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31.
Piotr Ostaszewski Agnieszka Kowalska Ewa Szarska Piotr Szpotański Anna Cywinska Bożena Bałasińska Tomasz Sadkowski 《Journal of Equine Veterinary Science》2012
In both the horse and the man, nutritional ergogenic aids have been used to improve physical ability in conjunction with an appropriate training regimen. Although training increases physical condition, the ease of taking a nutritional additive to improve training results explains the demand for supplementation, which may increase mechanical energy of work, delay onset of fatigue, or improve neuromuscular coordination. The purpose of this study was to determine the effects of oral supplementation of β-hydroxy-β-methylbutyrate (HMB) and γ-oryzanol (GO) on indices of exercise-induced muscle damage in Thoroughbred race horses. In this 32-week study, the horses were assigned to either a placebo, GO (3.0 g/d), HMB (15 g/d), or GO and HMB treatment groups. The supplements were administered for the first 16 weeks of the study during the training period before the racing season began. Blood samples were taken at baseline, and then during training, before exercise, immediately after exercise, and 30 minutes after exercise. Heart rate and speed were monitored in each exercise session. Hematocrit, glucose, lactate (LA), creatine phosphokinase, and aspartate aminotransferase were measured before and after each exercise session. Analysis of variance showed a significantly greater increase in postexercise creatine kinase activity in placebo-supplemented group than in the other treatment groups, both in the training period and during the racing seasons (P < .05). Blood LA was higher immediately after exercise in the placebo group compared with the supplemented groups. In conclusion, supplementation with HMB and GO resulted in decreased creatine kinase and LA after exercise. These findings support the hypothesis that HMB and GO supplementation helps to prevent exercise-induced muscle damage. 相似文献
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配方施肥对皮燕麦地上生物量和种子产量的影响 总被引:1,自引:0,他引:1
以青引1号燕麦为研究对象,研究施肥对燕麦地上生物量和种子产量的影响。结果表明,从拔节期到成熟期,燕麦地上生物量,施肥处理高于对照CK处理,完熟期OPT处理最高,达99478.5 kg/hm2。施磷能显著提高燕麦种子产量。OPT+1/2P处理所得燕麦籽粒产量最大,为6678.3 kg/hm2。在施钾量和施磷量一定时,燕麦籽粒随施氮量的增加呈先增加后下降的趋势,OPT-1/2N处理所得籽粒产量仅低于OPT+1/2P处理,为6588.3 kg/hm2。 相似文献
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本试验旨在研究日粮中添加燕麦青干草粉对互助八眉二元母猪初生仔猪器官发育的影响.选取40头体况和胎次相近的互助八眉二元母猪作为试验动物,随机分为高纤维组、中纤维组、低纤维组和对照组(妊娠前期饲粮粗纤维水平分别为13.96%、11.02%、7.83%和4.33%,妊娠中期饲粮粗纤维水平分别为11.93%、9.26%、6.38%和4.33%).结果表明:1)肝脏指数高纤维组和中纤维组分别显著高于对照组(P<0.05),脾脏指数处理组极显著高于对照组(P<0.01);2)消化器官指数:胰脏指数高纤维组极显著高于对照组(P<0.01),中纤维组显著高于对照组(P<0.05);小肠指数高纤维组极显著高于对照组(P<0.01),中纤维组、低纤维组和对照组无显著差异(P>0.05);3)其他器官指数:心脏指数处理组极显著高于对照组(P<0.01),肾脏指数高纤维组和中纤维组均显著高于对照组(P<0.05);4)初生仔猪生产性能:对照组初生仔猪个体重最大,与中纤维组无显著差异(P>0.05);初生产仔数、初生产活仔数高纤维组和中纤维组极显著高于对照组(P<0.01);初生窝重中纤维组表现最好,显著高于对照组(P<0.05).综合分析认为,中纤维组母猪日粮(妊娠前期11.02%、妊娠中期9.26%)可显著促进初生仔猪器官的发育,并改善初生仔猪的生产性能. 相似文献
36.
German black headed mutton (GBM) ewes are recognized as being highly susceptible to ovine pregnancy toxemia (OPT). The present trial was performed to evaluate whether a breed-dependent gestational diabetes mellitus-like insulin resistance during late pregnancy might be responsible for the high incidence of OPT in the GBM breed. Modified frequently sampled intravenous glucose tolerance tests (300 mg glucose and 0.03 IU insulin per kg of BW) were performed during mid and late pregnancy, the periparturient, and the dry period in polytocous 3.5-yr-old GBM and Finnish Landrace (FL) ewes fed according to their requirements. The corresponding blood samples were analyzed for plasma concentrations of glucose, insulin, nonesterified fatty acids (NEFAs) and β-hydroxybutyrate (β-HB). In addition, the baseline plasma cortisol concentrations were determined during late pregnancy. The BW gain during pregnancy and the rearing success did not differ between the GBM and FL ewes. In both breeds, late pregnancy was associated with decreased basal plasma glucose concentrations and enhanced glucose disposal, as well as elevated baseline β-HB values. Only in the GBM ewes did the plasma NEFA concentrations increase significantly during advancing pregnancy. Moreover, significantly higher baseline plasma NEFA concentrations as well as lower (P < 0.05) basal plasma glucose values were recorded during late pregnancy in the GBM than in the FL ewes. The first-phase insulin secretion, the peripheral insulin sensitivity, and the baseline plasma cortisol values did not differ between both breeds during late pregnancy. It is concluded that increased lipolysis during late pregnancy is a characteristic of the GBM breed. Moreover, elevated plasma NEFA concentrations may contribute to impaired pancreatic insulin response and peripheral insulin resistance in GBM ewes and thus promote OPT. 相似文献
37.
