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41.
Ten reared cows of a Japanese Black cattle herd in Kagoshima prefecture, Japan, exhibited extremely low blood urea nitrogen (BUN) concentration (2.6 ± 0.6 mg/dL). Examination of dietary feed nutrition and relevant pastureland soil content suggested a correlation with crude protein (CP) deficiency or unbalanced nutritional dietary feeds. Thirteen months after the introduction of a dietary remedial measure (bean cake supplementation), BUN, total cholesterol and albumin concentration from five of the original 10 cows increased significantly compared with their values of before the dietary remedy. The postpartum day open period was significantly lower after the dietary remedial measure than that before it. The abnormally low BUN levels of the cattle herd may be due to inadequate dietary nutritional content, primarily from the imbalance of total digestible nutrient and CP of the feed and far lower han average CP value. In conclusion, routine examination of serum biochemical parameters in Japanese Black breeding cattle may be a useful strategy for determining subclinical metabolic failure of cattle herds, and consequently, its effect on reproductive performance of the herd.  相似文献   
42.
Mesoscopic quantum phase coherence is important because it improves the prospects for handling quantum degrees of freedom in technology. Here we show that the development of such coherence can be monitored using magnetic neutron scattering from a one-dimensional spin chain of an oxide of nickel (Y2BaNiO5), a quantum spin fluid in which no classical static magnetic order is present. In the cleanest samples, the quantum coherence length is 20 nanometers, which is almost an order of magnitude larger than the classical antiferromagnetic correlation length of 3 nanometers. We also demonstrate that the coherence length can be modified by static and thermally activated defects in a quantitatively predictable manner.  相似文献   
43.
44.
ABSTRACT:   To elucidate the hemolytic suppression roles of taurine and the necessity of dietary taurine supplementation in yellowtail Seriola quinqueradiata fed a diet without fishmeal, juvenile fish with an initial body weight of 250 g were fed for 40 weeks in floating net cages on soybean protein diets supplemented with 0, 3.0, 4.5 and 6.0% taurine. Taurine concentration of the experimental diets were 0.03, 33.9, 52.8 and 71.6 mg/g, respectively. On the 21st week, fish fed the taurine unsupplemented diet had inferior growth and feed performances, higher death, and there were incidences of green liver and hemolytic anemia. In this group, hepatic and plasma taurine concentrations, serum osmolality and osmotic tolerance of erythrocytes (EC50 value) were significantly lower, and plasma hydroperoxide concentration was markedly higher than in the taurine supplemented groups. These conditions markedly improved corresponding with the increase of dietary taurine concentration. These results indicate that taurine plays a role in hemolytic suppression through osmoregulation and biomembrane stabilization in fish. In addition, it is suggested that yellowtail requires dietary taurine as an essential nutrition for maintaining physiological condition normally.  相似文献   
45.
A 6-month-old female Border Collie was examined because of a 1-month history of progressive curvature of the cervical portion of the vertebral column. Radiography revealed severe cervical and thoracic scoliosis. Cervical syringomyelia and hydrocephalus were observed by means of magnetic resonance imaging. Suboccipital craniotomy and laminectomy of the first cervical vertebra were performed, and substantial improvement in the scoliosis and syringomyelia was observed 3 months after surgery. No recurrences were seen during the first year after surgery.  相似文献   
46.
1. To clarify the difference in behavioural activities and catecholamine metabolism between layer and broiler-type chicks two experiments were conducted. 2. In experiment 1, 1-d-old male layer and broiler chicks were placed in an open-field area and their responses were investigated for 10 min. The responses of the two strains were remarkably different, with broilers being less active than layers. Vocalisations rapidly decreased in broilers whereas those of layers remained elevated during the 10 min. 3. In experiment 2, 1-d-old chicks of both strains were killed and brain catecholamine concentrations were determined in three parts of the brain: telencephalon, optic lobe and brain stem. 4. In the whole brain, dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) were significantly higher in broilers. However, the values for norepinephrine (NE), epinephrine (E) and 4-hydroxy-3-methoxyphenylacetic acid (HVA) were similar between strains. The ratios of metabolite/precursor were also calculated: HVA/DOPAC was higher in layers, while NE/DA, E/NE and DOPAC/DA were not significantly different between strains. 5. These results suggest that behavioural activities differ greatly, while there are some differences in catecholamine metabolism between the two strains.  相似文献   
47.
