ISSN (print) ISSN X (online) Volume 10, Number 1 March 2018

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1 ISSN (print) ISSN X (online) Volume 10, Number 1 March

2 Editor-in-Chief Georgi Petkov Faculty of Agriculture Trakia University, Stara Zagora Bulgaria Co-Editor-in-Chief Dimitar Panayotov Faculty of Agriculture Trakia University, Stara Zagora Bulgaria Editors and Sections Genetics and Breeding Atanas Atanasov (Bulgaria) Svetlana Georgieva (Bulgaria) Nikolay Tsenov (Bulgaria) Max Rothschild (USA) Ihsan Soysal (Turkey) Horia Grosu (Romania) Stoicho Metodiev (Bulgaria) Bojin Bojinov (Bulgaria) Nutrition and Physiology Nikolai Todorov (Bulgaria) Peter Surai (UK) Ivan Varlyakov (Bulgaria) George Zervas (Greece) Vasil Pirgozliev (UK) Production Systems Radoslav Slavov (Bulgaria) Dimitar Pavlov (Bulgaria) Jean-François Hocquette (France) Bogdan Szostak (Poland) Agriculture and Environment Martin Banov (Bulgaria) Peter Cornish (Australia) Vladislav Popov (Bulgaria) Tarek Moussa (Egypt) Product Quality and Safety Stefan Denev (Bulgaria) Vasil Atanasov (Bulgaria) Roumiana Tsenkova (Japan) English Editor Yanka Ivanova (Bulgaria) Scope and policy of the journal Agricultural 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. Submission of Manuscripts There are no submission / handling / publication charges. All manuscripts written in English should be submitted as MS-Word file attachments via to editoffice@agriscitech.eu. Manuscripts must be prepared strictly in accordance with the detailed instructions for authors at the website and the instructions on the last page of the journal. For each manuscript the signatures of all authors are needed confirming their consent to publish it and to nominate on author for correspondence. They have to be presented by a submission letter signed by all authors. The form of the submission letter is available upon from request from the Technical Assistance or could be downloaded from the website of the journal. Manuscripts submitted to this journal are considered if they have submitted only to it, they have not been published already, nor are they under consideration for publication in press elsewhere. All manuscripts are subject to editorial review and the editors reserve the right to improve style and return the paper for rewriting to the authors, if necessary. The editorial board reserves rights to reject manuscripts based on priorities and space availability in the journal. The journal is committed to respect high standards of ethics in the editing and reviewing process and malpractice statement. Commitments of authors related to authorship are also very important for a high standard of ethics and publishing. We follow closely the Committee on Publication Ethics (COPE), elines The articles appearing in this journal are indexed and abstracted in: DOI, EBSCO Publishing Inc., AGRIS (FAO) and DOAJ. The journal is accepted to be indexed with the support of a project BG051PO Science and business financed by Operational Programme Human Resources Development of EU. The title has been suggested to be included in SCOPUS (Elsevier) and Electronic Journals Submission Form (Thomson Reuters). The journal is freely available without charge to the user or his/her institution. Users can read, download, copy, distribute, print, search, or link to the full texts of the articles, or use them for any other lawful purpose, without asking prior permission from the publisher or the author. This issue is printed with the financial support by Contract No. DNP 06-41/ , financed from Fund 'Scientific Research' grant Bulgarian scientific periodicals. Address of Editorial office: Agricultural Science and Technology Faculty of Agriculture, Trakia University Student's campus, 6000 Stara Zagora Bulgaria Telephone: Technical Assistance: Nely Tsvetanova Telephone: editoffice@agriscitech.eu

