111red clover was introduced in the European agriculture approximately 1000 years ago in andalusia, Spain and from there, its cultivation spread to other countries (Kjaergaard 2003). in the territory of the Czech republic, the red clover has been intentionally grown already for 280 years (seed purchase was first mentioned to occur in 1730) and its contribution to the intensification of cattle rearing and production of cereals has been significant (lom 1937). Before the discovery of synthetic production of nitrogen from the atmosphere in 1909 by German chemist Fritz Haber, the main source of nitrogen for agricultural crops was symbiotic fixation of red clover and other legumes. The production of synthetic n fertilizers markedly increased after World War ii, which resulted in a rapid shrinkage of red clover cropland in Europe and north america (taylor 2008). The size of clover crop fields continues to diminish on a global scale. according to rochon et al. (2004), the size of clover crop fields in Europe lessened from 9.5 million ha in 1980 to 6.0 million ha in 2000.at the present time, we can see a certain increase of interest in growing forage legumes including red clover because of increasing energy costs and deteriorating environmental effects of synthetic nitrogen use. another reason for the greater interest in clover crops is an increasing significance of organic farming and increased price of protein concentrates after prohibition of meat-bone meals in feeding animals.red clover is the most important clover crop on moist, less fertile and acidic soils while alfalfa predominates in drier regions on deep soils with neutral reaction. although the forage of alfalfa contains more crude protein as compared with red clover, the advantage of red clover is the presence of enzyme polyphenol oxidase (PPo), which improves protein efficiency during digestion of ruminants (Sulivan and Hatfield 2006) and suppresses proteolysis during forage ensiling (Pahlow 2003). red clover is suitable in mixtures with grasses that enhance ensiling capacity and reduce damage to Effect of provenance and ploidity of red clover varieties on productivity, persistence and growth pattern in mixture with grasses S. Hejduk, P. Knot Department of Animal Nutrition and Forage Production, Mendel University in Brno, Brno, Czech RepublicAbStrAct in temporary and permanent grasslands, red clover distinctly increases herbage quality and production at low fertilization requirements. Main disadvantage of this species is its insufficient persistence. There are considerable differences in persistence among varieties, which are connected with different adaptability and disease resistance. in this experiment, we assessed the production of dry forage, number of plants and growth differences in eight tetraploid and fourteen diploid varieties grown in mixture with grasses. The highest production of forage for both harvest years was achieved by Czech varieties Spurt and amos and by Swiss variety Milvus. The lowest forage production was recorded in both years in Sw...

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BackgroundDevelopment of new nanomaterials that inhibit or kill bacteria is an important and timely research topic. For example, financial losses due to infectious diseases, such as diarrhea, are a major concern in livestock productions around the world. Antimicrobial nanoparticles (NPs) represent a promising alternative to antibiotics and may lower antibiotic use and consequently spread of antibiotic resistance traits among bacteria, including pathogens.ResultsFour formulations of zinc nanoparticles (ZnA, ZnB, ZnC, and ZnD) based on phosphates with spherical (ZnA, ZnB) or irregular (ZnC, ZnD) morphology were prepared. The highest in vitro inhibitory effect of our NPs was observed against Staphylococcus aureus (inhibitory concentration values, IC50, ranged from 0.5 to 1.6 mmol/L), followed by Escherichia coli (IC50 0.8–1.5 mmol/L). In contrast, methicillin resistant S. aureus (IC50 1.2–4.7 mmol/L) was least affected and this was similar to inhibitory patterns of commercial ZnO-based NPs and ZnO. After the successful in vitro testing, the in vivo study with rats based on dietary supplementation with zinc NPs was conducted. Four groups of rats were treated by 2,000 mg Zn/kg diet of ZnA, ZnB, ZnC, and ZnD, for comparison two groups were supplemented by 2,000 mg Zn/kg diet of ZnO-N and ZnO, and one group (control) was fed only by basal diet. The significantly higher (P < 0.05) Zn level in liver and kidney of all treated groups was found, nevertheless Zn NPs did not greatly influence antioxidant status of rats. However, the total aerobic and coliform bacterial population in rat feces significantly decreased (P < 0.05) in all zinc groups after 30 d of the treatment. Furthermore, when compared to the ZnO group, ZnA and ZnC nanoparticles reduced coliforms significantly more (P < 0.05).ConclusionsOur results demonstrate that phosphate-based zinc nanoparticles have the potential to act as antibiotic agents.Electronic supplementary materialThe online version of this article (10.1186/s40104-019-0319-8) contains supplementary material, which is available to authorized users.

In 2004-2009, a small-plot trial was conducted on permanent grassland dominated by Festuca arundinacea Schreb. on the mesohygrophytic site in order to evaluate effects of four levels of nutrition: F 1 = without NPK fertilization, F 2 = P 30 + K 60 , F 3 = N 90 + P 30 + K 60 , F 4 = N 180 + P 30 + K 60 kg/ha), four levels of cutting intensity (I 1 -4, I 2 -3, I 3 -2, early, I 4 -2, late cut) and their interactive influence, i.e. a total of 16 variants on the production of forage dry matter, production of crude protein (CD) and net energy of lactation (NEL) per hectare. The dominant influence of N-nutrition is documented by significant differences in forage dry matter (DM) production between the variants (with the exception of F 1 /F 2 ) ranging from 4.41-4.80 to 8.44-9.83 t/ha. The effect of different exploitation level on the production is subdominant and no significant differences were found either in the production of forage DM (I 1 -6.41 -I 2 -6.59 -I 3 -6.97 -I 4 -7.50 t/ha) or in the production of nutrients. Management models to be recommendeed for the given type of sward with respect to the interactive influence, efficacy of forage production and quality are as follows: (a) three cuts/180 kg N + PK/ha with forage suitable for dairy cows; (b) two cuts/90 kg N + PK/ha with forage suitable for cattle breeds kept for meat.

The effect of fertilization and the harvest frequency on production and floristic characteristics of a meadow stand were assessed in a small plot trial established in 2003 in Vatín, Vysočina Region, the Czech Republic. Four levels of fertilization (none; N0 + P30 + K60 kg∙ha−1; N90 + P30 + K60 kg∙ha−1; N180 + P30 + K60 kg∙ha−1) were combined with four treatments of exploitation intensity (4 cuts per year, first cut on 15th May, every next after 45 days; 3 cuts per year, first cut on 30th May, every next after 60 days; 2 cuts per year, first cut on 15th June, next after 90 days; 2 cuts per year, first cut on 30th June, next after 90 days). Production of dry matter and proportions of guilds (grasses, legumes, and other species) were evaluated. Data from 2009–2011 were used in this paper. Yields of the dry matter increased along with increasing amounts of nutrients supplied and ranged from 3.8 t∙ha−1 (non-fertilized) to 9.1 t∙ha−1 (N180PK). The nutrition level had a significant effect on spread of grasses, which reached maximal proportion of 52.3 % under N180PK fertilization compared to 42.1% on non-fertilized plots. On the contrary, legumes flourished well in treatments without N-supply, attaining proportion of 6.8 % and 5.1 % on PK-fertilized and non-fertilized plot, respectively. With regard to the exploitation intensity grasses profited from extensive management by contrast to the group of other species which reached its maximum in swards harvested four times a year. Proportions of legumes did not show significant dependence on the cutting frequency.