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61.
In an effort to save regulatory resources, the US Environmental Protection Agency and individual states have interpreted the Clean Water Act in a manner that authorizes discharges from concentrated animal feeding operations without the review of nutrient management plans. Environmental groups have objected to the abbreviated regulatory procedures, and courts have ruled that permitting agencies must review substantive documentation of effluent limitations contained in nutrient management plans. Proposed new federal regulations prescribing the requirement of a meaningful review of appropriate documentation by the permitting agency respond to the judicial mandates. To facilitate regulatory approval, regulators might use a state certification program to achieve the obligatory meaningful review. Independent certifiers would ensure that an operation's land application of manure meets federal water quality requirements.  相似文献   
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Tritrichomonas foetus is recognized as the causative agent of venereal trichomoniasis in cattle. It is characterized by embryonic and early fetal death and post-coital pyometra, and feline trichomoniasis, manifest as chronic, large bowel diarrhea. Many of the infected cats are less than 2 years old and specific routes of transmission remain unknown. We recently demonstrated that feline isolates of T. foetus can successfully infect heifers, resulting in pathologic changes similar, but not identical to those previously reported as representative of bovine trichomoniasis. In this study, we experimentally infected six cats less than 1 year of age with a bovine (D-1) isolate of T. foetus and one cat with a feline (AUTf-1) isolate of T. foetus. Within 2 weeks, the cat infected with the feline (AUTf-1) isolate was culture positive for trichomonads in weekly fecal samples. At the end of 5 weeks, only one cat infected with the bovine (D-1) isolate was fecal culture positive for trichomonads. At necropsy, the intestine of each cat was removed and divided into five sections (ileum, cecum, anterior, medial and posterior colon). Contents from each section were collected and cultured. The cat infected with the feline (AUTf-1) isolate was culture positive in the ileum, cecum, medial and posterior colon. Two cats infected with the bovine (D-1) isolate were culture positive in the cecum only. Additionally, each intestinal section was submitted to a pathologist for histopathological examination. The combined results indicate that there are demonstrable differences between the feline (AUTf-1) and bovine (D-1) isolates regarding their infectivity in cats.  相似文献   
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Adults of Sitona lineatus (pea leaf weevil, PLW) feed on foliage of several Fabaceae species but larvae prefer to feed on nodules of Pisum sativum L. and Vicia faba L. Indirectly, through their feeding on rhizobia, weevils can reduce soil and plant available nitrogen (N). However, initial soil N can reduce nodulation and damage by the weevil and reduce control requirements. Understanding these interactions is necessary to make integrated pest management recommendations for PLW. We conducted a greenhouse study to quantify nodulation, soil and plant N content, and nodule damage by weevil larvae in relation to soil N amendment with urea, thiamethoxam insecticide seed coating and crop stage. PLWs reduced the number of older tumescent (multilobed) nodules and thiamethoxam addition increased them regardless of other factors. Nitrogen amendment significantly increased soil available N (>99% nitrate) as expected and PLW presence was associated with significantly lower levels of soil N. PLW decreased plant N content at early flower and thiamethoxam increased it, particularly at late flower. The study illustrated the complexity of interactions that determine insect herbivory effects on plant and soil nutrition for invertebrates that feed on N-fixing root nodules. We conclude that effects of PLW on nodulation and subsequent effects on plant nitrogen are more pronounced during the early growth stages of the plant. This suggests the importance of timing of PLW infestation and may explain the lack of yield depression in relation to this pest observed in many field studies. Also, pea crops in soils with high levels of soil N are unlikely to be affected by this herbivore and should not require insecticide inputs.  相似文献   
66.
Reasons for performing study: There are currently few long‐term follow‐up data relating to recovery from injury of a collateral ligament (CL) of the distal interphalangeal (DIP) joint and limited information about the effect of associated osseous injury on prognosis. Objectives: To describe long‐term follow‐up results for horses with CL injury, with and without associated osseous injury; and to determine the effect of extracorporeal shock wave therapy (ECSWT) or radial pressure wave therapy (RPWT) on outcome. Hypotheses: Prognosis for return to performance for horses with CL‐related osseous injury would be worse than for horses with CL injury alone. Methods: Magnetic resonance images from 313 feet of 289 horses with foot pain and a definitive diagnosis of collateral desmopathy of the DIP joint were analysed retrospectively for presence of osseous abnormality associated with the ligament origin or insertion and the middle and distal phalanges. Horses were assigned to groups according to the combination of their injuries. Type of treatment was recorded and follow‐up information obtained. Thirty‐two horses with additional sources of lameness were excluded from analysis of outcome. Results: Follow‐up data were available for 182 horses, 55 of which had follow‐up information for up to 2 years after presentation. Twenty‐seven percent of horses with CL injury alone and 34% of horses with CL related osseous injury returned to their previous performance level. Prognosis for a combination of injuries to multiple soft tissue and osseous structures within the hoof capsule was substantially worse. There was no effect of ECSWT or RPWT on outcome. Conclusions: The presence of mild to moderate CL related osseous injury does not appear to influence prognosis compared with CL injury alone. Clinical relevance: Further studies of a larger number of horses are necessary in order to ascertain if specific types of osseous pathology influence return to performance levels.  相似文献   
67.
米勒时间     
企业扩张、兼并及战略调整,如同行船时方向调整一样需要一个过渡期,这个过渡期在米勒啤酒品牌调整经历的过程中被称为“米勒时间”或者被曲棍球行家们称为“曲辊球效应”。通俗地告诫是,企业的扩张行为需要时间,需要考虑原有的产品市场……  相似文献   
68.
Plantation success in northeastern Oregon can be limited by poor survival for western larch (Larix occidentalis Nutt.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. glauca (Beissn.) Franco) seedlings. Vegetation management treatments may increase soil moisture availability during the dry summer months, thereby increasing the probability of seedling survival. Chemical site preparation treatments were applied in spring 2007, summer 2007, and spring 2008 to determine if such treatments would improve survival and growth of bareroot Douglas-fir and bareroot and plug western larch seedlings on three sites near Elgin, Oregon. Although some herbicide treatments significantly increased survival, results were not consistent among sites. Overall, Douglas-fir had greater survival after 7–8 years than larch seedlings. Seedling size 7–8 years after planting was also highly variable among sites and treatments with larch seedlings being taller and larger than Douglas-fir seedlings, on the average. Size for all stock types was negatively correlated with vegetative cover and positively correlated with first-year soil moisture. Macro- and microclimatic conditions, including topography and soil depth, were likely contributors to differences in survival and growth.  相似文献   
69.
This report describes a suspect case of West Nile virus (WNV) encephalomyelitis, reported for the first time in a horse in the UK. The affected gelding had been imported from the Republic of Cyprus and travelled through several WNV endemic areas in Europe before arriving at the premises in Lincolnshire. Clinical signs included muscle fasciculations, weakness of the hindlimbs and transient lip twitching that quickly progressed to depression and recumbency. West Nile virus specific antibodies were detected by serological tests in the absence of a previous history of vaccination. The horse improved clinically 10 days after the onset of disease and fully recovered in 12 weeks. Follow‐ups at 12 and 20 months post event did not reveal any sequela and the horse was performing adequately at novice level. This article refers to the same horse mentioned by Fooks et al. (2014) and it is an extension of the previous published work.  相似文献   
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