Effect of feeding of different sources of NPN on production performance of dairy cows.

Received: 2016-04-11 | Accepted: 2016-05-04 | Available online: 2016-12-22http://dx.doi.org/10.15414/afz.2016.19.04.163-166The aim of the study was to analyse the effect of feeding of different sources of NPN on nutrient utilization and production performance of dairy cows under field conditions. Balancing diets for crude protein without consideration of protein quality or rumen degradability often led to overfeeding of nitrogen and less than optimum production. High yielding dairy cows separated in two groups with 85 resp. 80 cows in each were set up for the trial. Groups were consistent according the stage of production and reproduction cycle as well as age structure. Both groups were fed concentrate mixture with the same composition with only difference in NPN/ microbial protein source, with same dosage of 100 g per cow and day. Field trial was performed for period of 3 subsequent months. Performance data were collected in accordance with official milk recording. In both groups majority of cows were on first lactation. Significant differences in daily milk production were observed 2.87 kg (P<0.01) for group 2, in fat content 0.07 % for group 2 non-significant, whereas in protein content 0.18% for group 1 significant (P<0.01) in case of first lactations. If considering  first tree lactations, group 2 produced 1.7 kg milk per day more (P<0.08), with 0.05% fat more and 0.002 % protein less than group 1. The space created in dry matter intake by a concentrated slow-release NPN can be filled with high quality forage that could reduce the cost of feeding while maintaining levels of production. Keywords: Holstein, slow-release urea, microbial protein, milk yieldReferences Bíro, D., Gálik, B., Juráček, M. et al. (2009) Effect of Biological and Biochemical Silage Additives on Final Nutritive, Hygienic and Fermentation Characteristics of Ensiled High Moisture Crimped Corn. Acta Veterinaria Brno, vol. 78 (4), pp. 691-698 doi: http://dx.doi.org/10.2754/avb200978040691Bouška J. et al. (2006) Chov dojeného skotu, Profi Press, Praha, 2006Cantalapiedra-Hijar, G., Peyraud, J. L., Lemosquet, S. et al. (2014) Dietary carbohydrate composition modifies the milk N efficiency in late lactation cows fed low crude protein diets. Animal, vol. 8 (2), pp. 275-285 doi: http://dx.doi.org/10.1017/S1751731113002012Cappellozza, B. I., Bohnert, D. W., Schauer, C. S. et al.  (2013) Daily and alternate day supplementation of urea or soybean meal to ruminants consuming low-quality cool-season forage: II. Effects on ruminal fermentation Livestock Science, vol. 155 (2-3), pp. 214-222 doi: http://dx.doi.org/10.1016/j.livsci.2013.05.002De Boever, J. L., Blok, M. C., Millet, S. et al. (2014) The energy and protein value of wheat, maize and blend DDGS for cattle and evaluation of prediction methods. Animal, vol. 8(11), pp 1839–1850  doi: http://dx.doi.org/10.1017/S1751731114001815Harrison, G. A. and Karnezos T. P. (2005) Can we improve efficiency of nitrogen utilization in the lactating cow? Recent Advances in Animal Nutrition, vol. 15, 2005, 001-011pp.Hazuchová E. and Kasarda R. (2010) Evaluation of body condition score of lactating cows. 61st EAAP Annual Meeting, Heraklion. 2010. Book of Abstracts. 34, 26,p. 375Holder  Vaughn B., El-Kadi, Samer W., Tricarico, Juan M. et al. (2013) The effects of crude protein concentration and slow release urea on nitrogen metabolism in Holstein steers. Archives of Animal Nutrition, vol. 67 (2), pp. 93-100 doi: http://dx.doi.org/10.1080/1745039X.2013.773647Kudrna V. and Homolka P. (2009) Vliv diety, zejména obsahu dusíkatých látek, na množství a kvalitu mléčné bílkoviny a zdraví dojnic, Výskumný ústav živočišné výroby, Praha – Uhříněves, 2009McGuire D. L., Bohnert, D. W., Schauer, C. S. et al. (2013) Daily and alternate day supplementation of urea or soybean meal to ruminants consuming low-quality cool-season forage: I-Effects on efficiency of nitrogen use and nutrient digestion  Livestock Science, vol. 155, (2-3), pp. 205-213 doi: http://dx.doi.org/10.1016/j.livsci.2013.05.015Šimko, M., Čerešňáková, Z. Bíro, D. et al. (2010) Influence of Wheat and Maize Starch on fermentation in the Rumen, Duodenal Nutrient Flow and Nutrient Digestibility. ActaVeterinaria Brno, vol. 79 (4), pp. 533-541 doi: http://dx.doi.org/10.2754/avb201079040533Zeman, L. et al.(2006)  Výživa a krmení hospodářských zvířat., Profi Press, Praha, 2006

The effect of dha omega-3 feeding in the high yielding holstein herd

The aim of this study was to analyse the effect of supplementary feeding of DHA (Docosahexaenoic Acid) rich algae product (Algae STM Alltech Inc.) on production of milk, fat and protein as well as on reproduction of high yielding Holstein dairy herd. Field trial was set up on Top 10 dairy farm in western part of Slovakia, under commercial conditions. The data of high yielding dairy cows, separated in two groups of 30 (control) and 29 (trial) animals, were recorded for period of 3 subsequent months from October to December 2015. Animals were fed once a day Total Mixed Ration based diet with different feed mixture composition in trial group (+100 g Algae STM Alltech Inc. per cow and day). Performance data were collected in accordance with official milk recording system of Breeding Services of Slovak Republic s. e. and milk samples were collected once per month according to the A4 standard methodology. The control group showed higher level of milk production compared to trial. Our study indicated that the feeding of algae caused milk fat depression and generally lower protein content in milk. Significant impact of algae feeding was found also for the level of urea in milk. In addition, the supplementary feeding of DHA may represent effective strategy to increase the percentage of pregnancies per inseminations in lactating dairy cows