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11.
Pavarot Noranarttragoon Yuji Ueda Tsutomu Hattori Takashi Matsuishi 《Fisheries Science》2011,77(4):497-502
The yield-per-recruit (YPR) analysis has been used to assess growth overfishing of exploited fish stocks. Since the ex-vessel
price per weight widely depends on the size of the fish, the result of the YPR does not imply the revenue. The value-per-recruit
(VPR) analysis, which is an economic expansion of the YPR analysis, was conducted for bighand thornyhead Sebastolobus macrochir caught off the Pacific coast of northern Honshu, Japan. The results showed that, for the current age at first capture (t
c = 3), the current fishing mortality (F = 0.12) was close to the optimum level. However, for the current F, optimum t
c in the VPR model was 8 years and would lead to a 47% increase compared to the current revenue. The maximum YPR was obtained
at t
c = 6 years, but the revenue at t
c = 6 only gave a 20% increase in the maximum revenue. The difference was caused by the size dependency of the ex-vessel price
per weight. The VPR model would generate fisheries management plans with both economical and biological consideration and
would help in making general consensus of fisheries management strategies. 相似文献
12.
Hypocretin/orexin is produced exclusively in the dorsal and lateral hypothalamus but its projection is widespread within the brain and plays important roles. In this paper, we review the independent discoveries of the hypocretin/orexin peptides, the neuroanatomy of this system, and the link to the sleep disorder narcolepsy that has led to the idea that this system plays a crucial role in the regulation of sleep and wakefulness. 相似文献
13.
14.
Kobayashi A Katagiri S Kimura T Ochiai K Umemura T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(9):773-777
The direct effects of three steroid hormones (progesterone, estradiol-17beta and corticosterone) on the growth of Neospora caninum (N. caninum) tachyzoite were examined in Vero cells. Subsequently, ovariectomized BALB/c mice infected with N. caninum were treated with physiological concentrations of the steroid hormones for 1 or 2 weeks. These hormones had no direct effect on the parasite growth in vitro. In the infected mice, there was no significant difference in the parasite distribution and histopathological changes between the hormone-injected and control groups. No mice showed parasitemia at the time of autopsy. These results suggest that physiological levels of steroid hormones (progesterone, estradiol-17beta and corticosterone) do not reactivate N. caninum in mice. 相似文献
15.
Hirabayashi M Hirao M Takahashi R Kimura K Hirasawa K Ueda M Hochi S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(10):1047-1052
Superovulation of female rabbits was induced by subcutaneous injection(s) of porcine FSH. Zygotes were recovered 17 to 19 hr after hCG injection and were classified into two categories under a microscope equipped with Nomarski interference-contrast optics at x 200 magnification: (A) zygotes with clearly visible pronuclei, or (B) zygotes with visualized pronuclei after 10 min centrifugation at 12,000 x g. No significant difference between strains was found in the proportion of category-A zygotes (JW 72.6% vs NZW 79.3%). Pronuclei of category-A zygotes were located in the center of the cytoplasm, and the pronuclei of category-B zygotes were slightly moved by centrifugation toward the mass of cytoplasmic lipid droplets. Exogenous DNA solution (5 microg/ml of fusion gene composed of bovine alphaS1-casein promoter and human growth hormone structural gene) was microinjected into the pronucleus of the JW zygotes. The pronucleus of category-A zygotes with a mean volume of 7.4 pl swelled up to 16.6 pl (132% increase), while that of category-B zygotes with a mean volume of 6.1 pl swelled up to 15.9 pl (148% increase). Nevertheless, similar proportions of category-A and category-B zygotes developed into offspring after transfer to recipient females (11.1 and 11.2%, respectively). The efficiency to produce hGH-carrying transgenic rabbits was 0.9% (2/235) from category-A zygotes and 0.5% (1/215) from category-B zygotes (P>0.05). To date, transgenic rabbits have been produced without centrifugation of pronuclear zygotes. However approximately 25% of fertilized rabbit zygotes can be used for DNA microinjection after they have been centrifuged to visualize their pronuclei. 相似文献
16.
