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131.
Masahiro Osada Hitomi Iwabuchi Toru Aoki Kika Sasaki Hitoshi Ushijima Takeyuki Ozawa 《Animal Science Journal》2019,90(4):597-603
Artificial insemination using sex‐sorted semen is employed to efficiently increase the number of female dairy calves born. Previous studies have determined that using sex‐sorted semen is beneficial to improve the management, but the mechanism by which it increases cattle numbers through objective indices of breeding remains unclear. This study focused on a Brown Swiss cattle herd in which frozen female sex‐sorted semen was systematically employed to increase the number of cattle. We analyzed the correlation between the increase in the number of cattle and the screening accuracy of sex‐sorted semen, measuring indices such as pregnancy rate and birth rate of female calves. Study revealed that: (1) production cost for female calves is influenced by the pregnancy rate, rate of female calves, and using sex‐sorted semen is less expensive than using nonsorted semen; (2) improvements in screening accuracy nearly doubled the number of cows and tripled the number of heifers in 5 years; and (3) use of sex‐sorted semen improved milk quality. The pregnancy rate was lower when sex‐sorted semen was used, but the birth rate of heifers was improved. Results suggest that artificial insemination using sex‐sorted semen is beneficial because it economically produces offspring to increase the herd. 相似文献
132.
SUMMARY: Genetic correlations between racing times on track type (turf and dirt), and at racing distances on turf (1200 m, 1400 m, 1600 m, 1800 m, and/or 2000 m) and dirt (1000 m, 1200 m, 1400 m, 1600 m, 1700 m, and/or 1800 m) tracks, were estimated in Thoroughbred horses. (Co)variance components were estimated using multiple-trait derivative-free restricted maximum likelihood (MTDFREML). The data used were collected by the Japan Racing Association from 1992 to 1993. The generation 2 pedigree information was preferable for (co)variance estimates. The genetic correlations between racing times on turf and dirt tracks ranged from 0.69 to 0.31 (average 0.51). The genetic correlations between racing distances ranged from 0.68 to 1.00 (average 0.85) and from 0.53 to 1.00 (average 0.88) on turf and dirt tracks, respectively. These results suggest that the racing time per 100 m can be used for horse genetic evaluation within one track type. ZUSAMMENFASSUNG: Sch?tzung genetischer Korrelationen zwischen Rennzeiten von Vollblüternüber verschiednen Distanzen mittels restringierter Genetische Korrelationen zwischen Rennzeiten auf Rasen- und Erdbahnen, Renndistanzen auf Rasen- (1200, 1400, 1600, 1800 und 2000 m) und Erdbahnen (1000, 1200, 1400, 1600, 1700 und 2000 m) wurden für Vollblüter gesch?tzt. (Co)Varianzkomponenten wurden mittels Mehr-Merkmal Ableitungsfreier Restringierter Maximum Likelihood (MTDFREML) gesch?tzt. Die Unterlagen wurden von der Japanischen Renn Vereinigung 1992 und 1993 gesammelt. Generation 2 Abstammungsinformation war für die Co-Varianzsch?tzung günstig. Genetische Korrelationen zwischen Rennzeiten auf Rasen und auf Erdbahnen waren zwischen 0.69 und 0.31 (Durchschnitt 0.51), jene zwischen Distanzen zwischen 0.68 und 1.00 (Durchschnitt 0.85) und zwischen 0.53 und 1.00 (Durchschnitt 0.88) auf Rasen und Erdbahnen. Die Ergebnisse zeigen, da? Rennzeit per 100 m zur Bewertung der Pferde geeignet ist. 相似文献
133.
