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Sara Sánchez-Moreno Nicole L. Nicola Howard Ferris Frank G. Zalom 《Applied soil ecology》2009,41(1):107-117
Biological indicators based on abundances of soil organisms are powerful tools for inferring functional and diversity changes in soils affected by agricultural perturbations. Field plots, combining organic and conventional practices with no tillage, conservation tillage and standard tillage maintained different nematode assemblages and soil food webs. Soil food web indices based on nematode assemblages were reliable predictors of the trophic composition of functional characteristics of soil mite assemblages. Bacterial-feeding and predatory nematodes, together with predatory mites, were abundant in the organic-no till treatments and were associated with high values of the Enrichment and the Structure Index based on nematode assemblages. Conventional-Standard tillage treatments had high abundances of fungal- and plant-feeding nematodes and algivorous mites, associated with high values of the Basal and Channel Index. This study validates the hypothesis that nematode-based soil food web indices are useful indicators of other soil organisms such as mites, with similar functional roles and environmental sensitivities. 相似文献
23.
A. HüTtermann Marie-Therese Oelbe E. Fritz G. Schlechte A. Bytom A. D. Jungk Y. Okon E. Fallik Rivka Hadas S. Sarig E. Yahalom Sara Tal A. Hartmann B. Kishinevsky Debora Gurfel Rina Lobel Y. Kapulnik D. A. Phillips Y. Hadar Y. Chen E. Jurkevitch J. Katan A. Gamliel H. Ziegler I. Chet A. Ordentlich Hadar Kless A. Oppenheim Avia Zilberstein D. Holland J. Berman A. Zamir R. Kaufman N. Bawnik C. Koncz J. Schell 《Phytoparasitica》1987,15(2):141-147
24.
Sara E Childs-Sanford Rachel M Peters James K Morrisey Ana Alcaraz 《Journal of zoo and wildlife medicine》2005,36(2):308-312
An adult, female binturong (Arctictis binturong) was examined due to lethargy, inappetence, and an abdominal mass. Diagnostic investigations, including radiographs, abdominal ultrasound, clinical laboratory findings, and a fine-needle aspirate of the mass, were suggestive of a sarcoma with metastasis. Necropsy and histopathologic findings confirmed a widely disseminated sarcomatoid variant of a renal cell carcinoma, likely originating in the left kidney, with metastasis to the right kidney, spleen, pancreas, liver, mesenteric lymph nodes, and lungs. This is the first report of this neoplasm in a binturong and only the second report in the veterinary literature. Sarcomatoid renal cell carcinoma is a rare histologic variant of renal cell carcinoma that is aggressive, commonly metastatic, and associated with a very poor prognosis in humans. Accurate antemortem diagnosis of this tumor may be complicated by its biphasic morphology, which may resemble carcinoma or sarcoma (or both), often necessitating the use of immunohistochemical techniques. 相似文献
25.
Musser RE Goodband RD Tokach MD Owen KQ Nelssen JL Blum SA Campbell RG Smits R Dritz SS Civis CA 《Journal of animal science》1999,77(12):3296-3303
Sows of differing parities and genetics were used at different locations to determine the effects of feeding added L-carnitine during lactation on sow and litter performance. In Exp. 1, sows (n = 50 PIC C15) were fed a lactation diet (1.0% total lysine, .9% Ca, and .8% P) with or without 50 ppm of added L-carnitine from d 108 of gestation until weaning (d 21). No differences in litter weaning weight, survivability, sow ADFI, or sow weight and last rib fat depth change were observed. Number of pigs born alive in the subsequent farrowing were not different (P>.10). In Exp. 2, parity-three and -four sows (n = 115 Large White cross) were used to determine the effect of feeding 0, 50, 100, or 200 ppm of added L-carnitine during lactation (diet containing .9% total lysine, 1.0% Ca, and .8% P) on sow and litter performance. No improvements in the number of pigs or litter weights at weaning were observed (P>.10). Sows fed added L-carnitine had increased weight loss (linear; P<.04), but no differences (P>.10) were observed in last rib fat depth change or subsequent reproductive performance. In Exp. 3, first-parity sows (n = 107 PIC C15) were fed a diet with or without 50 ppm of added L-carnitine during lactation (diet containing 1.0% total lysine). Sows fed added L-carnitine tended (P<.10) to have fewer stillborn and mummified pigs than controls (.42 vs .81 pigs). No differences were observed for litter weaning weight, survivability, or subsequent farrowing performance. Feeding 50 to 200 ppm of added L-carnitine during lactation had little effect on sow and litter performance. 相似文献
26.