3 ISSN (print) ISSN X (online) Volume 10, Number 1 March

4 AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 10, No 1, pp 34-36, 2018 DOI: /ast Nutrition and Physiology 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 g/kg wheat and a mixture of important home produced cereal byproducts (including g/kg wheat DDGS, 90.0 g/kg oat feed, 60.3 g/kg wheat feed), and contained 213 g/kg CP and 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. Keywords: cereal by-products, chickens, xylanase, metabolisable energy Introduction There is an increasing demand for the use of whole grain cereals in Europe. With the increased scarcity, the poultry industry may be required in the future to use an increasing amount of cereal by-products in their feed formulations. The by-product will not only be derived from human food production but also be sourced from bioethanol production. The increase of bioethanol production resulted in more available distillers dried grains with solubles (DDGS) for animal feed (Kanev et al., 2013; Pirgozliev et al., 2015). Traditionally fed to ruminants, this abundant and competitively priced co-product of bioethanol production can be also used in poultry diet formulations (Kanev et al., 2014, 2016). Most cereal byproducts have a high non-starch polysaccharides (NSP) content and so are the main reason for the reduced nutrient digestibility and growth performance of broilers (Ivanova et al., 2013; Whiting et al., 2016). Exogenous fibre degrading enzymes, e.g. xylanases, are now well accepted as a class of feed additives in diet formulations for poultry to overcome the negative effects of NSP, and to improve utilisation of dietary nutrients and birds performance. However, it is well recognised that bird's responses to xylanase addition are not entirely predictable and may depend upon the level of dietary substrate (Ravindran and Son, 2011). The objective of this experiment, therefore, was to determine the effect of supplementary novel xylanase, an enzyme that hydrolyses NSP, on dietary N-corrected metabolisable energy (AME), nutrient utilisation and gastrointestinal tract development when a high cereal by-product diet was fed to broilers. The overall feed intake, weight gain and feed conversion efficiency of the birds were also measured. Material and methods A control diet was prepared that had major ingredients of g/kg wheat and a mixture of important home produced cereal byproducts (including g/kg wheat DDGS, 90.0 g/kg oat feed, 60.3 g/kg wheat feed), and contained 213 g/kg CP and MJ/kg metabolisable energy (Table 1). The diet was then split into two batches and one of them was supplemented with xylanase (Kerry Ingredients and Flavours, Osberstown, Naas, Co. Kildare, Ireland) resulting in two diets in total. The determined activity of the enzyme was xylanase (EC ) 6100 units/kg diet (ESC Standard Analytical Method SAM036 at ph 5.3 and 50 C, using 1.2% BSA in the extraction; determined by Enzyme Services & Consultancy, Ystrad Mynach, UK), and there were some additional pectinase, amylase and α-galactosidase activities. The enzyme preparation was based on enzyme produced by Aspergillus niger. The enzyme was in a liquid form and was sprayed on the top of diet. The dry matter content of diet C was adjusted by spraying the same amount of water per kg of diet. After spraying the diets were thoroughly mixed in a horizontal mixer. Diets were free of coccidiostat, antimicrobial growth promoters, prophylactic and other similar additives. All procedures were approved by The Animal Experimental Committee of Harper Adams University. Male Ross 308 broiler chickens were obtained from a commercial hatchery. During the prestudy period, from day old to 7 days of age, the birds were reared in a single floor pen and fed proprietary wheat-based diet without coccidiostats or antimicrobial growth promoters, prophylactic or other similar additives. At the beginning of the study, at 7 days of age, 2 64 chicks were allocated to 32 small pens with m solid floors area, two birds in each pen, within a controlled environment room. * vpirgozliev@harper-adams.ac.uk 34

