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为了掌握植物叶片中花色素苷含量对植物叶片PSⅡ功能的影响情况,以土庄绣线菊Spiraea pubescens、金焰绣线菊S.×bunmalba cv.Goldflame和金山绣线菊S.×bunmalba cv.Goldmound为试验材料,利用叶绿素荧光技术研究了花色素苷在绣线菊叶片光合机构中的作用。结果表明:三种绣线菊的完全展开叶片(即成熟叶片)中的花色素苷含量较低,叶绿素含量以及叶绿素荧光参数之间的差异较小;而在三种绣线菊的伸展叶片(生长叶片)中,金焰绣线菊和金山绣线菊叶片中花色素苷含量明显高于土庄绣线菊,而其叶绿素含量却明显低于土庄绣线菊。金焰绣线菊和金山绣线菊伸展叶片的初始荧光(Fo)、最大荧光(Fm)和单位反应中心吸收的光能(ABS/RC)均明显低于土庄绣线菊,说明较高含量的花色素苷降低了绣线菊叶片对光能的吸收,但是PSⅡ最大光化学效率(Fv/Fm)、PSⅡ潜在光化学活性(Fv/Fo)、电子传递速率(ETR)和实际光化学效率(ФPSⅡ)却明显高于土庄绣线菊。土庄绣线菊伸展叶片的有活性的PSⅡ反应中心数量明显低于金焰绣线菊和金山绣线菊,而单位反应中心吸收的光能(ABS/RC)、单位反应中心捕获的用于还原QA的能量(TRo/RC)、单位反应中心捕获的用于电子传递的能量(ETo/RC)和单位反应中心耗散掉的能量(DIo/RC)均明显高于金焰和金山绣线菊,且土庄绣线菊伸展叶片失活反应中心的比例较高。花色素苷不但改变了金焰绣线菊和金山绣线菊伸展叶片对光能的吸收,而且改变了光合电子的传递速率和能量分配参数,影响了绣线菊伸展叶片的PSⅡ功能。 相似文献
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To evaluate the effect of Spanish summer commercial journeys on the stress response of young bulls born and reared under extensive conditions, 2 replicates of a transport from an assembly centre to a growing-finishing farm were studied. Journeys lasted 27 h, involving a total of 62 young bulls. Variables under study included haematocrit, red blood cell count (RBC), total white blood cell count (WBC), differential WBC counts, serum haptoglobin (Hp), cortisol, glucose, creatine phosphokinase (CPK), lactate dehydrogenase (LDH), total protein, and albumin at loading, at the end of an intermediate market stop, and at the unloading. Before the beginning of the journey elevated WBC and neutrophil counts, and high Hp values were detected, reflecting high stress levels probably as a consequence of previous procedures associated with the grouping at the assembly centre. Some stress was also detected at the end of the market stop, with cortisol increasing from 6.5 to 12.6 ± 2.0 ng/mL (P < 0.001), although a change in Hp concentration was not observed. Neither CPK and LDH activities, related to muscular tissue damage, nor haematocrit and RBC count, related to dehydration revealed a significant effect of this first stage of the journey on the physical stress of the young bulls. Subsequent 13 h transport to the growing-finishing farm induced an increase in Hp levels from 0.48 to 0.78 ± 0.16 mg/mL (P < 0.001), reflecting an onset of the acute stress response, although cortisol levels immediately after the unloading were similar to those found before loading at the market, suggesting that calves got accustomed to transport. At the end of the journey some dehydration and physical stress were also detected. Overall, our study provides new information to the discussion of the effect of temperatures during cattle transport. Although an improvement in pre-transport conditions is essential if the welfare of assembled and transported cattle is to be improved, the stress-related alteration of cattle physiology under Spanish summer commercial transport conditions is similar to that observed under colder conditions. 相似文献
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The effect of feeding rate on the growth performance of green sturgeon (Acipenser medirostris) fry 
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下载免费PDF全文 Four one‐week growth trials were conducted on green sturgeon fry to determine the effect of feeding rate on their growth performance at 18 °C when they were fed a salmonid soft moist feeds containing 445–457 g kg?1 of crude protein and 201–207 g kg?1 of lipid. The fry used in Trials I‐IV were 5–8 weeks after their initiation of exogenous feeding. Their average initial body weights were 1.63 ± 0.01, 2.63 ± 0.03, 5.08 ± 0.08 and 7.49 ± 0.05 g, respectively. Six feeding rates used were as follows: 2.5–15.0% body weight per day (% BW day?1) with a 2.5% increment in Trial I; 1.25–7.50% BW day?1 with a 1.25% increment in Trial II; and 2.0–7.0% BW day?1 with a 1.0% increment in Trials III and IV. Four replicates with 50 fry per tank in Trials I‐III and 30 fry per tank in Trial IV were assigned randomly to each feeding rates. The final body weight, specific growth rate, feed efficiency, protein retention, and whole‐body moisture, lipid, and energy contents were significantly (P < 0.05) affected by the feeding rates. The optimum feeding rates determined by the broken‐line model were 7.1, 5.7 and 5.3% BW day?1 for Trials I, II and IV, when the fry were 5, 6 and 8 weeks after their initiation of exogenous feeding, respectively. 相似文献
