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961.
Attack of tea plant (Camellia sinensis (L.) O. Kuntze) leaves by the tea mosquito bugHelopeltis theivora (Hemiptera: Miridae) was positively correlated to temperature and rainfall, and partially to humidity, as determined in 12
varieties during the period 2000–2002. The insect attack was severe during the months of May–September, which had high temperature
and rainfall, and led to severe loss of biomass due to curling and drying up of the leaves. The biochemical response of these
12 varieties of tea to attack by the insect was determined with special reference to oxidative enzymes and flavonoid flavor
components. Insect attack led to an increase in the activities of the oxidative enzymes peroxidase, ascorbate peroxidase and
polyphenol oxidase. Activities of phenyl alanine ammonia lyase generally decreased as a result of insect attack, which was
significant in the United Planters Association of South India (UPASI) varieties. A significant decrease in polyphenols was
also obtained in UPASI varieties. HPLC analysis of catechins revealed a decrease in some of the catechins in the infected
leaves. Analysis of theaflavins from infusion of healthy andHelopeltis-infested tea leaves revealed no changes.
http://www.phytoparasitica.org posting Dec. 19, 2004. 相似文献
962.
In vitro effects of temperature and wet periods on infection of oilseed rape by Alternaria brassicae
The influence of temperature and duration of wet periods on infection of oilseed rape by Alternaria brassicae was studied on detached leaves and pods, leaf disks and intact seedlings. Infections increased with age of leaf and the interaction between temperature and leaf age was highly significant. On older leaves infection was optimal at 25°C. There were many infections also at 15, 20 and 29 C but relatively few infections at 10°C. On pods most infections were observed at 20 C, the highest temperature studied. Infection at each temperature increased progressively with duration of surface wetness. The minimum wet periods for infection of leaves were 3 h at 20–25°C, 4 h at 15°C, 6–9 h at 10 C and 12–24 h at 5 C and for infection of pods, between 6 h and 9 h at 10°C and 6 h (or less) at 15°C and 20 C. On leaves, dry periods interrupting wet periods limited lesion development to that obtained with the initial wet period only; on pods some further infections developed when pods were re-wetted. Dry periods of 3 h and 6 h following the inoculation of pods reduced subsequent infection but there was no further reduction by longer periods of drying to 48 h. 相似文献
963.
964.
Braun U 《Veterinary journal (London, England : 1997)》2003,166(2):112-124
Ultrasonography is an ideal diagnostic tool for investigating gastrointestinal disorders in cattle. It is performed on standing non-sedated cattle using a 3.5 MHz linear transducer. In animals with traumatic reticuloperitonitis, inflammatory fibrinous changes, and abscesses can be imaged; however, magnets and foreign bodies are difficult to visualize because of the gas content of the reticulum. Ultrasonography can be used to assess the size, position and contents of the abomasum. Percutaneous ultrasound-guided abomasocentesis can be performed to evaluate the nature and chemical composition of its contents. In left displacement of the abomasum, the abomasum is seen between the left abdominal wall and the rumen. It contains fluid ingesta ventrally and a gas cap of varying size dorsally. Occasionally, the abomasal folds are seen in the ingesta. In cattle with right displacement of the abomasum, the liver is displaced medially from the right abdominal wall by the abomasum, which has an ultrasonographic appearance similar to that described for left displacement. Motility and diameter of the intestine are the most important criteria for ultrasonographic assessment of ileus. However, the cause of the ileus is rarely determined using ultrasonography. In cases with ileus of the small intestine, there is at least one region of dilatation of the intestine and motility is reduced or absent. In cattle with caecal dilatation, the caecum can always be imaged from the right lateral abdominal wall. The wall of the caecum closest to the transducer appears as a thick, echogenic, semi-circular line. 相似文献
965.
966.
