ISSN 1313 - 8820Volume 6, Number 1

March 2014

2014

Scope and policy of the journalAgricultural Science and Technology /AST/ – an International Scientific Journal of Agricultural and Technology Sciences is published in English in one volume of 4 issues per year, as a printed journal and in electronic form. The policy of the journal is to publish original papers, reviews and short communications covering the aspects of agriculture related with life sciences and modern technologies. It will offer opportunities to address the global needs relating to food and environment, health, exploit the technology to provide innovative products and sustainable development. Papers will be considered in aspects of both fundamental and applied science in the areas of Genetics and Breeding, Nutrition and Physiology, Production Systems, Agriculture and Environment and Product Quality and Safety. Other categories closely related to the above topics could be considered by the editors. The detailed information of the journal is available at the website. Proceedings of scientific meetings and conference reports will be considered for special issues.

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Editor-in-Chief

Tsanko YablanskiFaculty of AgricultureTrakia University, Stara ZagoraBulgaria

Co-Editor-in-Chief

Radoslav SlavovFaculty of AgricultureTrakia University, Stara ZagoraBulgaria

Editors and Sections

Genetics and Breeding

Atanas Atanasov (Bulgaria)Nikolay Tsenov (Bulgaria)Max Rothschild (USA)Ihsan Soysal (Turkey)Horia Grosu (Romania)Bojin Bojinov (Bulgaria)Stoicho Metodiev (Bulgaria)

Nutrition and Physiology

Nikolai Todorov (Bulgaria)Peter Surai (UK)Zervas Georgios (Greece)Ivan Varlyakov (Bulgaria)

Production Systems

Dimitar Pavlov (Bulgaria)Bogdan Szostak (Poland)Dimitar Panaiotov (Bulgaria)Banko Banev (Bulgaria)Georgy Zhelyazkov (Bulgaria)

Agriculture and Environment

Georgi Petkov (Bulgaria)Ramesh Kanwar (USA)Martin Banov (Bulgaria)

Product Quality and Safety

Marin Kabakchiev (Bulgaria)Stefan Denev (Bulgaria)Vasil Atanasov (Bulgaria)

English Editor

Yanka Ivanova (Bulgaria)

2014

ISSN 1313 - 8820 Volume 6, Number 1March 2014

Nutrition and Physiology

In vivo digestibility of cereal-based diets supplemented with sunflower vs. rapeseed meal

M. Yossifov*, L. Kozelov

Institute of Animal Science, 2232 Kostinbrod, Bulgaria

Abstract. Two experiments were conducted to investigate effects of rapeseed meal (RSM) vs. sunflower meal (SFM) as a protein source at cereal-based iso-nitrigenous (at 16 % CP), iso-caloric at gross energy 18 kcal/kg and net (FUG=1) energy diets for fattening lambs. Four wethers (Gygay breed) were used to evaluate the diets' apparent total tract digestibility (dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), crude fibres (CF), nitrogen free extractives (NFE) and ash) and coefficients (Cd) were used to calculate the diets' feeding value. Two diets were used: conrol diet (CD) with SFM and experimental diet (ED) with RSM. The results indicated that feeding RSM tended to increase Cd OM (p=0.1), Cd CP (p=0.4), Cd EE (p=0.5) and Cd NFE (p=0.1). The differences were significant at Cd DM (p<0.05), Cd CF (p<0.05) and Cd ash (p<0.001). According to the calculation analysis, diet supplementation with RSM benefits total digestible nutrients (TDN), raised energy values (gross energy, digestible energy and net energy) and improved protein feeding values (protein trully digestible in small intestines (PDI) and balance of protein in rumen (BPR)). Therefore, it's concluded that, substitution of SFM with RSM in cereal-based ruminant diets significantly (p<0.05) increased in vivo diet digestibility, raised (11 %) TDN and improved its energy and protein feeding value.

Keywords: sheep, digestibility, feeding value, rapeseed meal, sunflower meal

Abbreviations: SFM – sunflower meal, RSM – rapeseed meal, DM – dry matter, OM – organic matter, CP – crude protein, EE – ether extract, CF – crude fibres, NFE – nitrogen free exractives, Cd – coefficient of digestibility, CD – Conrol diet, ED – Experimental diet, TDN – total digestible nutrients, GE – gross energy, DE – digestible energy, NE – net energy, PDI – protein trully digestible in small intestines, BPR – balance of protein in rumen, FUM – feed units for milk, FUG – feed units for gain

AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 6, No 1, pp , 201421 - 23

Introduction of the Institute of Animal Science Kostinbrod, Bulgaria. Four wethers (Cygay breed, body weight=63±2 kg) were allocated to individual pens with free access to water, feed and salt blocks. The daily rations Nowadays, considerable emphasis has been placed on the

searching alternative vegetable-based protein supplements for animal diets. The goal might be rapeseed meal (RSM) because of widespread expansion of the fuel bioethanol industry. It has very good nutritional properties as feedstuff – rich in protein (30 – 40%) with high biological value (Newkirk et al., 2003) and fibres (10 – 24%). According to methods of oil extraction, residual oil content in rapeseed sub-products varied 2 – 15% (www.canolacouncil.org). Amino acid (AA) concentration, especially methionine, lysine and cystine (Wand, 2010) and fatty acid (FA), especially unsaturated FA (UFA) as C , C and C , are in charge of its productive effects. 18:1 18:2 18:3

Often RSM supplementation is limited by some anti-nutritional factors (ANF) – glucosinolates, uric acid, sinapine, tannins, etc., affecting the nutritional value and animal response (Bell, 1993). An ANF-s restricting maximum inclusion levels (Kramer et al., 1983) as followed: fattening 20%, lactating – 5–10% (www.countrywide.com; www.canolacouncil.org). So, some authors recommended optimal RSM inclusion levels less than 10% (Goopfert et al., 2006).

Based on our previous experiments (Yossifov and Kozelov, 2011) we aimed to substitute (42% on concentrate dry matter (DM) basis or 27% on diet DM basis) sunflower meal (SFM) and a part of cereal component (corn) with RSM, and to evaluate the effect on apparent diet nutrient in vivo digestibility and to establish the diet feeding value.

Material and methods

The experimental design was done in experimental base (EB)

21

* e-mail: m_vet@abv.bg

Table 1. Diet composition and nutritive value

TMR–Total mix ration, GЕ–Gross energy, FUG–Feed units per gain, СP–Crude protein, PDI–Protein truly digestible in small intestines, BPR– Balance of protein in rumen,Са–Calcium, Р–Phosphorus

Forages

Meadow haySunflower mealRapeseed mealCornTriticaleSupplement Limestone Dicalcium phosphate PremixTotal:

GE (kcal/kg)FUGСPPDIBPRСаР

RationsBPR/FUGCa/P

17.91.0

163.886.3

+ 26.512.15.2

+ 262.3

18.01.0

164.686.3

+ 25.212.05.3

+ 262.2

36.626.3

-17.217.22.72.40.10.2

100.0

36.3-

27.217.017.02.61.90.40.2

100.0

TMR (%)

In 1 кg DM

Control diet Experimental diet

22

(Table 1) were 63% concentrate mix with different protein source presented in Table 2. Protein sources (SFM and RSM) are relatively SFM for control diet (CD) and RSM for experimental diet (ED) plus high in CP (37 vs. 36 %, DM basis), which makes them juxtaposable. 36 % meadow hay. Both rations were equal in cereal components Results for apparent in vivo digestibility are shown in Table 3 as (34 %). Feeding values were calculated based on literature data. coefficient of digestibility (Cd). Based on these data the RSM Diets were iso-nitrogenous at 16% crude protein (CP), iso-caloric at treatment had possitive effect on nutrient digestibility. Digestibility of 18 kcal/kg gross energy (GE), net energy (NE) (1 FUG) and equal in DM from animals fed on the RSM-based diet (ED) was significantly Ca:P (2.2) and BPR:FUG (5.3) ratios. The chemical composition of higher than control (p<0.05). The organic matter (OM) (p=0.1), CP feeds was analyzed according to AOAC (2002). Total digestible (p=0.4), ether extract (EE) (p=0.5) and nitrogen free extractives NFE nutrients (TDN) were calculated according to NRC (2007), and (p=0.1) of ED showed only trends of higher digestibility. feeding value – www.noa.bg. Fiber digestion was significantly influenced by adding RSM

The wethers were offered concentrate mix (at 8.00 and 16.00 h) (p<0.05). The digestibility of the mineral component was also and hay (9.00 and 17.00 h) twice a day. Feces and urine excretion by significantly (p<0.01) improved with RSM replacement. The results each animal was recorded daily at 7.30 h over 7-d and subsampled are in good agreement with reports by Huhtanen (1998) and (10 %) for further analysis (Irungu et al., 1999). All parameters were Shingfield et al. (2003) that inclusion of different type protein analyzed using MS Office 2007 and Students' T-test. supplements had significant interactian and effects on apparent

digestibility. Moreover, Slominski (1994) explained higher diet digestibility with the better ratio of some oligosaccharides (raffinose, stachyose). The negative role of non-starch polysaccharides (NSP) Results and discussionmust be accounted.

