80 Acta argiculturae Slovenica, Supplement 5, 80–83, Ljubljana 2016 24th Int. Symp. “Animal Science Days”, Ptuj, Slovenia, Sept. 21st−23rd, 2016. COBISS: 1.08 Agris category code: L02 EFFECT OF FEEDING SUPPLEMENTAL EXOGENOUS AMYLASE ON THE PERFORMANCE OF HIGH YIELDING DAIRY COWS Tamás TÓTH 1, Róbert TÓTHI 2 Effect of feeding supplemental exogenous amylase on the performance of high yielding dairy cows 1 Kaposvár University, Faculty of Agricultural and Environmental Sciences, Institute of Nutrition and Product Development, Department of Animal Nutrition, P.O. Box 16, H-7401 Kaposvár, Hungary, e-mail: toth.tamas@ke.hu 2 Same address as 1, e-mail: tothi.robert@ke.hu ABSTRACT The objective of this study was to determine the effect of an exogenous rumen-resistant amylase preparation on live weight, milk production and milk composition in Holstein Friesian dairy cows (n = 70) in a dairy farm experiment. According to the Hungarian feeding practice corn silage-alfalfa haylage-dried corn meal based diet was used in the diets. Milk production was recorded every day. Chemical analyses were made from the morning milked samples once a week. There was a 3-week long preliminary and a 12-week long experimental period in the trial. Cows used in the experiment were in the 71st (control) and 72nd (experimental) day of lactation. All the animals were weighed at the beginning (con- trol: 651 kg/cow; experimental: 657 kg/cow) and at the end of the trial (control: 685 kg/cow; experimental: 697 kg/cow). The exogenous rumen-resistant α-amylase used in this trial significantly (p < 0.05) improved milk production (control: 37.7 ± 6.96 kg vs. experimental: 38.7 ± 6.97 kg) and significantly (p < 0.001) decreased lactose content of milk (4.60 % vs. 4.55 %). The exogenous rumen-resistant α-amylase had no influence on the fatty acid composition of milk fat. Key words: cattle, dairy cows, animal nutrition, exogenous α-amylase, milk production, milk composition 1 INTRODUCTION Dairy cows producing 30 to 50 kg milk per day re- quire approximately 2.5 to 4.0 kg glucose daily, but only a small amount (0.5 to 1.0 kg/day) of glucose is absorbed in the small intestine (Flachowsky and Lebzien, 1997). Blood plasma and liver glucose pool in the cow limited to 520 to 550 g, thus 1.0 to 3.0 kg glucose has to be synthe- sized through the gluconeogenesis pathway for the milk production mentioned. Besides improving gluconeo- genesis, increasing the grain content of the diet is often used in practice. However, rapid digestion of excessive amounts of starch in the rumen can result in ruminal acidosis and reduce dry-matter intake and production (Owens et al., 1998). Thus, while it may be desirable to achieve high levels of starch digestion in the rumen, avoiding ruminal fermentation conditions that lead to acidosis is also important. For these reasons the pressure is growing to reduce starch in dairy cow rations, making optimization of starch digestibility an important area of research (Nozière et al., 2014). Feed enzymes are a radical innovation in dairy cow nutrition. Several studies have demonstrated that exogenous α-amylase preparations re- sistant to ruminal degradation are able to improve OM digestibility (Hristov et al., 2008; Gencoglu et al., 2010) and providing better milk efficiency by optimizing starch utilization in the rumen of dairy cows. Amylase can help to hydrolyse slowly fermentable corn starch shifting the digestion more towards the rumen. This provides more energy for microbial growth of cellulose degrading bac- teria and thus increases fibre digestibility in the rumen. This characteristic especially alleviates the energy gap in the first 150 days of lactation (Weiss et al., 2011). There- fore the objective of the present work was to evaluate the effect of an exogenous α-amylase preparation on live weight, milk production and milk composition in dairy Acta agriculturae Slovenica, Supplement 5 – 2016 81 EFFECT OF FEEDING SUPPLEMENTAL EXOGENOUS AMYLASE ON THE PERFORMANCE OF HIGH YIELDING DAIRY COWS cows. Increased dietary starch concentration decrease the apparent transfer of dietary polyunsaturated fatty ac- ids to milk, suggesting an increased channeling of fatty acids to adipose tissue (Cabrita et al., 2007). Addition- ally, dietary effects on milk fatty acid profiles were also investigated. 