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781.
The accurate identification of mastitis‐causing bacteria assists in effective management by both dairy farmers and veterinarians and can be used to implement the selective use of antimicrobials for treatment. The purpose of this study was to evaluate the ability of our developed anti–ribosomal protein-L7/L12 antibody–coated immunochromatographic strip (ICS) test to detect coliforms in milk by comparing the results with the bacteriological culture method. We investigated the performance of the ICS test as compared with the bacteriological culture method using 308 milk samples from clinical bovine mastitis. First, to determine the optimal ICS test cutoff point for detecting coliform mastitis, we developed a receiver-operating characteristic curve. The result showed that the cutoff point was at 0.5 of our index. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value of the ICS test were 81.3%, 84.8%, 69.2%, and 91.54%, respectively. As the clinical signs increased in severity, the F-measure, a weighted harmonic mean of the sensitivity and overall PPV performance, increased. Because it is especially important to treat clinical mastitis appropriately in the early stages of detection, the ICS test, which can be used by both dairy farmers and veterinarians on dairy farms, is considered to be a useful tool for detecting coliform mastitis, which often presents with severe signs.  相似文献   
782.
An adult male white eared-pheasant (Crossoptilon crossoptilon) at a Japanese zoo exhibited lethargy and emaciation. Microscopic examination of a blood smear revealed a haemosporidian parasitic infection. Based on the morphological characteristics and molecular analysis of the parasite, it was identified as Plasmodium (Bennettinia) juxtanucleare. This is the first report of P. juxtanucleare infection in bird species belonging to the genus Crossoptilon. Caution against avian malaria infection is required for the conservation of endangered bird species in zoos.  相似文献   
783.
The previously evaluated prototype, methyl 6-acetyl-2-[(4,6-dimethoxypyrimidin-2-yl)oxy]benzoate, was modified by the introduction of an oximino group. Further extensive synthetic modifications were then made to the 6-alkyl moiety (R1), the ester moiety (R2), the alkoxyimino moiety (R3), the bridge-atom (X) and the 4,6-disubstituted-pyrimidine moiety (A, B, Z). Structure–activity relationships of the synthesized compounds were studied by examining their herbicidal activity against Barnyard grass (Echinochloa oryzicola) in paddy rice at various growth stages, including pre-emergence. The novel herbicide methyl 2-[(4,6-dimethoxypyrimidin-2-yl)oxy]-6-[1-(methoxyimino)ethyl]benzoate, (KIH-6127) was found to be the most effective compound. The commercial development of this compound is currently in progress. © 1997 SCI.  相似文献   
784.
The effects of environmental temperature (21 vs. 28°C) during rice seed development on the starch characteristics (apparent amylose content, amylopectin chain length distribution, and gelatinization properties) of nonwaxy Taichung 65 (T65), waxy Taichung (T65wx), du2‐2 mutated low‐amylose strain Taichung (76‐3/T65), and Koshihikari were studied. Amylose contents increased with decreasing environmental temperatures. Analysis of the amylopectin chain length distribution showed that the relative amounts of long chains with degree of polymerization (DP) > 25 in all starches decreased if maturation occurred at 21°C. Gelatinization onset, peak, and conclusion temperatures and enthalpies decreased with decreasing environmental temperatures. Of all starches studied, the du2‐2 mutated low‐amylose Taichung (76‐3/T65) was most affected by maturation temperatures. These results indicate that the du2‐2 mutated low‐amylose Taichung (76‐3/T65) may be a useful strain in understanding biochemical and genetic starch biosynthesis response to slight changes in temperature.  相似文献   
785.