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Bovera F Moniello G De Riu N Di Meo C Pinna W Nizza A 《Tropical animal health and production》2007,39(4):265-270
In order to study the metabolic profile of ostriches in relation to diet, 40 animals of both sexes were divided equally into
two groups and fed two diets ad libitum consisting, on a dry matter basis, of the same commercial concentrate (60%) for the two groups and of corn silage (group
A) or alfalfa hay (group B). In the morning, after about 12 h of fasting, blood was collected from the wing vein. The following
haematological parameters were determined with an automatic system (Ektachem 250 analyser, Kodak): glucose, cholesterol, triglycerides,
lactate (LAC), total protein (TP), uric acid, total bilirubin (Tbil), creatinine (CREA), calcium (Ca), magnesium (Mg), phosphorus
(P), sodium (Na), potassium (K), chloride (Cl−), iron (Fe), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), cholinesterase
(ChE), α-amylase (Amyl), lipase (LIP) and γ-glutamyltrasferase (GGT). Diet significantly affected some parameters of the metabolic
profile. Indeed, owing to the presence of alfalfa hay in the diet, group B showed, in comparison to group A, significantly
higher values of uric acid (222.5 vs 387.5 mmol/L, p < 0.01), GGT (8.50 vs 11.3 U/L, p < 0.05), Tbil (8.50 vs 10.7 mmol/L, p < 0.05), Ca (2.41 vs 2.83 μmol/L, p < 0.01), Mg (1.01 vs 1.18 μmol/L, p < 0.05) and K (2.71 vs 3.16 μmol/L, p < 0.01). The levels of creatinine (27.3 vs 32.6 mmol/L, p < 0.05) and AST (344.9 vs 461.4 U/l, p < 0.01) were also higher for group B. 相似文献
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Lee KS Kim EY Jeon K Cho SG Han YJ Yang BC Lee SS Ko MS Riu KJ Lee HT Park SP 《The Journal of reproduction and development》2011,57(1):127-134
The effects of two antioxidants, superoxide dismutase (SOD) and the flavonoid 3,4-dihydroxyflavone (DHF), on bovine embryo development in vitro were examined. Blastocyst development, total cell and inner cell mass (ICM) numbers, intracellular levels of reactive oxygen species (ROS), apoptotic indices and gene expression levels were examined before and after treatment of day 2 bovine embryos (≥2-4 cells) with various concentrations of 3,4-DHF or SOD for 6 days. Statistical analysis was performed using analysis of variance, with significance defined at the P<0.05 level. SOD had no significant effect on bovine embryo development at any tested concentration (control, 32.8%; 300 U/ml, 33.9%; 600 U/ml, 24.2%). In contrast, 10 μM 3,4-DHF promoted higher blastocyst development (39.3%) than any other concentration (control, 26.7%; 1 μM, 30.3%; 50 μM, 29.5%; 100 μM, 20.5%). Compared with 300 U/ml SOD, 10 μM 3,4-DHF resulted in significantly higher blastocyst development (44.2%) (control, 31.5%; SOD 300 U/ml, 33.6%). Treatment with 3,4-DHF increased the ICM cell number and reduced intracellular ROS production and apoptotic cell numbers. When O(2) tension was decreased from 20% (high tension) to 5% (low tension), embryo development rates were doubled regardless of 3,4-DHF treatment. Under high O(2) tension, 10 μM 3,4-DHF treatment may render bovine embryo development similar to a low O(2) tension environment. The best blastocyst development was obtained under low O(2) tension plus 10 μM 3,4-DHF treatment. The relative expression levels of antioxidant (MnSOD), antiapoptotic (Survivin, Bax inhibitor) and growth-related genes (IFN-τ, Glut-5) were significantly increased after 3,4-DHF treatment, while the expression levels of oxidant (Sox) and apoptotic genes (Caspase-3 and Bax) were reduced. These results suggest that 3,4-DHF may promote the in vitro development of bovine embryos through its antioxidant and antiapoptotic effects. 相似文献