2 MATERIAL AND METHODS 2.1 COWS, FEEDS AND MANAGEMENT Trials were established at the commercial dairy farm of Solum Co. in Komárom (Hungary). In a randomized complete block design multiparous Holstein Friesian dairy cows were used either in the control (n = 35) and experimental (n = 35) groups which were in the second and third lactation (DIM: 71 days control and 72 days ex- perimental). Average daily milk yield 3 weeks prior to ex- perimental period was 42.9 ± 7.0 kg/day for the control; 42.8 ± 6.8 kg/day for the experimental group. Cows were given a corn silage-alfalfa haylage-dried corn meal based diet (Table 1 and Table 2). An exogenous α-amylase preparation (Ronozyme® Rumistar, DSM) was given to the cows in the experimental group daily. Supplement was added to concentrate (12 g/cow/day). Diets were of- fered ad libitum as total mixed diets twice daily at 11.00 and 17.00 h. There was a three-week preliminary feeding period prior to milk production experiment which was lasted 12 weeks. Cows were accustomed to the feeding of enzyme preparation during preliminary feeding period. Cows were milked twice daily and individual milk yields were recorded at each milking. Milk composition was de- termined on consecutive morning and evening samples collected once weekly. Cows were weighed at the begin- ning and at the end of the experiment after the morning milking. 2.2 CHEMICAL ANALYSIS The composition of milk was analyzed by the Hun- garian Dairy Research Institute (Mosonmagyaróvár, Hungary), where the fat, protein, lactose and dry matter contents of the milk were measured. Milkoscan FT 120 (Foss Electric) equipment was used for the analysis. The chemical content of the feeds were analyzed according to the Hungarian Feed Codex (2004). Starch content of feed was measured with a polarimeter (Carl Zeiss, Jena, Ger- many) as described in the Hungarian Feed Codex (2004). Fatty acid profile of the feed and milk samples were deter- mined using Agilent Technologies 6890N (Agilent Tech- nologies, Foster City, CA, USA) gas chromatography ac- Item Control Amylase Ingredient composition, % of DM Corn silage 31.8 31.8 Alfalfa haylage 13.3 13.3 Grass hay 8.2 8.2 Dry corn meal 19.6 19.6 Sunflower meal 7.6 7.6 Soybean meal 4.5 4.5 Rapeseed meal 5.2 5.2 Molasses 3.6 3.6 Concentrate * 2.5 2.5 Amylase (g/cow/d) ** 0.0 12.0 Chemical composition, g/kg of DM CP 173 175 NDF 342 335 ADF 197 199 ADL 43 45 EE 42 40 NFC 372 379 Starch 260 260 Sugar 95 100 Table 1: Ingredients and chemical composition of the diets * produced by Vitafort Co. (Dabas, Hungary) ** distributed by DSM Hungary Ltd. (Újhartyán, Hungary) cording to Hungarian Standards (MSZ ISO 5508:1992). The α-amylase in the assay solution was quantified by using an α-amylase standard curve and the activity was expressed as kilo novo units (KNU) per kilogram. 2.3 CALCULATIONS Fat-corrected milk was calculated as FCM (kg/d) = 0.4 × milk, kg/d + 15 × fat, kg/d). Energy-corrected milk was calculated as ECM (kg/d) = milk produc- tion kg × (383 × fat% + 242 × protein% + 165 × lac- tose% + 20.7)/3.140. (1 litre (L) of milk = 1.033 kg of milk). 