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1.
We estimated the genetic parameters of fat‐to‐protein ratio (FPR) and the genetic correlations between FPR and milk yield or somatic cell score in the first three lactations in dairy cows. Data included 3 079 517 test‐day records of 201 138 Holstein cows in Japan from 2006 to 2011. Genetic parameters were estimated with a multiple‐trait random regression model in which the records within and between parities were treated as separate traits. The phenotypic values of FPR increased soon after parturition and peaked at 10 to 20 days in milk, then decreased slowly in mid‐ and late lactation. Heritability estimates for FPR yielded moderate values. Genetic correlations of FPR among parities were low in early lactation. Genetic correlations between FPR and milk yield were positive and low in early lactation, but only in the first lactation. Genetic correlations between FPR and somatic cell score were positive in early lactation and decreased to become negative in mid‐ to late lactation. By using these results for genetic evaluation it should be possible to improve energy balance in dairy cows.  相似文献   
2.
ABSTRACT:   Recently, a serious disease spread extensively in aquaculture sites of the ascidian Halocynthia roretzi in Korea. To understand circumstances of ascidians in Korean aquaculture sites, residue levels of organotin compounds were analyzed, and detection of a marine birnavirus (MABV) in tissues of H. roretzi was attempted. Korean H. roretzi showed high concentrations of butyltins (mono, di, and tributyltins), especially in the gill, hepatopancreas, and digestive tract. However, there was no significant difference in the residues of butyltins in the hepatopancreas between diseased and non-diseased ascidians. The positive rate of MABV detection was high in the hepatopancreas, but also no significant difference was observed between diseased and non-diseased individuals. These observations suggest that an accumulation of tributyltin and a latency of MABV in H. roretzi tissues does not directly relate to the occurrence of the disease.  相似文献   
3.
The duck growth hormone encoding gene and its promoter region were amplified by polymerase chain reaction (PCR). A total of 5.25 kb were cloned and sequenced. Duck growth hormone (GH) consists of five exons and four introns and is structurally similar to mammalian and chicken GH gene. Although the distal region of duck GH promoter showed no similarity to chicken and turkey promoters, the proximal region of the promoter contained two putative Pit‐1 binding sequences, and showed similarity to chicken and turkey GH promoters. Genetic variation was detected at five positions of the promoter region. The results of this study indicate that the expression of duck GH is likely regulated in a similar manner to that of chicken GH via enhancer‐type cis‐acting elements and the presence of genetic variation in the duck GH gene may be applicable to marker‐assisted selection.  相似文献   
4.
Intramammary infusion of Bifidobacterium breve (B. breve)-induced somatic cell (SC) counts, chemiluminescent response (CL), lactoferrin (LF) concentrations and mastitis-causing pathogens from quarters with subclinical mastitis were measured to evaluate innate immune response of mammary glands in dairy cows at 3 to 4 weeks before drying off. SC counts in 7 quarters of 7 control cows and 5 quarters of 6 cows with mastitis increased markedly on day 1 and SC values in control cows were significantly (P<0.05) increased and returned to pre-infusion levels on day 5 after B. breve-infusion. CL values in both groups increased markedly on day 1 and then decreased after B. breve-infusion; however, CL values in cows with mastitis did not return to normal levels on day 5 and at postpartum. The CL values were highly correlated with their SC counts in milk from both groups. LF concentrations increased toward day 3 after B. breve-infusion and were higher in cows with mastitis. B. breve-infusion eliminated 16.6% (1/6) of pathogens from 6 quarters with chronic subclinical mastitis. B. breve-induced SC responses in quarters from 3 cows with mastitis showed characteristic patterns of recovery, persistent and new infections. B. breve-induced SC counts in quarters from the cows in the pre-drying off were lower (25.7–70.6%) than those of the cows in mid-lactation. The intrinsic innate immune response in cows on pre-drying off may be decreased and appears to be insufficient to eliminate pathogens from mammary gland in the pre-drying off.  相似文献   
5.
Restriction fragment length polymorphic markers in the chicken growth hormone (GH) gene were tested for their association with egg production traits. Alleles of GH were determined in 3 non‐inbred strains from different genetic bases. The frequency of PS1 (+) allele in the three strains was very low in contrast to the layer strain previously reported. Results of the present study indicate that the frequency of PS (+) is related to egg production and that the PS1 (+) allele may be used as a genetic marker for selection in egg production.  相似文献   
6.

