Goran Grubic

The influence of zeolite on the quality of fresh beet pulp silages

The influence of different doses of natural zeolite addition on chemical composition and quality of beet pulp silages was investigated. Beet pulp was ensiled in the sugar factory in Požarevac immediately after they were obtained, or after 9 or 17 days. The two-factorial trial was conducted where the first factor (A) was the time of ensiling expressed in days after the pulp was obtained (a1= O; a2 = 9; a3 = 17), while the second factor (B) was the amount of zeolite added (b1= 0; b2 = 0.05; b3 = 0.25 and b4 = 1.25% in dry matter or 0; 50; 250 and 1250 g zeolite per 100 kg of raw beet pulp). Sample collection for standard chemical composition and quality estimation was taken 60 days after the beginning of the ensiling. The results from the literature show that adding technologically processed natural zeolite (Min-a-Zel, produced by ITNMS, Belgrade) while ensiling beet pulp has significant influence on the increase of lactic acid production, decrease in bonded acetic acid content and lower pH value. The influence of explained doses of zeolite on standard chemical composition is smaller and mostly of relative value. The only real changes in chemical composition are the increase in dry matter and mineral content. In the ensiling of the beet pulp stored in the longer period of time, the more intensive fermentation processes were achieved and the production of organic acids was larger which has better conserving effects on silage.

137Cs and 40K in some traditional herbal teas collected in the mountain regions of Serbia

Herbal teas are an important part of traditional medicine in Serbia. The objective of the present study was to determine the activity concentrations of 40K and 137Cs in herbal tea, using the gamma spectroscopy method. The samples were collected during the period 2011–2012 in three mountain regions in Western and Central Serbia. The activity concentrations of 40K and 137Cs were found to be in the range of 130–1160 and 0.7–124 Bq kg−1, respectively. The average annual effective dose equivalents from ingestion of 40K and 137Cs for an adult person consuming one cup of herbal tea daily were found to be 588.4–5250.2 nSv for 40K and 4.0–706.1 nSv for 137Cs. Our investigation showed that the herbal teas originating from Maljen, Zlatibor and Tara mountains are radiologically safe for human consumption.

SOCIAL, ECONOMIC, FISHERY AND CONSERVATIONAL ISSUES FEATURING FLY FISHING COMMUNITY IN SERBIA

Modern fly fishing, mainly for brown trout and grayling, has been done on a local scale and in low extensity in Serbia for over 50 years. Data obtained from 117 fly fishermen filling out an online questionnaire, with 30 questions processed using multivariate analysis, revealed that most fishermen who had started fly fishing since 2000 were under 40. Only few who were under 20 started to fish initially with the fly fishing equipment. They turned up committed to and skilled in fly fishing. Most of them live in large municipalities with much better economic opportunities. Their level of education is above average in Serbia. Economic power, place of residence and level of education outline their fishing capabilities, frequency of fishing outings, distance they travel to fly fish, as well as their attitudes towards fishery policy, conservation of native brown trout and grayling stocks, management of streams and communication with other fly fishermen. CODEN RIBAEG ISSN 1330-061X

Effects of the use of formic acid in different doses as the conserving in Lucerne ensiling

The influence of formic acid added in three doses (3,5 and 7 g/kg fresh mass) in the intensity of proteolysis and fermentation in Lucerne silages was investigated. On the basis of chemical analyses, it is observed that with the increase of conserving dose the lower pH value, limited proteolysis and increased preservation of proteins was achieved. The amino acid content varied very much due to their degradation and biosynthesis. In treated silages a statistically significant increase of lactic acid was observed while silages with maximum dose of conserving had significantly less free and total acetic acid. Presence of bonded butyric acid only in the control silage had no statistical significance. According to Dulphy and Demarquilly (1981) method, control silage with minimum dose of conserving was estimated as III class and silages with medium and high dose of formic acid were estimated as II quality class.

The influence of compression level and inoculation on biochemical changes in lucerne silages.

The effect of different levels of compression (A1 = 420 gdm-1, A2 = 560 gdm-1) and inoculation (B1 = no inoculant, B2 = with inoculant) on changes in chemical composition, proteolysis and quality of lucerne silage was investigated in this paper. Based on the results of chemical analysis we found that in silages with more compressed material there was a reduction in the amount of ammonia nitrogen, soluble nitrogen and acetic acid, and increased content of protein nitrogen (‘true’protein) and production of lactic acid (p<0.05). With the inoculation of the ensiling material the production of ammonia nitrogen and acetic acid was reduced but the content of lactic acid and acidity was increased (p<0.05). The interaction of both investigated factors (A×B) induced a decrease in the proteolysis degree, increase of lactic acid production and decrease in acetic acid production, and decrease in pH values (p<0.001) in investigated silages. The investigated factors had less influence on the chemical composition of lucerne material, and the significant variations were observed in fat and NFE contents. On the basis of this investigation the degree of compression is the most important parameter in ensiling technology. With the adequate compression and reduction of air in the starting material, the aerobic phase is reduced and the activity of proeolytic enzymes is decreased. In practice the special attention should be given to factors on which directly or indirectly the level of compression of ensiled material depends: wilting, cutting, object selection and/or selection of machines used for compression.