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Kim EY Lee JB Park HY Jeong CJ Riu KZ Park SP 《The Journal of reproduction and development》2011,57(3):346-354
Embryonic stem (ES) cells are expanded versions of the inner cell mass cells that compose the early mammalian blastocyst. Components derived from ES cells may contain various bioactive materials (BM) helpful for early preimplantation embryo growth. In this study, we examined the effect of human ES cell derived BM (hES-BM) on in vitro culture of bovine embryos. When bovine parthenogenetic day 2 embryos were cultured in 10% hES-BM, a significantly higher embryo development rate (44.3%) and increased cell numbers were observed relative to control medium containing 3 mg/ml BSA (19.5%; P<0.01). Among the various concentrations (5, 10 and 15%) and days of treatment (2 or 4 days) tested, 10% hES-BM treatment for 4 days provided the best culture environment to support the growth of bovine embryos in vitro (P<0.05). Little difference was observed between 10% hES-BM and 10% FBS treatment in the examined parthenogenetic or in vitro fertilized embryos, although the hES-BM group developed at a slightly better rate. However, the ICM cell numbers were significantly higher in the hES-BM group in irrespective of embryo origin (P<0.05). In addition, the relative levels of pluripotency (Oct4, × 1.8 fold; Nanog. × 3.3 fold), embryogenesis (Stat3, × 2.8 fold; FGF4, × 18.8 fold; E-cad, × 2.0 fold) and growth (Glut5, × 2.6 fold) genes were significantly higher in the 10% hES-BM group than in the 10% FBS group (P<0.05), while the levels of other genes (Bax, Bcl2, MnSOD and Connexin43) were not different. This is the first report examining the positive effects of hES-BM on bovine embryo development in vitro. Based on our results, we conclude that hES-BM can be used as a new protein supplement for bovine preimplantation embryo development. 相似文献
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RT Kridli AY Abdullah M Momani Shaker KZ Mahmoud 《Reproduction in domestic animals》2008,43(4):497-501
The objective of the study was to compare sexual performance of pure and crossbred rams, and to evaluate whether prior exposure of rams to short-tailed females would enhance their mating ability when later exposed to fat-tailed females. Twenty-two virgin, yearling Awassi (A; n = 7), F1 Charollais × Awassi (CA; n = 7) and F1 Romanov × Awassi (RA; n = 8) rams were subjected to sexual performance tests on six 20-min occasions. Each ram was individually exposed to two short-tailed oestrous ewes for three 20-min occasions on three consecutive days. Following 1 day of rest, the same 3-day procedure was repeated for each ram with fat-tailed ewes. Leg kicking bout frequency increased in CA and RA rams and decreased in A rams, when they were exposed to fat-tailed compared with short-tailed ewes. No differences in anogenital sniffing were observed among rams exposed to either short-tailed or fat-tailed ewes. However, greater (p < 0.001) anogenital sniffing bouts were recorded, when rams were exposed to short-tailed females. Upon exposure to fat-tailed ewes, CA and RA rams experienced a marked increase in mounting frequency compared with a slight increase in mounting of A rams (p < 0.001). The ability of Awassi rams to raise the fat tail of Awassi ewes was greater (p < 0.001) than CA and RA rams. Mating was improved in A while declining in CA and RA, when they were exposed to fat-tailed compared with short-tailed ewes (p < 0.001). Based on the results of the current study, it seems that all yearling rams were capable of mating with short-tailed ewes, whereas only Awassi rams managed to mate with fat-tailed ewes. It appears that brief exposures of yearling crossbred rams to short-tailed ewes do not improve their mating ability when later exposed to fat-tailed ewes. 相似文献
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新世纪农业科技园区体制建设中存在问题与对策的探讨 总被引：1，自引：0，他引：1
针对农业科技园区体制建设方面的不足,对农业科技园区在管理体系的建立,政府的职能定位,政府、中介、企业、农民的关系等方面进行了初步探讨。 相似文献
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