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The aim of this study was to investigate the influence of the biomanipulation on the living communities and water quality in the Strezhevo hydroecosystem, Republic of Macedonia in which a problem with increase of primary organic production has occurred. The biomanipulatory intervention in water bodies is used to prevent the development of macrophyte vegetation. It is achieved by direct influence on the increased development of phytoplanktonic production and macrophytes by gradual and controlled introduction of grass carp (Ctenopharyngodon idella). The study was conducted in the period June-September 2012 in two earthen ponds (A and B), situated in Strezhevo Lake with 100 specimens of grass carp/pond with average individual mass of 4 kg and age of 3–5 years. The following were monitored: water – temperature (oC), pH, dissolved oxygen (O2 mg/l) and saturation (%); grass carp – length (mm), weight (kg), Fulton and Clark coefficients of fattening, consumption of added in ponds fresh vegetable mass (kg), consisting of Ceratophyllum demersum (hornwort) (95%) and Potamogeton pusillus (small pondweed) (5%). Based on the results obtained, the meliorative ability of this species with high density of the stock was evaluated as very favourable. At optimal temperature, oxygen regime and pH conditions of water, this herbivore fish species consumed the present macrophytic vegetation very intensively, and in the case of its absence, also the additional share of fresh herbal mass, showing certain selectivity towards particular water vegetation species. Thus, grass carp maintains an optimal composition of the macrophytic communities in the hydroecosystem.

The objectives of this article were to determine the content of total dietary fibre (TDF) as well as of its fractions – soluble dietary fibre (SDF) and insoluble dietary fibre (IDF) of different cereals grown by conventional and organic farming in Macedonia, as well as to find out the influence of the cereal type and farming method on their values. Standardized enzymatic-gravimetric method (Megazyme Total Dietary Fiber Kit) was used for determination of soluble, insoluble, and total dietary fiber in 27 different cereal samples of wheat, rye, barley, oat, and millet, which were grown at three locations. The content of TDF, IDF and SDF was influenced by both cereal type and farming type. The organically grown cereals, primarily oat and barley, have shown higher values of TDF and of its fractions than the conventionally grown cereals. Their values (% db) for oat and barley for TDF were 42.00±1.39 and 21.91±2.01, for IDF 39.22±0.58 and 15.06±1.84 and for SDF 2.78±1.25 and 6.85±3.85, respectively. Barley grown by either organic or in conversion farming method proved to have the highest value of SDF content among the other cereals investigated, whereas oat produced by organic farming method exhibited the highest values of TDF and ISF content. The organic farming method proved to have a good perspective in cereal processing and technology, food market and nutrition.

Nutritional manipulation and genetic selection for egg size and production may lead to changes in egg components. This experiment was carried out to analyze the egg structure parameters of eggs produced by Hisex Brown laying hens fed with diet with different supplements inclusion. The intensity of egg production was significantly higher in the groups fed with enriched feed with iodine (90.00%), vitamin E (90.00%) and selenium (91.98%), and significantly lower in the group fed with DHA inclusion feed (76.00%) in respect to the control group (82.00%), confidence interval of 95%. Concerning diet supplemented with selenium and diet supplemented with vitamin E, the egg yolk weight was statistically different compared with the control group (confidence interval of 95%). The yolk weight averaged 1.80 g and 1.29 g more than yolk weight in the control eggs, respectively. The egg shell weight was statistically different in diet enriched with iodine compared with the control. The egg shell weight averaged 1.48 g less per egg for the eggs enriched with iodine with 17.45% less underweight than the control eggs. Enriched eggs offer consumer a variety of value-added options for their egg purchase. Although enriched eggs may provide consumers with a specific quality attribute or healthful ingredient, they do not appear to provide quality and value in a traditional sense as defined by the standards of quality and grade.

Traditional beaten cheese was manufactured in two different farms located in Mariovo region (southern Macedonia) during the summer period using raw ewe’s milk. High counts of all microbial groups were found in ewe’s milk (aerobic mesophilic bacteria 5.22x106-1.25x107 CFU•mL-1, presumptive lactococci 3.30x106-1.34x107 CFU•mL-1, presumptive lactobacilli 1.93x106-2.63x106 CFU•mL-1, coliform bacteria 2.35x105-6.30x105 CFU•mL-1 and yeasts 1.24x104-2.40x104 CFU•mL-1). The lactic acid bacteria prevailed during manufacturing and ripening of the ewe’s cheese. All investigated groups reached their maximum value during the dry ripening period and then gradually decline during salting and brining. A total of 240 isolates were taken from all stages of manufacturing and ripening. The prevailing species were Lactococcus lactis ssp. lactis (35 %), Pediococcus sp. (16.7 %), Leuconostoc sp. (1 %), Lactobacillus paracasei ssp. paracasei (22.5 %), L. plantarum (15.8 %) and L. brevis (9.17 %). After 45 days of ripening the content of NaCl (6.1±0.8 % and 6.6±0.1 %) and salt to moisture (S/M) ratio (15.6±1.4 % and 17.3±0.3 %) in both cheeses was very high. The values of pH were 5.13-5.22. The main factors influencing the microbiological counts were NaCl and S/M content, and a strong correlation (p

Soya isoflavones are compounds with phytoestrogenic character - istics, i.e. because of their structure, their effects are similar to those of animal estrogens. This is why they are used for medicinal purposes in aging women. The presented experiment with laying hens was conducted to demonstrate the possibility of transferring soya isoflavones from feed into egg yolk to produce isoflavone-enriched eggs. Laying hens were randomly assigned to a control and 3 experimental groups and fed a basal diet or the basal diet supplemented with different concentrations of isoflavones: 1000, 2000 or 3000 mg · kg -1 feed. The transfer of isoflavones (daidzein and genistein) from the feed into the egg yolk of treated hens was found to be significant. At the end of the experiment, the content of the analysed isoflavones was from 396.0 to 412.4 μg.

Isoflavones are phytoestrogens which have estrogen-like activity in animals and humans. Because of this characteristic influence, the aim of this investigation was to examine the effect of genistein and daidzein on testicular weight and testosterone secretion in ISA Brown roosters. Genistein and daidzein as non-steroid phytoestrogens were added in large amounts to the feed of roosters. Soy isoflavones were added to rooster diets in amounts of 0, 300, 600, 1200 and 1800 mg/kg of feed. At the end of the 37th week no significant differences were found between the groups in testicular weight (P>0.05) and testosterone secretion (P>0.05) measured in the blood of birds. Blood testosterone concentration was significantly higher in younger (20-week-old) roosters than in 37-weekold roosters (P