Invertebrates change the metabolite concentrations in their bodies to adapt to environmental salinity. The kuruma shrimp Marsupenaeus japonicus is one such invertebrate. It lives in coastal areas and is also known to change free amino acid concentrations depending on environmental salinity. To examine the relationship between the concentrations of metabolites, including amino acids, in the kuruma shrimp with environmental salinity, metabolome analysis was performed on the abdominal muscle of shrimps acclimated at 17, 34 and 40‰ salinity for 24 h. Principal component analysis revealed that the accumulation patterns of metabolites using the 111 metabolites detected in the shrimps exposed to different salinities were depicted in a salinity-dependent manner. The concentrations of alanine and glutamine were increased following exposure to increasing levels of salinity, suggesting that these free amino acids function in intracellular osmoregulation of the kuruma shrimp. Furthermore, the concentration of glycolytic metabolites was significantly decreased at high salinity. The concentrations of most of the metabolites related to the tricarboxylic acid (TCA) cycle also tended to decrease at high salinity. Considering the levels of expression of the genes related to various metabolic pathways, it seems that glycolysis is accelerated at high salinity.

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7.
Increasing herd‐life length and culling parity with increasing conception rate (CR) is necessary to increase lifetime profit from dairy cow production. Economic values of days open (DO) were determined by calculating changes in fertility traits, herd‐life length, and milk yield when the simulated CR were changed in increments of 1% from ?5% to 5% from the basal levels, which were obtained for Hokkaido and regions other than Hokkaido separately. When CR increased, number of artificial inseminations, DO, and milking length decreased. Furthermore, culling parity, and annual milk yield increased. Herd‐life length increased in Hokkaido and decreased in the other regions. The economic values of CR were 1,623.8 to 946.8 yen and of DO were 857.4 to 399.0 yen. Relative economic values of milk yield to days open per genetic standard deviation were higher in the other regions than in Hokkaido where the economic effect of selection for DO was expected to be equal to selection for 305‐day milk yield and herd life. If the survival rate of multipara cows in the other regions increases, then the economic value of DO would similarly increase in Hokkaido.  相似文献   
8.
9.
Characteristics such as flower form, size and color of outer and inner perianths, anthocyanins in outer perianths, size, color and fertility of pollen and self-fertility of diploid and tetraploid lines regenerated via protoplast culture of Iris fulva were examined and compared with those of the diploid wild line. Among these characteristics, flower form, inner and outer perianth sizes of the tetraploid lines were noticeable, because these lines had upward flower forms and bigger flowers than diploid lines. Furthermore, reciprocal crosses between diploid or tetraploid lines of I. fulva and I. ensata and those of I. fulva and I. laevigata were performed. Three seedlings were obtained from the cross of tetraploid I. fulva × diploid I. laevigata through embryo rescue. One of them was identified as the interspecific hybrid between tetraploid I. fulva and I. laevigata by flow cytometoric (FCM), cytological and molecular (RAPD) analyses. This is the first report on production of hybrids from these lines. I. fulva has unique brown flowers, and this trait could be very useful for flower color breeding of I. laevigata which lacks this color. Therefore, the hybrid of I. fulva (4×) × I. laevigata may be the best available gene source for brown color breeding of this species.  相似文献   
10.
Sawdusts of sugi (Cryptomeria japonica) wood prepared before and after steam drying at 120°C in a kiln were extracted with n-hexane and ethyl acetate to give n-hexane extracts and ethyl acetate extracts. From gas chromatography-mass spectrometry analysis of the ethyl acetate extracts from woods before and after steam drying, the components of 4-epi-cubebol, cubebol, and 2,7(14),10-bis-abolatrien-1-ol-4-one, which existed in the raw sugi wood, were proved to disappear in the steam-dried wood. These components were also absent in the ethyl acetate extract of the steam-condensed solution of waste steam from the kiln outlet. When these three components were treated with 0.2% (v/v) acetic acid solution at 120°C, δ-cadinene was produced as a major product from both 4-epi-cubebol and cubebol by dehydration and cleavage of the cyclopropane ring, and cryptomerone from 2,7(14),10-bisabolatrien-1-ol-4-one by hydration. The chemical changes of the three components presumably occur during steam drying of the sugi wood. This study was presented in part at the 85th Spring Meeting of the Chemical Society of Japan, Kanagawa, Japan, March 26–29, 2005  相似文献   
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