Prey size selectivity of pikeperch (Sander Lucioperca L.) fed with topmouth gudgeon (Pseudorasbora Parva Temminck & Schlegel)

M. Gevezova-Kazakova*, M. Yankova, T. Hubenova, A. Zaikov, G. Rusenov

Institute of Fisheries and Aquaculture, 4003, Plovdiv, Bulgaria
(Manuscript received 29 May 2017; accepted for publication 29 July 2017)

Abstract. The aim of this study is to examine the size selectivity of the pikeperch fed with one of the most widespread weed fish in fish farms, such as topmouth gudgeon (Pseudorasbora parva Temminck & Schlegel). Topmouth gudgeon (Pseudorasbora parva Temminck & Schlegel), separated in two size groups: large – group 1 (body weight of the specimens 8.63 ± 2.68 g, total length 9.58 ± 0.92 cm, and height of the body 2.06 ± 0.33 cm) and small – group 2 (body weight of the specimens 1.10 ± 0.36 g, average total body length of 5 ± 0.62 cm, and height of 0.85 ± 0.13 cm), were used for prey. The experiment was carried out under controlled laboratory conditions, in the course of 40 days, in 7 tanks. One pikeperch and 10 topmouth gudgeons from both size groups, in total 20 preys were placed in each tank. During the experimental period it was observed that pikeperch preferred to feed on smaller individuals, the difference in the number of consumed small and large fish is approximately 2 times (70 to 34, respectively).

Haematological and serum biochemical indices of broiler chickens fed raw sickle pod (Senna obtusifolia) seed meal

C. Augustine1*, I.D. Kwari2., J.U. Igwebuike2, S.B. Adamu2

1Department of Animal Production, Faculty of Agriculture, Adamawa State University, Mubi, Adamawa State, Nigeria 2Department of Animal Science, Faculty of Agriculture, University of Maiduguri, Borno State, Nigeria

(Manuscript received 12 April 2017; accepted for publication 20 June 2017)

Abstract. A feeding trial was conducted for sixty three (63) days (9 weeks) to evaluate the effects of feeding raw Senna obtusifolia seed meal (RSOSM) on haematological indices and serum biochemical parameters of broiler chickens. Six experimental diets were compounded for both the starter (23% crude protein – CP) and finisher (20% CP) phases of growth. The diets were formulated to contain 0, 5, 10, 15, 20 and 25% level of raw Senna obtusifolia seed meal replacing roasted soya bean weight for weight in T1, T2, T3, T4, T5 and T6, respectively. The 0% replacement level (T1) served as the control diet. The broiler chickens were managed on deep litter pens of 30 birds/2.22 m2, weighed and randomly allotted to the six (6) dietary treatments in a randomized complete block design (RCBD). Each treatment group consisted of thirty (30) broiler chicks replicated three times with ten (10) broiler chicks per replicate. Blood samples were collected from the wing vein at the end of the experiment using standard procedure and were analysed for haematological and biochemical profile. The outcome of this study revealed that the haematological indices were not significantly (P>0.05) affected by the dietary treatments. However, the blood chemistry was significantly (P<0.05) affected by the experimental diets. The total protein, albumin, globulin, and some electrolytes components were observed to be significantly (P<0.05) depressed as the level of RSOSM increased in the experimental diets. For instance, total protein was observed to reduce from 6.24g/dl in T1 to 3.6g/dl in T6. Electrolyte constituents such as calcium were similarly observed to reduce from 6.01 mmol/l in T1 to 1.15 mmol/l in T6. The serum enzymes and bilirubin were elevated as the level of RSOSM increases in the experimental diets. Aspartate amino transferase (AST) for instance increased from 8.27U/l in T1 to 23.18 U/l in T6. It can be concluded that incorporation of RSOSM beyond 5% in the diets of broiler chickens has adverse effects on blood parameters especially the biochemical parameters.