Feeding values of diets are presented in Table 4. ED surpassed The composition and nutritive value of diet ingredients are

Table 2. Forages chemical composition, feeding value and macroelementary concentration

Cp–crude protein, EE-Ether extract, СF–Crude fibres, NFE– Nitrogen free extractives, GE–gross energy, FUG–feed units forgrowth, PDI–Protein digestible in small intestines, BPR–balance of protein in rumen.1 2 Our own data (Yossifov and Kozelov, 2011); Mg–60.0 mg, Fe–1.3, copper–1.0 mg, I–1.6 mg, Zn-60.0 mg, Co–1.0 mg,

3Vit.A–5000IU, Vit.D–2000 IU, Vit.E–10.0 mg; % DM

Forages

Meadow Hay1SFM1RSM

Corn

Triticale

Dicalcium

phosphate2Premix

84.74

86.32

87.35

81.66

83.57

88.00

88.00

8.47

37.24

36.35

7.38

12.04

-

-

1.09

0.82

3.07

2.71

1.44

-

-

35.78

20.84

13.70

3.17

3.72

-

-

48.86

33.60

39.59

85.70

80.95

-

-

5.80

7.50

7.29

1.04

1.85

-

-

1.82

1.94

1.95

1.80

1.8

-

-

0.06

0.08

0.09

0.18

0.18

-

-

6.40

17.08

16.62

0.92

9.05

-

-

- 1.72

13.62

12.81

- 5.24

2.88

-

-

0.33

0.44

0.70

0.06

0.06

23.20

-

0.16

1.21

1.03

0.21

0.35

18.00

-

DM, %

СP GЕ FUG PDI BPR Са РEE СF NFE Ash

3Chemical composition 1Feeding value 3Macroelements

Analyses

Table 3. Diets' digestibility (Cd)

* p<0.05; ** p<0.01

Experimental diet

Mean

Control diet

± SEM

SD

CV

Mean

± SEM

SD

CV

SEM

P-value

74.58*

1.94

3.88

5.20

83.17*

0.95

1.90

2.28

1.91

<0.05

76.93

1.88

3.77

4.90

83.25

2.07

4.15

4.98

1.76

<0.1

76.13

1.61

3.22

4.23

78.60

1.11

2.22

2.82

1.02

<0.4

60.31

3.62

7.24

12.00

67.66

9.04

18.08

26.72

4.72

>0.5

58.16*

4.01

8.02

13.79

75.69*

1.27

2.54

3.36

3.84

<0.05

83.63

1.24

2.48

2.97

89.42

0.77

1.55

1.73

1.29

<0.1

26.57**

2.29

4.57

17.21

56.00**

1.51

3.01

5.37

5.70

<0.005

AshNFEСFEEСPОMDMParameters

References

АOAC International, 2002. Official methods of analysis. 17th ed., Rev. AOAC Int., Gaithersburg, MD.Bell JM, 1993. Factors affecting the nutritional value of canola meal: A review. Canadian Journal of Animal Science, 73, 679-697.Goopfert E, Trekova M and Dvorak R, 2006. The use of treated rape cake in a starter diet. Chech Journal of Animal Science, 51, 491-501.Huhtanen P, 1998. Supply of nutrients and productive responses in dairy cows given diets based on restrictively fermented grass silage. Agricultural and Food Science in Finland, 7, 219-250.Irungu KG, Keingatti RK and Abate AN, 1999. Performance of beef steers fed brewers grain ensiled with hay or forage sorghum. Proceeding of 6th Biennial KARI Conference. Kenya Agricultural Research Institute,. Pp. 432- 439.Kramer JG, Sauer FD and Pigden WJ, 1983. High and Low Erucic CD in all observed parameters – TDN, GE, DE, net energy as FUG Acid Rapeseed Oil: Production, Usage, Chemistry, and Toxicology and FUM as follows: 18, 11, 1, 2, 2 and 2 %. So, the usage of RSM as Evaluation. Academic Press, NY.subsequent first lactation yield. vegetable protein source can be considered as a goal. Its chemical Cananadian Journal of Animal Science, 51, 681-686.composition, digestibility and feeding values offered it as high quality NRC – National Research Council, 2007. Nutrient Requirements protein supplement and alternative of SFM. Moreover, it surpassed of Small Ruminants: Sheep. Goats, Cervids, and New World SFM in all studied parameters.Camelids. National Academy Press, Washington, DC.Newkirk R, Classen H and Edney M, 2003. Effects of prepress-solvent extraction on the nutritional value of canola meal for broiler

Conclusion chickens. Animal Feed Science Technology, 104, 111-119.Shingfield KJ, Vanhatalo A and Huhtanen P, 2003. Comparison of

It can be concluded that, substitution of sunflower meal with heat-treated rapeseed expeller and solvent-extracted soya-bean rapeseed meal in cereal-based ruminant diets significantly (p<0.05) meal as protein supplements for dairy cow given grass silage-based increased in vivo diet digestibility, raised (11%) total digestible diets. Animal Science, 77, 305-317.nutrients and improved its energy and protein feeding value. Slominski BA, Campbell LD and Guenter W, 1994.

