Comparison of Ammonium Deposition Flux at Roadside and at an Agricultural Area for Long-Term Monitoring: Emission of Ammonia from Vehicles

To understand the effect of the NH₃ emissions from vehicles, the NH₄ ⁺ bulk deposition and concentrations of gaseous NH₃ and particulate NH₄ ⁺ were measured at two sites in Saitama prefecture, Japan, one at the roadside of an arterial road (Kounosu), and the other in an agricultural area (Kisai). We observed that the NH₄ ⁺ bulk deposition and NH₃ concentration were significantly increased in Kounosu; the effect of NH₃ emissions from vehicles was confirmed. NOx was a primary pollutant mainly emitted by vehicle exhaust in the vicinity of arterial roads, and the relationship between NO _x and sum of gaseous NH₃ and particulate NH₄ ⁺ (T-NH₄ ⁺) was examined. The [T-NH₄ ⁺/NO _x ] ratios in Kounosu ranged from 0.08 to 0.23 (average 0.15), and in Kisai they ranged from 0.16 to 0.67 (average 0.39). In Kounosu, the effect of vehicle exhaust was great, but seasonal variation was small. The contribution ratio of NH₃ from vehicle emissions increased at low temperatures, while that from the non-vehicle emissions increased at high temperatures.     

Progesterone Profiles in the Caudal Vena Cava and Jugular Vein in Response to Pulsatile Luteinizing Hormone Stimulation Induced by GnRH Treatment During the Mid-luteal Phase in Lactating Dairy Cows

The aim of this study was to examine whether increased frequency of luteinizing hormone (LH) pulses influences luteal progesterone (P₄) secretion by measuring progesterone concentrations at the secreted (caudal vena cava) and circulating levels (jugular vein) in lactating dairy cows. Cows received six intravenous administrations of 2.5 μg of GnRH (gonadorelin acetate, n=4) or 2 ml saline (n=3) at 1-h intervals on 12.4 ± 0.4 (mean ± SE) days after ovulation. Blood samples were collected from the caudal vena cava and jugular vein every 12 min for 12 h (6 h before and after treatment). During the 6 h after treatment, frequency of LH pulses (5.3 ± 0.3 and 3.0 ± 0.0 pulses/6 h) and mean LH concentration (0.50 ± 0.06 and 0.38 ± 0.05 ng/ml) were greater (P<0.05) in GnRH-treated cows than in saline-treated cows. Mean P₄ concentration and amplitude of P₄ pulses in the caudal vena cava during the 6 h after treatment were greater (P<0.05) in GnRH-treated cows than in saline-treated cows, but the frequency of P₄ pulses was not different between the groups. Mean P₄ concentration in the jugular vein during the 6 h after treatment was also higher (P<0.05) in GnRH-treated cows than in saline-treated cows (7.0 ± 1.3 and 5.4 ± 0.9 ng/ml). These results indicate that the increased frequency of LH pulses stimulates progesterone secretion from the functional corpus luteum and brings about higher P₄ concentrations in the circulating blood in lactating dairy cows.     

Changes in Plasma Progesterone Levels in the Caudal Vena Cava and the Jugular Vein and Luteinizing Hormone Secretion Pattern After Feeding in Lactating and Non-lactating Dairy Cows

The present study was designed to assess progesterone profiles at the secreted (caudal vena cava) and circulating levels (jugular vein) and luteinizing hormone (LH) secretion pattern in lactating and non-lactating cows with reference to feeding. Four lactating and four non-lactating cycling Holstein cows were examined. Blood samples were collected simultaneously from the caudal vena cava (via a catheter inserted from the coccygeal vein) and the jugular vein every 15 min for 12 h (0500–1700 h) during the functional luteal phase. Cows were fed 50% of the daily diet 6 h after the start of blood sampling. During the 12-h sampling period, mean progesterone concentrations in the caudal vena cava did not differ between lactating and non-lactating cows (49.0 ± 2.9 and 53.3 ± 3.7 ng/ml; mean ± SE), whereas mean progesterone concentrations in the jugular vein in lactating cows were higher than those in non-lactating cows (6.4 ± 0.1 and 5.6 ± 0.1 ng/ml, P < 0.001). Lactating cows had a higher frequency of LH pulses than non-lactating cows (7.0 ± 0.7 and 4.3 ± 0.9 pulses/12 h, P<0.05). The influence of feeding was not observed on LH profiles but was observed on progesterone profiles in both veins. Progesterone concentrations in the caudal vena cava increased after feeding in both groups. Progesterone concentrations in the jugular vein decreased after feeding in lactating cows but not in non-lactating cows. These results indicate the difference in feeding-related changes in progesterone dynamics between lactating and non-lactating cows.     