Variation in the chemical composition and physical characteristics of grain from winter barley varieties

B. Dyulgerova*, N. Dyulgerov, D. Dimova

Institute of Agriculture, 8400 Karnobat, Bulgaria
(Manuscript received 4 July 2017; accepted for publication 28 August 2017)

Abstract. The aim of the study was to evaluate the range of variation in chemical composition and in physical parameters of grain associated with feed quality of barley under the conditions of Southeast Bulgaria. A set of 21 winter six-rowed barley varieties from different geographic origins were investigated. The study was conducted in the Institute of Agriculture – Karnobat, during the period 2013/2014 – 2014/2015. Grain samples of the studied varieties were analysed for crude protein, lysine, starch, crude fat, crude ash, crude fiber, hectoliter weight and 1000 grains weight. The coefficient of variation was the highest in crude fat (21.52%) followed by lysine (9.52%). Low variation among varieties was found in nitrogen-free extract (CV=1.56%) and hectoliter weight (CV=2.77%). Correlations of crude protein with lysine, starch and crude fiber were negative. Starch content was positively associated with crude fat and hectoliter weight. Significant negative correlation of nitrogen-free extract with crude fat and crude fiber was found. Differences in chemical composition and physical parameters of grain indicated that the studied varieties can provide a source of germplasm for breeding winter barley varieties with improved feed quality.

In vitro propagation of oil-bearing rose (Rosa damascena Mill.)

V. Badzhelova*

Institute of Roses, Essential and Medical Cultures, Kazanlak, Bulgaria (Manuscript received 12 June 2017; accepted for publication 25 August 2017)

Abstract. The purpose of this research is to develop effective protocol for clonal micro propagation of the oil-bearing rose (Rosa damascena Mill.). Explants used in the experiment are 1.0 to 1.5 cm long nodal segments from specially cultivated mother plants. These explants were subjected to a combined method of sterilization with 0.2% solution of HgCI2 for 3 minutes followed by 0.50% solution of NaClO for 20 minutes and 0.25% solution of NaClO for 30 minutes. The best results of multiplication were obtained in basic MS medium with added BAP quantity of 0.5 to 3.0 mg/L. After being separated from the mother plants the young shoots are placed directly in compost mixture for rooting and adaptation. Thus the process of multiplication is shortened, avoiding the period of in vitro rooting.

Parthenogenetic responsiveness of sunflower hybrid combinations with expressed tolerance to herbicides

M. Drumeva*, P. Yankov

Department of Plant Production, Faculty of Shipbuilding, Technical University Varna, 1 Studentska, 9010 Varna, Bulgaria (Manuscript received 6 March 2017; accepted for publication 3 July 2017)

Abstract. For accelerated development of fertility restorer lines with imidazolinone tolerance in sunflower (Helianthus annuus L.), the gamma-induced parthenogenesis, which combines classical breeding approaches and in vitro techniques, was applied. As initial materials six imidazolinone-tolerant hybrid combinations (F1203, F1216, F1246, F1248, F1295 and F1332), obtained from Dobrudzha Agricultural Institute, General Toshevo, were used. To initiate parthenogenetic development mixed pollen from different fertility restorer lines was applied. The mixed pollen was irradiated with a dose of 600 Gy. A total of 166 parthenogenetic immature embryos were obtained, and 84 young plants developed from them, 42 of the plants were fertile. Best parthenogenetic response, expressed as a number of embryos obtained, was observed by hybrid combination F1295, followed by hybrid combination F1332. The lowest parthenogenetic responsiveness is reported in hybrid combinations F1246 and F1248, where the total number of parthenogenetic embryos obtained was 5. In hybrid combinations F1295 and F1332, as well as in F1216, the method of gamma-induced parthenogenesis can be efficiently used for accelerated production of parental lines for heterosis breeding in sunflower. In hybrid combinations F1203, F1246 and F1248, which showed low parthenogenetic responsiveness, conventional methods for developing lines from these hybrids are recommended.

Achievements and problems in the weed control in grain sorghum (Sorghum Bicolor Moench.)