2.4 STATISTICAL ANALYSIS Evaluation of data was performed by one-factor variant analysis (Kolmogorov-Smirnov test, Levene’s test, t-test) with SPSS 19.0 Windows Program (SPSS Inc., Chi- cago, USA). Acta agriculturae Slovenica, Supplement 5 – 201682 T. TÓTH and R. TÓTHI 3.2 BODY WEIGHT The BW of animals were increased during the trial (Table 3). Mean values of daily live weight changes were improved in the supplemented group which could prob- ably be explained with the more favourable feed conver- sion. 3.3 MILK YIELD AND MILK COMPOSITION Milk yield was significantly (p < 0.05) increased by 1.0 kg/d per cow when the diet was supplemented with enzyme preparation (Table 3). This result is consistent with Harrison and Tricario (2007) and Klingerman et al. (2009). Changes in ruminal fermentation and plasma metabolites suggesting that improved nutrient metabo- lism may be the cause for increased milk production in α-amylase supplemented cows. No effect of treatment (p > 0.05) was observed on the milk DM, milk fat and milk protein while a significant decrease (p < 0.001) was measured in lactose content of milk when cows were sup- plemented with the enzyme preparation (Table 3). This result is differred from Nozière et al. (2014) who found increased lactose content attributable to the α-amylase supplement. No effect of treatment (p > 0.05) was ob- served on the fatty acid content of the milk (Table 4). 4 CONCLUSIONS α-Amylase supplementation has the potential to im- prove milk yield without a reduction in milk fat or milk protein yield. Further research on high-producing cows Item Control Amylase Caprylic acid C8:0 0.02 0.02 Capric acid C10:0 0.02 0.02 Lauric acid C12:0 0.23 0.23 Tridecanoic acid C13:0 0.24 0.23 Myristic acid C14:0 0.63 0.79 Palmitic acid C16:0 26.23 27.53 Heptadecanoic acid C17:0 0.13 0.14 Stearic acid C18:0 7.61 8.34 Arachidic acid C20:0 0.47 0.45 Heneicosanic acid C21:0 0.02 0.02 Behenic acid C22:0 0.32 0.30 Saturated fatty acids 35.88 38.07 Myristoleic acid C14:1 0.07 0.08 Palmitoleic acid C16:1 0.19 0.35 Oleic acid C18:1 23.70 23.12 Elaidic acid 9t-C18:1 0.02 0.02 Vaccenic acid c-C18:1 0.58 0.50 Eicosenoic acid C20:1 0.19 0.18 Monounsaturated fatty acids 24.75 24.25 Linoleic acid C18:2 33.02 31.35 Linolenic acid C18:3 4.87 4.46 Eicosadienoic acid C20:2 0.03 0.03 Eicosapentaenoic acid C20:5 0.03 0.03 Docosapentaenoic acid C22:5 0.04 0.04 Polyunsaturated fatty acids 37.99 35.91 Other fatty acids 1.38 1.77 Table 2: Fatty acid profile of the diets (g/100 g fatty acid) Item Control Amylase BW, kg At the beginning of trial 651 657 At the end of trial 685 697 Milk yield, kg/d 37.7 ± 6.96b 38.7 ± 6.97a 4% FCM yield, kg/d 30.9 31.6 ECM, kg/d 31.3 31.9 Milk fat, % 2.80 ± 0.74 2.78 ± 0.79 Milk protein, % 3.12 ± 0.25 3.11 ± 0.25 Milk lactose, % 4.60 ± 0.16A 4.55 ± 0.22B DM, % 11.34 ± 0.82 11.32 ± 0.94 Table 3: Effect of amylase addition on BW, milk yield and composition a, b p < 0.05; A, B p < 0.001 3 RESULTS AND DISCUSSION 3.1 FEED Composition, analysed nutrition content and fatty acid profile of control and experimental diets (TMR) are summarised in Table 1 and Table 2. Starch content of the diet was in correspondence with Hungarian farm practice (26 % of starch in DM). The assayed α-amylase activity for the control concentrate without enzyme was below limit of detection, and that for the experimental concentrate with enzyme was 561 (472 and 650) KNU/ kg of DM. That equates to activity of 323 (271 and 374) KNU/kg of TMR DM for the experimental diet and no enzyme activity for the control diet. Acta agriculturae Slovenica, Supplement 5 – 2016 83 EFFECT OF FEEDING SUPPLEMENTAL EXOGENOUS AMYLASE ON THE PERFORMANCE OF HIGH YIELDING DAIRY COWS is necessary to assess the usefulness of this exogenous α-amylase on milk production. 