Influence of Goji berries on oxidative changes, microbiological status and chemical properties of sausages

  1. Mitev1*, A. Kuzelov1, E. Joshevska2

1Department of Food Technology, Faculty of Agriculture, University „Goce Delchev”, 2400 Shtip, Republic of Macedonia

2Department of Food Technology, Faculty of Biotechnical sciences, University “St. Kliment Ohridski”, Bitola, Republic of Macedonia

(Manuscript received 11 January 2018; accepted for publication 28 February 2018)

Abstract. The objective of this study was to investigate the influence of dried and minced goji berries over the oxidative changes (acid level, peroxide value), microbiological status and chemical properties on semi-durable sausage vacuumed and kept at a temperature of +4°С. Therefore, four types of sausages were made. The study was carried out on the 1st, 10th, 25th, 35th, and 50th day of the production of the sausage groups. The acid level of all examined groups of sausages is increasing, and the highest increase is registered in the control group of sausages (2.08). During the storage of the sausages, the peroxide value increased from the first to the fiftieth day. The presence of Listeria monocitogenes, Salmonella, Escherichia coli, Staphylococcus aureus was examined as well as the number of aerobic bacteria. In all examined groups, none of the abovementioned bacteria were identified. During the storage of sausages, the number of aerobic bacteria ranged from 2.08 to 2.93 log/CFU/g, which was much lower than the permissible limit (7.00 log/CFU/g) according to the national legislation. The fruit of goji berry doesn’t have a significant effect on the chemical composition of the studied sausage groups.

Organoleptic properties of white yam (Dioscorea rotundata poir) as affected by autoclaving time

  1. Ahmed1*, Y.B. Kiri2, M.S. Abubakar3

1Department of Crop Science, Adamawa State University, Mubi, Adamawa State, Nigeria

2Department of Animal Production, Adamawa State University, Mubi, Adamawa State, Nigeria

3Department of Soil Science, Federal University Dutse, Jigawa State, Nigeria

(Manuscript received 22 October 2017; accepted for publication 31 January 2018)

Abstract. This experiment examined the effect of processing white yam (Dioscorea rotundata poir) using autoclave under different heating times with the main objective of assessing its effects on the organoleptic properties (colour, mealiness, taste, softness and wetness). Yam tubers were washed, peeled and chopped into chunks. Treatments consisted of yam autoclaved at the temperature of 121oC and pressure of 100 kPa using five different autoclaving times (0, 5, 10, 15 and 20 min) laid out in a Completely Randomized Design (CRD). Descriptive sensory analysis was conducted by five trained panelists using a 7-point descriptive scoring method. Data collected were subjected to Analysis of Variance using SAS (1999). Least Significant Differences (LSD) tests were used to compare means that showed significant difference at P≤0.05. The results show that, autoclaving time had positive influence on organoleptic properties of white yam. The effect was more apparent on yam autoclaved for 5 minutes and therefore, recommended to be adopted for improved sensory attributes of boiled white yam.

Residue analysis of difenoconazole in apple fruits grown in Republic of Macedonia

  1. Jankuloska1*, I. Karov2, G. Pavlovska1

1Faculty of Technology and Technical Sciences – Veles, “St. Kliment Ohridski” University – Bitola, Dimitar Vlahov 57, 1400 Veles, Republic of Macedonia

2 Faculty of Agriculture, University Goce Delchev, 2400 Shtip, Republic of Macedonia

(Manuscript received 18 July 2017; accepted for publication 11 November 2017)

Abstract. The purpose of this research was to determine the residue analysis of difenoconazole in apple fruits from Resen region, Republic of Macedonia. Analyzed were two varieties of apples, Golden Delicious and Idared. Samples were taken from two different locations in Resen in the year 2016. Difenoconazole analysis was performed with liquid chromatography-tandem mass spectrometry (LC-MS/MS) after a previous extraction of residue by applying the QuEChERS method. The obtained concentrations of residues of difenoconazole are compared with the maximum residue limit regulated by the Macedonian legislation. Analyses showed that the concentration of difenoconazole in both varieties of apples from two different locations is in the range of 0.01 to 0.41 mg/kg. In certain development phase of the apple fruits the concentration reaches 80 times lower concentration than the maximum limit. The data show that apple fruits can be safely consumed according to the recommended maximum residue limit (MRL) for difenoconazole in apples (0.8 mg/kg). Statistical processing of the data suggests that there is no significant difference between samples but presence of difenoconazole in apple fruits from both locations is with significant difference.

Influence of biomanipulation on the living communities and the water quality in the Strezhevo hydroecosystem, R. Macedonia

  1. R. Nastova*, V. Kostov, N. Gjorgovska, V. Levkov

Institute of Animal Science, “Ss Cyril and Methodius” University of Skopje, Bul. Ilinden 92a, 1000 Skopje, Republic of Macedonia

(Manuscript received 21 June 2017; accepted for publication 16 January 2018)

Abstract. 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.