Carbohydrates and Dietary Fiber Components of Yellow- and Brown- Seeded Canola. Journal of Agrlculture and Food Chemistry,

Acknowledgements 1884, 704-707. www.canolacouncil.org, www.countrywide.com

This study was funded by the Agricultural Academy, Ministry of www.noa.bg/files/.../osnowi_na_hranenetoAgriculture and Food, Republic of Bulgaria, project 82. We thank the Wand С, 2010. Protein Content in Modern Sheep Rations, Beef personnel at the Department of Animal Nutrition and Feed Cattle, Sheep and Goat Nutritionist/OMAFRA, pdf.Technologies, Institute of Animal Science, Kostinbrod, particularly Yossifov M and Kozelov L, 2011. Еstimation of Rapeseed meal balance (Marieta Kupandolska) and laboratory (Galabena Borisova) (RSM) as protein source in small ruminant's diets. ISC, „250 years- staff in the research. Traditions and modernity in Veterinary Medicine", 24-25.11.11,

Sofia, Bulgaria, University of Forestry, Proceedings.

Table 4. Feeding value of diets

* Calculated with coefficients of digestibility (Cd) from Table 3* FUM-Feed units for milk

Components

TDN

GE

DE

FUG

FUM

(кg)

(%)

(kcal/kg)

1.3

68.0

18.0

12.2

1.33

1.16

1.1

61.5

17.9

12.0

1.31

1.14

Control diet Experimental diet

23

Review

Genetics and Breeding

Nutrition and Physiology

Production Systems

Blue-green coloured eggs in Gallus gallus domesticusH. Lukanov

Investigation on the resistance of doubled haploid sunflower lines to some biotic factorsM. Drumeva, P. Yankov, N. Nenova, P. Shindrova

Usage of cluster analysis for grouping hybrids and evaluation of experimental mutant maize hybridsM. Ilchovska, I. Ivanova

Biological fertility and milk yield in Bulgarian Dairy Synthetic Population sheep according to breeding lineN. Stancheva, I. Dimitrova, S. Georgieva

In vivo digestibility of cereal-based diets supplemented with sunflower vs. rapeseed mealM. Yossifov, L. Kozelov

Histometrical parameters in third eyelid (Harderian) gland of the common pheasant (Phasianus Colchicus Colchicus)D. Dimitrov

Studies on some cherry clonal rootstocks in nurseryG. Dobrevska

Parameters of "yield – irrigation depth" relationship for sunflower grown in the region of Plovdiv A. Matev, R. Petrova

Optimization of thickness of thermal insulation for roofs of turkey's housesR. Georgiev, V. Dimova, K. Peichev, Р. Georgiev

Sulfo technology for multiplication of sunflower hybrids resistant to tribenuron metil-based herbicidesC. Melucă, N. Pîrvu, T. Nistor, R. Sturzu, A. Stoilova

Influence of universal liquid fertilizer MaxGrow on yield and quality of durum wheat (Triticum durum Desf.) cultivar Progress G. Panayotova, A. Stoyanova

CONTENTS 1 / 2

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17

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24

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Effect of different types of main soil tillage on the vertical distribution of maize seeds in the soil layer and on the development of the plantsP. Yankov, M. Drumeva

Analysis of energy consumption for artificial lighting of rooms for fattening of pigsV. Katsarov, K. Peychev

Influence of Herbagreen mineral fertilizer on seed production of cucumber, melon and zucchiniN. Velkov, V. Petkova

Soil properties and salt content of soil from Inland salt meadow near Radnevo townM. Todorova, N. Grozeva, D. Dermendgieva

Botanical composition of the main pasture types in Sakar and Strandja regionV. Vateva, K. Stoeva, D. Pavlov

New data for Leucoagaricus and Leucocoprinus (Agaricaceae) in BulgariaM. Lacheva

Development and characteristics of accessions of Eragrostis tef (Zucc.) Trotter in the South DobrudjaH. Stoyanov

Possible adverse effects of tetracyclines on the human health and the environment

Y. Koleva, T. Dimova, G. Angelova

Contemporary assessment of the development of the genus Chaetoceros in the Bulgarian coastal watersD. Petrova, D. Gerdzhikov, G. Kostadinova

Ecological assessment of the phytoplankton community in the Bulgarian Black Sea coastal waters D. Petrova, G. Kostadinova, D. Gerdzhikov

Biopolymer matrix systems for incorporation of biologically active substancesS. Dyankova, A. Solak

Agriculture and Environment

Product Quality and Safety

CONTENTS 2 / 2

AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 6, No 1, 2014

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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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Volume 6, Number 1March 2014