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21.
Various studies have shown the associations between differences in human behavioral traits and genetic polymorphism of neurotransmitter-related proteins such as receptors, transporters and monoamine oxidase. To clarify the genetic background of animal behavior, corresponding regions in animals have been analyzed. The study has been especially focused on primates, as the evolutionally closest animal to humans, and on dogs, as the socially closest animal to humans. In primates, polymorphisms were discovered between or within species, and the functional effects on neural transmission were found to be different by alleles. Even in apes, the closest species to humans, function was different from that in humans. In dogs, allele distributions of several genes were different among breeds showing different behavioral traits, and genes associated with individual differences in aggressiveness and aptitude of working dogs were surveyed. The survey of behavior-related genes has also been carried out in other mammals such as horses and cetaceans. Genes controlling various behaviors in birds have also been reported. The marker genes for behavior will provide useful information for human evolution, welfare of zoo animals and effective selection of working dogs and industry animals.  相似文献   
22.
Artificial insemination with frozen cauda epididymal sperm was performed in cats. Sperm were transmigrated from the epididymides in 10 male cats. The mean sperm motility and viability were 67% and 82.5%, respectively, and 11.6 x 10(7) sperm were recovered. The mean sperm motility after thawing was 24.0%. Eleven female cats received unilateral intrauterine insemination of 5 x 10(7) sperm, and the conception rate was 27.3% (3/11). This was the first case of conception obtained with frozen epididymal sperm in cats.  相似文献   
23.
In the plant cell wall of Pisum sativum seedlings, we found an NTPase (E.C. 3.6.1.5.) with ATP-hydrolyzing activity that was regulated by an elicitor and suppressors of defense from pea pathogen Mycosphaerella pinodes. The ATPase-rich fraction was purified from pea cell walls by NaCl solubilization, ammonium sulfate precipitation, and chromatography with an ATP-conjugated agarose column and an anion-exchange column. The specific activity of the final ATPase-rich fraction increased 600-fold over that of the initial NaCl-solubilized fraction. The purified ATPase-rich fraction also had peroxidase activity and generated superoxide, both of which were regulated by the M. pinodes elicitor and suppressor (supprescins). Active staining and Western blot analysis also showed that the ATPase was copurified along with peroxidases. In this fraction, a biotinylated elicitor and the supprescins were bound primarily and specifically to ca. 55-kDa protein (CWP-55) with an N-terminal amino acid sequence of QEEISSYAVVFDA. The cDNA clone of CWP-55 contained five ACR domains, which are conserved in the apyrases (NTPases), and the protein is identical to a pea NTPase cDNA (GenBank accession AB071369). Based on these results, we discuss a role for the plant cell wall in recognizing exogenous signal molecules.  相似文献   
24.
To develop an efficient method to inoculate Chinese cabbage seedlings with the root endophytic fungus Heteroconium chaetospira, an appropriate nursery soil and glucose concentration for the nutrient medium for fungal colonization were determined. A grid-sheet method was established for estimating the degree of colonization of entire roots by the fungus. The fungus colonized at high frequencies when peat moss was used as the rooting medium. Colonization was highest (75%) when peat moss was amended with 0.1% glucose. Under these conditions, fungal hyphae developed intracellularly in root cortical cells. In contrast, under high glucose conditions, fungal colonization was restricted mostly to intercellular regions of epidermal or cortical root tissues. Here, hyphae formed inter- or intracellular microsclerotia. Received 19 August 2002/ Accepted in revised form 5 December 2002  相似文献   
25.
ABSTRACT:   For bioremediation of organically enriched sediment deposited below fish farms, the extremely high potential for population growth of a deposit-feeding polychaete, Capitella sp. I, in the organically enriched sediment, and the effect on decomposition of organic matter in the sediment, were examined. A mass-culturing technique was conducted for this species. Bioremediation experiments were conducted on the organically enriched sediment in a fish farm in Kusuura Bay, Japan in 2003–2006. Approximately 1.7 million individuals of the worms were placed on the sediment below one net pen in December 2003, 9.3 million individuals in November 2004, and 2.2 million individuals in November 2005. After the worms were spread on the sediment, they rapidly increased in number and reached the highest densities of approximately 134 000 inds/m2 in February 2004, 527 000 inds/m2 in March 2005 and 103 000 inds/m2 in January 2006. In the process of rapid population growth, the decomposition of the organic matter of the sediment was enhanced markedly. Our results demonstrate that the promotion of population growth by spreading cultured colonies of Capitella can enhance the decomposition rate of organic matter markedly in organically enriched sediment below fish farms. This method is promising for minimization of the negative effects of fish farms.  相似文献   
26.
