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Glasshouse and field trials were conducted to determine the effects of the cyst nematode, Heterodera cajani on biomass and grain yield of pigeon pea, Cajanus cajan. Shoot length, fresh and dry shoot masses, leaf area and pod yields of pigeon pea were significantly reduced by H. cajani. In glasshouse pot experiments, an initial density of 1.0 juveniles per cm3 soil caused 14 to 24% reduction in plant height, root and shoot mass and leaf area. Application of carbofuran 3G (1·5, 3·0 and 6·0 kg a.i./ha) in H. autoclaved soil in pots did not improve growth of pigeon pea; however, its application (6 kg a.i./ha) in H. cajani -infested fields reduced the nematode density ( P < 0·05) and improved plant growth and yield. The densities of eggs and juveniles of H. cajani were 72 and 48% lower in the carbofuran-treated plots than in the control plots 35 and 52 days, respectively, after sowing. No such differences were observed at 70 days after sowing. The tolerance limit for pod yield in field experiments was 2·6 eggs and juveniles of H. cajani per cm3 soil at sowing time. Grain yield was 20 to 25% higher in the carbofuran-treated plots than in the control plots. Application of carbofuran protected the roots from nematode damage during the early stages of plant growth and resulted in good plant growth and yield. 相似文献
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E Axnér C Linde Forsberg Correction added after online publication April : from CL Forsberg to C Linde Forsberg 《Reproduction in domestic animals》2007,42(3):282-291
Knowledge about normal ranges in semen quality and the association between sperm morphology and fertility in felids is limited. The aims of this retrospective study were to (1) define a normal spermiogram in cats; (2) evaluate possible effects of season, age and breed on sperm morphology; and (3) evaluate the relationship between sperm morphology and fertility. Semen samples collected by electroejaculation from 52 cats were evaluated for sperm morphology. The cats constituted two groups: a general population of cats (n = 48) and cats examined because of poor breeding records (n = 4). The general population was divided into household (n = 20), pedigree (n = 19) and colony cats (n = 9) and into three age classes, <12 months, 12-59 months and >or=60 months. The median percentage of normal spermatozoa in the general population was 44.0% (range 1.0-91.0%). Criteria were tentatively set for what was considered a normal spermiogram. The mean percentage of normal spermatozoa was higher during February to July than during August to January (p < 0.05). Pedigree cats had a lower mean percentage of normal spermatozoa than did household cats (p < 0.05). Age had no effect on the percentage of normal spermatozoa but was positively correlated with the percentage of proximal droplets. Of the cats with <40% normal spermatozoa (n = 19), all those with known breeding records (n = 11) had produced litters. The four cats examined because of poor breeding results had higher percentages of different sperm abnormalities than tentatively stipulated for the normal spermiogram. In two of these cats both sperm morphology and fertility changed over time. 相似文献
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RT NORRIS CL McDONALD RB RICHARDS MW HYDER SP GITTINS GJ NORMAN 《Australian veterinary journal》1990,67(7):244-247
In the first of 2 experiments, a simulated voyage was conducted to examine the effects of various treatments on bodyweight change and feeding frequency of inappetant sheep at the end of lot-feeding (non-feeders). The treatments, applied during simulated shipping, were: normal quantities of feed and length of troughs; extra trough length; extra feed. Adult Merino wethers (n = 108) were used in each treatment. A voyage to the Middle East was then conducted to establish whether shipboard mortality could be reduced by separating non-feeders (n = 305) from feeders (n = 5,620) late in the feedlot hase and housing the groups separately aboard ship. A control group of non-feeders (n = 215) mixed with feeders (n = 5,732) was used for comparison. Bars (marker bars), containing a coloured dye, were attached to feed troughs to mark sheep that fed. Most non-feeders (82%) began eating when placed in shipping pens in both studies. However, there was no significant difference in percentage of sheep that fed between non-feeders given extra trough length or extra feed compared with non-feeders given standard management at any stage of simulated shipping. There was no significant difference in mean bodyweights between treatment groups on days 1, 8 and 15 of simulated shipping. Differences in bodyweight on d 22 were probably associated with different levels of gut fill. Death rates were not significantly different in separated and control groups (1.1%, 0.9%, P = 0.6) in the voyage of 14 d to the Middle East.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Effect of Oil Overlay on Inhibition Potential of Roscovitine in Sheep Cumulus‐Oocyte Complexes 下载免费PDF全文
LF Crocomo WC Marques Filho CMV Ulian NS Branchini DT Silva CL Ackermann FC Landim‐Alvarenga SD Bicudo 《Reproduction in domestic animals》2015,50(3):410-416
Inhibitors of cyclin‐dependent kinases, as roscovitine, have been used to prevent the spontaneous resumption of meiosis in vitro and to improve the oocyte developmental competence. In this study, the interference of oil overlay on the reversible arrest capacity of roscovitine in sheep oocytes as well as its effects on cumulus expansion was evaluated. For this, cumulus‐oocyte complexes (COCs) were cultured for 20 h in TCM 199 with 10% foetal bovine serum (Control) containing 75 μm roscovitine (Rosco). Subsequently, they were in vitro matured (IVM) for further 18 h in inhibitor‐free medium with LH and FSH. The culture was performed in Petri dishes under mineral oil (+) or in 96 well plates without oil overlay (?) at 38.5°C and 5% CO2. At 20 and 38 h, the cumulus expansion and nuclear maturation were evaluated under stereomicroscope and by Hoechst 33342 staining, respectively. No group presented cumulus expansion at 20 h. After additional culture with gonadotrophins, a significant rate of COCs from both Control groups (+/?) exhibited total expansion while in both Rosco groups (+/?) the partial expansion prevailed. Among the oocytes treated with roscovitine, 65.2% were kept at GV in the absence of oil overlay while 40.6% of them reached MII under oil cover (p < 0.05). This meiotic arrest was reversible, and proper meiosis progression also occurred in the Control groups (+/?). So, the culture system without oil overlay improved the meiotic inhibition promoted by roscovitine without affecting the cumulus expansion rate or the subsequent meiosis progression. 相似文献
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Searching the world wide Web 总被引:8,自引:0,他引:8
The coverage and recency of the major World Wide Web search engines was analyzed, yielding some surprising results. The coverage of any one engine is significantly limited: No single engine indexes more than about one-third of the "indexable Web," the coverage of the six engines investigated varies by an order of magnitude, and combining the results of the six engines yields about 3.5 times as many documents on average as compared with the results from only one engine. Analysis of the overlap between pairs of engines gives an estimated lower bound on the size of the indexable Web of 320 million pages. 相似文献