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421.
422.
Physiological responses and fruit quality of ‘d’Anjou’ pear fruit from five orchard lots were evaluated after cold storage in air or controlled atmospheres (CA) with the O2 concentration based on assessment of fruit chlorophyll fluorescence (CF) or standard conditions (1.5 kPa O2). The pCO2 for all CA fruit was 0.5 kPa. Softening, acid loss, and peel degreening of all lots were delayed at one or more evaluation dates (2, 4, 6, 8 months) by previous storage at the CF pO2 compared with fruit stored in 1.5 kPa O2 or in air. Superficial scald developed on fruit previously stored in air but not on fruit stored in a CA. Pithy brown core developed on fruit from all lots stored at the CF pO2 and on fruit stored at 1.5 kPa in 3 of the 5 lots. Pithy brown core incidence decreased with advanced harvest maturity. Post-storage ethylene and CO2 production were in most instances lowest for fruit stored at the CF pO2. A significant relationship between fruit ethanol content and pithy brown core incidence was observed. Results indicate low pO2 storage based on CF monitoring slows fruit ripening relative to fruit stored at 1.5 kPa O2, prevents superficial scald development compared with fruit stored in air, however, development of pithy brown core in fruit stored at the CF pO2 was not accompanied by a change in CF. 相似文献
423.
Tea is a rich source of antioxidants which are contributing substantially to the promotion of health and the prevention of
various chronic diseases. Despite the fact that tea has various important compounds, it also contains a purine alkaloid, caffeine.
High intake of tea leads to an increase in level of caffeine in addition to its important antioxidant constituents. Increased
level of caffeine causes several health related problems. Therefore, tea can become a most useful source of beneficial compounds,
if only its caffeine level is either decreased or eliminated all together from the plant itself. This could be achieved through
either of the techniques; overexpressing caffeine degradative pathway genes or silencing caffeine biosynthesis pathway gene.
The identification and cloning of caffeine biosynthesis in tea and degradative genes in microorganisms opens up the possibility
of using genetic engineering to produce naturally decaffeinated tea. Here we review these different strategies which can be
employed to make caffeine-free tea, a human health beneficial drink. 相似文献
424.
Guo H Ling W Wang Q Liu C Hu Y Xia M Feng X Xia X 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(1):1-6
This study was designed to evaluate the effect of an anthocyanin-rich extract from black rice on hyperlipidemia and insulin
resistance in fructose-fed rats. Rats fed fructose diet for 4 weeks exhibited significantly higher plasma insulin levels and
lower insulin sensitivity than the control rats fed AIN-93G diet. Dietary supplementation with the anthocyanin-rich extract
(5 g/kg of high-fructose diet) prevented the development of fructose-induced insulin resistance. After fructose-induced insulin
resistance had been established, 4-week treatment with the anthocyanin-rich extract (5 g/kg of high-fructose diet) or pioglitazone
(270 mg/kg of high-fructose diet) ameliorated the glucose intolerance and hyperlipidemia, but the extract failed to reverse
the fructose-induced hyperinsulinemia as pioglitazone did. In addition, rats supplemented by the extract exhibited lower oxidative
stress than the fructose-fed controls, as indicated by the lower concentrations of plasma thiobarbituric acid reactive substances
and blood oxidized glutathione. Overall, these results suggest that the anthocyanin-rich extract from black rice improves
certain metabolic abnormalities associated with diets high in fructose. 相似文献
425.
Prevalence of lameness and of associated claw disorders in Greek dairy cattle industry 总被引:1,自引:0,他引:1
The aim of this study was to assess the prevalence of lameness as well as the prevalence of claw–horn disruptions, abnormal claw shape and dermatitis in lame cows in Greek dairy farms and to evaluate their risk factors. Forty dairy farms were visited twice, during winter and during summer, and the lameness of milking cows was scored using a 5-point scale. In total 760 cows were lame (lameness score ≥ 3) and were further examined to identify macroscopically the claw disorders. The herd size, the trimming and footbathing frequency, the floor surface, the cleanness of the herd, the scraping frequency and the disinfectant used in the footbaths were recorded. The mean lameness prevalence was 18.7% and that of claw disorders observed in the lame cows was 75.4% for abnormal claw shape, 30.2% for dermatitis and 30.6% for claw–horn disruptions. Large herd size and the absence or only once per year trimming were associated with increased risk for the presence of lameness. 相似文献
426.
