Online Version ISSN: 1314-412XVolume 5, Number 1

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2013

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Production Systems

Dimitar Pavlov (Bulgaria)Dimitar Panaiotov (Bulgaria)Banko Banev (Bulgaria)Georgy Zhelyazkov (Bulgaria)

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English Editor

Yanka Ivanova (Bulgaria)

Online Version ISSN: 1314-412X

2013

Volume 5, Number 1March 2013

Researching the resistance of bees fattened up with additive of extract of Tribulus terrestris L. during wintering

1 2 1I. Hristakov *, I. Zhelyazkova , V. Hvarchilkov

1Department of Agricultural Machinery, Agrarian and Industrial Faculty, University of Ruse Angel Kanchev, 8 Studetska, 7017 Ruse, Bulgaria2 Department of Animal Science – Non-ruminants and Other Animals, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

Abstract. In this paper the use of stimulated feeding by additive syrup extract of Tribulus terrestris is investigated. Three groups of bee colonies are included in the study (a control and two experimental), which are stimulated with inverted sugar solution and supplement of extract from Tribulus terrestris and the veterinary medical product “Startovit” during the autumn of 2010. It is established that the average percentage of hibernated bees in the control group of beehives is 72%. For the experimental group stimulated with supplement of extract from Tribulus terrestris, it is 76,53% and for the group fed with a supplement of “Startovit” - 75,56%.The average honey consumption by one interhold with bees for the whole winter period within the families from the control group is 1,37 kg, for those stimulated with extract it is 1,01 kg and those stimulated with “Startovit” have consumed an average of 1,25 kg of honey per interhold. The results show that bee colonies stimulated with extract of Tribulus terrestris have the best winter resistance compared to the control group and the group fed with “Startovit”.

Keywords: bees, extract of Tribulus terrestris, winter resistance

AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 5, No 1, pp 75 - 78, 2013

are formed in every living organism which in turn attack and kill body Introductioncells (Tsankov, 2007).

The purpose of this study is to determine the effect of adding an Timely and correct winterizing together with good wintering of extract from Tribulus terrestris L. to inverted sugar solution in autumn bees is of great importance for their normal development at the end on the resistance of bee colonies during the winter season (quality of of the winter and beginning of spring. Preparation of bee families for hibernated bees and honey consumption).gathering of honey and complete utilization of pasture depend on

this development. According to Bizhev (2005) winterizing of bees consists of: creation of necessary conditions; supplying enough and Material and methodsquality food; protection from wind, rain and snow; protection from

pests and peace. Based on the researches of Grancharov (2007), the bee family should include the so called “winter bees”. They differ The study was carried out in the autumn of 2010 and spring of from the summer bees by their anatomy-physiological signs. These 2011. The bee colonies (7 colonies in each group) are fed in autumn are bees fed with cumulated fat and protein tissue, heavily as follows:cumbersome, they should not have participated or been involved �Group 1, control – 200 ml inverted sugar solution for 3 days;with stern activities, should have not participated in processing �Group 2, experimental – 200 ml inverted sugar solution with sugar syrup – most of which are strongly cushioning activities that do additive of extract of Tribulus terrestris L. for 3 days;not support life. Their numbers should be in the area of 25 000 – 30 �Group 3, experimental – 200 ml inverted sugar solution with 000, in order to be able to reach the so-called “group effect”. A small additive of “Startovit” for 3 days.winter sphere is biologically ineffective against low temperatures. Inverted sugar solution (the compound sugars are inverted into Bees hatched in August and September have the wintering process, monosaccharides) is used. In this way, they are more easily because the later hatched ones cannot cumulate fat-protein acquired by bees without any risks of exhaustion. reserves. Sufficient stockpiling for bees is possible after a 27-day In group 1 dry plant extract of Tribulus terrestris L. is used period of nutritive feedings with no stern and sugar-processing manufactured by „VEMO-99” company, city of Sofia. This is original activities. Beekeepers quite often during autumn feed bee families non-hormonal product. For comparison in group 2 the veterinary with sugar syrup that does not contain biologically active medical product “Startovit” has been used witrh proven stimulating substances. If not inverted, it additionally exhausts bees and effect on the development of bee colonies. ”Startovit” contains: Natrii shortens their life expectancy. Beekeepers are facing the question of chloridum – 0,450 g, Cobalti chloridum – 0,0366; Dinatrii phosphas – how to prepare a more completed and easily assimilated sugar 0,010 and Excipiens ad 5,0 g. It is manufactured by “Primavet-Sofia” syrup for the bees. EOOD.