Silvia Pietschmann Katrin Hoffmann Michael Voget Ulrich Pison 《Veterinary research communications》2009,33(6):489-505
The therapeutic value of antibiotics depends on the susceptibility of the infecting microorganism and the pharmacological
profile of the drugs. To assess the value of an antibiotic combination of polymyxin B and miconazole this study examined the
in vitro synergistic potential of the two drugs on Gram-negative and Gram-positive bacteria and yeast. Antifungal and antibacterial
activity was tested by minimum inhibitory concentration (MIC) of broth macrodilution and urea broth microdilution, by fluorescence
microscopy and flow cytometry. Synergism was calculated using the fractional inhibitory concentration index (FICi). With Staphylococcus intermedius as target we found up to an eightfold reduction of the individual MICs when both drugs were combined. However, the FICi was
0.63 suggesting no real interaction between the two drugs. With Escherichia coli, Pseudomonas aeruginosa, and Malassezia pachydermatis as targets the antimicrobial drug combination reduced the MICs of polymyxin B and miconazole from fourfold to hundredfold
resulting in FICi between 0.06 and 0.5 which defines a synergistic action. Thus, if polymyxin B and miconazole are combined
their effect is greater than the sum of the effects observed with polymyxin B and miconazole independently, revealing bactericidal
and fungicidal synergism. Our results indicate a strong therapeutic value for the combination of these antimicrobial agents
against Gram-negative bacteria and yeast and a weaker value against Gram positive bacteria for clinical situations where these
pathogens are involved. 相似文献
17.
Awareness of animal influenza and its prevention and control is important for ensuring livestock health, production and welfare. In China, a country stereotyped as a major source of emerging zoonotic infectious diseases, research on the public understanding of animal influenza is limited to the Han, the main ethnic group. The present qualitative study in Southwest China investigated awareness of animal influenza among the Dai, an ethnic minority. The participants (15 men and 10 women, ages 18–83) were smallholder farmers of pigs and poultry in rural areas of Jinghong, Xishuangbanna, Yunnan Province. A mixture of interviews and group discussions took place in homes and villages. The participants were asked about their knowledge of avian influenza (H7N9), swine influenza (H1N1), precautions taken to protect against influenza, procedures when animals were sick and perceived risk of animal influenza. The data were analysed following coding and thematic analysis. The findings demonstrated a limited understanding of animal health and welfare among participants. Specifically, they were largely unaware of animal influenza (H7N9, H1N1) including its causes, symptoms, prevention and treatment. The farmers were also uninformed of the risks they faced and unknowingly engaged in behaviours which increased direct or indirect exposure to infected animals, a risk factor for human infection. They also reported poor usage of veterinary services. In order to guarantee the health, welfare and production of their livestock, immediate action is needed to enable Dai smallholder farmers to prevent and respond to animal influenza effectively and timely. 相似文献
18.
Ezenduka EV Oboegbulem SI Nwanta JA Onunkwo JI 《Tropical animal health and production》2011,43(3):557-559
The use of antimicrobial agents in poultry production results in their accumulation in the body tissues and products such
as milk and egg. The subsequent accumulation of these drugs and their metabolites in body cells is known as drug residue.
This study was designed to determine the prevalence of antimicrobial residues in eggs from poultry farms and retail outlets
in Enugu State, Nigeria. Eggs from 25 selected commercial farms and ten retail outlets were screened for the prevalence of
antimicrobial residue. Also, structured questionnaires were administered to 25 commercial farms in the state to determine
the management practices and the most widely used antimicrobial drugs in farms and possible association between the management
practices and the occurrence of antimicrobial residues in eggs from these farms. All the 25 farms surveyed use oxytetracycline.
Eggs from nine of the surveyed farms tested positive for antimicrobial residue and three of the ten surveyed farms also tested
positive for antimicrobial residue. No association was observed (p 0.05; Fisher’s exact test) between the occurrence of antibiotic residues in eggs and farm size, feed source and housing systems.
This study was able to demonstrate the presence of antimicrobial residues in eggs destined for human consumption. Drugs like
nitrofurans which has been banned for use in food animals are still very much in use in Enugu State, Nigeria. Antibiotics
given as feed additives may give rise to drug residues in food animals. 相似文献
19.