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31.
Contagious yawning is triggered by others yawning, and it has previously been reported in humans, primates and several experimental and companion mammals. Whereas it might be a response to an innate releasing mechanism, contagious yawning is also considered to involve emotional contagion. Here, we demonstrate that sheep, the animal model of livestock animals, also experience contagious yawning. Twelve adult castrated Corriedale sheep were used in this study. Pairs of sheep were adjacently restrained with or without a wooden divider panel to shield them from viewing the other. Their behaviors were video‐recorded for 3 days in each condition. Sheep yawned 2.0 ± 1.1 and 1.2 ± 1.1 times/day/head in the unshielded and shielded conditions, respectively. Unshielded restrained sheep yawned within 1 min after the other one 11.1% of the time, while shielded pairs did not exhibit contagious yawning. Rumination was also highly synchronized under the unshielded condition. These data reveal that contagious yawning and behavioral synchronicity occur in ruminants like sheep, making them a suitable animal model to investigate contagious yawning and the underlying mechanism.  相似文献   
32.
Carrot (Daucus carota) somatic embryogenesis has been extensively used as an experimental system for studying embryogenesis. In several plant species, late embryogenesis abundant (LEA) genes are reported as the embryogenesis-related genes that are specifically expressed in embryonic tissues. Several LEA genes have been isolated for carrot somatic embryogenesis. The carrot LEA genes DC8 and ECP63 have very similar nucleotide sequences, and the gene pair is likely to be a nucleotide polymorphism. In several carrot cultivars, plants in which only DC8 was detected (DD genotype), only ECP63 was detected (EE genotype), and both DC8 and ECP63 were detected (DE genotype) have been observed via genomic PCR. Furthermore, distinct frequencies of the genotypes were observed in some carrot cultivars. These results suggested that detection of the nucleotide polymorphism might be useful in defining carrot cultivars. In addition, DC8 and ECP63, which include 14 amino acid insertions/deletions and 21 amino acid substitutions, may have similar effects on somatic embryogenesis, as all genotypes (DD, DE, and EE) were detected in some embryogenic cell lines. Therefore, the nucleotide polymorphism may be a useful candidate polymorphic marker that is easily detectable by PCR.  相似文献   
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34.
Computer-assisted physics can be considered the third approach besides experimental and theoretical physics. Numerical simulations are especially useful in the study of non-crystalline materials such as liquids, glasses, amorphous solids, and liquid crystals. Some applications of computer simulations to these materials are discussed.  相似文献   
35.
Methoxychlor (MXC) is a non-steroidal pesticide that is known to possess estrogenic activity, and therefore may be potentially hazardous to the development and/or reproduction. The present study assessed the effects of perinatal exposure to MXC on reproductive function after maturation in both male and female rats. Pregnant rats were fed a phytoestrogen-free diet containing different doses of MXC (24, 240, and 1200 ppm) from day 15 of gestation to day 10 after parturition, and reproductive functions of offspring were examined after maturation. In males, MXC exposure during the perinatal period decreased serum LH and FSH, but not testosterone levels, but it did not affect copulatory behavior. In females, MXC exposure prolonged the days exhibiting cornified vaginal smears during the estrous cycle. In addition, both the lordosis reflex and preovulatory LH surge on the presumptive proestrous evening were suppressed in MXC-exposed females. These results suggest that perinatal exposure to MXC exerts permanent effects on several aspects of the reproductive function in both male and female rats.  相似文献   
36.
Fifteen yearling steers were used to study the preventive effect of vitamin E on the protection against free radicals produced by carbon tetrachloride (CCl4). The animals were randomly divided in three equal groups and treated as follows: group A--previously injected (i.m.) with 15 IU/kg BW on the 15th and second day before the trial and drenched with 0.05 ml/kg BW CCl4; group B--only drenched with the same dose of CCl4; group C--drenched with a placebo. Food intake was recorded and blood samples collected daily for 8 days after the CCl4 drenching to compare the activity of aspartate aminotransferase (AST), gamma-glutamyltransferase (gamma-GT) and the levels of erythrocyte reduced glutathione (GSH) and serum malonyldialdehyde (MDA). Food intake was reduced in group B for the first 3 days (P < 0.05); higher activities of AST and gamma-GT were observed in the poisoned groups, nevertheless the overall values were lower in the group A than B (P < 0.02); only the group A reached the basal values of AST at the seventh day; higher levels of GSH and MDA were recorded in the poisoned cattle indicating the generation of free radicals. It was concluded that the preventive use of Vitamin E lessened the damage in hepatic tissue caused by the free radicals and prevented the anorexia caused by CCl4.  相似文献   
37.