Effect of nutmeg extract supplementation on some productive traits and economic efficiency of common carp (Cyprinus carpio L.) cultivated in recirculation system

  1. Zhelyazkov*, S. Stoyanova, I. Sirakov, K. Velichkova, Y. Staykov


Department of Biology and Aquaculture, Faculty of Agriculture, Trakia University,

6000 Stara Zagora, Bulgaria

(Manuscript received 21 December 2017; accepted for publication 16 February 2018)


Abstract. The aim of the present study was to evaluate the effect of a dietary nutmeg extract supplement on the survival rate, growth performance, feed conversion ratio and economic efficiency of common carp (Cyprinus carpio L.) reared in a recirculation system. Thirty-two carps were allotted into two experimental variants, each of them comprising two replications with 8 fish in a group. The average initial live weight of carps from the control group (CG) and experimental group (EG) was 866.56±113.99g and 868.50±111.18g, respectively (P>0.05). Fish were reared in concrete tanks with efficient volume of 0.8m3, elements of the recirculation system. They were fed pelleted carp feed with 25% crude protein produced by “Top mix” company, with pellet size of 6mm. The feed of fish from the EG was supplemented with 1% powdered nutmeg extract after lubricating the pellets with 5ml sunflower oil per 100g feed. Control carps received the same amount of sunflower oil-lubricated feed. The daily ration of fish from both replications was 1.8% of their live weight. The experiment duration was 45 days. The initial and final live weights were determined by individual weighing. By the end of the experiment, there was a tendency towards statistically insignificant higher average live weight in fish supplemented with 1% nutmeg extract – 986.44±125.91g vs 964.94±92.04g in non-supplemented controls (P>0.05). The survival rate of carps from both control and experimental group replications was 100%. The average individual weight gain of carps from the two EG replications (supplemented with 1% nutmeg extract) was 117.94±31.24g which was higher than that of controls by 16.58% but the differences were not statistically significant (P>0.05). At the end of the trial, the analysis of consumed feed amount showed that feed conversion ratio in the group supplemented with 1% nutmeg extract was 3.05±0.78, i.e. by 23.28% lower than that of control carps (P>0.05). The group that received 1% nutmeg extract exhibited better economic conversion ratio (2.71), by 4.06% lower than that of the non-supplemented group.

Economic efficiency of fattening on different genotypes slow-growing and fast-growing broiler chickens

  1. Oblakova*, Y. Popova, P. Hristakieva, N. Mincheva, M. Lalev


Agricultural Institute, 6000 Stara Zagora, Bulgaria

(Manuscript received 21 June 2017; accepted for publication 16 January 2018)


Abstract. In the present study six lines from the National Gene Pool (Bulgaria) were used, four of which – line NG (New Hampshire G), line E (Barred Plymouth Rock), line Ss (Sussex) and line F (NG x Red Rhode Island) as maternal forms in the crossing schedule and two sire lines, meat type – line L (White Plymouth Rock) and line M (Cornish), for production of slow-growing broilers. The effect of genotype on meat quality traits was studied with 5 groups of 150 unsexed day-old chicks from each genotype, and after the manifestation of sexual dimorphism – male and female chickens at 70 and 84 days of age. In valuation on revenues and costs of the fattening of the compared groups current prices at the time of the experiment were used. Cost of feed is determined according to the actual feed. In determining the economic efficiency of fattening, three variants of sales prices per kg of meat – 3.60 BGN/kg, 4.65 BGN/kg and 5.30 BGN/ kg have been analysed. The rate of profitability is a synthetic indicator for economic efficiency, calculated by the formula: NP = (Profitability / Production costs) * 100, %. Feed expenses for experimental group I were lowered by 22.8%, while in groups II, III, and IV- by 13.48%, 9.42% and 9.05%, respectively, compared to group V, which registered the highest consumption of feed in the amount of 5.52 BGN. The share of feed expenses in group I was 53.45% of total expenses, and in groups II, III, and IV group they were 59.88%, 56.30%, 57.50%, and 56.87%, respectively. The highest profits per the accepted sale prices were observed in group V- 10.71 BGN, 13.68 BGN and 15.52 BGN, respectively, followed by group IV with 8.56 BGN, 10.92 BGN, and 12.38 BGN, respectively.  At a level of sale prices of 3.60 BGN/kg a positive value of profitability was registered for the fattening of chickens from group V – 16.03%. In all other groups, the profitability norm was negative. At a level of sale prices of 4.65 BGN/kg, the highest profitability was observed in the chickens of group V – 48.21%, followed by group IV – 25.37%, while the lowest cost efficiency was in group III – 4.24%. In the variant with a sale price of 5.30 BGN/kg, the profitability norm was the highest in group V – 68.14%, followed by group IV – 42.13% and group II – 40.98%, while the lowest level was in group III – 18.21%.