Differential Effects of Continuous Exposure to the Investigational Metastin/Kisspeptin Analog TAK-683 on Pulsatile and Surge Mode Secretion of Luteinizing Hormone in Ovariectomized Goats

The aim of the present study was to determine if the estradiol-induced luteinizing hormone (LH) surge is influenced by the constant exposure to TAK-683, an investigational metastin/kisspeptin analog, that had been established to depress the pulsatile gonadotropin-releasing hormone (GnRH) and LH secretion in goats. Ovariectomized goats subcutaneously received TAK-683 (TAK-683 group, n=6) or vehicle (control group, n=6) constantly via subcutaneous implantation of an osmotic pump. Five days after the start of the treatment, estradiol was infused intravenously in both groups to evaluate the effects on the LH surge. Blood samples were collected at 6-min intervals for 4 h prior to the initiation of either the TAK-683 treatment or the estradiol infusion, to determine the profiles of pulsatile LH secretion. They were also collected at 2-h intervals from –4 h to 32 h after the start of estradiol infusion for analysis of LH surges. The frequency and mean concentrations of LH pulses in the TAK-683 group were remarkably suppressed 5 days after the start of TAK-683 treatment compared with those of the control group (P<0.05). On the other hand, a clear LH surge was observed in all animals of both groups. There were no significant differences in the LH concentrations for surge peak and the peak time of the LH surge between the TAK-683 and control groups. These findings suggest that the effects of continuous exposure to kisspeptin or its analog on the mechanism(s) that regulates the pulsatile and surge mode secretion of GnRH/LH are different in goats.     

Evaluation of dry matter production and yield in early-sown wheat using near-isogenic lines for the vernalization locus Vrn-D1

ABSTRACT

Wheat (Triticum aestivum L.) grain yield is predicted to decrease in the future because of an increase in air temperature globally. To clarify the effects of the vernalization response gene in wheat to warmer winters, we compared dry matter production and grain yield between spring wheat ‘Asakazekomugi’ and its winter-type near-isogenic line (NIL) carrying different alleles of the vernalization response gene Vrn-D1 under early-, standard-, and late-sowing conditions. Under early-sowing conditions, dry matter production of the NIL carrying the winter allele of Vrn-D1, named Asa (Vrn-D1b), exceeded that of ‘Asakazekomugi’ from mid-March (after stem elongation in Asa (Vrn-D1b)) when the temperatures rose. Tiller number and leaf area index under early-sowing conditions were consistently higher in Asa (Vrn-D1b) than in ‘Asakazekomugi’ from mid-March onward. It was suggested that the early-sown ‘Asakazekomugi’ could not effectively absorb solar radiation to produce dry matter because of the acceleration of stem elongation caused by the Vrn-D1 gene during the cold season. The grain yield of Asa (Vrn-D1b) with early sowing was higher than with standard sowing. In contrast, the grain yield of ‘Asakazekomugi’ was lower in the early-sown crop than in the crop sown at the standard date. These results suggested that the higher grain yield of Asa (Vrn-D1b) than that of ‘Asakazekomugi’ under early-sown conditions could be due to Asa (Vrn-D1b) maintaining high dry matter production after the jointing stage by suppressing acceleration of growth caused by warm conditions after sowing.     

Comparison of productive and reproductive performance and hair cortisol levels between Brown Swiss cross‐bred and Holstein cows housed in the same barn

The productive and reproductive characteristics of Brown Swiss (B) cross‐bred cows were investigated by comparing with those of Holstein (H) cows housed in the same barn. Additionally, their hair cortisol levels were analyzed to evaluate the extent of stress experienced during dry and lactation periods. B cross‐bred cows had lower milk yields and higher milk fat rates than H cows. Reproductive records showed that days from parturition to first artificial insemination (AI) in B cross‐bred (n = 16) and H (n = 27) cows were not significantly different, but conception rate at first AI of B cross‐bred cows tended to be higher than that of H cows. Percentage of B cross‐bred cows that resumed ovarian cyclic activity within 45 days after parturition was higher than that of H cows (6/6 (100%) and 5/11 (45.5%), P < 0.05), and B cross‐bred cows had higher body condition scores at that time. Hair cortisol level at 60 to 90 days after parturition in H cows increased significantly compared with in the dry period, and it was higher than that of B cows during the same period. These results suggest that B cross‐bred cows experience less metabolic stress during early lactation, which may result in earlier resumption of reproductive function.     