Usage of herbs and their healing effect is known from old times. Indicators which define the winter resistance of bee colonies Winslow and Kroll (1998) date back to the Neanderthal era the first have been determined:clues of using plants for healing purposes. Flavonoids are some of �Quality of hibernated bees (%). The count of dead bees P the active substances in the extract from Tribulus terrestris L. It has (bee death rate) can be calculated both in absolute numbers strong antioxidant influence as well as it blocks the free radicals that (interholds with bees) as well as in relative (%). The relative value of

75

* e-mail: ihristakov@ru.acad.bg

this indicator gives a more objective assessment and is calculated are 75,56% (from 71,43% to 81,82%) (Figure 1).with the following formula: The results show that dead bees during winter period in

colonies from the control group are 28%, in the group stimulated with plant extract – 23,5% and in the group fed with “Startovit” – 24,4%. According to Nenchev et al. (2002) a result below 20% for the family

where A is strength of the families in autumn, count of interholds is considered to be excellent and over 50% as weak performance.with bees, В is strength of the families in spring, count of interholds The recorded results show that stimulation of bee colonies in with bees. autumn supplemental feeding with plant extract of Tribulus terrestris

�Honey consumption (kg). The quantity of food invested for L. and with „Startovit“ has positive effect on the quantity of bees feeding during wintering is equal to the difference between the surviving through the winter period. More clearly expressed is the quantity of food during winterizing and during the informative review effect in bee colonies that had received plant extract with their feed. in spring. According to Nenchev et al. (2002), a measuring holder The definite higher percentage of bees surviving through the winter can be used by calculating the area filled with honey. In the in bee colonies fed with extract of Tribulus terrestris L. compared to calculation 1dm2 of honey sealed on both sides of the comb is equal the families in the control group and the group stimulated with to 350g. In standard practice (in our research, too), the quantity of „Startovit“ is an indicator for resistance of bees to the unfavourable sealed honey in the comb is calculated visually, it is multiplied for the winter conditions (winter resistance). As a result of the increased whole honeycomb and the result is converted in kilograms. winter resistance the number of worker bees in the bee nests is

�Honey consumption for one interhold (kg). If the strength of retained and at the beginning of the new beekeeping season they the family during autumn and spring is known, then we can easily will look after the brood and will provide the collection of nectar and calculate the invested food for one interhold of bees (M). That is why pollen from the early blossoming nectariferous plants. All that is of the total sum of food used during winter time (C) is divided by the crucial importance since it guarantees the normal development of average strength of the family in the winter season. The following bee colonies during the active period in their life.formula is used: The average honey consumption by a family in the control

group for the whole winter period is 5,29 kg, for the group fed with extract, it is 5,43 kg on average, and for the one with “Startovit” – 6,07 kg (Table 1). The data show that in the experimental groups At winterizing on 17.10.2010, the strengths in the hives for all stimulated with plant extract and with „Startovit“ the quantity of three groups have been measured in number of interholds consumed honey for the period 17.10. 2010 – 13.03. 2011 is greater occupied by bees, quantity of honey with which the colonies are than that of the control group. The provided values cannot be winterizing. A second measurement of the strengths (number of regarded as criterion for evaluating the winter resistance of bee interholds occupied by bees) and quantity of honey left was colonies due to the fact that there are differences in the strength conducted on 13.03.2011.(number of bees). Table 1 shows that at the onset of the winter season and during the spring check-up the strength of the colonies from the control group (fed with inverted sugar syrup only with no

Results and discussion additives) has low average values – 5,36 and 3,86 interholds with bees, respectively. The greatest is the number of bees in bee colonies from the group fed with extract of Tribulus terrestris – 7,00 The results of this study are indicated on Table 1. It is and 5,36 interholds. established that the average percentage of hibernated bees in the

With regard to this, an important indicator is the honey control group of beehives is 72% (from 66,67% to 80 %). For the consumption per one interhold with bees. The average honey experimental group stimulated with supplement of extract from consumption from one interhold with bees for the whole winter Tribulus terrestris L., it is 76,53% (from 71,43% to 81,25%) and for period within the families from the controlled group is 1,37 kg, for the group fed with a supplement of “Startovit”, the hibernated bees

Table 1. Wintering of bee cluster with the old bee mothers in 2011

Group

Group 1,

Control

5.50

5.00

5.00

5.00

6.00

5.00

6.00

5.36

5.00

6.00

14.00

14.50

13.00

15.00

14.00

13.50

14.50

14.07

13.00

15.00

4.00

3.50

3.50

4.00

4.00

3.50

4.50

3.86

3.50

4.50

9.00

9.50

8.00

9.00

8.50

8.50

9.00

8.79

8.00

9.50

1.25

1.43

1.43

1.50

1.38

1.43

1.22

1.37

5.00

5.00

5.00

6.00

5.50

5.00

5.50

5.29

1

2

3

4

5

6

7

Average values

Minimum values

Maximum values

72.73

70.00

70.00

80.00

66.67

70.00

75.00

72.00

Family №Strength

(interholds)Honey,

kgStrength

(interholds)Honey,

kg

Hibernatedbees (%)