Recent reports have indicated a role of cell-to-cell interactions during gonadal development and functions. Numerous reports indicate that fetal hormonal disruption induces abnormalities in the developing reproductive system and, therefore, may interfere with reproductive functions later in adult life. Hence, this study investigated the effect of androgen deficiency during late prenatal periods on the gap junction-associated connexin 43 (Cx43) and the adherens junction-associated β-catenin expression in the fetal porcine gonads. Thus, pregnant gilts were injected with anti-androgen flutamide (for 7 d, 50 mg/kg BW per day) or corn oil (control groups) starting at 83 (GD90) or 101 (GD108) gestational day. On GD90 and GD108 the fetuses were excised and fetal gonads were obtained. To assess Cx43 and β-catenin expression real-time PCR and immunohistochemistry were performed. In fetal testes, Cx43 was localized between Leydig cells, whereas β-catenin was observed mainly within the seminiferous tubules. In fetal ovaries, Cx43 was detected between interstitial cells and between granulosa cells of forming follicles, whereas β-catenin was found within egg nests, in oocytes' membrane, and in granulosa cells of forming follicles. Immunohistochemistry showed decreased Cx43 and β-catenin expression in fetal gonads from flutamide-treated pigs compared with respective controls. However, the ovaries from animals treated with flutamide on GD108 showed increased Cx43 expression. The changes of Cx43 and β-catenin expression after prenatal flutamide treatment were confirmed at the mRNA level. These findings suggest that androgen deficiency during late gestation may lead to disturbed intercellular interactions in fetal porcine testes affecting testicular functions, as well as impaired follicular formation in fetal ovaries. Our results further signify the role of androgens in the regulation of cell-to-cell interactions within fetal porcine gonads. 相似文献
38.
The determination of mash consistency proved to be difficult but is of great importance particularly with regard to process and quality control. Therefore, the aim of this study was to develop a new rheological method for precisely determining changes in mash consistency occurring during the mashing process. For that purpose, five mashes with various levels of unmalted oats (0–40%) have been analyzed using a Physica MCR rheometer equipped with a paddle-shaped rotor enabling mash particles to be kept in suspension throughout the rheological measurement. For validating this new method, a statistical comparison with the established Rapid Visco Analyser (RVA) has been carried out. For this purpose, the mash consistency curves have been described by regression functions with the aim to determine characteristic curve points mathematically correct. As a result, the start and end point of starch gelatinization/liquefaction have been well-defined. By calculating the coefficients of determination, good to very good linear correlations between respective curve values and adjunct levels have been found for both methods (MCR and RVA). By calculating the repeatability, however, it has been revealed that the precision of the MCR method is significantly better than that of the RVA method. 相似文献
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40.
Isabelle Le Viol Romain Julliard Louis de Redon Nathalie Machon 《Biological conservation》2008,141(6):1581-1590
Road verges should play a crucial role as a refuge for native flora and fauna in human dominated landscapes. However, the influence of construction choices, such as plantation of woody species, on the biodiversity supported by roadsides has received little attention, although the presence of hedgerows in roadsides is likely to enhance their role as a refuge, notably for woodland species. Using standardised methods, we assessed the impact of planted hedgerows on two taxonomic groups (plants and spiders) inhabiting highway verges within an intensive agricultural landscape. We examined community richness, taxonomic and functional composition in sites with and without planted hedgerows. At the site level, the response of plant and spider communities to the presence of planted hedgerows differed markedly: hedgerows were associated with significantly higher plant richness (higher α-diversity), but similar spider richness. Plant communities in sites without hedgerows appeared as a subset of communities in sites with hedgerows, whereas spider communities in non-planted sites were complementary to that of planted sites (increased β-diversity). The presence of planted hedgerows was also associated with increased taxonomic and functional trait diversity at the landscape level (γ-diversity), through an increased β-diversity in both plants and spiders. Our results thus suggest that a mosaic of planted hedgerows and grassland habitats is crucial for the maintenance of biodiversity at a landscape scale. By providing information for road practitioners and policy makers regarding their potential impact on biodiversity, these results have important direct implications for the management of road networks. 相似文献