We investigated the environmental factors in Japan, including meteorological conditions, on the fertility of a European cattle breed, Holstein–Friesian, by examining conception rates in different regions. First artificial insemination and associated conception details were recorded for 69,952 Holstein female cattle. In general, meteorological conditions vary considerably according to latitude in Japanese islands. Conception rates were higher in the Northern (above 37°N) than the Southern (below 37°N) region (61.3% vs. 53.3%). All the factors analyzed in the statistical model, including insemination year, region, month, AI technician, service sire and interaction between region and month, had significant effects on the conception rate. In the Southern region, conception rates were lower in the summer months (average temperature, 27.8 °C, and maximum temperature, 32.3 °C). However, this seasonal decline was not observed in the Northern region (average temperature, 23.7 °C, and maximum temperature, 28.4 °C). Regression analysis of conception rate in relation to temperature showed highly significant negative regression coefficients (− 0.66 to − 0.63% per °C; p < 0.001) in the Southern region, but non-significant coefficients in the Northern region. Humidity had a minimal effect on conception rate in both regions. Our data collectively suggest that 37°N latitude is a threshold that affects Holstein–Friesian conception rates in Japan. 相似文献
134.
The rheological properties of cooked white salted noodles made from eight wheat cultivars with varied amylose content were analyzed at small and large deformation. Their dynamic shear viscoelasticity was measured using a rheometer with parallel plate geometry. Compressive force and creep‐recovery curves were measured using various probes and sample shapes. Noodles with lower amylose content showed a lower storage shear modulus (G′) and a higher frequency dependence of G′. The G′ values of noodles were highly correlated with amylose content in wheat flour and with G′ values of 30 and 40% starch gels. Remarkable differences in the characteristics of creep‐recovery curves were observed between cultivars. The difference in amylose content in wheat flour reflected the creep‐recovery properties of noodles. A negative correlation was demonstrated between amylose content and both maximum creep and recovery compliance. The compressive force required for 20, 50, 80, and 95% strains was compared. At 20 and 50% strain, noodles made from lower amylose wheat flour showed lower compressive force. Noodles of waxy wheat had a higher compressive force than nonwaxy noodles when the strain was >80%, indicating the waxy wheat noodles are soft but difficult to completely cut through. 相似文献
135.
K Sato S S Sasaki Y Goda T Yamada O Nunomura K Ishikawa T Maitani 《Journal of agricultural and food chemistry》1999,47(11):4665-4668
The fruits of Capsicum annuum L. are used worldwide as chili peppers and in folk medicines. The pungent components of C. annuum, which are irritants, are called capsaicinoids (CAPS), and the most abundant components are capsaicin, dihydrocapsaicin, and nordihydrocapsaicin. To analyze CAPS in the placentas of Capsicum fruits rapidly and safely, we used a directly connected system of supercritical fluid extraction and supercritical fluid chromatography (SFE/SFC). As a column for SFE/SFC, only a silica-type column was found to be suitable. The CAPS contents in placentas of C. annuum cv. Jalapeno (hot type) and C. annuum cv. Shishitoh (less-hot type) determined by the SFE/SFC method agreed well with those in the range of 0-13.81 mg g(-1) fr. wt determined by the usual extraction-HPLC method. The SFE/SFC method has the advantages of no need for pretreatment and no (or minimal) need for organic solvents. We conclude that this method is useful as a rapid (20 min) and safe screening test for the pungency of various Capsicum fruits. 相似文献
136.
H Endo T Makita M Sasaki K Arishima M Yamamoto Y Hayashi 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(8):903-907
Since we have clarified the manipulation mechanism using the radial sesamoid (RS) in the giant panda (Ailuropoda melanoleuca), our aim in this study is to examine the position, shape and function of the RS morphologically, and to observe the attachment to the RS of the M. abductor pollicis longus and the M. opponens pollicis in the other Ursidae species. So, we focused on the carpus and manus of the polar bear (Ursus maritimus) and the brown bear (Ursus arctos) in this study. The RS was tightly articulated to the radial carpal, and could not adduct-abduct independently of the radial carpal. The M. abductor pollicis longus tendon and the M. opponens pollicis belly were attached to the RS, independently. In the polar bear, the deep concave and the flat surface were confirmed in attachment area for these two muscles. The morphological relationship between the RS and the M. abductor pollicis longus and the M. opponens pollicis in the two species of bears were essentially consistent with that in the giant panda. It also demonstrated that the manipulation mechanism of the giant panda has been completely based on the functional relationship between the small RS, and the M. abductor pollicis longus and the M. opponens pollicis in Ursidae species. 相似文献
137.
