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1.
Two mungbean varieties, Guj-1 and PIMS-1 differing in their productivity potential, were examined to investigate their photosynthetic system at various stages of growth in relation to yield with two different dates of sowing. Vertical leaves were found to be beneficial. On the other hand, excessive leaf area during the later stages of growth may be detrimental to yield. Lower LAD at seedling stage and overall high NAR values may be reflected in higher grain yield. NAR declined as season progressed and this, in turn, may be related with increase in LAI. The grain yield was considerably more at the first date of sowing as compared to second date of sowing, the effect was being more pronounced in var. PIMS-1 . Various environmental factors recorded at two different dates of sowing and at various stages of growth indicated that these factors may have influenced the yield potential at two different dates of sowing. 相似文献
2.
The ultrastructure of sarcocysts of macro- and microscopic species of Sarcocystis was compared from naturally infected water buffalo from India. Grossly visible sarcocysts had walls consisting of cauliflower-like villar protrusions, typical of S. fusiformis. The sarcocyst wall of the microscopic species of Sarcocystis was 6.4 microns thick and consisted of tightly packed conical villar protrusions that were 9.6 microns long and 3.7 microns wide at the base. At approximately 3 microns above the base, the distal two-thirds of the villar protrusion became conical shaped and was bent laterally at an angle of 45 degrees to the sarcocyst surface. The granular layer beneath the villar protrusions was 0.9 microns thick. In S. levinei the granular layer was 1.9 microns thick, the villar protrusions were narrow and it had a highly undulating primary cyst wall. Whether the microscopic S. levinei-like sarcocysts of Indian and Malaysian water buffalo are distinct species of Sarcocystis will require further investigation. 相似文献
3.
In ruminants, the ruminal epithelium not only has the function of absorbing nutrients but also is an important tissue to prevent harmful substances in the rumen from entering the blood circulation. Thus, the normal function of ruminal epithelium is critical for ruminants. However, subacute ruminal acidosis induced by high-concentrate diets often damages the barrier function of ruminal epithelium in ruminants. Recently, many studies have shown that dietary supplementation with thiamine is an effective method to alleviate subacute ruminal acidosis. In order to provide theoretical reference for the in-depth study of subacute ruminal acidosis and the application of thiamine in the future, this review introduces the effects of subacute ruminal acidosis on morphological structure, inflammatory response, and tight junction of ruminal epithelium. In addition, this paper summarizes the role of thiamine in maintaining ruminal epithelial function of ruminants during subacute ruminal acidosis challenge. 相似文献
4.
The aim of present experiment was to evaluate the plasma concentrations of estrone sulfate (E(1)S) and progesterone (P(4)) during late gestation in recipient cows transferred embryos produced by nuclear transfer (NT) and in vitro fertilization (IVF). Blood samples were collected from recipients transferred embryos produced by NT (n=9) and IVF (n=13) at 160, 220, 240, 260 and 270 d of gestation and then at 5 d intervals until parturition. Plasma samples were analyzed for E(1)S and P(4) by ELISA. One NT and three IVF cows aborted between days 220 and 260 of gestation. Two NT and one IVF cow had prolonged gestation (over 290 d). One IVF cow had an overweight fetus (50 kg) after abortion (257 d). The patterns of changes in the concentrations of E(1)S during late gestation in the NT and IVF cows were almost identical. The NT and IVF cows that aborted had prolonged gestation and much higher E(1)S concentrations than the average. One NT cow aborted after 220 d of gestation and had a sudden high increase in its E(1)S concentration from 160 d to 220 d of gestation. The NT and IVF cows that had prolonged gestation also had significantly higher (P<0.05) P(4) concentrations than the average. These results raise the possibility that the E(1)S and P(4) profiles can be used to monitor some late gestational problems, such as higher birth weight, abortion and prolonged gestation. 相似文献
5.
长白山林区主要可燃物类型地表可燃物载量分析 总被引:5,自引:0,他引:5
对长白山林区主要可燃物类型地表可燃物载量进行了对比分析和聚类分析。通过可燃物类型载量的对比分析,得出易燃的可燃物类型是云冷杉林(鱼鳞云杉103a)、落叶松林(115a)和云冷杉林(鱼鳞云杉80a),最不易燃的是岳桦林(142a)、白桦林(87a)和岳桦林(115a);释放能量最大的可燃物类型是落叶松林(115a),释放能量最小的可燃物类型是白桦林(87a)。通过各可燃物类型的1h时滞可燃物载量和地表总可燃物载量的聚类分析,可把13个可燃物类型化为6类。 相似文献
6.
