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61.
稻瘟病综合防治技术应用   总被引:3,自引:0,他引:3  
 综防技术应用表明,遵义地区稻瘟病逐渐得到控制,叶瘟发生由1993年的7.36×104hm2,下降到1996年的3.51×104hm2,穗瘟发生也由当年的9.25×104hm2下降到1.31×104hm2,综防治理区稻谷平均667m2产量达577.82kg,比非综防区平均667m2增产81.1kg,共挽回因病虫危害造成的产量损失约7.64×107t,折款1069.8856万元,产出比1:3.5,效益显著.  相似文献   
62.
Accelerator mass spectrometer dating of an assemblage of fibrous and leather footwear from Arnold Research Cave in central Missouri documents a long sequence of shoe construction by prehistoric Midwestern peoples, beginning perhaps as early as 8300 calendar years before the present (cal years B.P.). An earlier fibrous sandal form dates from 8325 to 7675 cal years B.P., and later fibrous or leather slip-ons span the period from 5575 to 1070 cal years B.P. The assemblage adds to a growing picture of the highly varied nature of prehistoric footwear production in the United States throughout the Holocene.  相似文献   
63.
去除种皮与不去种皮的鸢尾种子之间的萌发效果具有显著差异,表现为开始萌发的时间,前者较后者明显提早;萌发百分率,前者显著高于后者,卡平方(χ2)独立性测验达极显著水平。可见,鸢尾种皮对鸢尾种子的萌发具有强烈的抑制作用。实验表明,鸢尾种子的萌发受种皮内源抑制物、种皮透性和种皮机械阻力的共同影响  相似文献   
64.
水库水质之时间数列分析研究   总被引:1,自引:0,他引:1  
本研究将以德基水库中总磷资料计算 TSI(Trophic Status Index)优养指数,并利用相乘性分解方法(multiplicative decomposition method)进行德基水库水质优养化时间数列分析研究,用以了解德基水库水质之优养化变化情形。研究显示,德基水库季节变化(S)之水质优养化变动情形每年有一高峰期,从 4~10月,总长度达 7个月之久。此外,德基水库优养指数长期趋势(T)乃显示随时间(t)呈缓慢成长状态,其间的关系可表示为 T =51.4231+ 0.0605t,其中 t=1,2,3……,161。至于在循环变动(C)的研究中则发现,循环变动周期自早期的 2~3年,逐渐缩减至 1年左右。由此可知,德基水库水质优养化的情形有日益严重的趋势。  相似文献   
65.
The effect of prepubertal feed level on growth and reproductive development of gilts was investigated. At 13 wk. of age, white crossbred gilts were penned individually and assigned to the following treatments: Ad lib, ad libitum intake from 13 to 25 wk. of age (n = 64); Control, ad libitum intake from 13 wk. of age until 100 kg BW and then 90% of ad libitum intake until 25 wk. of age (n = 65); and Restricted, 74% of ad libitum intake from 13 wk. to 25 wk. of age (n = 64). Feed was formulated to primarily restrict energy intake. The study was replicated in two seasons. At 25 wk. of age, gilts were moved to group pens, approximately 16 gilts/pen, allowed ad libitum access to feed, and estrus detection was initiated. Gilts were mated at first estrus and those recycling were remated. After mating, gilts were moved to gestation stalls and fed 1.5x maintenance. At 30 d of gestation, reproductive tracts were harvested, and numbers of corpora lutea (CL) and live embryos were recorded. From 13 to 25 wk. of age, feed consumption was 258 for Ad lib, 251 for Control, and 189 kg/gilt for Restricted, and, from 13 wk. of age until 30 d of gestation, total feed consumption was 367 for Ad lib, 356 for Control, and 299 kg/gilt for Restricted gilts. Age at puberty (196 d) and pregnancy (200 d) was not affected (P>.18) by treatment. However, the rate at which gilts attained puberty (e.g., percentage pubertal at 28 d) was greatest in Ad lib (75) and least in Control (61) gilts. Number of CL and live embryos at 30 d of gestation/gilt assigned to the study was unaffected (P>.21) by treatment. Quantity of feed consumed from 13 wk. of age to 30 d of gestation per live embryo in gilts assigned to the study was 40.0 for Ad lib, 39.8 for Control, and 30.6 kg/gilt for Restricted gilts. These results indicate that moderate feed restriction of gilts during prepubertal development may increase efficiency of swine production without negative impact on reproductive performance through 30 d of gestation.  相似文献   
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68.
