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451.
The aim of the study was to determine parameters reflecting equine anxiety trait by comparing results obtained in a behavior test and an anxiety score assessed by familiar caretakers in response to a questionnaire. In the behavior test, horses were individually led into a novel room by their caretakers and loosely tethered to decrease excessive movement using the common cross-tying technique with two leads and breakable plastic cords. The horses initially remained with their caretaker for 2 min; the caretaker then left and the subject animal was left alone for 2 min. The latency to break the plastic cords, heart rate, the number of steps and pawings were recorded. When the horses were left alone, most parameters changed significantly and some showed sexual differences. A correlation analysis revealed that anxiety score assessed by caretakers showed a negative correlation with the latency to break the plastic cord and a positive correlation with heart rate only when horses were isolated. These two were suggested feasible parameters for assessing the anxiety trait of unfamiliar horses. Both the behavioral results and the anxiety scores also indicated that females were more anxious than males. Our results suggest that it would be a useful strategy for assessing other temperament traits as well to combine behavior tests with a questionnaire survey.  相似文献   
452.
Concentrations of metabolites and immunoreactive insulin (IRI) and activities of enzymes related to energy metabolism were measured in plasma of Korean and Japanese beef cattle, which were raised by the indoor feeding system programmed to feed larger amount of roughage in their growing periods and larger amount of concentrate diet in their finishing periods (Japanese feeding system), and grazing New Zealand beef cattle. By the Japanese beef grading system, Korean and Japanese beef cattle showed high beef quality score, average grade 3.3 and 3.6, respectively. The plasma free fatty acid and lactate concentrations and lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and aspartate aminotransferase (AST) activities in Korean beef cattle were significantly higher than those in Japanese beef cattle. The plasma lactate concentration in Korean beef cattle was 8.40 mmol/l, which was similar to the values observed in lactic acidosis. The higher activities of plasma LDH, MDH and AST may indicate slight liver damage by slightly acidotic conditions in Korean beef cattle. New Zealand beef cattle fed on pasture which they harvest by grazing showed significantly lower plasma glucose, cholesterol, lactate and IRI concentrations and enzyme activities than those in Korean and Japanese beef cattle fed on larger amount of concentrate diets. Plasma metabolite concentrations and energy metabolism-related enzyme activities may be good indicators for evaluating metabolic conditions of beef cattle raised by different feeding systems.  相似文献   
453.
We studied the effect of salinity on nail-hold-ing power in wood construction. In saline solution, the holding power of nails was less than in purified water. With the increase of salt concentration, t...  相似文献   
454.
The action of a novel protein-glutaminase from microorganisms on alpha-lactalbumin was investigated. When alpha-lactalbumin in the native state was incubated with protein-glutaminase, the deamidation proceeded gradually, i.e., the deamidation degree increased to 20% and 55% after 4 and 24 h, respectively. The transformation of alpha-lactalbumin from the native state to the molten globule state caused an increase in the rate of the enzyme-catalyzed deamidation, particularly in the early stage. The deamidation degree for the molten globule state reached 61% after 4 h, followed by a gradual increase to 66% after 24 h. CD spectral analyses of deamidated alpha-lactablumin revealed that the stability of the tertiary structure of alpha-lactablumin was closely related to the degree of deamidation, whereas the secondary structure was not affected by deamidation. Glutamine residues in alpha-lactalbumin to be modified by protein-glutaminase were identified as Gln[39], [43], [54], and [65]. Conformational characteristics of the amino acid sequence around these glutamine residues are discussed.  相似文献   
455.
Wang  Cong  Mori  Taiki  Mao  Qinggong  Zhou  Kaijun  Wang  Zhuohang  Zhang  Yongqun  Mo  Hui  Lu  Xiankai  Mo  Jiangming 《Journal of Soils and Sediments》2020,20(2):921-930
Journal of Soils and Sediments - Phosphorus (P) addition could largely alter soil microbial activity. However, effects of long-term P addition on soil extracellular enzyme activity are not well...  相似文献   
456.
An annual Echinochloa with plagiotropic tillers (semi‐erect type) was found on a paddy levee in Miyagi prefecture in Japan. This semi‐erect type had tetraploid chromosome numbers (2n = 36) and would be expected to be E. oryzicola. However, its appearance was distinct from that of E. oryzicola. To collect seed samples and clarify its distribution and habitat, exploration and collection surveys were carried out in the northern part of Honshu, the main island of Japan in 2014, 2017, and 2018. Thirty‐two populations that were assumed to be the semi‐erect type were found and their mature seeds were collected. Based on the results of chromosome counts and growth form analyses, all of them were confirmed to be the semi‐erect type. The 32 populations were distributed in the prefectures of Aomori, Iwate, Akita, Miyagi, Yamagata, Fukushima, and Niigata, and located in paddy fields, abandoned paddy fields, paddy levees, roadsides, vacant land, and scree slopes. Our surveys indicated that the semi‐erect type grew in wet and dry disturbed habitats at an early stage of secondary succession including paddy fields in the northern part of the main island of Japan.  相似文献   
457.
This study evaluated the control of streptococcosis outbreaks in Brazil, isolated from diseased sorubim and identified as Lactococcus garvieae by genetic sequencing. This report determined the potential for lactococcosis control in sorubim Pseudoplatystoma sp. with two vaccines: an aqueous‐based, whole‐cell inactivated vaccine (bacterin) and an oil‐adjuvanted bacterin. Their efficacy was evaluated at 30 days post‐vaccination (d.p.v.) by challenge with L. garvieae, and the antibody production response at 15, 30 and 60 d.p.v. and the non‐specific immune response were compared amongst treatments. High protection levels (P < 0.05) were achieved with the oil‐adjuvanted vaccine with a relative percentage survival value of 81.7% at 30 d.p.v. Additionally, the oil‐adjuvanted vaccine increased the immunogenicity of the bacterin as indicated by greater agglutination antibody titres from 15 until 60 d.p.v. This is the first report of a positive effect of vaccine administration on the specific immunity of sorubim, and the study showed that a specific antibody plays an important role in sorubim defence against lactococcosis because the innate immune responses were similar in all of the studied animals. These results demonstrated that oil‐adjuvanted vaccine can be an effective alternative for the protection of sorubim from L. garvieae disease.  相似文献   
458.
The stimulatory effect of the red microalga Porphyridium cruentum on respiratory burst activity of sole phagocytes was evaluated in vivo . Oral administration of a diet supplemented with lyophilized P. cruentum cells (10 g kg−1) stimulated respiratory burst activity after 4 weeks feeding in sole vaccinated with Photobacterium damselae subsp. piscicida bacterin.  相似文献   
459.
We examined the two acute phase proteins, alpha (alpha)-1 acid glycoprotein (AGP) and haptoglobin (HP), in serum of pigs following experimental porcine reproductive and respiratory syndrome (PRRS) virus infection. Increased levels of serum HP, but not AGP, were observed from 7 to 21 days post-inoculation in the infected pigs. Furthermore, serum IL-6 increased in the infected pigs, but TNF-alpha did not. The increase of serum IL-6 in pigs following PRRS virus infection may induce production of HP. Also, in the field investigation, serum HP in pigs was dramatically increased after exposure to the PRRS virus.  相似文献   
460.
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