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Anthelmintic resistance in Australian sheep nematode populations   总被引:2,自引:0,他引:2  
SUMMARY The resistance status of gastro–intestinal nematodes to anthelmintics was evaluated on 881 sheep farms throughout Australia during 1991–92. Resistance was shown to be widespread. Overall, 85% of farms had sheep infected with nematodes resistant to benzimidazole, 65% to levamisole and 34% to combination (benzimidazole + levamisole) products. Resistance to ivermectin was not detcted. On only 9% of farms did all anthelmintic groups reduce egg counts by greater than or equal to 95%. The culture of faeces from untreated sheep showed Telodorsagia circumcincta, Trichostrongylus spp, Chabertia ovina and Haemonchus contortus to be the principal species. The nature and prevalence of resistance was not significantly correlated with stocking rate. However, resistance to combination products was almost twice as prevalent on farms in areas with an average annual rainfall of greater than 500 mm.  相似文献   
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The coastal shelf of the Gulf of Oman experiences periodic upwelling events during the summer months that are driven by the southwest monsoon. It is unclear what role these events play in the spatial and temporal distribution of the region’s fish assemblage. We carried out trials on two different video techniques to characterize the habitat and fish assemblage along the continental shelf margin near Muscat, Oman. Exploratory surveys with a drift stereo‐video revealed three main habitat types: Sand, Reef and Megabenthos. Three areas were chosen for additional sampling using stereo‐BRUVS (‘baited’ remote underwater‐video systems). On two separate occasions (November 2005 and March 2006) replicate stereo‐BRUVS were deployed in each area stratified by the main habitat types. For each teleost and elasmobranch species encountered on the video, an estimate of total body length and the relative abundance (MaxNi) was made. The stereo‐BRUVS recorded a wide range of demersal and pelagic teleosts including species of conservation interest such as sharks, rays and groupers. The drift stereo‐video recorded significantly fewer species than the stereo‐BRUVS (N = 15 versus N = 43). Species diversity from the stereo‐BRUVS increased by 96% in March 2006 (N = 41) compared to November 2005 (N = 23), a pattern consistent at all three areas. The structure of the overall fish assemblage (using canonical analysis of principal coordinates analysis) was highly variable both in time and space. There was ample evidence of strong habitat associations, particularly with depth and seasonal shifts in abundance and diversity. We argue the upward migration of oxygen‐depleted water into the shallow depths during the late monsoon displaces the demersal fish community along this coast.  相似文献   
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鹿蹄草等中草药对油桃采后褐腐病抑制效果研究   总被引:5,自引:2,他引:5  
在离体和活体条件下,测定鹿蹄草、厚朴等中草药单剂及鹿蹄草为主的各中草药复配组合对油桃采后褐腐病菌的抑制效果。结果表明:11号(鹿蹄草+厚朴+大黄),14号(鹿蹄草+高良姜+虎杖)复配组合在离体试验中抑菌效果最好,10 mg/mL浓度的抑制率分别达到89.77%,85.50%;两种组合的最小抑菌浓度(MIC)分别是1.25,2.5 mg/mL;最小杀菌浓度(MBC)分别是2.5,5.0 mg/mL。活体抑菌测定结果表明,11号和14号复配组合对油桃褐腐病菌有不同程度延缓侵染和抑制作用,但不能完全防治;0.05 mg/mL扑海因与11号组合20 mg/mL,0.10 mg/mL扑海因与11号组合10 mg/mL均能完全抑制褐腐病菌在油桃果实上的发生和蔓延。  相似文献   