M Sasaki Y Hayashi H Koie Y Yamaya J Kimura D Manglai S Kawashima H Endo M Yamamoto 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(9):1019-1022
The domestic horse (Equus caballus) have the large symmetrical guttural pouches (the auditory tube diverticulum) formed by saccate bulge of the auditory tube. In this study, CT examination was carried out in the head of Przewalski's horse (Equus przewalskii), the only true wild horse living at present. As results of the examination, Przewalski's horse possessed the large symmetrical guttural pouches divided into medial and lateral compartments by the stylohyoid bone. Moreover, the right and left guttural pouches meet each other at the median part to form a thin septum. As CT sections get close to the part of the occipital condyle, the lateral compartment disappeared, and the medial compartment gradually became small toward the base of the skull. These results indicate that the nuchal-basal part of the medial compartment is not well-developed as compared with the domestic horse. 相似文献
138.
N Sasaki S Hobo T Yoshihara 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(9):1059-1062
This study concerns the establishment of a simple testing method for breath concentration of hydrogen and methane in horses. Twenty-eight healthy thoroughbreds and 24 Arabians were used. Breath samples were collected using one-minute closed circulatory respiration through an aluminum bag filled with 10 liters of pure oxygen, which was mounted on the subjects by means of a face mask. Breath samples obtained, were analyzed by gas chromatography. A significant correlation in both hydrogen and methane levels was observed for samples collected at separate times. These findings confirmed the usefulness of our approach for testing breath concentrations of hydrogen and methane in horses. 相似文献
139.
We studied the effect of amylose content on the gelatinization, retrogradation, and pasting properties of starch using wheat starches differing in amylose content. Starches were isolated from waxy and nonwaxy wheat and reciprocal F1 seeds by crossing waxy and nonwaxy wheat. Mixing waxy and nonwaxy wheat starch produced a mixed starch with the same amylose content as F1 seeds for comparison. The amylose content of F1 seeds ranged between waxy and nonwaxy wheat. Nonwaxy‐waxy wheat had a higher amylose content than waxy‐nonwaxy wheat. Endothermic enthalpy and final gelatinization temperature measured by differential scanning calorimetry correlated negatively with amylose content. Gelatinization onset and peak temperature clearly differed between F1 and mixed starches with the same amylose content as F1 starches. Enthalpy for melting recrystallized starches correlated negatively with amylose content. Rapid Visco Analyser measurement showed that F1 starches had a higher peak viscosity than waxy and nonwaxy wheat starches. Mixed starches showed characteristic profiles with two low peaks. Setback and final viscosity correlated highly with amylose content. Some of gelatinization and pasting properties differed between F1 starches and mixed starches. 相似文献
140.
Tsutomu Ishimaru Hideyuki Hirabayashi Kazuhiro Sasaki Changrong Ye Asako Kobayashi 《Plant Production Science》2016,19(1):12-21
Global warming is predicted to aggravate the risk of unstable crop production. It is of great concern that damage to rice spikelet sterility and grain quality will increase, resulting in yield and economic losses. To secure the global food supply and farmers’ income, the development of rice cultivars with heat resilience is a pressing concern. Regarding spikelet sterility, rice cultivars with heat tolerance at different growth stages have been identified in recent years. The early-morning flowering (EMF) trait is effective in heat escape because it shifts the time of day of flowering to earlier in the morning when it is cooler. Although varietal differences are very small, there are some genetic resources for EMF in wild rice accessions. Regarding heat-induced grain chalkiness, heat-tolerant japonica cultivars for mitigating white-back type of chalky grains (WBCG) were found. Quantitative trait loci for heat tolerance at flowering, EMF, and for WBCG in grain quality have been mapped on the rice chromosomes. Further genetic efforts have been successfully connected to the development of near-isogenic lines for each trait with tagged molecular markers. These breeding materials are quite unique and useful in facilitating marker-assisted breeding toward the development of heat-resilient rice in terms of spikelet sterility and grain quality. 相似文献