Reasons for performing study: Dental disorders have a high prevalence in older donkeys and horses, but the nature and pathogenesis of many of these disorders have yet to be established. Objectives: The identification and determination of the prevalence of important dental disorders in different age groups in a large single population of donkeys, to establish a better understanding of the nature and pathogenesis of these disorders. Methods: A prospective cross‐sectional study was performed on the donkey population at The Donkey Sanctuary with detailed oral examinations of 357 donkeys within 7 different age groups (age range 2–53 years) recorded. Results: The prevalence of dental disease in all donkeys was 73%, increasing in prevalence from 28% in the youngest to 98% in the oldest age group. There was an increase in prevalence of commonly recognised dental disorders with increasing age, such as: diastemata (3.8% in youngest to 86% in oldest group); missing teeth (0–56%); overgrown teeth (15–86%); worn teeth (8–84%); displaced teeth (0–38%); and periodontal disease (0–28%). Conclusions: There was a significant increase in the prevalence of dental disorders with increasing age with the largest significant increase for most dental disorders occurring in the 15–20 year age group. Potential significance: Most dental disorders significantly increase in prevalence in the 15–20 year age group and, therefore, prophylactic geriatric dental treatment in donkeys should be commenced from age 15 years. 相似文献
427.
Inherited diseases of Australian Holstein-Friesian cattle 总被引:1,自引:1,他引:0
428.
Sbastien Assi Nathalie Bareille Franois Beaudeau Henri Seegers 《Preventive veterinary medicine》2009,91(2-4):218-225
Our aim was to determine at calf-batch level the management- and housing-related risk factors of respiratory disorders in non-weaned Charolais calves. Farmers recorded cases according to the definition provided i.e. the association of at least one respiratory sign and, in the same calf or another calf of the same batch, at least one general sign on the same day or the day before. During farm visits, quality of farmers’ records was checked and questionnaires were applied to gather farm and herd characteristics and to describe farming practices and housing facilities. Data were suitable for analysis for 172 batches where no metaphylactic treatment was implemented. Batches had great disparity in incidence of respiratory disorders. In the 120 batches with at least one case, the quartiles of incidence rate were, respectively, 0.95, 2.15 and 3.59 cases per 1000 calf-days at-risk. For risk-factor analysis, the statistical unit was the calf-batch located in a given batch. We used a ZINB model because (i) there was significant overdispersion of incidence rates of respiratory disorders (overdispersion test statistic of O = 1049 (P < 0.001)), (ii) probability was high that a two-group modelling process existed (Vuong statistic of V = 2.44 (P = 0.0073)) and (iii) the ZINB model fit significantly better than the ZIP model (likelihood-ratio statistic of 340.14 (P < 0.001)). The risk was higher in open-fronted barns or in open barns compared to closed ones (incidence-rate ratios (IRRs): 1.9 and 1.8), in barns where no annual disinfection was implemented (IRR: 1.5) and in part slope with straw/part scraped and in part straw-bedded/part scraped barns compared to completely straw-bedded barns (IRRs: 1.9 and 1.6). Larger calf-batches were more at-risk than smaller batches (OR for the effect of an increase of 10 calves on the probability of a 0 count: 0.5). 相似文献
429.
Attia YA Hussein AS Tag El-Din AE Qota EM Abed El-Ghany AI El-Sudany AM 《Tropical animal health and production》2009,41(4):461-475
In order to study the influence of lecithin and vegetable oils on improving productive and reproductive performance, egg quality,
and metabolic profile of dual-purpose crossbred hens in the tropics, a total of 224 hens, 47-wk old, 112 each of Gimmizah
and Silver Montazah strains were fed seven isonitrogenous diets. Experimental treatments consisted of feeding seven different
diets to layers; four isocaloric diets containing either no added lipid (control), 3% vegetable oil mixture, 3% soy lecithin
or 6% soy lecithin; and three high-energy level diets, containing an extra 3% vegetable oil mixture, 3% or 6% soy lecithin
added to the control diet. Thus, the experimental design was factorial, consisting of seven lipid treatments by two strains
of hens. Results indicate that 3% lecithin as an extra ME source, or feeding 11.72 MJ ME/kg diet containing the same level
of lecithin, improved productive and reproductive performance of crossbred hens. Moreover, lecithin at 6% as an extra ME supplement
significantly increased yolk percentage and improved Haugh unit score and yolk color, while increasing EE digestibility and
plasma total lipids. Hen strain had a significant effect only on digestibility of OM, percentage liver and Haugh unit score,
with the Gimmizah strain having higher values. 相似文献
430.