OBJECTIVE: To compare a sensor-based accelerometer-gyroscopic (A-G) system with a video-based motion analysis system (VMAS) technique for detection and quantification of lameness in horses. ANIMALS: 8 adult horses. PROCEDURE: 2 horses were evaluated once, 2 had navicular disease and were evaluated before and after nerve blocks, and 4 had 2 levels of shoe-induced lameness, alternatively, in each of 4 limbs. Horses were instrumented with an accelerometer transducer on the head and pelvis, a gyroscopic transducer on the right forelimb and hind feet, and a receiver-transmitter. Signals from the A-G system were collected simultaneously with those from the VMAS for collection of head, pelvis, and right feet positions with horses trotting on a treadmill. Lameness was detected with an algorithm that quantified lameness as asymmetry of head and pelvic movements. Comparisons between the A-G and VMAS systems were made by use of correlation and agreement (kappa value) analyses. RESULTS: Correlation between the A-G and VMAS systems for quantification of lameness was linear and high (r2 = 0.9544 and 0.8235 for forelimb and hind limb, respectively). Quantification of hind limb lameness with the A-G system was higher than measured via VMAS. Agreement between the 2 methods for detection of lameness was excellent (kappa = 0.76) for the forelimb and good (kappa = 0.56) for the hind limb. CONCLUSIONS AND CLINICAL RELEVANCE: The A-G system detected and quantified forelimb and hind limb lameness in horses trotting on the treadmill. Because the data are collected wirelessly, this system might be used to objectively evaluate lameness in the field.  相似文献   
38.
Background: The basic and clinical implications of evaluating plasma atrial natriuretic peptide (ANP) concentration in calves are unknown.
Objective: To investigate the relationship between the plasma ANP concentration and left ventricular end-diastolic pressure (LVEDP) in healthy calves subjected to volume overload (Study 1), and to compare the plasma ANP concentration in calves with or without heart disease (Study 2).
Animals: Six healthy calves were used in Study 1; disease calves and sick calves with (n = 9) and without congenital heart disease (CHD) (n = 9) were used in Study 2.
Methods: In Study 1, LVEDP in anesthetized calves was manipulated by IV administration of acetated Ringer's solution (rate of 100 mL/kg/h for 20 minutes) and furosemide. In Study 2, disease calves were identified by blood examination and echocardiography or pathological examination. The plasma ANP concentration was determined by a chemiluminescence enzyme immunoassay for human α-ANP.
Results: In Study 1, preloading significantly increased the plasma ANP concentration (36 ± 20–185 ± 156, P < .01) and LVEDP (−11 ± 7–2 ± 12, P < .01) from the baseline. Furthermore, plasma ANP concentrations were strongly correlated with LVEDP ( r = 0.61). In Study 2, the plasma ANP concentration was significantly higher in the calves with CHD than in the calves without heart disease (220 [67–970] versus 31 [10–86]; mean [range], P < .001).
Conclusions and Clinical Importance: Measurement of plasma ANP concentrations in calves can provide additional information useful for predicting hemodynamic abnormalities.  相似文献   
39.
To investigate whether supplementation with iodine-reduced kelp (Laminaria japonica) powder decreases body fat composition in overweight Japanese subjects, a randomized, double-blind, placebo-controlled intervention study was conducted in 50 Japanese subjects with body mass index (BMI) ≥25 and <30 kg/m2. Subjects were randomly assigned to consume thirty tablets/d (10 tablets orally, 3 times/d) containing either iodine-reduced kelp powder (test, 6 g kelp powder corresponding to 3 g alginate/d) or kelp-free powder (placebo) for 8 weeks. Anthropometric measurements, blood lipids, and serum thyroid hormone levels were obtained before and after the trial. Body fat percentage was significantly decreased in male subjects from the test group compared with the placebo group. The same tendency was observed for body weight (p = 0.065) and BMI (p = 0.072) in male subjects. No significant changes in anthropometric measurements or visceral fat area were observed in female subjects. Serum thyroid hormone concentrations did not increase after 1.03 mg/d of iodine supplementation through kelp intake. The intake of iodine-reduced kelp powder led to significant and safe reductions in body fat percentage in overweight male subjects. The consumption of kelp high in alginate may contribute to preventing obesity without influencing thyroid function in Japanese subjects with a relatively high intake of iodine from seaweed.  相似文献   
40.
We previously reported that growth hormone (GH) pulses were negatively associated with neuropeptide Y (NPY) profiles in cerebrospinal fluid (CSF) of the third ventricle of Shiba goats. In addition, while most GH pulses were coincident with GH-releasing hormone (GHRH) pulses, there was no correlation between GH and somatostatin (SRIF) levels. The present study was performed to elucidate the relationship between GH pulses and these neuropeptide levels in CSF when estradiol (1.0 mg/head) was subcutaneously administered to ovariectomized goats. CSF and plasma samples were collected every 15 min for 18 h (from 6 h before to 12 h after injection). GH levels in peripheral blood and GHRH, SRIF and NPY levels in CSF were measured by radioimmunoassay. Pulse/trough characteristics and correlations were assessed by the ULTRA algorithm and cross-correlation analysis. Before estradiol was injected, significant coincidence was found between GHRH pulses and GH pulses, and negative coincidence was found between NPY troughs and GH pulses. Six to 12 h after estradiol injection, the amplitude and area under the curve (AUC) of the GH pulses were markedly increased. The duration and AUC of the GHRH pulses in the CSF were also increased, and stronger synchrony of GHRH with GH was observed. In contrast, the baseline of NPY was significantly decreased, and the negative correlation between the GH pulses and NPY troughs disappeared. The parameters of SRIF troughs were not clearly changed. These observations suggest that estrogen enhances the pattern of secretion of GH in the goat via enhancement of GHRH pulses and decrease of NPY levels.  相似文献   
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