5 Table 1. Diet formulation (g/kg 'as-fed') of the diets Ingredient Wheat SBM (CP=48%) Full fat Soya meal Maize gluten meal Wheat DDGS Oat feed Wheat feed Soya oil Lysine Methionine Threonine Monocalcium phosphate Limestone Sodium chloride Vitamin/mineral premix Calculated composition ME, MJ/kg Protein, g/kg Soluble NSP, g/kg Insoluble NSP, g/kg Lysine, g/kg Methionine + Cysteine, g/kg Calcium, g/kg Available phosphorus, g/kg Sodium, g/kg Determined values (as fed) DM, g/kg GE, MJ/kg CP, g/kg Fat, g/kg Composition, % * Vitamin and mineral premix provided (units kg feed): μg: retinol 2160, cholecalciferol 75; mg: alpha-tocopherol 25, menadione 1.5, riboflavin 5, pantotenic acid 8, cyanocobalamin 0.01, pyridoxine 1.5, thiamine 1.5, folic acid 0.5, niacin 30, biotin 0.06, I 0.8, Cu 10, Fe 80, Se 0.3, Mn 80, Zn 80. Diets were not supplemented with coccidiostat Each diet was fed at random to 16 pens from 7 to 21d ages. Room temperature and lighting program followed commercial recommendations (Aviagen Ltd., Edinburgh, UK). Access to the feed and the water was ad libitum. During the last four days of the experiment, from 17 to 21 d age, the solid floor of each pen was replaced with a wire mesh and all excreta were collected and immediately dried at 60 C and then milled. Feed intakes were also measured for the same period. On the last day of the study, at 21d age, the two birds in each pen were weighed and killed by cervical dislocation. The empty weights of total gastrointestinal tract (GIT) including proventriculus and gizzard, pancreas and small intestine, of each bird were determined, according to the procedures described by Amerah and Ravindran (2008). Excreta were oven-dried in forced draft oven at 60 C to constant weight, weighed, and milled to pass through a 0.75 mm mesh. The gross energy, nitrogen and oil in feed and excreta were determined as previously described (Whiting et al., 2016). The dietary N-corrected apparent metabolisable energy (AMEn) was calculated as described by Hill and Anderson (1958). The coefficients of total tract fat dry matter (DMR) and nitrogen retention (NR), and fat digestibility (FD) were determined as the difference between the respective nutrient intake and nutrient excreted divided by the intake. Statistical analyses were performed using the Genstat statistical software package (Genstat 15th release 3.22 for Windows; IACR, Rothamstead, Hertfordshire, UK). All studied variables were compared statistically by ANOVA. In all instances, differences were reported as significant at P Tendencies towards significance (P<0.1) were also reported. Results and discussion All birds remain healthy throughout the study period and there was no mortality. There was no effect (P>0.05) of treatment on daily feed intake and weight gain of the birds (Table 2). However, bird fed xylanase supplemented diet tended (P=0.068) to have an improved feed efficiency when compared to the control fed birds. Birds fed xylanase had reduced total GIT weight (P<0.05) compared to the birds fed control diet. The study evaluated the efficacy of supplementary novel xylanase enzyme on growth performance, energy and nutrient availability and GIT development when cereal by-product containing diet was fed to broilers. The data demonstrate that young broilers are sensitive to dietary supplementation with exogenous xylanase. The most noticeable response to dietary enzyme preparation was in increasing DMR by 5.5%, followed by reducing total GIT by 4.8%, and increasing NR and AMEn by 4.4% and 3.5%, respectively. The growth of the birds did not differ between diets and was in the expected range for broilers reared in similar environment and fed mash diets (Karadas et al., 2014; Pirgozliev et al., 2015). In agreement with improved AMEn and nutrient utilisation, birds fed xylanase supplemented diet tended to improve FCE. This is in line Table 2. The effect of experimental diets on growth performance and total digestive tract (GIT) of broilers FI, g DM/b/d WG, g/b/d FCE, g:g Total GIT, g Control Xylanase SEM (df=31) P value CV, % Each mean represents values from 16 replicate pens of 2 chicks each; Bird performance was determined from 7 to 21 d age; There is statistically significant difference between treatments when P

