Food Research Organization | And 5 more authors.
Bioresource Technology | Year: 2010

Changes in swine wastewater chemical features during an activated sludge treatment process were surveyed on 11 farms, and analyzed with non-biodegradable elements, i.e., phosphorus (P), copper (Cu), and zinc (Zn). In piggery wastewater, they were linearly correlated with suspended solid (SS) concentrations and the major portion was in solid fractions. After the pretreatment step, they were removed, with 80% for total P, 85% for total Cu, and 84% for total Zn. After the activated sludge process, total P, Cu, and Zn were then removed at 83%, 96%, and 95%, respectively. Removing SS thoroughly at each step was shown to be the most important factor in preventing outflow of these elements, since there are linear correlations or a positive relationship between the removal of SS concentrations and their removal in solid form. Most of the P, Cu, and Zn in activated sludge effluent was in soluble form, and the concentrations of Cu and Zn in the effluent were low enough, while further P removal might be required. © 2010 Elsevier Ltd.


Waki M.,Japan National Agriculture and Food Research Organization | Yasuda T.,Japan National Agriculture and Food Research Organization | Suzuki K.,Japan National Agriculture and Food Research Organization | Sakai T.,Saga Prefecture Livestock Experiment Station | And 11 more authors.
Bioresource Technology | Year: 2010

This paper presents a quantitative investigation and analysis of anammox activity in sludge taken from biological swine wastewater treatment plants. An incubation experiment using a 15N tracer technique showed anammox activity in sludge taken from 6 out of 13 plants with the rate ranging from 0.0036 μmol-N2/g-VSS/h to 3.1 μmol-N2/g-VSS/h, and in a biofilm with the highest activity at 25.8 μmol-N2/g-VSS/h. It is notable that 9 out of 11 sludges in which the pH was maintained between 6.6 and 8.1 retained anammox activity, while those with either a lower or higher pH did not. Moreover, anammox-positive sludge had a significantly higher concentration of NO2- s(-) N plus NO3- s(-) N than did anammox-negative sludge. A significant difference was not observed between anammox-positive and -negative sludge regarding BOD / NH4+ s(-) N in the influent, DO concentration in aeration tanks, and the concentrations of NH4+ s(-) N, free nitric acid, and free ammonia. © 2009 Elsevier Ltd. All rights reserved.


Endo R.,University of Miyazaki | Ishii A.,University of Miyazaki | Nakanishi A.,University of Miyazaki | Nabenishi H.,University of Miyazaki | And 3 more authors.
Asian-Australasian Journal of Animal Sciences | Year: 2010

We investigated the effects of various concentrations of β-hydroxybutyrate (BHB, 0, 0.1, 1 and 10 mM), a ketone body, added to chemically-defined maturation medium with or without energy substrates (glucose, pyruvate and lactate) on nuclear maturation rates up to the metaphase stage of the second meiotic division (M-II stage). In addition, we also assessed the influence of BHB on glutathione content, sperm penetration rate and embryonic development up to the blastocyst stage of oocytes matured under the presence of these energy substrates. Nuclear maturation rates up to the M-II stage of oocytes matured with BHB in each concentration group did not show a significant increase compared with the control (0 mM) groups in both the presence and absence of energy substrates. Although glutathione contents were not significantly different in each BHB concentration group, the sperm penetration rate in the 1 mM BHB group was significantly higher (p<0.05) and the embryonic development rate of oocytes up to the blastocyst stage was significantly lower (p<0.05) than the respective values of the control groups. These results suggest that BHB added to a chemically-defined maturation medium may stimulate sperm penetration while inhibiting embryonic development of porcine oocytes.


Tsuzuki Y.,University of Miyazaki | Toyama H.,University of Miyazaki | Nabenishi H.,University of Miyazaki | Nabenishi H.,Miyazaki Livestock Research Institute | And 2 more authors.
Asian-Australasian Journal of Animal Sciences | Year: 2010

We investigated the effect of various concentrations of taurine during in vitro fertilization (IVF) on the embryonic development up to the blastocyst stage of bovine oocytes fertilized with three different Japanese Black bulls (Bull A, B and C). In vitro matured oocytes were fertilized with various concentrations of taurine (0, 1, 10, 50 and 100 mM) in the presence of 2.5 or 5.0 mM caffeine plus 25 μg/ml heparin (CH) for 6 hr or 100 μg/ml heparin (H) for 24±2 h. After IVF, the cleavage rates from the 2 to 16 cell stage determined at 3 days and the development rates up to the blastocyst stage determined at 7-8 days from the onset of IVF were assessed. Although the cleavage rates for the taurine concentration groups were not significantly increased in any of the three bulls in the CH groups, the development rates up to the blastocyst stage of the 50 mM taurine group of Bulls A and B, and of the 1 to 50 mM groups of Bull C were increased (p<0.05) compared to those of the control (0 mM taurine) groups. On the other hand, none of the bulls in the H groups showed any significant increase either in the cleavage rates or blastocyst formation rates in any taurine concentrations groups compared with those of the control groups. These results indicate that the addition of 50 mM taurine to a fertilization medium containing caffeine and heparin may stimulate embryonic development up to the blastocyst stage when fertilized with different bull semen.


PubMed | Miyazaki Livestock Research Institute
Type: Journal Article | Journal: Zygote (Cambridge, England) | Year: 2012

In the present study, we investigated the effects of various concentrations of cysteine (0.0, 0.6, 1.2 and 1.8 mM) added to the maturation medium on nuclear maturation and subsequent embryonic development of bovine oocytes exposed to heat stress (HS: set at 39.5 C for 5 h, 40.0 C for 5 h, 40.5 C for 6 h, and 40.0 C for 4 h versus 38.5 C for 20 h as the control group). This regime mimicked the circadian rhythm of the vaginal temperature of lactating dairy cows during the summer season in southwestern Japan. Moreover, we also evaluated the oocytes reactive oxygen species (ROS) and glutathione (GSH) levels and the apoptosis levels of the oocytes and cumulus cells in the presence or absence of 1.2 mM cysteine. As a result, HS in the without-cysteine group significantly suppressed (p < 0.05) both the nuclear maturation rate up to the metaphase (M)II stage and the blastocyst formation rate compared with that of the control group. In addition, this group showed significantly higher (p < 0.05) ROS levels and significantly lower (p < 0.05) GSH levels than those of the control group. Moreover, the level of TdT-mediated dUTP nick end labelling (TUNEL)-positive cumulus cells in the HS without-cysteine group was significantly higher (p < 0.05) than that of the control group. However, the addition of 1.2 mM cysteine to the maturation medium restored not only the nuclear maturation, blastocyst formation rates and GSH contents, but also increased the ROS and TUNEL-positive levels of the cumulus cells, but not oocytes, to that of the control group. These results indicate that the addition of 1.2 mM cysteine during in vitro maturation (IVM) may alleviate the influence of heat stress for oocyte developmental competence by increasing GSH content and inhibiting the production of oocyte ROS followed by apoptosis of cumulus cells.

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