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Virmantas Povilaitis Alvyra Šlepetienė Jonas Šlepetys Sigitas Lazauskas Vita Tilvikienė Kristina Amalevičiūtė 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2016,66(3):259-266
This study aimed to investigate the productivity of two C3 legumes – alfalfa (Medicago sativa L.) and fodder galega (Galega orientalis Lam.) – and the feasibility of their use as renewable energy resources. Maize (Zea mays L.), a well-established bioenergy crop belonging to the C4 plant group, was used as a baseline in comparison. Field trials were conducted at the Institute of Agriculture at the Lithuanian Research Centre for Agriculture and Forestry during the period 2012–2013. The perennial forage legumes were grown without mineral or organic fertilizers. The maize was grown (a) without and (b) with nitrogen fertilizers. The perennial forage legumes were harvested three times per growing season. Carbon (C), nitrogen (N) and sulphur (S) contents of biomass were determined by using a dry combustion method. The calorific value of biomass was determined by a combustion method using an IKA bomb calorimeter. The largest share of the total annual yield of biomass of perennial forage legumes was obtained from the first cut and amounted to 54% and 57% for alfalfa and fodder galega, respectively. The S content of biomass was similar in all crops investigated, but the N content was higher in perennial forage legumes. Biomass C content did not differ between the crops, but the C:N ratio was widely varied – from 28–35 in fertilized maize, to 16–17 in alfalfa and 15–16 in fodder galega. This study showed that alfalfa and fodder galega can be grown as energy crops under less intensive management; however, the specific chemical composition of biomass should be considered before choosing the most appropriate conversion process. 相似文献
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Timmann D Cizinauskas S Tomek A Doherr M Vandevelde M Jaggy A 《Journal of Feline Medicine and Surgery》2008,10(1):9-15
Seizures have been reported frequently in feline infectious peritonitis (FIP) but have not been studied in detail in association with this disease. The purpose of this study was to perform a retrospective analysis of neurological signs in a population of 55 cats with a histopathologically confirmed neurological form of FIP. Seizure patterns were determined and it was attempted to relate occurrence of seizures with age, breed, sex and neuropathological features. Fourteen cats had seizure(s), while 41 cats had no history of seizure(s). Generalised tonic-clonic seizures were seen in nine cats; and complex focal seizures were observed in four patients. The exact type of seizure could not be determined in one cat. Status epilepticus was observed in one patient but seizure clusters were not encountered. Occurrence of seizures was not related to age, sex, breed or intensity of the inflammation in the central nervous system. However, seizures were significantly more frequent in animals with marked extension of the inflammatory lesions to the forebrain (P=0.038). Thus, the occurrence of seizures in FIP indicates extensive brain damage and can, therefore, be considered to be an unfavourable prognostic sign. 相似文献
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AbstractExpansion of grain maize to marginally suitable cool climate regions requires a better understanding of the nitrogen (N) economy of the crop. This study was aimed at yield formation in response to different type of fertilizers. Field experiments with short-season maize variety were conducted in Akademija, Lithuania, in 2015 and 2016. In spring, before sowing, ammonium nitrate, pelletized cattle and poultry manures, green waste compost were incorporated at a rate equivalent to 170?kg N ha?1. Crop N status, based on SPAD measurements, started to differ significantly at the end of the vegetative period with higher values in treatments applied with ammonium nitrate and lower with organic fertilizers. Under favorable conditions maize produced more grain per cob and higher yield. Agronomic N use efficiency (AEN) of pelletized organic fertilizers in the unfavorable season (AEN 2015: 0.1–4.9) was poor and significantly lower than in the favorable season of (AEN 2016: 4.9–11.2). 相似文献
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Johanna M Antila Janis Jeserevics Mindaugas Rakauskas Marjukka Anttila Sigitas Cizinauskas 《Acta veterinaria Scandinavica》2013,55(1):47
A six-year-old Ragdoll cat underwent examination due to a six-month history of slowly progressive gait abnormalities. The cat presented with an ambulatory tetraparesis with a neurological examination indicating a C1-T2 myelopathy. Radiographs of the spine showed a radiopaque irregular line ventrally in the vertebral canal dorsal to vertebral bodies C3-C5. In this area, magnetic resonance imaging revealed an intradural extramedullary/extradural lesion compressing the spinal cord. The spinal cord was surgically decompressed. The cause of the spinal cord compression was dural ossification, a diagnosis confirmed by histopathological examination of the surgically dissected sample of dura mater. The cat gradually improved after the procedure and was ambulating better than prior to the surgery. The cat’s locomotion later worsened again due to ossified plaques in the dura causing spinal cord compression on the same cervical area as before. Oral prednisolone treatment provided temporary remission. Ten months after surgery, the cat was euthanized due to severe worsening of gait abnormalities, non-ambulatory tetraparesis. Necropsy confirmed spinal cord compression and secondary degenerative changes in the spinal cord on cervical and lumbar areas caused by dural ossification. To our knowledge, this is the first report of spinal dural ossification in a cat. The reported cat showed neurological signs associated with these dural changes. Dural ossification should be considered in the differential diagnosis of compressive spinal cord disorders in cats. 相似文献
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Virmantas Povilaitis Sigitas Lazauskas Šarūnas Antanaitis Dalia Feizienė Virginijus Feiza Vita Tilvikienė 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(1):86-95
Purpose: The current study was aimed to analyse the occurrence of water and nitrogen stress in spring barley and estimate their effects on the crop performance under low-input and conventional management.Materials and methods: Field experiments were conducted during 2007–2009 at the Institute of Agriculture, Lithuanian Research Centre for Agriculture and Forestry on a sandy-loam soil. The management systems were: (a) conventional, with the application of fertilizers and pesticides adjusted to target 5 t ha?1 grain yield; and (b) low-input, without fertilizers and pesticides. Biomass and nitrogen concentration, leaf area index, soil moisture, drainage water runoff and ground water table were measured periodically during the growing season.Results: In all three experimental years, the annual precipitation was close or above the climate normal, but a large part of the rainfall (up to 310 mm) was lost through drainage contributing to the occurrence of temporary moisture deficit in late spring or summer. Water stress resulted in a lower spring barley biomass accumulation rate and lower biomass yield in the years characterized by sub-optimal rainfall distribution. Direct measurements of water retention in the soil and DSSAT model simulations gave relatively good indication of water stress occurrence. Under the low-input management, nitrogen nutrition level was a major constraint for spring barley biomass and grain yield formation.Conclusions: Under Central Lithuania’s conditions, spring barley frequently experiences temporary water stress, because a relatively high proportion of annual precipitation is lost during the non-growing period. This crop can benefit from anticipated increased precipitation and carbon dioxide levels if adequately provided with nitrogen. 相似文献