Gr. Delchev*, M. Georgiev

1Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria (Manuscript received 28 November 2016; accepted for publication 21 March 2017)

Abstract. Chemical control has emerged as the most efficient method of weed control. Herbicides combinations and tank mixtures of herbicides with adjuvants, fertilizers, growth regulators, fungicides, insecticides are more effective than when applied alone on sorghum crops. Their combined use often leads to high synergistic effect on yield. The use of herbicide antidotes for the treatment of seeds in sorghum is a safe way to overcome its high sensitivity to many herbicides. Data regarding herbicide for chemical control of annual graminaceous weeds in sorghum crops are quite scarce even worldwide. Problem is the persistence of some herbicides used in the predecessors on succeeding crops, which is directly related to the weather conditions during their degradation. Most of the information on sorghum relates to the conventional technology for weed control. There is no information about the new Concep technology in grain sorghum. A serious problem is also the volunteers of the Clearfield and Express sun sunflower. They have resistance to herbicides different from that of conventional sunflower hybrids. There is no information yet in scientific literature on control of these volunteers.

Problems and achievements of cotton (Gossypium Hirsutum L.) weeds control

T. Barakova1*, G. Delchev2
1Field Crops Institute, 6200 Chirpan, Bulgaria
2Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria
(Manuscript received 2 June 2017; accepted for publication 17 August 2017) Abstract. Weed control in the cultivation of cotton is critical to the yield and quality of production. The influence of economically important weeds was studied. Chemical control is the most effective method of weed control in cotton but much of the information on it relates to primary weed infestation. Problems with primary weed infestation in cotton have been solved to a significant extent. The question of secondary weed infestation with annual and perennial graminaceous weeds during the period of cotton vegetation is also determined largely by the use of antigraminaceous herbicides. The data related to herbicides to effectively control secondary germinated broadleaf weeds in conventional technology for cotton growing are quite scarce, even globally. We are still seeking effective herbicides for control of these weeds in cotton crops. Studies on their influence on the sowing characteristics of cotton seed and the quality of cotton fiber are still insufficient. In the scientific literature there is not enough information on these questions. The combinations of herbicides, as well as their tank mixtures with fertilizers or plant growth regulators are more efficient than autonomous application. Often during their combined application higher synergistic effect on yield is produced. There is information about cotton cultivars resistant to glyphosate. These cultivars are GMO and they are banned within the European Union, including Bulgaria.

Volume 9, Number 3, September 2017

Reviews

Problems and achievements of cotton (Gossypium Hirsutum L.) weeds control
T. Barakova, G. Delchev

Achievements and problems in the weed control in grain sorghum (Sorghum Bicolor Moench.)
G. Delchev, M. Georgiev

Genetics and Breeding

Parthenogenetic responsiveness of sunflower hybrid combinations with expressed tolerance to herbicides
M. Drumeva, P. Yankov

In vitro propagation of oil-bearing rose (Rosa damascena Mill.)
V. Badzhelova

Nutrition and Physiology

Variation in the chemical composition and physical characteristics of grain from winter barley varieties
B. Dyulgerova, N. Dyulgerov, D. Dimova

Haematological and serum biochemical indices of broiler chickens fed raw sickle pod (Senna obtusifolia) seed meal
C. Augustine, I.D. Kwari, J.U. Igwebuike, S.B. Adamu

Prey size selectivity of pikeperch (Sander Lucioperca L.) fed with topmouth gudgeon (Pseudorasbora Parva Temminck & Schlegel)
M. Gevezova-Kazakova, M. Yankova, T. Hubenova, A. Zaikov, G. Rusenov

Influence of organic nitrogen amendment, containing amino acids on the cellulase and xylanase, produced by Trichoderma spp. isolates
D. Draganova, I. Valcheva, Y. Kuzmanova, M. Naydenov

Production Systems

Justification of a method for determining the moment for switching on the level one signaling of filled grain harvester hoppers
G. Tihanov, B. Kolev, K. Trendafilov, N. Delchev, Y. Stoyanov

Mathematical approaches for assessment and classification of the European Union member states based on the average yield of vegetables for the period 1961-2014
N. Keranova

Present status of Zymoseptoria tritici (Mycospharella graminicola /Fuckel/ Schroter) of the wheat cultures in the Republic of Macedonia
I. Karov, E. Arsov