A 3 × 3 factorial experiment was conducted on Labeo rohita fingerlings to evaluate the effect of dietary oxidized oil and vitamin E. Nine experimental diets were made, based on three degrees of oil oxidation (fresh oil, low oil oxidation and high oil oxidation), and each level of oxidation was further supplemented with three levels of vitamin E (0, 100 and 1,000 mg/kg). Weight gain% and specific growth rate (SGR) of fish fed fresh fish oil and low oil oxidation level were significantly higher than highly oxidized oil. Moreover, vitamin E supplemented fish also showed better growth performance. Oil oxidation caused a significant reduction in the concentrations of α‐tocopherol and increase in TBARS level and antioxidant enzyme activities in fish liver and muscles. However, increasing the dietary vitamin E abrogated these effects. Dietary vitamin E supplementation improved the fatty acid, more specifically polyunsaturated fatty acids profile of oxidized oil fed fish. In conclusion, dietary oxidized fish oil increased the oxidative stress condition of fish but supplementation of high dose of vitamin E prevented lipid oxidation, improved growth performance and fatty acid profile of L. rohita. 相似文献
7.
Md. Shah Alam Sarker Shuichi Satoh Keisuke Kamata Yutaka Haga Yoshihiro Yamamoto 《Aquaculture Research》2012,43(4):538-545
A feeding experiment was conducted to investigate the effect of organic acids and/or lipid supplementation on growth, utilization and environmental loading of nitrogen (N) and phosphorus (P) in juvenile yellowtail fed fishmeal (FM) and plant protein (PP) diets. Six diets as FM (FM‐based), FM+P (FM with inorganic P), FM+L (FM with lipid), PP+CA (PP with citric acid), PP+L+CA (PP with lipid and citric acid) and PP+L+FA (PP with formic acid) were formulated. Yellowtails were fed each of the diets in duplicate groups; once a day, 6 days a week to near satiation at water temperature 19.0–25.0 °C for 16 weeks. Fishmeal with inorganic P gave the best growth while PP+L+FA the lowest. However, growth increased in PP+CA and PP+L+CA. Addition of lipid significantly increased N and P retention resulting in significant reduction in N and P excretion. Citric acid and FA supplementation to PP diets also increased retention of P; hence, its excretion was lowered. Thus, CA, FA and lipid in juvenile yellowtail diets can help to partially replace FM with PP sources and reduce inorganic P use to minimize environmental loading from aquafeeds. 相似文献
8.
In the low-input rice–wheat production systems of Nepal, the N nutrition of both crops is largely based on the supply from soil pools. Declining yield trends call for management interventions aiming at the avoidance of native soil N losses. A field study was conducted at two sites in the lowland and the upper mid-hills of Nepal with contrasting temperature regimes and durations of the dry-to-wet season transition period between the harvest of wheat and the transplanting of lowland rice. Technical options included the return of the straw of the preceding wheat crop, the cultivation of short-cycled crops during the transition season, and combinations of both. Dynamics of soil Nmin, nitrate leaching, nitrous oxide emissions, and crop N uptake were studied throughout the year between 2004 and 2005 and partial N balances of the cropping systems were established. In the traditional system (bare fallow between wheat and rice) a large accumulation of soil nitrate N and its subsequent disappearance upon soil saturation occurred during the transition season. This nitrate loss was associated with nitrate leaching (6.3 and 12.8 kg ha−1 at the low and high altitude sites, respectively) and peaks of nitrous oxide emissions (120 and 480 mg m−2 h−1 at the low and high altitude sites, respectively). Incorporation of wheat straw at 3 Mg ha−1 and/or cultivation of a nitrate catch crop during the transition season significantly reduced the build up of soil nitrate and subsequent N losses at the low altitude site. At the high altitude site, cumulative grain yields increased from 2.35 Mg ha−1 with bare fallow during the transition season to 3.44 Mg ha−1 when wheat straw was incorporated. At the low altitude site, the cumulative yield significantly increased from 2.85 Mg ha−1 (bare fallow) to between 3.63 and 6.63 Mg ha−1, depending on the transition season option applied. Irrespective of the site and the land use option applied during the transition season, systems N balances remained largely negative, ranging from −37 to −84 kg N ha−1. We conclude that despite reduced N losses and increased grain yields the proposed options need to be complemented with additional N inputs to sustain long-term productivity. 相似文献
9.
The inhibitory effect of mimosine on polyphenoloxidase (PPO) from the cephalothorax of Pacific white shrimp (Litopenaeus vannamei) was studied. Mimosine showed inhibitory activity toward PPO from white shrimp with an apparent molecular weight of 210 kDa as evidenced by the decrease in the activity staining band, as compared to the control. An inhibition kinetic study revealed that mimosine exhibited the mixed type reversible inhibition on PPO from white shrimp with a Ki value of 3.7 mM. Mimosine showed copper (Cu2+) reduction and chelating capacity in a dose dependent manner. Mimosine could react with the intermediate browning product, thereby rendering lower red-brown color formation. Therefore, mimosine could inhibit PPO by different modes of inhibition and could be used to prevent melanosis formation in Pacific white shrimp. 相似文献
10.