Interactions of Salinity Stress and Flower Thinning on Tomato Growth,Yield, and Water Use Efficiency

This study was conducted to investigate the effects of salinity stress and flower number on growth, yield, water use efficiency (WUE), and fruit quality of cherry tomatoes cultivated under soilless conditions. The experiment was conducted in a plastic house (5-m wide × 11-m long) located in Gifu University. The seedlings were transplanted in a randomized complete block design with six plants per treatment (NT1 and ST1 were with four plants), giving a total of 44 plants in 22 pots (two plants per pot). Two different salinity levels [no-salinity and salinity with electrical conductivity: 0.8 and 3.0 dS m^?1, respectively] and four flower number treatments (8, 13, 18, and free per truss) were investigated in the experiment. The results showed that salinity stress negatively affected tomato growth, yield, and marketable yield, but improved tomato fruit quality. The number of flowers had no effect on tomato growth variables and WUE, but the yield significantly increased with increasing flower number. However, the fruit quality was decreased with increased flower number. A reasonable control for fruit load can increase marketable yield in commercial cultivation. Under salinity stress conditions, properly increasing the number of flowers can avoid yield reduction.     

Interactive Influences of Salinity Stress and Leaf Thinning on the Growth,Yield, Water use Efficiency,and Fruit Quality of Cherry Tomatoes

This research has experimentally investigated the interactive influences of salinity stress and leaf thinning on the growth, yield, water use efficiency, and fruit quality of cherry tomatoes cultivated under soilless conditions. The experiment was conducted in a plastic house (width of 5 m and length of 11 m) located in Gifu University. The seedlings were transplanted in a randomized complete block design with six plants per treatment, and a total of 36 plants in 18 pots (two plants per pot). The experiment received salinity treatment (no-salinity and salinity with electrical conductivity (EC) of 0.8 dS m^?1 and 3.0 dS m^?1, respectively) and leaf thinning treatment (no leaf thinning, basal leaf thinning and intersegment leaf thinning except the closest two). The experimental results showed that salinity stress negatively affected the growth, yield, marketable yield and water use efficiency of cherry tomatoes, but positively affected the fruit quality. Basal leaf removal significantly decreased the biomass, chlorophyll, and yield but significantly improved the fruit quality; that basal leaf removal coupled with salinity stress showed no influence on plant growth, but reduced the yield and greatly improved the fruit quality. Besides, tender leaves around truss removal significantly decreased the biomass, chlorophyll, yield, and water consumption, but improved the fruit quality; that tender leaves around truss removal coupled with salinity stress greatly decreased the biomass, chlorophyll, yield, and water consumption, but significantly improved the fruit quality.     

Zoogeographical barriers causing discontinuous osteometrical variations in the northern treeshrew skulls

Morphological variation of the skull was examined in the northern treeshrew (Tupaia belangeri) from various localities across Southeast Asia. Through a multivariate analysis, the treeshrews from South Vietnam exhibited distinct morphological characteristics compared to other populations from Thailand and Laos, and Malaysia. The plots of the specimens of North Vietnam are not randomly mixed with Thailand plots segregation in the scatteregrams of canonical discriminant analysis. Since the skulls of the population from North Vietnam were morphologically similar to those form central Laos and northern and northeastern Thailand, the zoogeographical barrier effect of Mekong River was not clearly confirmed. The population of the Kanchanaburi in western Thailand is clearly smaller in size compared to the other populations. The southern border of the distribution of this species is determined by the Isthmus of Kra or Kangar-Pattani Line. In the northern treeshrew, which is distributed from southern China to Bangladesh and southern Thailand, we have detected osteometrical geographical variation driven by geography. These results indicate that the skull morphology in the Tupaia glis-belangeri complex distinctively differs in South Vietnam, western Thailand, and southern Thailand. The zoogeographical barrier and factor separating these districts are expected to clarify in the future.