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In a field experiment, the effects of different management treatments on the botanical development and productivity of a previously species‐poor, intensively managed, lowland permanent grass sward were investigated over a 4‐year period. Fertilizer inputs were stopped and nine main treatments, based on three pre‐sowing and three post‐sowing cutting regimes, were applied. Half of each treatment plot was oversown with a mixture of forb (wildflower) species and half left unsown. The aims were: (1) to investigate the effect of cutting regimes on the establishment of introduced forb species, (2) to assess the development and dry‐matter (DM) yield potential of these introduced species, and (3) to compare the DM yield and forage quality of swards with and without introduced species. Seedling establishment was recorded until the end of the second year. From the third year onwards, a common twice‐yearly cutting regime was imposed on all treatments, and the development of the introduced species was recorded. The DM yield of the nine oversown sub‐treatments was compared with the sub‐treatments not oversown. Frequent cutting after oversowing resulted in the greatest number of established plants and three times greater harvested DM yield of introduced species, compared with infrequent cutting. Plantago lanceolata and Trifolium pratense were the best performing introduced species. By years 3 and 4, there was proportionately 0·15 and 0·23, respectively, additional herbage DM yield harvested from the oversown treatments compared with unsown treatments, and up to 0·60 more in some treatments. The introduction of forbs increased the crude protein concentration, but decreased the digestibility of the forage. 相似文献
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In piglets, the influence of the ingestion of Fe-enriched faeces, of the oral application of Fe-dextran (containing 150, 200 or 250 mg Fe) up to the 8th hour as well as the intramuscular injection of Fe-dextran (150 mg Fe) on the 2nd and 3rd day after birth on Fe-resorption was analysed. On the 5th to the 7th and on the 12th to the 14th day after birth the highest increase in the Fe-concentration and the highest values of the Fe-binding capacity of the plasma after the oral application of a solution of Fe-sulphate (containing 20 mg Fe/kg body weight) were confirmed in the piglets with the ingestion of Fe-enriched faeces and in the control piglets without Fe-supplementation. The increase of the iron concentration in the plasma induced a decrease in the concentration of Cu in some cases and of Zn in the plasma in most cases. The biggest increase in body weight was established in the piglets that ingested Fe-enriched faeces. 相似文献
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A total number of 30 native breed cows were used in this investigation. Ten animals were clinically healthy and kept as control, while 20 diseased cows were selected according to rectal findings. At the beginning of the disease, the cows appeared obese with marked deposition of fat in the subcutaneous tissue at the lumbosacral area, later on they became emaciated. Additional signs were digestive disturbance in form of diarrhea or constipation and tympany. Rectal examination revealed hard irregular masses of various size which were palpated in the pelvis, the perirenal area around the colon and the rectum. More information about the nature and character of the lesions were taken from slaughtered cows. Biochemical analysis, including total lipids, cholesterol triglycerides and creatine kinase, were carried out in both healthy and diseased cows. In advanced cases of bovine lipomatosis hyperlipemia and hypercholesterolemia as well as increased creatine kinase values were constant findings. The aetiology of this disease is still unknown. 相似文献
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Description and Biomechanical Comparison of a Percutaneous Radiologic Gastropexy Technique in a Canine Cadaver Model
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