Blood count in dogs with mammary gland carcinoma

Ts. Hristov*, R. Binev


Department of Internal Non-Infectious Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 26 June 2017; accepted for publication 21 January 2018)


Abstract. Haematological studies were conducted in 19 dogs (8 from small and 8 from medium-size breeds, 15 of which over 8 years of age) with mammary gland carcinoma at different stages of development. Blood samples were collected after a single venipucture of v. cephalica antebrachii in tubes with EDTA as anticoagulant. Complete blood count parameters: haemoglobin (g/L), haematocrit (%), erythrocytes (T/L), mean corpuscular volume (MCV, fL), mean corpuscular haemoglobin (MCH, pg), mean corpuscular haemoglobin concentration (MCHC, g/L), red cell distribution width (RDW, %), leukocytes (G/L), thrombocytes (G/L) were determined. Differential white blood cell counts were evaluated on blood smears stained with Hemacolor. The results showed anemia with erythropenia, without significant changes in erythrocyte indices, thrombocytopenia and leukocytosis, and slight variations in differential white blood cell count.

Slaughter traits of Pharaoh Japanese quails

А. Genchev1, H. Lukanov1*, I. Penchev2


1Department of Animal Science – monogastric and other animals, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

2Department of Morphology, Physiology and Nutrition, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria


(Manuscript received 29 November 2017; accepted for publication 23 January 2018)


Abstract. Slaughter traits and possibilities for production of manually deboned meat were investigated in Japanese quails. The study was conducted at the Poultry breeding unit of the Faculty of Agriculture, Trakia University – Stara Zagora. Slaughter yield and relative shares of the different cuts with bones and deboned breast and thigh meat were determined in 35-day-old Pharaoh Japanese quails. It was found out that the grill percentage (carcass without skin and giblets) was 58-64.5% of live weight. Breast with bone comprised 36.5-49.9% of grill weight, and thighs: 23.2-32.4%. From one quail, about 75.6-110 g deboned breast and thigh meat could be produced, e.g. 50-67% of grill weight. Breast meat yield was 47-72 g from one bird equal to 31.2-42.8% of grill weight. At 35 days of age, abdominal fat percentage was relatively low (0.8% of grill weight) with bird-to-bird variation of 0.12 and 2.1%. It could be concluded that Japanese quails are a promising species that could be marketed both as whole-body carcass (grill) or as manually deboned cuts (breast with bone and thighs). The ratio of deboned meat and bones plus remaining muscle tissue was 5.9 and 4.5 for breast and thighs, respectively.

Effect of dietary garlic powder and probiotics supplementation on growth performance of male classic broilers

  1. Lukanov1*, I. Pavlova2, A. Genchev1


1Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

2Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 6 December 2017; accepted for publication 24 January 2018)


Abstract. This study was conducted to evaluate the growth performance of male classic broiler chickens whose feed was supplemented with either garlic powder, probiotics or both. A total of 120 day-old male Ross 308 broiler chickens were divided into 4 groups: first group – control; second group: fed feed supplemented with Lactobacillus spp. probiotic combination; third group: fed feed supplemented with 0.4% garlic powder and fourth group: fed both 0.4% garlic powder and Lactobacillus spp. The experiment lasted until the 35th day of age. The results showed that the highest live weight at the end of the experiment was established in the group supplemented with probiotic+garlic powder (2257.51±3.87g), and the lowest – in the control group (2171.37±4.71g). The group supplemented with probiotic+garlic powder exhibited the highest average weekly weight gain during the 2nd, 3rd and 4th week of life and the highest total weight gain (2211.58±3.91g). The groups fed probiotic and probiotic+garlic powder had the most efficient feed conversion ratios (1.43±0.2). During the study period, there was no substantial decline in the consumption of feed containing 0.4% garlic powder. The supplementation of feed with garlic powder+Lactobacillus spp., had a beneficial effect on the growth performance of broiler chickens. Our data, in line with those of other research studies, suggested that the addition of 0.4% garlic powder combined with Lactobacillus spp. to poultry feed increased meat production in broiler chickens.

The effect of novel xylanase on feeding value of diet containing cereal by-products for broilers

J.M. Abdulla, S.P. Rose, V. Pirgozliev*


The National Institute of Poultry Husbandry, Harper Adams University, Shropshire, TF10 8NB, UK

(Manuscript received 23 November 2017; accepted for publication 31 January 2018)


Abstract. Effects of exogenous xylanase on N-corrected dietary apparent metabolisable energy (AMEn), coefficients of dry matter (DMR) and nitrogen retention (NR), fat digestibility (FD), and gastrointestinal tract (GIT) development were examined. Birds’ growth performance was also measured. Birds were fed one of two mash diets. A control diet was prepared that had major ingredients of 404.2 g/kg wheat and a mixture of important home produced cereal by-products (including 145.0 g/kg wheat DDGS, 90.0 g/kg oat feed, 60.3 g/kg wheat feed), and contained 213 g/kg CP and 12.64 MJ/kg metabolisable energy. Each diet was fed to sixteen pens with two Ross 308 male broilers following randomisation. Xylanase supplemented diet had higher (P<0.05) N-corrected apparent metabolisable energy (AMEn), and also higher (P<0.001) DMR and NR. There were no significant differences (P>0.05) in growth performance, although feeding xylanase decreased (P<0.05) the weights of the total GIT of the birds. It can be concluded that supplementary xylanase gave a small improvement (3.5% increase in AMEn) in the feeding value of the cereal by-product diet but this did not result in an improvement in growth performance.