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ABSTRACT:   Mottled amago salmon Oncorhynchus masou ishikawe with both yellow- and dark-pigmented skin occurred together with typical albino individuals in a commercial farm. Out of 12 mottled fish examined by DNA content flow-cytometry and erythrocytic nucleus size, three were diploid, eight were haploid-diploid mosaic and one was diploid-triploid mosaic. This fact indicates that the mottled coloration might link to polyploid mosaicism. Genotype of diploid and non-diploid cells at the albino locus was estimated in nine mature mottled fish by observing the frequency of wild-type and albino progeny when mating to homozygous albino ( aa ). One diploid and three haploid-diploid mosaic mottled fish were presumed to have mosaic genotype with both hemizygous ' a ' and heterozygous ' Aa ' cells ( a/Aa ), because the segregation ratio between two phenotypes was 1 : 1. Three other haploid-diploid mosaic fish were presumed to have mosaic genotype with both hemizygous ' a ' and homozygous ' AA ' cells ( a/AA ), because of exclusive occurrence of wild-type phenotype in the progeny. The diploid-triploid mosaic mottled fish was presumed to have mosaic genotypes ' aa / AAA ', ' aa/AAa ' or ' aa / Aaa ', because this fish yielded only albino progeny. One diploid mottled fish produced both two phenotypes but albino embryos appeared with much more frequency than the expectation, when assuming the genotype ' Aa '. Thus, this fish was considered to have mosaic genotype ' Aa/aa '.  相似文献   
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A consumer questionnaire conducted with the purpose of ascertaining the acceptability of goat milk and related products in Japan was carried out on 345 guarantees of Nippon Veterinary and Life Science University in December 2006. 275 effective responses (79%) representing middle class urban households were returned. The results revealed that (1) 30% of respondents have experienced drinking goat milk and only 10% are aware of the current retail situation of goat milk and related products; (2) over 70% of goat milk drinkers raised goats by hand at some point in their past and their first experience drinking goat milk was in infancy; (3) those with experience in drinking goat milk expressed a vague evaluation and minimal understanding of drinking goat milk; (4) respondents who were inexperienced goat milk drinkers expressed a strong desire to taste and a weak desire to purchase goat milk; (5) respondents expressed low recognition regarding retailed goat milk products, but those who had already purchased goat milk products expressed a high evaluation and strong desire to purchase these products again; and (6) recognition of goat milk characteristics is low, but those with high recognition also rate goat milk highly. Goats are perceived as being 'mild and familiar.' It is necessary for those who manage goat husbandry to present goat milk and related product tasting opportunities to consumers. The key point is to make the functional differences between cow and goat milk clear and present the advantages of goat milk at the fore of this promotion. Goat milk should not be promoted merely as a drink that is similar to cow milk, but must be positioned as a functional drink or health food in order to expand the Japanese goat milk market.  相似文献   
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Soybeans contain oil bodies that are coated by a layer of oleosin proteins. In nature, this protein coating protects the oil bodies from environmental stresses and may be utilized by food manufacturers for the same purpose. In this study, oil bodies were extracted from soybean using an aqueous extraction method that involved blending, dispersion (pH 8.6), filtration, and centrifugation steps. The influence of NaCl (0-250 mM), thermal processing (30-90 degrees C, 20 min) and pH (2-8) on the properties and stability of the oil bodies was analyzed using zeta-potential, particle size, and creaming stability measurements. The extracted oil bodies were relatively small ( d 32 approximately 250 nm), and their zeta-potential went from around +12 mV to -20 mV as the pH was increased from 2 to 8, with an isoelectric point around pH 4. The oil bodies were stable to aggregation and creaming at low (pH = 2) and high (pH >/= 6) pH values but were unstable at intermediate values (3 相似文献   
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Hepatocyte growth factor/scatter factor (HGF/SF) is a pleiotropic cytokine that plays a crucial role in the embryonic and postnatal development of various organs including the mammary gland. We cloned bovine HGF and its c-Met receptor cDNAs, and examined their expression during mammary gland development in dairy cows. The 2.5-kbp HGF cDNA clone contained a 2190 bp open reading frame coding a 730 amino acid protein, while the 4.8-kbp c-Met cDNA clone contained a 4152 bp open reading frame coding a 1384 amino acid protein. The bovine HGF and c-Met sequences exhibited more than 87% identity with those of other mammals. RT-PCR analysis revealed ubiquitous expression of both HGF and c-Met mRNAs in various bovine tissues tested. HGF mRNA was detected only in the inactive stage of bovine mammary gland development and not in the developing, lactating, and involuting stages, while c-Met mRNA was detected in the inactive and involuting stages. Immunohistochemical analysis demonstrated that the c-Met protein was found on mammary epithelial cells in the inactive, developing, and involuting stages, and on myoepithelial cells in all stages. These results suggest pivotal roles of HGF and c-Met in the development of bovine mammary gland.  相似文献   
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Lulu is a dwarf cattle population bred in the Mustang district of western and central Nepal. This area is located around the habitat boundary between Bos taurus and Bos indicus. The peculiarities of Lulu are their small size (weight range in the adult female: 68–153 kg) and rearing in high mountain areas at 2800 m to 4000 m in altitude. There were 5770 head of Lulu cattle in the Mustang district in 1998, 4333 females and 1437 males. The morphological appearance of Lulu is Bos taurus. However, one of the five Lulu studied in Kagbeni, Mustang had a Bos indicus mitochondrial DNA type based on the D‐loop sequence, while the other four were Bos taurus. It is suggested that there are hybrids of Lulu with Bos indicus maternal lineage in a mostly taurine‐breed genetic background. Steps must be taken to preserve the unique Lulu.  相似文献   
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A total of 80 free-roaming dogs on Okinawa Island, Japan, were examined for Babesia infection using the polymerase chain reaction (PCR) and sequence analysis. Of 80 samples, 12 were positive in a Babesia genus-specific PCR. Consequent species-specific PCR for B. canis and B. gibsoni revealed that 5 (6.3%) and 7 (8.8%) dogs were infected with B. canis and B. gibsoni, respectively. Sequence analysis of the PCR products revealed that the 18S rRNA gene sequence of B. canis detected from dogs in Okinawa was very close to B. canis vogeli with sequence similarity of 99.94%.  相似文献   
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