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1.
Effects of β‐cyclodextrin diallyl maleate (CD‐M) on methane production, ruminal fermentation and digestibility were studied both in vitro and in vivo. In in vitro study, diluted ruminal fluid (30 mL) was incubated anaerobically at 38°C for 6 and 24 h with or without CD‐M using hay plus concentrate (1.5:1) as a substrate. The CD‐M was added at different concentrations (0, 1.25, 2.5, 5.0 and 7.5 g/L). The pH of the medium and numbers of protozoa were not affected by the addition of CD‐M. Total volatile fatty acids were increased and ammonia‐N was decreased, molar proportion of acetate was decreased and propionate was increased (P < 0.05) by CD‐M. Methane was inhibited (P < 0.05) by 14–76%. The effect of CD‐M on methane production and ruminal fermentation was further investigated in vivo using four Holstein steers in a cross‐over design. The steers were fed Sudangrass hay and concentrate mixture (1.5:1) with or without CD‐M (2% of feed dry matter) as a supplement. Ruminal proportion of acetate tended to decrease and that of propionate was increased (P < 0.05) 2 h after CD‐M dosing. Total viable counts, cellulolytic, sulfate reducing, acetogenic bacteria and protozoa were unaffected while methanogenic bacteria were decreased (P < 0.05) by CD‐M. The plasma concentration of glucose was increased, whereas that of urea‐N was decreased (P < 0.05). Methane was inhibited (P < 0.05) from 36.4 to 30.1 L/kg dry matter intake by the addition of CD‐M. Apparent digestibilities of dry matter and neutral detergent fiber were not affected while that of crude protein was increased (P < 0.05) in the medicated steers. These data suggested that dietary supplementation of CD‐M decreased methane production and improved nutrient use.  相似文献   
2.
The effects when adding cyclodextrin‐iodopropane complex (CD‐IP) to a diet, on ruminal fermentation and microbes, digestibility, blood metabolites and methane production, were evaluated using four Holstein steers in a cross‐over design. The steers were fed Sudangrass hay plus concentrate mixture at a ratio 1.5:1, and CD‐IP (1% of dry matter) was given twice daily by mixing with concentrate mixture. Rumen and blood samples were collected at 0, 2, and 5 h after morning dosing. Ruminal pH and numbers of protozoa were unaffected by CD‐IP treatment. Ruminal molar proportion of acetate was decreased (P < 0.05), and propionate was increased (P < 0.01) at 2 h after CD‐IP dosing. Proportion of butyrate was increased (P < 0.05) and ammonia‐N was decreased (P < 0.05) at 2 and 5 h after CD‐IP dosing. Adding CD‐IP had no effect on the feed intake and digestion of nutrients. Plasma glucose was increased and urea‐N was decreased (P < 0.05) at 2 and 5 h after CD‐IP dosing. Methane production was decreased (P < 0.05) by approximately 18% in the treatment steers. Numbers of methanogenic bacteria were decreased (P < 0.05), while total viable counts, cellulolytic, sulfate reducing and acetogenic bacteria were unaffected. The present results are the first to show that CD‐IP can partially inhibit in vivo ruminal methanogenesis without adverse effects on digestion of nutrients.  相似文献   
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Plasma N-terminal pro-atrial natriuretic peptide (NT-proANP) concentration increases with progression of myxomatous mitral valve disease (MMVD) in dogs. This multicentre, prospective study compared plasma NT-proANP, N-terminal pro-brain natriuretic peptide (NT-proBNP), ANP, and cardiac troponin I (cTnI) concentrations in dogs with MMVD for their characteristics and discriminatory ability to detect cardiac dilatation and congestive heart failure (CHF). Thirty-six healthy dogs and 69 dogs with MMVD were included. Clinical variables were obtained via physical examination, thoracic radiography, and echocardiography. The discriminatory ability of each cardiac biomarker (CB) to determine the presence or absence of cardiac dilatation (event 1) and CHF (event 2) was evaluated using the receiver operating characteristic curves. Plasma NT-proANP, NT-proBNP, and ANP concentrations showed a significant association with the left atrium/aorta ratio (P<0.01). The area under the curve of plasma NT-proANP and NT-proBNP concentrations were 0.72 and 0.75, respectively in event1 and 0.72 and 0.76, respectively in event2. Plasma NT-proANP and NT-proBNP concentrations showed sensitivity 80.0 and 80.0%; specificity 67.6 and 64.7% in event1 (cutoff value; 8,497.81 pg/ml and 1,453.00 pmol/l, respectively) and sensitivity 85.7 and 81.0%; specificity 60.4 and 64.6% in event2 (cutoff value; 8,684.33 pg/ml and 1,772.00 pmol/l, respectively). In dogs with MMVD, plasma NT-proANP, NT-proBNP, and ANP concentrations increase with left atrial enlargement. Particularly, plasma NT-proANP and NT-proBNP concentrations appeared to be equally useful in the discriminatory ability to detect cardiac dilatation and CHF.  相似文献   
5.
Quantities and types of ceramides and their relationships to physical properties of the horn covering the claws of clinically normal cows and cows with subclinical laminitis were investigated. Total ceramide content of the horn covering the sole and wall from cows with subclinical laminitis was 872.2 +/- 146.6 microg/g and 528.6 +/- 61.3 microg/g, respectively, and was significantly (P < 0.01, 0.05) lower than that from clinically normal cows. The mean moisture content in the claws from cows with subclinical laminitis (43.5% +/- 4.3%) was significantly (P < 0.05) higher than that in the claws from clinically normal cows. The hardness of claws from cows with subclinical laminitis (35.2 +/- 3.5) was significantly (P < 0.05) less than that of claws from clinically normal cows. Significant correlations between ceramides and moisture content (P < 0.001) and between ceramide and hardness (P < 0.001) were found in clinically normal cows and cows with subclinical laminitis. Our results indicate that decreases in ceramide contents may be related to changes in physical properties of the horn covering the claw in cows with subclinical laminitis.  相似文献   
6.
