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31.
This study examined the production and welfare effects of including a large self‐feeder competent rainbow trout, Oncorhynchus mykiss (Walbaum) (~665 g) in groups of smaller self‐feeder competent conspecifics (~234 g). Costs and benefits were examined for both welfare (aggression, fin damage, condition and mortality) and production (self‐feeder utilization and growth). The 8‐week experiment used six groups of small trout; three treatment groups containing a large trout and three control groups. After 4 weeks the large fish were removed from treatment groups and added to control groups, thus reversing the treatments. Whilst it was thought that the presence of a larger fish would suppress aggression in smaller conspecifics this did not occur. In fact aggression was significantly (= 0.036) higher when large trout were present during the first 4 weeks. No significant differences were found between other welfare indicators, self‐feeder utilization or production parameters. From a production and welfare perspective these results suggest that with the exception of initially increasing aggression larger fish do not represent a significant benefit or risk to smaller conspecifics being cultured in self‐feeder equipped tanks, when all fish are self‐feeder competent.  相似文献   
32.
A 42-day-old heavy draft horse fell into sudden astasia. Significant swelling and heat sensation of the left femoral region were observed. Because of a friction sound in the left hip, we supposed that the hip joint was dislocated or the hip bone was fractured. Computed Tomography (CT) examination showed that the left hip joint was dislocated and the left femoral head was disjunct. We carried out a pathological autopsy, and made a diagnosis of the foal as fracture of the hip bone and femoral head with suppurative umbilical arteritis. Pathologic changes in the umbilical artery and hind leg were completely unilateral, suggesting that left umbilical arteritis spread to the blood circulation, causing arthritis and dislocation of the hip bone.  相似文献   
33.
Pathogenic characters of Japanese potato strains of Ralstonia solanacearum   总被引:1,自引:0,他引:1  
Ralstonia solanacearum (Rs) strains in phylotypes I and IV isolated from potato in Japan were investigated for pathogenicity on potato, tomato, eggplant, Solanum integrifolium, tobacco, groundnut, and pumpkin. The strains were divided into 17 types based on differences in their pathogenicity on the tested plants. Particularly, the pathogenicity of most phylotype I strains on eggplant was distinctly different from that of the phylotype IV strains. When nine potato varieties (included two breeding lines) were inoculated with several Rs strains, phylotype IV strains were highly virulent on the breeding lines that are regarded as resistant to phylotype I strains.  相似文献   
34.
Analysis of the effect of slow-releasing N fertilizers on microbial parameters of the rhizosphere soil is essential for their effective use. This investigation revealed the comparative effects of oxamide and ammonium sulfate as different N sources on some selected microbial parameters as well as the pH in the rhizosphere of wheat (Triticum aestivum cv. Nourin No. 61). The study was conducted on a Japanese upland alluvial soil using a rhizobox system. In the central compartment (CC) of the rhizoboxes treated with oxamide and ammonium sulfate, four wheat seedlings were grown for 53 d. In either of the treatments, the pH of the rhizosphere soil increased with the increase in the distance from the CC. In contrast, nitrate production, bacterial and fungal numbers, microbial biomass nitrogen, and β-acetylglucosaminidase activity decreased with the increase in the distance, with the highest values of the respective parameters being recorded in the CC. However, remarkable changes of these microbial parameters were found within a distance of 1–2 mm from the CC to the distant compartments. Thus the results indicated that pH, bacterial number, and nitrate production were high in the oxamide treatment. In contrast, higher fungal number, microbial biomass N, and .B-acetylglucosaminidase activity were associated with the ammonium sulfate treatment. It was assumed that the significant (p<O.05) effect of the rhizosphere on microbial activities varied with the treatments.  相似文献   
35.

Background  

Students suffering from psychosomatic symptoms, including drowsiness and feelings of melancholy, often have basic lifestyle problems. The aim of this study was to investigate whether psychosomatic complaints may be related to circadian dysfunction.  相似文献   
36.