Honeyconsumption

(kg)

Honeyconsumption(kg/interhold)

Winterizing17.10.2010

Spring inspection13.03.2011

76

P = .100A

A – B

M =0,5 (A + B)

C

kg

1.50

1.00

0.50

0.00Inspection Extract Startovit

Figure 2. Honey consumption per interhold

77

1

2

3

4

5

6

7

1

2

3

4

5

6

7

0.23

0.48

5.00

5.71

7.00

7.00

7.00

8.00

6.00

7.00

7.00

7.00

6.00

8.00

0.33

0.58

6.57

7.43

7.00

7.00

7.00

6.50

6.50

5.50

5.50

6.43

5.50

7.00

0.45

0.67

5.93

6.93

0.45

0.67

13.57

14.57

18.00

17.50

18.50

19.00

17.50

17.00

17.50

17.86

17.00

19.00

0.48

0.69

17.35

18.37

17.00

16.50

16.50

17.50

17.00

16.00

15.50

16.57

15.50

17.50

0.45

0.67

16.07

17.07

0.14

0.38

3.58

4.14

5.50

5.00

5.50

6.50

4.50

5.00

5.50

5.36

4.50

6.50

0.39

0.63

4.89

5.82

5.50

5.00

5.00

5.00

5.00

4.50

4.00

4.86

4.00

5.50

0.23

0.48

4.50

5.21

0.24

0.49

8.42

9.15

12.50

12.00

13.00

14.00

12.00

11.50

12.00

12.43

11.50

14.00

0.70

0.84

11.81

13.05

10.50

10.00

9.50

11.50

11.00

10.50

10.50

10.50

9.50

11.50

0.42

0.65

10.02

10.98

1.00

1.10

1.00

0.77

1.22

1.10

1.00

1.01

1.18

1.30

1.40

1.20

1.20

1.22

1.25

1.25

5.50

5.50

5.50

5.00

5.50

5.50

5.50

5.43

6.50

6.50

7.00

6.00

6.00

5.50

5.00

6.07

σ

Sx

Confidence

interval

Group 2,

Extract of Tribilus

terrestris L.

Average values

Minimum values

Maximum values

σ

Sx

Confidence

interval

Group 3,

“Startovit”

Average values

Minimum values

Maximum values

σ

Sx

Confidence

interval

78.57

71.43

78.57

81.25

75.00

71.43

78.57

76.53

78.57

71.43

71.43

76.92

76.92

81.82

72.73

75.56

Hibernated %

78.00

76.00

74.00

72.00

70.00

68.00Inspection Extract Startovit

Figure 1. Hibernated bees in %

78

those stimulated with extract it is 1,01 kg and those stimulated with Bee colonies stimulated with extract from Tribulus terrestris L. “Startovit” have consumed an average of 1,25 kg of honey per have a higher percentage of hibernated bees and consume less interhold (Table 1 and Figure 2). honey on an average bee interhold.

The results obtained show that feeding bee colonies with The plant extract of Tribulus terrestris L. can be applied in additive of plant extract of Tribulus terrestris L. and with the dosage of 10 mg/kg live weight of bees in combination with inverted veterinary medical product “Startovit” has positive effect on their sugar syrup to stimulate the development of bee colonies during the winterizing. The recorded stimulating effect in the application of autumn period and to improve their winterizing.“Startovit” during the autumn season confirms the positive effect of the product on the development of bee colonies proven in previous studies (Zhelyazkova et al., 2007).

ReferencesThe results from the comparative analysis among the groups of bee colonies included in the study make it possible to conclude that

Bizhev B, 2005. Upkeeping of bees. Sofia, Enyovche (Bg). colonies fed with extract of Tribulus terrestris spend the winter better Grancharov A, 2007. Why bees die. Beekeeping, 12, 2-5 (Bg).– they have a higher percentage of bees surviving through the winter Nenchev P, Kacarov G, Zhelyazkova I and Topalov A, 2002. and consume less honey on average per interhold with bees.Beekeeping, Dionis (Bg).Tsankov G, 2009. Bee bllom is rich in flavonoids. Beekeeping, 9, 19-20 (Bg).

Conclusions Winslow LC and Kroll DJ, 1998. Herbs as medicines. Arhive of Internal Medicine, 158, 2192-2199.

Bee colonies stimulated with extract of Tribulus terrestris have Zhelyazkova I, Gurgulova K and Popova V, 2007. Effect of the the best winter resistance compared to the control group and the veterinary medical product “Startovit” on the productive parameters group fed with “Startovit”. of bee colonies . Animal Science, XLIV, 4, 78-81 (Bg).