Progesterone plays important roles in the regulation of female reproduction. In this study, progesterone receptor (PR) mRNA levels in rat uterus during pregnancy, labor, lactation and the estrous cycle were examined by competitive RT-PCR. During pregnancy and lactation, PR mRNA levels had decreased on day 20 of pregnancy (P20) and P21 compared with P15 but increased during labor. After a decline on day 1 of lactation (L1), PR mRNA levels had increased again on L3 and L14 compared with P15, P18, P20, P21 and P21pm (at 2200-2300 h on P21). There was no significant change in the PR mRNA level during the estrous cycle. The PR mRNA level did not change during 1 week of progesterone treatment or afterwards. Injection of 17beta-estradiol did not affect PR mRNA levels in rats treated with progesterone or those without any injections. In rats on P18, 17beta-estradiol injection did not change PR mRNA levels after sham-operation but induced an increase in PR mRNA levels of rats ovariectomized 6 h before the treatment. These results suggest that uterine PR mRNA levels are differently regulated during late pregnancy, labor and lactation, and during labor estrogen is one of the essential factors for the increase in PR mRNA levels.  相似文献   
7.
Oxytocin receptor (OTR) mRNA levels increase dramatically near term and is potently stimulated by estrogen because increased OTR mRNA levels result from estrogen treatment in ovariectomized rat uterus. In this study, OTR, estrogen receptor (ER) alpha and ERbeta mRNA levels in the rat uterus during the estrous cycle were examined by quantitative RT-PCR. OTR mRNA levels during the estrous cycle began to increase on diestrus (P<0.05, vs value on estrus), reached maximal increase both in the morning (1000-1130 hr) and afternoon (1600-1630 hr) on proestrus (P<0.01, vs metestrus, diestrus and estrus) and then declined on estrus. In contrast ER alpha mRNA levels began to decrease on diestrus, reached statistical significance both in the morning and the afternoon on proestrus (P<0.01, vs metestrus, diestrus and estrus) and returned to the value of metestrus on estrus. ERbeta mRNA levels were low in the morning and the afternoon on proestrus (P<0.01, vs metestrus and estrus) and also returned to metestrus values on estrus. Treatments with estrogen for 3 days significantly decreased both ERalpha and ERbeta mRNA levels. It can be concluded from these results that during the estrous cycle, OTR mRNA levels in rat uterus predominantly increase at proestrus with a decrease in ERalpha and ERbeta mRNA levels, which is probably due to the increased estrogen levels in circulation before ovulation.  相似文献   
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ABSTRACT It has been speculated that the N-terminal half of the readthrough domain (RTD) encoded by open reading frame 5 of Soybean dwarf virus (SbDV) is related to the vector specificity. To further investigate this hypothesis, transmissibility via aphids was tested on 17 SbDV isolates and comparisons of the deduced amino acid sequences of the coat protein (CP) and other proteins encoded by the RTD were made between these isolates. Isolates were distinguished into four strains: YS, causing yellowing in soybean and transmittable by Aulacorthum solani; DS, causing dwarfing and transmittable by A. solani; YP, causing yellowing and transmittable by Acyrthosiphon pisum; and DP, causing dwarfing and transmittable by A. pisum. Phylogenetic analysis showed that the trees for the CP and the C-terminal half of the RTD sequences contained clusters of isolates of the same symptom type, whereas the tree for the N-terminal half of the RTD contained clusters of isolates of the same aphid vector type. These results agreed with our previous data of the complete nucleotide sequences of four SbDV isolates, and strongly indicated a close relationship between the N-terminal half of the RTD amino acid sequences and aphid transmission specificity of SbDV.  相似文献   
10.
OBJECTIVE: To develop polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis for molecular typing of strains of Streptococcus zooepidemicus and to use the new typing method to analyze a collection of isolates from the respiratory tract of Thoroughbreds. SAMPLE POPULATION: 10 strains of S zooepidemicus, 65 isolates from the respiratory tract of 9 yearlings following long distance transportation, and 89 isolates from tracheal aspirates of 20 foals with pneumonia. PROCEDURE: Phenotypic variations in the SzP protein were detected by western immunoblot analysis. Using PCR-RFLP analysis, genotypes were obtained with primer sets from the SzP gene, followed by restriction endonuclease digestion of the amplicons. RESULTS: Unique genotypic patterns were obtained with a primer set designed from both ends of the structural gene and the restriction endonuclease DdeI. Forty-five isolates from the lymphoid tissue within the pharyngeal recess (ie, pharyngeal tonsil) of yearlings included 10 SzP genotypes and SzP phenotypes. Isolates from the trachea of each yearling were of a single genotype that was also present among isolates from the pharyngeal tonsil of the same horses. Isolates from tracheal aspirates of foals belonged to 14 genotypes. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of the SzP gene by use of PCR-RFLP was effective for molecular typing of strains of S zooepidemicus in the study of respiratory tract disease in horses. Results of PCR-RFLP analysis indicate that a single strain of S zooepidemicus can migrate from the pharyngeal tonsil to the trachea at a high rate in horses undergoing long distance transportation.  相似文献   
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