E. Owen 《Agricultural Systems》1983,11(1):66
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Dietary ZR-512 and ZR-619 at concentrations of 10 — 1000 ppm induced prolongation of the larval feeding period up to tenfold, increasing larval weight up to double that of untreated larvae. A comparison study of four juvenoids, using 200 ppm of ZR-512, ZR-515, ZR-619 or ZR-777, showed that ZR-515 elicits the highest larval weight (6.2 mg) and ZR-777 the lowest (3.6 mg). In all cases a pronounced enhancement of larval weight — of 50 — 250% relative to untreated larvae (2.4 mg) — was obtained.Tr. castaneum larvae reared up to their 3rd instars on a diet containing 100 ppm of ZR-512, ZR-515, ZR-619 or ZR-777 and then transferred to a juvenile hormone-free diet, were not affected. The period between 4th instar larva and pupation should therefore be considered as critical for juvenile hormone effect. The induced prolongation of the larval stage after juvenile hormone treatment was followed by a pronounced enhancement of cuticle phenoloxidase activity, indicating an alteration of the larval biochemical processes. Although juvenile hormone treatment inhibitsTr. castaneum pupation and emergence, it markedly prolongs larval feeding stage and weight and thus accelerates damage. 相似文献
29.
Enigmatic resistance of sheep (Ovis aries) to infection by virulent Francisella tularensis. 下载免费PDF全文
Tularemia in range sheep is an occasional cause of severe economic loss from mortality and unthriftiness as well as a hazard to persons in contact with the animals. Epizootics are unpredictable and explosive, therefore, prophylaxis is more practical than therapy. Live vaccine of proven value in man and in beavers was inoculated into mature ewes and elicited antibodies without harm to the sheep. However, challenge of immunity was not possible because virulent Francisella tularensis in large doses did not cause significant mortality in healthy, well managed, unimmunized sheep. Evidence suggests that a complex of stresses such as inclement weather, lambing and concomitant ectoparasitism render sheep more susceptible to tularemia. 相似文献
30.
Rehbein S Holste JE Doucet MY Fenger C Paul AJ Reinemeyer CR Smith LL Yoon S Marley SE 《Veterinary therapeutics : research in applied veterinary medicine》2003,4(3):220-227
The efficacy of an oral formulation of ivermectin plus praziquantel in the reduction of nematode and cestode egg counts in horses was assessed in 273 horses under field conditions at 15 sites in North America (n = 6) and Europe (n = 9). Horses were confirmed by fecal examination to have natural infections of strongyles (100%) and tapeworms (76%). Replicates of four horses were formed at each site, and in each replicate three animals received ivermectin (0.2 mg/kg body weight) plus praziquantel (1 mg/kg body weight) oral paste and one animal remained untreated or received vehicle paste. Fecal samples were collected for fecal nematode and cestode egg counting before and 7, 8, 9, 14, 15, and 16 days after treatment. Horses treated with ivermectin plus praziquantel oral paste had significantly (P <.01) lower posttreatment strongylid and cestode egg counts (reductions of 98% or more) than controls. Combined site analyses revealed that 95% or 96% of the horses positive for cestode eggs before treatment that were treated with ivermectin plus praziquantel were negative for cestode eggs at each posttreatment fecal examination. No adverse reactions attributable to ivermectin plus praziquantel oral paste treatments were observed. The results of the studies demonstrated that ivermectin plus praziquantel paste was highly effective in reducing egg shedding by gastrointestinal nematodes and cestodes, and no adverse reactions were observed in horses treated under field conditions. 相似文献