We measured the blood plasma testosterone (T) levels and superoxide dismutase (SOD) and catalase activities in the seminal plasma of the ejaculates of 5 normal (2-5 years old) and 5 asthenozoospermic (AZ-) (3-5 years old) Beagles. Sperm ejaculated by AZ-dogs was incubated for 3 hr in Eagle's MEM only (controls) or Eagle's MEM containing 100 units/ml of SOD or catalase. Sperm motility was examined during incubation. The mean (+/- SE) plasma T level of the AZ-dogs (1.2 +/- 0.2 ng/ml) was significantly lower than in the normal dogs (2.5 +/- 0.2 ng/ml) (P<0.005). The mean (+/- SE) seminal plasma SOD and catalase activities (18.8 +/- 1.9 and 0.5 +/- 0.1 unit/g protein, respectively) were significantly lower in the AZ-dogs than in the normal dog (43.3 +/- 2.5 and 2.2 +/- 0.4 unit/g protein, respectively) (P<0.001 and 0.01, respectively). The motility of sperm incubated in Eagle's MEM containing SOD or catalase was significantly higher than that of control sperm incubated in only Eagle's MEM after 2 or 3 hr of incubation (P<0.05). The results of this study indicate that poor T secretion by the testes and low antioxidant enzyme activities are related to AZ in the dog.  相似文献   
48.
Magnetic neutron scattering provides evidence for nucleation of antiferromagnetic droplets around impurities in a doped nickel oxide-based quantum magnet. The undoped parent compound contains a spin liquid with a cooperative singlet ground state and a gap in the magnetic excitation spectrum. Calcium doping creates excitations below the gap with an incommensurate structure factor. We show that weakly interacting antiferromagnetic droplets with a central phase shift of pi and a size controlled by the correlation length of the quantum liquid can account for the data. The experiment provides a quantitative impression of the magnetic polarization cloud associated with holes in a doped transition metal oxide.  相似文献   
49.
The cathelicidin family is one of the several families of antimicrobial peptides (AMPs). A bovine myeloid antimicrobial peptide (BMAP‐28) belongs to this family. Recently, the emergence of drug‐resistant bacteria such as methicillin‐resistant Staphylococcus aureus (MRSA) has become a big problem. AMPs are expected to be leading compounds of new antibiotics against drug‐resistant bacteria. In this study, we focused on the activity of BMAP‐28 against bacterial cell surfaces. First, we observed morphological change of MRSA caused by BMAP‐28 using a scanning probe microscope. We also studied activities of BMAP‐28 against adherence of S. aureus to fibronectin, collagen type I, collagen type IV. We confirmed whether BMAP‐28 can bind to lipoteichoic acid (LTA) of S. aureus. BMAP‐28 was indicated as damaging the cell surface of MRSA. In a particular range of concentrations, BMAP‐28 promoted adherence of S. aureus against fibronectin and collagens. It was revealed that BMAP‐28 and LTA of S. aureus bound with each other. Our study showed the potential of BMAP‐28 which can damage MRSA and interact with LTA of S. aureus but promote its adherence in some concentrations. This study provides new points of which to take notice when we use AMPs as medicines.  相似文献   
50.
Frozen feline semen was prepared using two types of extenders, egg yolk Tris-fructose citric acid (EYT-FC) and egg yolk sodium citrate solution (EYC), and the semen qualities after thawing and the conception rates obtained by unilateral intrauterine horn insemination (UIUI) were investigated. Cats used in the experiment were six males and 11 females aged 2-12 years (the number of experimental cases was 17). For preparation of frozen semen, semen collected by the artificial vagina method was adjusted to I x 10(8) sperm/m/ and 7% glycerol, put in 250 microl straws, and then frozen using a cell freezer. The mean sperm motility after thawing was 30.0+/-9.7 (SE) % in the semen prepared with EYT-FC and 30.0+/-3.3% in the semen prepared with EYC. Four of seven animals were fertilized by UIUI using two straws in both extenders, and the conception rate was 57.1%. The mean ratios of number of kits to the number of ovulations in the inseminated side were 61.1+/-24.5% and 30.5+/-3.4% for EYT-FC and EYC, respectively, showing that the ratio tended to be higher in the semen prepared with EYT-FC. The above findings, comparing the two extenders for preparation of frozen feline semen, showed that EYT-FC is slightly superior to EYC. To increase conception and fertility rates, it may be important to increase the sperm count for insemination and to inseminate both uterine horns.  相似文献   
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