Influence of min-a-zel plus and maize meal addition on the quality of lucerne silage

The influence of mineral adsorbent Min-A-Zel Plus (5 g/kg) and maize meal (25 and 50 g/kg) used alone or combined, on chemical composition, biochemical changes and quality of lucerne silage was investigated. Based on the obtained data, it can be concluded that addition of Min-A-Zel Plus reduces aminogenesis, while the use of maize meal alone or with zeolite favorable conditions are achieved for lactic acid fermentation, so that the quality of obtained silages is better by one quality class. To achieve better effects of silage quality, the use of combination of mineral adsorbent with carbohydrate additives is recommended.

Yield and nutritional value of permanent grassland forage under simulated rotational grazing

A cutting experiment was conducted to test the changes in botanical composition, yield and nutritional value of forage, obtained in conditions of simulated rotational spring grazing on permanent grassland. The experiment was carried out on permanent pasture in vicinity of Šabac, Serbia in 2015 included three cuttings as a simulated rotational spring grazing. The highest share of grasses was noted in the first cut and decreased in the second and third cut, with increased forbs participation, and relatively constant percentage of legumes. The highest dry matter (DM) yield was obtained for the first harvest, followed by the second cut, and the lowest forage production was determined for the third harvest, with only 11.04 and 17.42% of the first and second cut yield. There were not found the significant differences between cuts for herbage DM and crude protein content. Markedly lower value for non-protein N concentration (p<0.05) was determined in the third cut. The fiber content increased during the grazing season (p<0.05), with the highest value determined in the herbage obtained in the second cut. The highest energy values (p<0.05) had the herbage produced in the first cut (DM basis), wherein the lowest values were found in the forage from the second harvest. These results indicate that especially herbage yield of analyzed grassland as chemical composition and nutrition value are highly variable during the growing season. The accurately defined optimal period for using is necessary to provide the high-quality forage for grazing animals.

Influence of addition of Zenural 70, urea and Min-A-Zel Plus on chemical composition and quality of whole maize plant silage

The influence of addition of Zenural 70, urea and Min-A-Zel Plus on chemical composition and quality of whole maize plant silage with different degree of compression was investigated in the paper. Experiment was two-factorial (2x3) with three replications, where factor A was a degree of compression (A, = 680 g/dm³; A2 = 550 g/dm³), while factor B was an additive type (Decontrol; B2=5 g/kg urea+2 g/kg Min-A-Zel Plus; B3=5 g/kg Zenural 70). Chemical analyses showed that with the addition of Zenural 70 and urea there was significant increase of pH value, total protein, mineral ammonia and soluble nitrogen content. The type of additive had no significant effect on production of lactic, acetic and butyric acid, while in silages with higher degree of compression (680 g/dm3) there was significantly more butyric acid. All silages were graded first class according to DLG and Flieg method, with the exception of lower compressed silage with added urea and Min-A-Zel Plus, which according to Flieg was second class. According to Zelter method, silages with added Zenural 70 were II and III class, while treatments with added urea and Min-A-Zel Plus were IV and V class.

The influence of inoculation on chemical composition and quality of silages made from soybean and entire maize plant

The ensiling of soybean and entire maize plant was done in experimental siloses with or without inoculant Sill-All (produced by Alltech inc). The experiment was organized as two-factorial (2 ´ 3, n = 3), where factor A was inoculant (a1 = without inoculant, a2 = with inoculant), and factor B was soybean and entire maize plant ratio (b1 = 1: 0; b2 = 2: 1 and b3 = 1 2). Inoculated silages at average had more lactic acid, lower pH values and higher content of ammonia nitrogen, nonsoluble nitrogen and NFE (P < 0.05). The included of entire maize plant in mixture produces high effect on reduction proteolysis. With the increase of entire maize plant share the decrease of pH values and amount of butyric acid, ammonia nitrogen, soluble nitrogen, crude protein and crude fiber was observed. According to the DLG method for silage quality evaluation, silages without inoculant had second class, and silages with inoculant had first class. Improvement in silage quality with the included entire maize plant from fourth to first class, was achieved.

The influence of mineral adsorbent „Minazel” on the reduction of residual zearalenone and its metabolites in cow's milk

The results of the use of mineral adsorbent - Minazel, a preparation based on natural zeolite, in the prevention of mycotoxicoses and avoidance of zearalenone and its metabolites transfer into cows milk were described in this paper. Using mineral adsorbent Minazel in a concentration of 0.5% of concentrate mixture the transfer of zearalenone from feeds to milk was prevented.