The objective of this study was to confirm the stability of the genetic estimation of longevity of the Holstein population in Japan. Data on the first 10 lactation periods were obtained from the Livestock Improvement Association of Japan. Longevity was defined as the number of days from first calving until culling or censoring. DATA1 and DATA2 included the survival records for the periods 1991–2003 and 1991–2005, respectively. The proportional hazard model included the effects of the region-parity-lactation stage-milk yield class, age at first calving, the herd–year–season, and sire. The heritabilities on an original scale of DATA1 and DATA2 were 0.119 and 0.123, respectively. The estimated transmitting abilities (ETAs) of young sires in DATA1 may have been underestimated, but coefficient δ, which indicated the bias of genetic trend between DATA1 and DATA2, was not significant. The regression coefficient of ETAs between DATA1 and DATA2 was very close to 1. The proportional hazard model could steadily estimate the ETA for longevity of the sires in Japan.  相似文献   
37.
This article describes the catalytic effect of NaHCO3 on condensation reactions of monomeric hydroxymethylphenols (HMPs) to elucidate the cure-acceleration mechanism. By comparison of the kinetics of self-condensations of HMPs, NaHCO3 was proved to increase the reactivity of para-hydroxymethyl groups. The changes of 13C nuclear magnetic resonance (NMR) chemical shifts on each HMP system with the additive indicated that the addition of NaHCO3 enhanced some molecular interactions between HMPs and NaHCO3, facilitating a resonance effect that might play a similar role in dissociation of the phenolic hydroxyl groups of HMPs. In addition, computational modeling by molecular orbital calculations elucidated that hydrogen carbonate anion (HCO 3 ) forms an interaction between either the para-hydroxymethyl group and the phenolic hydroxyl group or between the two para-hydroxymethyl groups of HMPs by hydrogen bonds. From the experimental results, the authors proposed the mechanism of the catalytic action of NaHCO3: it appears to be due to the delocalization of an electron initiated by the interaction of the para-hydroxymethyl groups and the phenolic hydroxyl of HMPs with HCO 3 through hydrogen bonds, which results in facilitating the formation of active species.  相似文献   
38.
Prevalence of equine gastric ulcer syndrome in 85 young Thoroughbreds was investigated. The presence of gastric ulcers was confirmed in 27.1% (23/85) of the horses by endoscopic examination. Sixty-two horses without gastric ulcers were allocated randomly to either the treated group (31 horses) or sham-dosed control group (31 horses) in order to investigate the efficacy of omeprazole oral paste in the prevention of gastric ulcers. At the second endoscopic examination conducted after 28 days of administration, only 1 horse in the treated group developed gastric ulcers, while 12 horses developed gastric ulcers in the control group. Based on these data, the efficacy of omeprazole in prevention of equine gastric ulcers in young Thoroughbreds during the training period was confirmed.  相似文献   
39.
A female stillborn Holstein calf with shortened cervical and thoracic regions, protrusion of the tongue, and bilateral symmetric flexural contraction of the anterior limbs was delivered on gestation day 281. Multiple hemivertebrae, fused and misshaped vertebrae, synostosis and scoliosis of cervical, thoracic and lumbar vertebral column were found in the affected calf by radiographic and computed tomographic (CT) analysis. Ten pairs of ribs were present and the sternum consisted of 9 sternebrae. Multiple morphologic abnormalities including fusion, malformation, and displacement, were found in the ribs and sternum. Cardiac anomalies, including atrial septal defect and hypertrophy of right ventricle, were observed. DNA-polymerase chain reaction (PCR) analysis demonstrated that amplified product from the liver DNA of the affected calf had identical pattern to that associated with complex vertebral malformation (CVM) of Holstein calves and that her dam was a heterozygous carrier of CVM. The affected calf was diagnosed as having CVM based on the DNA-PCR results and the characteristic findings, and was recorded as a first documentation of CVM confirmed in a Holstein calf in Japan.  相似文献   
40.
About 140,000 years ago, the breakup of large continental ice sheets initiated the Last Interglacial period. Sea level rose and peaked around 135,000 years ago about 14 meters below present levels. A record of Last Interglacial sea levels between 116,000 years to 136, 000 years ago is preserved at reef VII of the uplifted coral terraces of Huon Peninsula in Papua New Guinea. However, corals from a cave situated about 90 meters below the crest of reef VII are 130, 000 +/- 2000 years old and appear to have grown in conditions that were 6 degreesC cooler than those at present. These observations imply a drop in sea level of 60 to 80 meters. After 130,000 years, sea level began rising again in response to the major insolation maximum at 126,000 to 128,000 years ago. The early (about 140,000 years ago) start of the penultimate deglaciation, well before the peak in insolation, is consistent with the Devils Hole chronology.  相似文献   
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