5 REFERENCES Cabrita, A. R. J., Bessa, R. J. B., Alves, S. P., Dewhurst, R. J., Fonseca, A. J. M. (2007): Effects of dietary protein and starch on intake, milk production, and milk fatty acid profiles of dairy cows fed corn silage-based diets. Jour- nal of Dairy Science, 90, 1429–1439. Flachowsky, G., Lebzien, P. (1997). Improvement of glu- cose supply for high performing cows. In Proc., 6th Int. Symp. Anim. Nutr., Kaposvár, Hungary (pp. 64–87). Ka- posvar University Press, Kaposvár, Hungary. Gencoglu, H., Shaver, R. D., Steinberg, W., Ensink, J., Fer- raretto, L. F., Bertics, S. J., Lopes, J. C., Akins, M. S. (2010). Effect of feeding a reduced-starch diet with or without amylase addition on lactation performance in dairy cows. Journal of Dairy Science, 93, 723–732. Harrison, G. A., Tricario, J. M. (2007). Case study: Effects of an aspergillus oryzae extract containing α-amylase ac- tivity on lactational performance in commercial dairy herds. The Professional Animal Scientist, 23, 291–297. Hristov, A. N., Basel, C. E., Melgar, A., Foley, A. E., Ropp, J. K., Hunt, C. W., Tricarico, J. M. (2008). Effect of exog- enous polysaccharide-degrading enzyme preparations on ruminal fermentation and digestibility of nutrients in dairy cows. Animal Feed Science and Technology, 145, 182–193. Hungarian Feed Codex (2004). Ministry of Agriculture and Rural Development, Budapest Klingerman, C. M., Hu, W., McDonell, E. E., DerBedrosian M. C., Kung Jr., L. (2009). An evaluation of exogenous enzymes with amylolytic activity for dairy cows. Journal of Dairy Science, 92, 1050–1059. Nozière, P., Steinberg, W., Silberberg, M., Morgavi, D. P. (2014). Amylase addition increases starch ruminal di- gestion in first-lactation cows fed high and low starch diets. Journal of Dairy Science, 97, 2319–2328. Owens, F.N., Secrist, D. S, Hill, W. J., Gill, D. R. (1998). Aci- dosis in cattle: a review. Journal of Animal Science, 76, 275–286. SPSS Base for Windows (2004). Version 13.0. Chicago, IL: SPSS Inc. Weiss, W. P., Steinberg, W., Engstrom, M. A. (2011). Milk production and nutrient digestibility by dairy cows when fed exogenous amylase with coarsely ground dry corn. Journal of Dairy Science, 94, 2492–2499. Item Control Amylase Caprylic acid C8:0 1.03 ± 0.05 1.02 ± 0.04 Capric acid C10:0 2.70 ± 0.20 2.61 ± 0.21 Undecylic acid C11:0 0.34 ± 0.02 0.34 ± 0.02 Lauric acid C12:0 3.62 ± 0.30 3.30 ± 0.13 Tridecanoic acid C13:0 0.21 ± 0.02 0.20 ± 0.01 Myristic acid C14:0 11.91 ± 0.47 11.69 ± 0.11 Pentadecylic acid C15:0 1.21 ± 0.71 1.22 ± 0.02 Palmitic acid C16:0 32.23 ± 1.26 32.72 ± 1.11 Heptadecanoic acid C17:0 0.76 ± 0.06 0.74 ± 0.02 Stearic acid C18:0 9.63 ± 0.32 9.56 ± 0.21 Arachidic acid C20:0 0.15 ± 0.01 0.17 ± 0.01 Heneicosanic acid C21:0 0.03 ± 0.00 0.04 ± 0.01 Saturated fatty acids 63.83 ± 2.46 63.61 ± 2.11 Myristoleic acid C14:1 1.16 ± 0.07 1.16 ± 0.04 Palmitoleic acid C16:1 2.47 ± 0.17 2.43 ± 0.05 Heptadecenoic acid C17:1 0.25 ± 0.03 0.26 ± 0.01 Oleic acid C18:1 22.95 ± 1.71 22.79 ± 0.60 Elaidic acid 9t-C18:1 1.14 ± 0.25 1.25 ± 0.20 Vaccenic acid c-C18:1 0.55 ± 0.11 0.60 ± 0.02 Eicosenoic acid C20:1 0.12 ± 0.01 0.18 ± 0.02 Monounsaturated fatty acids 28.64 ± 1.92 28.67 ± 1.31 Linoleic acid C18:2 (n-6) 2.18 ± 0.15 2.17 ± 0.10 CLA (c9, t11) 0.43 ± 0.05 0.44 ± 0.02 Alpha-linolenic acid C18:3 (n-3) 0.39 ± 0.05 0.40 ± 0.02 Gamma-linolenic acid C18:3 (n-6) 0.02 ± 0.00 0.02 ± 0.00 Eicosadienoic acid C20:2 (n-6) 0.04 ± 0.00 0.04 ± 0.00 Dihomo-gamma-linolenic acid C20:3 (n-6) 0.12 ± 0.01 0.12 ± 0.01 Arachidonic acid C20:4 (n-6) 0.21 ± 0.01 0.19 ± 0.01 Eicosapentaenoic acid C20:5 (n-3) 0.03 ± 0.00 0.03 ± 0.00 Docosadienoic acid C22:2 (n-6) 0.02 ± 0.01 0.02 ± 0.00 Docosatetraenoic acid C22:4 (n-6) 0.04 ± 0.00 0.04 ± 0.00 Docosapentaenoic acid C22:5 (n-3) 0.05 ± 0.01 0.06 ± 0.00 Polyunsaturated fatty acids 3.53 ± 0.25 3.53 ± 0.11 Other fatty acids 4.00 4.19 Table 4: Fatty acid profile of milk produced in the morning (g/100 g fatty acid; n = 12)