The aim of this study was to estimate genetic parameters for superovulatory response traits in order to explore the possibility of genetic improvement in Japanese Black cows. We analyzed 19 155 records of the total number of embryos and oocytes (TNE) and the number of good embryos (NGE) collected from 1532 donor cows between 2008 and 2018. A two-trait repeatability animal model analysis was performed for both. Because records of TNE and NGE did not follow a normal distribution, the records were analyzed following no, logarithmic, or Anscombe transformation. Without transformation, the heritability estimates were 0.26 for TNE and 0.17 for NGE. With logarithmic transformation, they were 0.22 for TNE and 0.18 for NGE. With Anscombe transformation, they were 0.26 for TNE and 0.18 for NGE. All analyses gave similar genetic correlations between TNE and NGE, ranging from 0.60 to 0.71. Spearman’s rank correlation coefficient between breeding values of cows with more than 10 records was ≥0.95 with both transformations. Thus, the genetic improvement of TNE and NGE of donor cows could be possible in Japanese Black cattle.  相似文献   
786.
Rusni  Suhaila  Sassa  Mieko  Takehana  Yusuke  Kinoshita  Masato  Inoue  Koji 《Fisheries Science》2020,86(4):605-613
Fisheries Science - Cytochrome P450 1A (Cyp1a) catabolizes polycyclic organic compounds. In this study, we sequenced the cyp1a gene from two Javanese medaka Oryzias...  相似文献   
787.

To understand the detoxification and bioactivation mechanisms for organic contaminants, it is essential to identify the cytochrome P450 (CYP) complement. Therefore, this study aimed to clone a partial cDNA sequence of the novel CYP1D1 gene from the fish Oreochromis niloticus and examine whether intraperitoneal injection of benzo-a-pyrene (BaP), a potent AHR agonist, is capable of inducing CYP1D1 mRNA expression in different tilapia fish tissues. The cloned nucleotide sequence consisted of 713 bp representing a portion of the tilapia CYP1D1 cDNA ORF, encoding 237 amino acids. Amino acid sequence comparison of O. niloticus CYP1D1 with the sequences of CYP1D1 from other species showed that this gene shared the highest identity of 81% with Fundulus heteroclitus CYP1D1. Furthermore, analysis of the percent identities shared by the deduced amino acid sequence of O. niloticus CYP1D1 with the sequences of CYP1 from other species revealed that the highest identities were shared with fish CYP1As. Real-time PCR results revealed that the highest expression level of CYP1D1 mRNA was found in muscles, followed by gills, liver, and intestine, while there was no detectable expression recorded in bile acid. These results indicate that tilapia CYP1D1 plays an important role in the metabolism of xenobiotics, expanding our knowledge regarding the diversity of CYP1 genes in this important model fish species.

  相似文献   
788.
Inoue  Satoko  Yasunaga  Genta  Pastene  Luis A. 《Fisheries Science》2019,85(6):971-977
Fisheries Science - The utility of progesterone concentration in blubber as a means of determining reproductive status in the Antarctic minke whale Balaenoptera bonaerensis was assessed through a...  相似文献   
789.
Pseudotuberculosis is a bacterial septicaemia caused by Photobacterium damselae subsp. piscicida in several marine fish species. Yellowtail Seriola quinqueradiata is the most sensitive fish species to this disease. The internal organs of naturally infected yellowtail exhibit whitish spots, tubercle-like tissue structures, consisting of bacterial accumulations. There have been many trials for experimental infection, however adequate method of infection that reproduces moderate mortality and primary clinical signs has not yet established. Present investigation evaluated an immersion infection method by using logarithmic culture-phase bacteria resulting in higher mortality than that using stationary culture-phase bacteria. Typical white spots on the spleen and kidney were also observed constantly in dead fish. Transmission electron microscopy and fluorescent antibody microscopy showed bacterial clusters not only in the spleen and kidney but also in the blood channels in the secondary gill filaments. These results were confirmed repeatedly by plural experiments. The use of logarithmic-phase bacteria in immersion infection is an appropriate technique to reproduce moderate mortality and primary clinical signs, which will be a reliable infection method also for the challenge test of pseudotuberculosis vaccine.  相似文献   
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