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The study postulated that differential nutritional management during the early lactation period would be reflected in endometrial expression of genes related to embryo growth at the end of the voluntary waiting period. Thus, the effect of the combined use of total mixed ration (TMR) and grazing under different herbage allowances during the first 75 days post‐partum (DPP) on endometrial gene expression was evaluated in primiparous dairy cows. Cows were blocked by body weight, age and body condition score and randomly assigned to three grazing treatments: high (HA, 30 kg DM per cow per day), medium (MA, 15 kg DM per cow per day) and low (LA, 7.5 kg DM per cow per day) herbage allowance (mixed pasture, 2,600 kg DM per ha) plus 8 kg DM of supplement or TMR (55% forage, 45% concentrate) fed ad libitum (TMR) from calving to 75 DPP. At 57 DPP, cows were synchronized for oestrus (day 0, 68 DPP) and at day 7, endometrial biopsies were obtained. The nutritional treatment did not affect insulin, IGF‐1 and leptin concentrations on days 0, 4 or 7. Expression of IGF1, IGFBP3, IGFBP4, ADIPOR1 and ADIPOR2 mRNA was significantly affected by the nutritional treatment. Endometrial IGF1 and IGFBP4 mRNA were twofold greater in TMR and HA than MA and LA cows. Expression of IGFBP3 and ADIPOR1 mRNAs was greater in TMR and HA than MA cows, but did not differ from LA cows. All groups had greater expression of ADIPOR2 mRNA than MA cows. This study provided solid evidence of the importance of nutritional management during early lactation on uterine environment at the end of the voluntary waiting period. The greater expression of genes related to embryo growth and uterine function (IGF system, progesterone and adiponectin receptors) in cows fed diets maximizing energy intake suggests a favourable environment for embryonic growth, which may explain the improved reproductive performance of cows in good energy balance.  相似文献   
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Summary The paper deals with studies on the dynamics of Carbaryl residue loss on apples, plums and peaches.The initial toxicant deposit ranges between 8 and 13 ppm on peaches, 2, 3 and 3, 4 ppm on apples and up to 1.5 ppm on plums. According to the dynamics of Carbaryl residue loss on fruit results a rest period of 2 days for plums, 7 days for apples and 21 days for peaches, on admitting a 2 ppm tolerance.
Zusammenfassung Unter Berücksichtigung der Witterungsbedingungen wurde die Geschwindigkeit des Abbaus von Carbaryl-Rückständen bei Äpfeln, Pflaumen und Pfirsichen untersucht. Die anfängliche Höhe der Rückstände betrug bei Pfirsichen zwischen 8 und 13 ppm, bei Äpfeln 2,3 und 3,4 ppm und bei Pflaumen bis zu 1,5 ppm. Wird eine Toleranz von 2 ppm zugrundegelegt, ergibt sich entsprechend der Abbau-Geschwindigkeit von Carbaryl bei Früchten eine Wartezeit von 2 Tagen bei Pflaumen, 7 Tagen bei Äpfeln und 21 Tagen bei Pfirsichen.

Resume On présente de données sur la dynamique de la dégradation des résidus de Carbaryl sur pommes, prunes et pêches. Le résidu initial atteint 8–13 ppm chez les pêches, 2,3–3,4 ppm chez les pommes et 1,5 ppm chez les prunes.De cette dynamique de la dégradation des résidue sur fruits il résulte que pour les prunes l'intervalle de pause de deur jours, pour les pommes de 7 jours et pour les pêches de 25 jours dans les conditions climatiques de Roumanie.


Presented at the Congress of Chemistry in Agriculture, Bratislava, Sept. 1969.  相似文献   
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本研究从哈尔滨郊区某鸡场肿头综合征( S H S)鸡分离出 3 株血清型为 O78 的埃希氏大肠杆菌( E.coli),从鞍山 S H S病料分离出 1 株血清型为 O8 的 E.coli。并证实这 4 株 E.coli 能够对 Vero 细胞产生毒性作用,与产 Vero 毒素的 E.coli一致。对哈尔滨市郊 S H S病鸡做病理组织学观察,主要变化为头部皮下组织,头盖骨气室及鼻粘膜下纤维素性化脓性炎症,水肿和大肠杆菌性肉芽肿,心、肝、肾等器官炎症变化并有大量异嗜性粒细胞和细菌团块。  相似文献   
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