6 Table 3. The effect of experimental diets on N-corrected apparent metabolisable energy (AMEn), dry matter (DMR), and nitrogen retention (NR), and fat digestibility (FD) Control Xylanase SEM (df=31) P value CV, % with Annison and Choct (1991), who reported reduced bird performance, dietary energy and nutrient availability when high NSP diets were fed to poultry. High dietary NSP content is also associated with high digesta viscosity (Annison and Choct, 1991). Dietary NSP, especially the water-soluble fraction has a significant capacity to attract and hold water and could directly interact with water molecules to form a large network or mesh-like structure, thereby increasing the viscosity of digesta. Although not determined, the increased digesta viscosity may be the reason for the reduced dietary energy and nutrient utilisation in birds fed unsupplemented control diet. The detrimental impact of high intestinal viscosity on dietary nutrient digestibility and absorption is well documented (Annison and Choct, 1991). The viscous properties have adverse effects on the diffusion and convective transport of pancreatic enzymes, substrates and the end products of the digestion process (Isaksson et al., 1982; Johnson et al., 1984). Xylanase is known to have the ability to degrade NSP in plants (Choct et al., 1999), thus supporting the assumption that reduction in digesta viscosity may explain the observed improvements in dietary energy and nutrient utilisation. After exogenous xylanase supplementation the weight of the GIT decreased by 4.8%, which is in the range of values reported by Wu et al. (2004), when feeding a mixture of phytase and xylanase to broilers. In general, if the efficiency of digestion is consistently suboptimal, whether due to ingredient quality, microbial interaction of anti-nutritive factors, the GIT responds by increasing in both size (surface area) and digestive enzyme output (Bedford 2006). 36 Conclusion The addition of a commercial xylanase enzyme preparation gave only a relatively small (3.5%) increase dietary available energy in the high cereal by-product diet and there was no evidence of an effect on growth performance of broiler chickens. Further research is warranted to understand how to efficiently include high levels of cereal by-products in broiler diets. References AMEn, MJ/kg DM DMR NR FD < Each mean represents values from 16 replicate pens of 2 chicks each; Dietary AMEn, DMR, NR and FD were determined between 17 and 21 d age; There is statistically significant difference between treatments when P Amerah AM and Ravindran V, Influence of method of wholewheat feeding on the performance, digestive tract development and carcass traits of broiler chickens. Animal Feed Science and Technology, 147, Annison G and Choct M, Anti-nutritive activities of cereal non-starch polysaccharides in broiler diets and strategies minimizing their effects. World's Poultry Science Journal, 47, Bedford MR, Effect of non-starch polysaccharidases on avian gastrointestinal function. In: Avian gut function in health and disease < (ed. GC. Perry). Carfax Publishing Company, Oxfordshire, UK, 28, Choct M, Enzymes for the feed industry: past, present and future. World's Poultry Science Journal, 62, Choct M, Hughes RJ and Bedford MR, Effects of a xylanase on individual bird variation, starch digestion throughout the intestine, and ileal and caecal volatile fatty acid production in chickens fed wheat. British Poultry Science, 40, Hill FW and Anderson DL, Comparison of metabolizable energy and productive energy determinations with growing chicks. Journal of Nutrition, 64, Isaksson G, Lundquist I and Ihse I, Effect of dietary fiber on pancreatic enzyme activity in vitro. Gastroenterology, 82, Ivanova I, Georgieva V and Lalev M, Effect of wheat dry distiller's grain in compound feeds for broiler chickens on productive and slaughter traits. Bulgarian Journal of Agricultural Science, 19, Johnson IT, Gee JM and Mahoney RR, Effect of dietary supplements of guar gum and cellulose on intestinal cell proliferation, enzyme levels and sugar transport in the rat. British Journal of Nutrition, 52, Kanev D, Nedeva R, Ivanova S and Szostak B, Effect of high levels dried distillers grains with solubles in performance of fattening pigs. Bulgarian Journal of Agricultural Science, 22, Kanev D, Palova N, Marchev Y and Ivanova-Peneva S, Influence of wheat dried distillers grains with solubles in feeding the suckling piglets from the East Balkan breed. Bulgarian Journal of Animal Husbandry, 6, (Bg). Kanev D, Palova N, Marchev Y, Ivanova-Peneva S and Nedeva R, Use of waste dried distillers grains with solubles in feeding the lactating sows from the East Balkan breed. Bulgarian Journal of Animal Husbandry, 1-2, (Bg). Karadas F, Pirgozliev V, Rose SP, Dimitrov D, Oduguwa O and Bravo D, Dietary essential oils improve the hepatic antioxidative status of broiler chickens. British Poultry Science, 55, Pirgozliev V, Karadas F, Rose SP, Beccaccia A, Mirza MW and Amerah AM, Dietary xylanase increases hepatic vitamin E concentration of chickens fed wheat based diet. Journal of Animals and Feed Sciences, 24, Ravindran V and Son JH, Feed Enzyme Technology: Present Status and Future Developments, Recent Patents on Food, Nutrition and Agriculture, 3, Wu YB, Ravindran V, Thomas DG, Birtles MJ and Hendriks WH, Influence of phytase and xylanase, individually or in combination, on performance, apparent metabolisable energy, digestive tract measurements and gut morphology in broilers fed wheat-based diets containing adequate level of phosphorus. British Poultry Science, 45,