27.
ABSTRACT:   A microscopic bubble generating system (MBGS) has been developed to control dissolved oxygen (DO) levels suitable for fish farming. The MBGS has been tested to confirm its capability in net pens. Water conditions in a fish farm were monitored every two hours from June to October 2004 by setting an online vertical profiling system (OVPS) close to the net pen. DO in the net pen water decreased to physiologically stressful levels for the fish during the night (4.84–5.51 mg/L), while the DO was kept in saturated conditions during the day, due to oxygen supply from phytoplankton. The MBGS was operated from the evening to the morning of the next day for 16 h, to successfully create DO-saturated conditions in the net pen water at night. By using microscopic bubbles during the warm seasons, DO levels in the net pen water could be improved to a level suitable for fish farming. However, the low DO levels (<5.0 mg/L) of the bottom water occasionally extended to the net pen layers, despite the supply of microscopic bubbles to the water. To maintain the DO of the net pen water at levels suitable for fish farming, DO supply to the net pen water and the bottom water needs to be increased, and the organically enriched sediment just below the net pens needs to be treated.  相似文献   
28.
We investigated the feasibility of using several fast-growing tropical or subtropical hardwood species for timber production by measuring key wood qualities in relationship to the high rates of lateral growth. The trees tested were sampled from even-aged plantations of Acacia mangium, A. auriculiformis, hybrid Acacia (A. mangium × A. auriculiformis), Eucalyptus grandis, E. globulus, and Paraserianthes falcataria (Solomon and Java origin) that had already reached commercial harvesting age. The released strain of the surface growth stress (RS), xylem density (XD), microfibril angle (MFA), and fiber length (FL) were measured at the outermost part of the xylem at breast height in each tree. Results were then compared to the lateral growth rate (radius/age) at breast height, which provides a relative indicator of the amount of tree growth per year. Our findings indicated that RS was constant, regardless of lateral growth rate in each species. Similar results were observed for XD, MFA, and FL, with a few exceptions, suggesting that high growth rates do not intrinsically affect the wood properties of fast-growing tropical or subtropical species that have reached harvesting age. However, special attention must be paid to patterns of xylem maturation when developing plantations of such species.  相似文献   
29.
Climate change resulting from increased atmospheric carbon dioxide (CO2) and shortages of fossil fuels such as petroleum are major problems worldwide. Under these conditions, demand for woody biomass resources is increasing. We investigated the feasibility of using fast-growing Eucalyptus grandis for material production. Samples of E. grandis were collected from four plantations in different latitude divisions, including tropical and subtropical Brazil and subtropical Argentina. Various xylem qualities were measured and related to the lateral growth rate. Lateral growth rate did not significantly affect the longitudinal released strain of the surface growth stresses or the xylem density at any of the sampling sites. Higher lateral growth rate, higher values of xylem density, and lower absolute values of the released strain were observed in plantations closer to the equator. Higher growth rates in tropical climate promote longer fiber length. In subtropical plantations, smaller diameter trees will produce tension wood with smaller microfibril angles. Planting E. grandis closer to the equator thus produces higher quality wood than in plantations at lower latitudes.  相似文献   
30.
This study describes the successful use of modified dorsolumbar epidural anesthesia with a fixed volume of anesthetic in a bovine referral center. Among the 130 Holstein cattle scheduled for flank surgery, 90 cattle received a mixed anesthetic consisting of 1 ml of xylazine hydrochloride and 3 ml of lidocaine hydrochloride by modified dorsolumbar epidural anesthesia. Eighteen cattle with dehydration and/or lameness received a mixed anesthetic containing 0.5 ml of xylazine and 3 ml of lidocaine. Infiltration anesthesia was performed in 22 cattle whose epidural space could not be reached in order to perform the flank surgery. The surgeries began about 12 min after the administration of the anesthetic and lasted for about 36 min. The modified method using a fixed volume of anesthetic was successfully introduced and effectively used in a bovine referral center. This modified method will allow veterinarians to save time and effort, thus lowering the cost of each surgery.  相似文献   
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