Zorica Nesic

Perennial legumes and grasses stable source of quality livestock fodder feed

Perennial legumes, alfalfa, red clover, birds foot trefoil, white clover, sainfoin and grasses, cocks foot, meadow fescue, tall fescue, Italian ryegrass, English ryegrass, French ryegrass, red fescue and Timothy grass can be grown successfully in pure crops and in legume-grass mixtures, on different soil types. Their importance in livestock development is based primarily on the great potential for yield of dry matter of over 20 t ha-1 if adequate agro-technical measures have been applied. Also, perennial legumes are characterized with high content of nutritive substances, especially protein and represent the most important protein source in livestock nutrition. Depending on the species and pheno stage of utilization, the content of crude proteins in grasses varies from 100 to 174,6 g kg-1 of DM, and in perennial legumes from 190,0 to 228,8 g kg-1 of DM. Livestock feed obtained from these plant species can be used in several ways, from grazing as most efficient and economical way, to preparation of hay and high quality silages and haylages. Stated forage species are very important in sustainable agriculture and organic production, considering that they carry out the process of biological fixation of nitrogen, but also from the ecological aspect. By using diverse selection/breeding material numerous domestic cultivars of perennial legumes and grasses have been created which are characterized with high potential for main agronomical traits.

NITRATES IN PLANTS AND SOIL AFTER FERTILIZATION OF GRASS-LEGUME MIXTURES **

Nitrates are one of the most frequent utilized forms of N from soil. Through root they reach stem and leaf where in photosynthetic processes they convert into proteins. Due to exposure to stress situations, and excessive nitrogen fertilization, nitrate accumulation in plant tissues and organs occurs. Also, nitrates can accumulate in harmful concentrations in soil. Nitrates accumulated in plants have harmful effect on animals which consume plants since they cause various health disorders. In variance analysis in both investigation years it was established that fertilization as well as interaction of factors mixture/fertilization had very significant effect on investigated quality parameter, contrary to mixture as single factor. In both investigation years, treatments with 210 kgN ha-1 had the highest nitrate concentration. Content of nitrate nitrogen in soil is increased by fertilization. Objective of the research was to determine nitrate quantities which are accumulated in plants subsequent to n fertilization and growing in mixtures with other species, as well as to determine nitrate quantities which remain in the soil unutilized, which are potential causes of environment pollution.

Parameters of production and quality of new cultivars of perennial leguminous plants as livestock feed

This paper presents the results obtained in testing of new selection of four most important and most common species of legumes used for animal feeds in Serbia. Alfalfa, red clover, birds trefoil and sainfoin are also high quality plants regarding both nutritive substances and yield of dry matter. We have investigated three new selections of alfalfa, two selections of red clover, two selections of birds trefoil and one of sainfoin in relation to standard ones. Trial lasted two years (2003-2004), designed according to standard methods for testing and recognition of new sorts. The production of green mass through four cuts per year was determined, together with the variation coefficient among cultivars. In the cuts of the second year the quality parameters were determined by standard lab analyses. The content of protein in all three new selections of alfalfa was higher in relation to standard (16,01%). while the standard of red clover with 20,03% was better than new selection. New selections of birds trefoil are of better quality than standard (22,08 %), which is the case also with sainfoin (19,71 %). On the basis of obtained production and quality parameters the assortment of perennial legumes will be enriched by new cultivars.

The effect of protein source in diet on production performances of fattening lambs

Research was carried out on experimental sheep farm of the Institute for Animal Husbandry, Belgrade-Zemun. Trial included 60 lambs - crosses of F1 generation of Pirot Pramenka x Wurttemberg x Ile de France weaned at the age of 60 days. Nutrition treatment included study of three concentrated mixtures which were different in protein source (sunflower, soy bean and fish meal), i.e. share of proteins non-degradable at the level of reticulo-rumen: 43 (I) : 51 (II) : 58%(III). The effect of stated treatment in intensive fattening of lambs was monitored through production parameters. Obtained data was processed using standard statistical analysis. Average body mass of lambs at the beginning of trial, in treatments I: II: III was: 18,08: 18,12: 18,17 kg. After fattening of 75 days, final body mass of lambs in analogous treatments was: 30,78 (I) 33,52 (II) 35,17 kg (III) and average daily gain: 0,169: 0,205 : 0,227 kg. Per kilogram of realized gain of lambs, in analogous treatments, the following was consumed: 4,54 : 3,71 : 3,30 kg of dry matter of diet; energy: 33,77: 29,37 : 26,25 MJ; total proteins: 732 : 596 : 549 g. Research demonstrated that protein source in concentrate mixtures used in nutrition of fattening lambs (i.e. share of nondegradable protein in total proteins)had significant effect on production parameters, and the best performance was registered in lambs on treatment with fish meal (share of NP was 58%).

Harmful plant species in meadow-pastures associations on Stara Planina mountain

Meadows and pastures are important resource of livestock feeds in mountain regions and all plant species on them don’t have same value as livestock feeds. From aspect of food value for livestock all species fundamentally can distribute as useful and harmful plants. In paper are represent two plant associations of Stara Planina Mountain Festucetum vallesiacae and Agrostietum vulgarae. In this associations, besides useful plants, are defined, harmful plant species, there present in associations and all of it in aim of ascertainment measures for their removal or reduction from sward. Group of harmful plants is segmented on three subcategory: bed and worthless plants, harmful and poorly poisons and very poisons plants. Association Festucetum vallesiacae count 75 plant species and of that, category bed and worthless plants belong 26 plants or 34.7 g kg-1, category harmful and poorly poisons belong 8 or 10.6 g kg-1, while category very poisons plants default. Association Agrostietum vulgare count 47 plant species and of that category bed and worthless plants belong 17 or 36.17 g kg-1, category harmful and poorly poisons just one plant or 2.13 g kg-1 and category very poisons plants default too.

Nutrition as factor of improvement of production of sheep milk on the territory of Stara Planina mountain

Investigation was carried out on the territory of Stara Planina mountain, Pirot mnucipality, in villages: Dojkinci, Brlog, Jelovica, Visocka Ržana and Rsovci, from 700-1200 m above sea level, on farms with greater number of sheep (over 100 heads) which in regard to the breeds structure were mainly Pirot pramenka breed, and insignificant number of heads were crosses of Pirot Pramenka and Wurttemberg. Research included analysis of pasture from the aspect of floristic and chemical composition. In regard to botanical composition it was concluded that grasses were present with approx. 50%, leguminous plants with 15% , and herbaceous plants with 35%. Share of crude protein in investigated samples varied from 4,81 to 13,57%, and of crude fibre from 20,67 to 37,17%. Yield of forage on pastures was from 0,6 to 2,0 t/ha. Low yield as well as unsatisfactory floristic composition of pastures resulted from poor care, especially lack of fertilization and their unplanned and inefficient use which was reflected on milk yield of sheep, in lactation of 180 days it was from 69,16-70,40 kg. Improvement of botanical composition can be achieved by application of fertilizers since in this way the share of useful grasses (Poaceae) and leguminous plants (Fabaceae) is increased, and share of herbaceous plants in total mass of pasture is reduced, which represents one of our goals in research on the Pirot territory of Stara Planina mountain. In order to preserve the quality and phytodiversity of plant species we suggested as optimal way of pasture utilization, combination of pasture and cutting system. In winter nutrition period, on investigated locations, introduction of haylage in nutrition of sheep used for production of milk is recommended, because of its higher nutritive value compared to hay.