Review

Status of remote hybrids in the Poaceae: problems and prospectsH. Stoyanov*

Genetics and Breeding

Genetic divergence among accesions of coriander (Coriandrum sativum L.)N. Dyulgerov, B. Dyulgerova

Yield stability of contemporary Bulgarian winter wheat cultivars (Triticum aestivum L.) in DobrudzhaP. Chamurliyski, N. Tsenov

Assessment of initial material for stevia (Stevia rebaudiana B.) breedingTz. Kikindonov

Grain yield of winter feed barley varietiesB. Dyulgerova, D. Dimova, D. Valcheva, D. Vulchev, T. Popova, M. Gocheva

A study on the biological and economic qualities of common winter wheat (Triticum aestivum L.)I. Stankov, S. Tsvetanov, P. Stankova, I. Yanchev, T. Raycheva

Nutrition and Physiology

Drought–induced changes in photosynthesis of young cowpea plantsK. Uzunova, Z. Zlatev

Effect of organic fertilizers on photosynthesis of young tomato plants (Lycopersicon esculentum Mill.)Z. Zlatev, V. Popov

Production Systems

Productivity of sunflower grown in a periodic water deficit conditionsR. Petrova, A. Matev, H. Kirchev, A. Sevov

Variation of capillary rise of water in the slightly leached chernozem soil of Dobrudzha region under the effect of long-term use of some soil tillage practicesP. Yankov

Influence of the variety and sowing rate on the green mass productivity of Sudan grass and Sorghum x Sudan grass hybridsTz. Kikindonov, S. Enchev, K. Slanev

Effect of the irrigation regime on the productivity of root celery by drip irrigation in the Plovdiv regionB. Harizanova-Petrova, A. Ovcharova

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13

16

22

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Study of a zeolite–water experimental refrigeration module intended for animal raisingR. Georgiev, K. Peichev, A. Pavlov, K.Trendafilov, G. Dineva, I. Binev

Method for rapid determination of the percentage rate of grain losses by the combine harvester according to its parametersN. Delchev, K. Trendafilov

Phase–frequency characteristics of three types of milking clusters with a different volume and shape of the pulsation chamberB. Banev, K. Peychev, V. Vlashev, G. Dineva

Nondestructive (NIRS) determination of some technological traits of Bombyx mori L. cocoonsM. Panayotov, S. Atanassova, S. Petrova

Researching the resistance of bees fattened up with additive of extract of Tribulus terrestris L. during winteringI. Hristakov, I. Zhelyazkova, V. Hvarchilkov

Influence of liming with Ca(OH) on nitrogen, phosphorus and potassium content in foliage of vine 2

varietiesK. Trendafilov, V. Valcheva, S. Todorova

Content and composition of the essential oil of Rosa alba L. during flower developmentA. Dobreva, M. Gerdzhikova

Effectiveness of application of the leaf–fertilizers Hortigrow in sweet basil (Ocimum basilicum var. glabratum)V. Ivanov, I. Yanchev, T. Raycheva, K. Stoyanov

Agriculture and Environment

M. Lacheva

Agroclimatic conditions of existence of almond trees in Plovdiv region during the winter periodD. Ivanova, N. Shopova

Phytoplankton growth and chlorophyll – a content in the surface layer of the Bulgarian Black Sea coastal waters in 2011D. Petrova, D. Gerdzhikov

Ecological status of Varna Bay through the state of phytoplankton, macrozoobenthos and macrophytes during the autumn of 2011D. Petrova, E. Petrova, D. Gerdzhikov, V. Vachkova, R. Bekova

Environmental studies of the macrozoobenthos in the nearby coastal zone along the Bulgarian Black Sea coastE. Petrova, S. Stoykov

A study of macromycetes in Maglenishki Rid, Eastern Rhodopes Mts. II. Recent data of study

CONTENTS 2 / 3

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Reducing the hyperspectral feature spaces of ready-to-cook minced meat productsK. Kolev

Effect of cold storage terms on physico-chemical characteristics of Japanese quail (Coturnix coturnix japonica) meatS. Ribarski, A. Genchev, S. Atanasova

The flavonoid content in the white oil–bearing rose (Rosa alba L.)A Dobreva, M Gerdzhikova

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thmance in dairy cows,IX International Conference on Production Diseases in Farm Animals, Sept.11 – 14, Berlin, Germany, p. 302 (Abstr.).Thesis:Penkov D, 2008. Estimation of metabolic energy and true digestibility of amino acids of some feeds in experiments with muscus duck (Carina moshata, L). Thesis for DSc. Agrarian University, Plovdiv, 314 pp.

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