7 AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 10, No 1, 2018 CONTENTS 1 / 2 Review Achievements and problems in the weed control in grain maize (Zea mays L.) G. Delchev, M. Georgiev 3 Genetics and Breeding Yield and coefficient of ecological valence of spring barley in the regions of Sadovo and Karnobat, Bulgaria N. Neykov, T. Mokreva Agronomic performance of mutant lines of winter two-rowed barley B. Dyulgerova, D. Valcheva, N. Dyulgerov Phenotypic diversity in six-rowed winter barley (Hordeum sativum L.) varieties N. Dyulgerov, B. Dyulgerova Evaluation of rye specimens in maturity stage on the base of mathematical statistical analysis V. Kuneva, E. Valchinova, A. Stoyanova Evaluation of lentil cultivars and lines for resistance to Fusarium oxysporum f.sp. lentis M. Koleva, Y. Stanoeva, I. Kiryakov, A. Ivanova, P. Chamurlyiski Registration of a new sunflower hybrid - Sevar P. Peevska, M. Drumeva, G. Georgiev Nutrition and Physiology The effect of novel xylanase on feeding value of diet containing cereal by-products for broilers J.M. Abdulla, S.P. Rose, V. Pirgozliev Effect of dietary garlic powder and probiotics supplementation on growth performance of male Ross 308 broilers H. Lukanov, I. Pavlova, A. Genchev Slaughter traits of Pharaoh Japanese quails А. Genchev, H. Lukanov, I. Penchev Blood count in dogs with mammary gland carcinoma Ts. Hristov, R. Binev Production Systems Economic efficiency of fattening on different genotypes slow-growing and fast-growing broiler chickens M. Oblakova, Y. Popova, P. Hristakieva, N. Mincheva, M. Lalev 48

8 AGRICULTURAL SCIENCE AND TECHNOLOGY, VOL. 10, No 1, 2018 CONTENTS 2 / 2 Effect of nutmeg extract supplementation on some productive traits and economic efficiency of common carp (Cyprinus carpio L.) cultivated in recirculation system G. Zhelyazkov, S. Stoyanova, I. Sirakov, K. Velichkova, Y. Staykov 54 Agriculture and Environment Influence of biomanipulation on the living communities and the water quality in the Strezhevo hydroecosystem, R. Macedonia R. Nastova, V. Kostov, N. Gjorgovska, V. Levkov 57 Product Quality and Safety Residue analysis of difenoconazole in apple fruits grown in Republic of Macedonia V. Jankuloska, I. Karov, G. Pavlovska Organoleptic properties of white yam (Dioscorea rotundata poir) as affected by autoclaving time M. Ahmed, Y.B. Kiri, M.S. Abubakar Influence of Goji berries on oxidative changes, microbiological status and chemical properties of sausages A. Mitev, A. Kuzelov, E. Joshevska

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Todorov N and Mitev J, Effect of level of feeding during dry period, and body condition score on reproductive perforth mance in dairy cows,ix International Conference on Production Diseases in Farm Animals, September 11 14, Berlin, Germany. Thesis: Hristova D, Investigation on genetic diversity in local sheep breeds using DNA markers. Thesis for PhD, Trakia University, Stara Zagora, Bulgaria, (Bg). The Editorial Board of the Journal is not responsible for incorrect quotes of reference sources and the relevant violations of copyrights. Animal welfare Studies performed on experimental animals should be carried out according to internationally recognized guidelines for animal welfare. That should be clearly described in the respective section Material and methods.

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