Agriculture and Environment

Influence of basic agrotechnical activities on the productivity and yield of Triticum monococcum L.
S. Stamatov, K. Uzundzhalieva, E. Valchinova, G. Desheva, P. Chavdarov, B. Kyosev, T. Cholakov, R. Ruseva, N. Velcheva

Avifauna abundance and diversity in Jos wildlife park, Nigeria
B.T. Kwaga, D. Iliya, A. Ali, D. Khobe

Ecological analysis of the flora in the ‘Chinarite’ protected area – Rodopi municipality, Bulgaria
L. Dospatliev, M. Lacheva

Product Quality and Safety

Food emulsions with amidated pectin from celery (Apium graveolens var. rapaceum D. C.) tubers
Iv. Petrova, N. Petkova, M. Ognyanov, Ap. Simitchiev, M. Todorova, P. Denev

Sensory and instrumental texture analysis of Bulgarian commercial pates
M. Tonchev, T. Atanasov, A. Todorova, Ts. Atanasova, N. Shtrankova, M. Momchilova G. Zsivanovits

Short Communication

Influence of elevated platform (wire-mesh or wooden) in the cage on domestic rabbit (Oryctolagus cuniculus) activity
S. Peeva, E. Raichev, D. Georgiev, A. Stefanov

Carcass characteristics and technological properties of Musculus Longissimus Lumborum at lambs from the Bulgarian dairy synthetic population and its F1 crosses with meat breeds

N. Ivanov1*, T. Angelova1, S. Laleva1, S. Ribarski2, D. Miteva1, D. Yordanova1, V. Karabashev1, I. Penchev2

1Agricultural Institute, 6000 Stara Zagora, Bulgaria
2Department of Morphology, Physiology and Nutrition, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 28 March 2017; accepted for publication 26 May 2017)

Abstract. The purpose of this study is to determine the effects of the breed on some of the carcass characteristics and the technological properties of Musculus Longissimus Lumborum in lambs from the Bulgarian Dairy Synthetic Population and its F1 crosses with Ile de France and Mutton Charollais breeds. The scientific study took place at the Agricultural Institute of Stara Zagora, Bulgaria. Object of the study were lambs from the Bulgarian Dairy Synthetic Population and its crosses with Ile de France and Mutton Charollais breeds. The internal organs weight of the animals from the three groups was measured after their slaughter. In order to determine the meat/bones ratio, the left carcass halves were deboned. The eye muscle area and analyzed samples of Musculus Longissimus Lumborum was determined. The results show a slight variation in the weight of the internal organs of the animals from the three groups. The Mutton Charollais crosses come first in terms of eye muscle area (11.34 cm2), followed by the Ile de France crosses (11.21 cm2), and the lambs from the reference group come last with only 8.64 cm2 (P ≤ 0.001). With regard to the meat/bones ratio, it was found out that in the Ile de France crosses it is the highest (2.90:1), followed by the Mutton Charollais crosses (2.68:1), and the lambs from the reference group (2.43:1) where it is the lowest (P >0.05). Ile de France crosses exhibited statistically significantly higher meat tenderness (P ≤ 0.001) and water-holding capacity (WHC) (P ≤ 0.01), while Mutton Charollais crosses – considerably higher cooking losses (P ≤ 0.001) than control animals.

Exopolysaccharide influence on acid gel formation

K. Yoanidu1, P. Boyanova2*, P. Panayotov2

1Department Industrial Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 26 Acad. G. Bonchev, 1113 Sofia,
Bulgaria

2Department of milk and milk products, Faculty of Technology, University of Food Technologies, 26 Maritza, 4000 Plovdiv, Bulgaria

(Manuscript received 12 February 2017; accepted for publication 16 April 2017)

Abstract. Turbidimetric monitoring of milk coagulation was conducted in situ. Milk gel was produced by acidification with the use of three strains of starter culture. These strains were characterized by various acidification rate and exopolysaccharides (EPS) production. The concentrations of EPS affect mostly the pH of gel formation (5.53 – low EPS – producing strain; 5.33 – medium EPS – producing strain; 5.46 – high EPS – producing strain) whereas the time of gel formation depends on the various rate of acidification of all three strains.