Cardiovascular and allied actions of xylazine and atropine in the unanaesthetized goat 总被引:1,自引:0,他引:1
The cardiovascular effects of xylazine and atropine, separately and in combination, were studied in goats. Methylatropine was used to distinguish between the central and peripheral effects of atropine. Mean arterial blood pressure and heart rate were recorded, and the sedative effect and changes in respiration and salivation noted. Intravenous infusion of xylazine (2.4-80.0 micrograms/kg) decreased mean arterial blood pressure and heart rate in a dose-dependent manner. Single intravenous injections of both atropine sulphate (0.1 mg/kg) and methylatropine bromide (0.05 mg/kg) increased blood pressure and heart rate. After methylatropine, tachycardia lasted twice as long as after atropine. Following atropinization, a potentiated rise in mean arterial blood pressure was present during the infusion of xylazine (80 micrograms/kg). Xylazine-induced bradycardia was reversed by both atropine and methylatropine. The action of atropine is presumed to be primarily peripheral because of the similar effects with methylatropine. Xylazine-induced sedation was dose dependent. At the highest dose the goats were unable to stand for 30-60 min, respiration became irregular with periods of apnoea, and saliva started to drip a few minutes after infusion without increased salivation. Atropine had no visible effect on the sedation, pattern of respiration or saliva dripping effect of xylazine. 相似文献
967.
Anaplasmosis in cattle in Switzerland 总被引:1,自引:0,他引:1
968.
Abate O Zanatta R Malisano T Dotta U 《Veterinary journal (London, England : 1997)》2000,159(2):154-160
Serum protein values were determined in 26 healthy dogs using agarose gel electrophoresis (SPE), splitting the electrophoretic separation into six regions: albumin, alpha(1), alpha(2), beta(1), beta(2)and gamma globulins. High-resolution electrophoresis (HRE) was used to separate single proteins. Serum proteins from dogs (26 healthy and 20 affected by various diseases) were then characterized by electrophoretic immunofixation (IFE) and Sudan black staining on HRE film. Haemoglobin and normal canine plasma and serum were used to identify haptoglobin and fibrinogen, respectively.In the standard pattern, determined by HRE, the following proteins were identified: albumin, alpha(1)-lipoprotein (alpha(1)-region), haptoglobin and alpha(2)-macroglobulin (alpha(2)-region), beta -lipoprotein and C3 (beta(1)-region), transferrin and IgM (beta(2)-region), IgG (mostly in gamma -region and partly in beta(2)-region). The HRE pattern shown by healthy dogs could be compared with those of dogs affected by various diseases to obtain clinical information. 相似文献
969.
Prevalence of Cryptosporidium sp in equids in Louisiana 总被引:3,自引:0,他引:3
S U Coleman T R Klei D D French M R Chapman R E Corstvet 《American journal of veterinary research》1989,50(4):575-577
In 1985, 22 pony foals reared in a helminth-free environment were tested daily for oocysts of Cryptosporidium sp by use of fecal flotation. Oocysts were found in all foals. Oocysts were first observed in feces collected from foals 9 to 28 days after birth. The mean period of oocyst shedding was 10 days and ranged from 2 to 18 days in individual foals. Diarrhea was observed in 14 of 22 (64%) foals and began before the period of oocyst shedding. Fecal samples also were examined for other infective agents. Salmonella poona was isolated from 1 foal that did not have diarrhea, and coronavirus particles were observed in the feces of 2 foals with diarrhea. Cryptosporidium sp oocysts also were observed in feces of 2 of 17 Thoroughbred foals, 3 of 14 Quarter Horse foals, and 3 of 26 pony foals reared on pastures with their dams. Samples from pasture-reared foals were collected at irregular intervals. Of the 11 Cryptosporidium-positive fecal samples collected from pastured foals, 2 were from foals with diarrhea. A similar survey was conducted during the 1986 foaling season, using the same procedures. Examination of 300 samples from 58 Quarter Horse, Arabian, and pony foals did not detect oocysts. Daily examination of feces from 10 pony foals reared under helminth-free conditions for 30 days also failed to detect Cryptosporidium oocysts. 相似文献
970.
Toleration-oriented insemination was applied to 1,373 oestrous sows that had undergone bio-engineering treatment, with two insemination portions having been used for each oestrous. Five International Units of oxytocin were added immediately before insemination proper to the semen applied to 315 gilts and 377 old sows. The control group included 296 gilts and 385 old sows inseminated in parallel. Semen intake, on average, was complete between four and eight minutes with the majority of gilts and between four and seven minutes with most of the old sows, but no evidence was obtained as to any action of the oxytoxin upon intake intensity. The treated gilts were superior to the controls by 6.3 per cent in pregnancy rate and by 56 born piglets to each 100 first inseminations. Superiority, consequently, was significant. In both gilts and old sows added oxytocin prolonged insemination by more than five minutes and gave clearly better fertility results. 相似文献