ascorbate peroxidase ͉ chloroplast ͉ oxidative stress ͉ reactive oxygen species

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Milk from CSC-supplemented ewes was characterized by increased levels of beneficial nutritional factors, including mono- and n-3 polyunsaturated fatty acids, and was also by lower atherogenic and thrombogenic indices. Taking into consideration all the obtained results and recommended fat concentrations in a daily ruminant ration, we recommend supplementing a dairy ewe's diet with 30 g kg(-1) DM of CSC cake in practice.

Aim: Scots pine is one of the dominant tree species in forest ecosystems of the temperate and boreal zones in Eurasia. Since the Tertiary, it has persisted also in the Mediterranean region, forming relict populations. In this study, we investigate rangewide genetic diversity of Scots pine, aiming to provide comprehensive information on the phylogeography and genetic resources of the species.Location: Europe and Asia. Methods: Thirteen paternally inherited chloroplast microsatellite (cpSSR) loci were used to investigate the genetic structure of 62 populations from Fennoscandia and 30 populations from the Mediterranean. We also surveyed variability of two maternally inherited mitochondrial DNA (mtDNA) regions and additionally included literature data from 156 populations (248 populations in total).Results: Scots pine retains an overall high genetic diversity in the chloroplast genome but, unexpectedly, the historically younger populations from Fennoscandia showed statistically higher mean intrapopulation diversity than the Mediterranean stands (0.807 and 0.750, respectively). The latter also contained a lower number of private cpSSR haplotypes.Population differentiation with respect to mtDNA was higher (G ST = 0.628) than at cpSSR (G ST = 0.015) indicating an efficient pollen-mediated gene flow among refugial populations of the species. One novel haplotype mtDNA was found, increasing the number of known mitotypes for the species from 4 to 5. The geographic distribution of mitotypes was structured into four groups corresponding to the main refugial areas of the species. Main conclusions: Genetic impoverishment of the Mediterranean populations may enhance their vulnerability to future environmental changes. The spatial distribution of two mitotypes in Fennoscandia, featuring predominance of mitotype a in Norway and Sweden and mitotype b in Finland, gives strong support for dual colonization of that region from south-eastern (Finland) and south-western (Sweden) directions. These results thus provide new insights into both Holocene expansion of Scots pine and the present distribution of species' genetic resources. | 541 DERING Et al.

SUMMARYAlthough the effect of saponins or saponin-containing plants on rumen microorganisms and rumen fermentation has been intensively investigated, this issue still requires special attention. Many of the phenomena occurring in the rumen related to dietary saponin supplementation are still not fully understood. Saponaria officinalis is a triterpenoid saponin-containing plant; thus, the aim of the present study was to evaluate the effect of S. officinalis L. powdered root, methanolic extract of the S. officinalis root (SOR) and the effect of the separated fractions (polysaccharides, saponins and phenolics) of S. officinalis on rumen methanogenesis, microbial population and rumen fermentation characteristics in an in vitro batch culture fermentation system. The powdered root (raw plant material) and S. officinalis extract (SOE) decreased in vitro methane production and consequently reduced the microbial population in a dose-dependent manner. The inhibition of methanogenesis was accompanied by changes in the volatile fatty acids profile. In vitro dry matter digestibility was not affected by any of the secondary compounds applied. The highest applied doses of SOE caused a higher reduction in methanogenesis (33·5 v. 14·4%) than the highest doses of powdered root form. Such results suggest that the basic components of the SOR could interact with phytochemicals or that the phytochemicals became physically less available for microbiota, resulting in a decreased antimethanogenic activity of the powdered root v. the extract. Among all the fractions selected, the saponin fraction exerted the greatest impact on ruminal fermentation. In conclusion, saponins decreased methane production by 29% in comparison with the control. This decrease was related to the reduction in protozoa and methanogen counts. It is proposed that S. officinalis has the potential to inhibit rumen methanogenesis without affecting rumen fermentation adversely.

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