Effectiveness of a non-surgical alternative to the Mules operation in sheep   总被引:1,自引:1,他引:0  
Objective To measure changes to the perineal bare area, local tissue reaction and healing responses of young sheep, following intradermal administration of cetrimide and polyvinylpyrrolidone (PVP), with and without ethanol, to the breech and tail. Method A needle‐less injector was used to deposit formulations containing 40 g/L cetrimide and 30 g/L PVP (group 2) or 20 g/L cetrimide, 30 g/L PVP and 15 g/L ethanol (group 3), within the dermis of the tail and the region surrounding the perineal bare breech area of groups (N = 8) of Merino weaner sheep. The dimensions of the perineal bare area (length, width and diagonal distances left and right) and tail width were recorded before and at intervals after treatment for 60 days. Observations of swelling and bruising and scab formation at the treatment sites were recorded for up to 35 days after treatment. Rectal temperatures were monitored for up to 35 days after treatment and bodyweight for up to 60 days after treatment. An untreated control group (group 1) was included. Results Comparison of day ‐3 and day 35 measurement data showed that both treated groups had significantly (P < 0.05) wider breech bare areas compared to the untreated controls and that group 2 sheep had significantly (P < 0.05) longer breech bare areas compared to group 3 sheep or to the untreated controls, which were not significantly different. At this time scabs were still firmly in place on many treated sheep. At day 35 there was no increase in tail bare area caused by either treatment. By day 60 there was no significant difference between the treated and control groups in either the breech or tail regions indicating that the changes present at day 35, were not permanent. Mean weight gain in the groups throughout the 60‐day interval was unaffected by treatment. Intradermal treatment was associated with a significant elevation in body temperature. This effect lasted for 3 days and was associated with signs of discomfort and depressed appearance in at least some of the treated sheep. Bruising was mild to severe in all treated sheep within two days of treatment but was not evident in any sheep by day 21. Mild to moderate swelling was also associated with treatment but was not uniform across sheep in the groups. The tail of one sheep was severely swollen for several days. Swelling remained obvious in most treated sheep until day 14 but was not present at day 21. Conclusion Under the conditions of this study intradermal injection of cetrimide had no permanent effect on bare area measurements on the breech or the amount of wool‐bearing skin on the tail. It also caused signs of discomfort and pain that raise welfare concerns.  相似文献   
69.
Objective   To determine a reference range for serum cobalamin concentration in healthy cats in Australia using a chemiluminescent enzyme immunoassay and to prospectively investigate the prevalence of hypocobalaminaemia in cats with non-alimentary tract disease.
Design   Prospective study measuring serum cobalamin concentrations in clinically healthy cats and cats with non-alimentary tract illness.
Procedure   Blood was collected from 50 clinically healthy cats that were owned by staff and associates of Veterinary Specialist Services or were owned animals presented to Creek Road Cat Clinic for routine vaccination. Blood was collected from 47 cats with non-alimentary tract illness presented at either clinic. Serum cobalamin concentration was determined for each group using a chemiluminescent enzyme immunoassay.
Results   A reference range for Australian cats calculated using the central 95th percentile in the 50 clinically healthy cats was 345 to 3668 pg/mL. Median serum cobalamin concentration in 47 cats with non-alimentary tract illness (1186 pg/mL; range 117–3480) was not significantly different to the median serum cobalamin of the 50 healthy cats (1213 pg/mL, range 311–3688). Using the calculated reference range one sick cat with non-alimentary tract illness had a markedly low serum cobalamin concentration.
Conclusion   Although hypocobalaminaemia is uncommon in sick cats with non-alimentary tract illness in Australia, its occurrence in this study warrants further investigation.  相似文献   
70.
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