Effects of calcium propionate on the fermentation quality and aerobic stability of alfalfa silage

  • Dong, Zhihao (Institute of Ensiling and Processing of Grass, Nanjing Agricultural University) ;
  • Yuan, Xianjun (Institute of Ensiling and Processing of Grass, Nanjing Agricultural University) ;
  • Wen, Aiyou (Institute of Ensiling and Processing of Grass, Nanjing Agricultural University) ;
  • Desta, Seare T. (Institute of Ensiling and Processing of Grass, Nanjing Agricultural University) ;
  • Shao, Tao (Institute of Ensiling and Processing of Grass, Nanjing Agricultural University)
  • Received : 2016.12.13
  • Accepted : 2017.03.21
  • Published : 2017.09.01


Objective: To assess the potency of calcium propionate (CAP) used as silage additive, an experiment was carried out to evaluate the effect of CAP on the nitrogen transformation, fermentation quality and aerobic stability of alfalfa silages. Methods: Alfalfa was ensiled with four levels of CAP (5, 10, 15, and 20 g/kg of fresh weight [FW]) in laboratory silos for 30 days. After opening, the silages were analyzed for the chemical and microbiological characteristics, and subjected to an aerobic stability test. Results: The increasing proportion of CAP did not affect pH, lactic acid (LA) concentrations and yeast counts, while linearly decreased counts of enterobacteria (p = 0.029), molds (p<0.001) and clostridia (p<0.001), and concentrations of acetic acid (p<0.001), propionic acid (p<0.001), butyric acid (p<0.001), and ethanol (p = 0.007), and quadratically (p = 0.001) increased lactic acid bacteria counts. With increasing the proportion of CAP, the dry matter (DM) loss (p<0.001), free amino acid N (p<0.001), ammonia N (p = 0.004), and non-protein N (p<0.001) contents were linearly reduced, whereas DM (p = 0.048), water soluble carbohydrate (p<0.001) and peptide N (p<0.001) contents were linearly increased. The highest Flieg's point was found in CAP10 (75.9), represented the best fermentation quality. All silages treated with CAP improved aerobic stability as indicated by increased stable hours compared with control. Conclusion: The addition of CAP can suppress the undesirable microorganisms during ensiling and exposure to air, thereby improving the fermentation quality and aerobic stability as well as retarding the proteolysis of alfalfa silage. It is suggested that CAP used as an additive is recommended at a level of 10 g/kg FW.


Alfalfa;Calcium Propionate;Fermentation Quality;Aerobic Stability


Supported by : National Natural Science Foundation of China, Central Universities


  1. McDonald P, Henderson N, Heron S. The biochemistry of Silage. 2nd ed. Marlow, UK: Chalcombe Publishers; 1991.
  2. Woolford MK. Microbiological screening of the straight chain fatty acids (c1-c12) as potential silage additives. J Sci Food Agric 1975;26:219-28.
  3. Kung L, Myers CL, Neylon JM, et al. The effects of buffered propionic acid-based additives alone or combined with microbial inoculation on the fermentation of high moisture corn and whole-crop barley. J Dairy Sci 2004;87:1310-6.
  4. Woolford MK. Antimicrobial effects of mineral acids, organic acids, salts and sterilizing agents in relation to their potential as silage additives. Grass Forage Sci 1978;33:131-6.
  5. Lambert RJ, Stratford M. Weak-acid preservatives: modelling microbial inhibition and response. J Appl Microbiol 1999;86:157-64.
  6. Li P, Ji S, Hou C, et al. Effects of chemical additives on the fermentation quality and N distribution of alfalfa silage in south of China. Anim Sci J 2016;87:1472-9.
  7. Ashbell G, Theune HH, Sklan D. Changes in amino acid compounds of wheat plants during ensiling and aerobic exposure: the influence of propionic acid and urea phosphate-calcium propionate. J Sci Food Agric 1984;102:667-72.
  8. Arbabi S, Ghoorchi T, Hasani S. The effect of delayed ensiling and application of an organic acid-based additives on the fermentation of corn silage. Asian J Anim Vet Adv 2009;4:219-27.
  9. Thomas TA. An automated procedure for the determination of soluble carbohydrates in herbage. J Sci Food Agric 1977;28:639-42.
  10. Winters AL, Lloyd JD, Jones R, Merry RJ. Evaluation of a rapid method for estimating free amino acids in silages. Anim Feed Sci Technol 2002;99:177-87.
  11. Muck RE. Dry matter level effects on alfalfa silage quality. I. Nitrogen transformations. Trans ASAE 1987;30:7-14.
  12. Shao T, Wang T, Shimojo M, Masuda Y. Effect of ensiling density on fermentation quality of guineagrass (Panicum maximum Jacq.) silage during the early stage of ensiling. Asian-Australas J Anim Sci 2005;18:1273-8.
  13. Yuan X, Wen A, Desta ST, Dong Z, Shao T. Effects of 4 short-chain fatty acids or salts on dynamics of nitrogen transformations and intrinsic protease activity of alfalfa silage. J Sci Food Agric 2017;97:2759-66.
  14. Moselhy MA, Borba JP, Borba AES. Improving the nutritive value, in vitro digestibility and aerobic stability of Hedychium gardnerianum silage through application of additives at ensiling time. Anim Feed Sci Technol 2015;206:8-18.
  15. Nkosi BD, Meeske R. Effects of ensiling totally mixed potato hash ration with or without a heterofermentative bacterial inoculant on silage fermentation, aerobic stability, growth performance and digestibility in lambs. Anim Feed Sci Technol 2010;161:38-48.
  16. Silva VP, Pereira OG, Leandro ES, et al. Effects of lactic acid bacteria with bacteriocinogenic potential on the fermentation profile and chemical composition of alfalfa silage in tropical conditions. J Dairy Sci 2016;99:1895-902.
  17. Ogunade IM, Kim DH, Jiang Y, et al. Control of Escherichia coli O157:H7 in contaminated alfalfa silage: effects of silage additives. J Dairy Sci 2016;99:4427-36.
  18. Woolford MK. The antimicrobial spectra of some salts of organic acids and glutaraldehyde in respect to their potential as silage additives. Grass Forage Sci 1984;39:53-7.
  19. Castle ME, Watson JN. Silage and milk production: studies with molasses and formic acid as additives for grass silage. Grass Forage Sci 1985;40:85-92.
  20. Yuan X, Yu C, Shimojo M, Shao T. Improvement of fermentation and nutritive quality of straw-grass silage by inclusion of wet hulless-barley distillers' grains in Tibet. Asian-Australas J Anim Sci 2012;25:479-85.
  21. Muck RE. Factors influencing silage quality and their implications for management. J Dairy Sci 1988;71:2992-3002.
  22. Silva TCD, Smith ML, Barnard AM, Kung L. The effect of a chemical additive on the fermentation and aerobic stability of high-moisture corn. J Dairy Sci 2015;98:8904-12.
  23. Guo X, Zhou H, Yu Z, Zhang Y. Changes in the distribution of nitrogen and plant enzymatic activity during ensilage of lucerne treated with different additives. Grass Forage Sci 2007;62:35-43.
  24. Jones BA, Hatfield RD, Muck RE. Characterization of proteolysis in alfalfa and red clover. Crop Sci 1995;35:537-41.
  25. Kleinschmit DH, Schmidt RJ, Kung Jr L. The effects of various antifungal additives on the fermentation and aerobic stability of corn silage. J Dairy Sci 2005;88:2130-9.
  26. Muck RE, O'Kiely P. Aerobic deterioration of lucerne (Medicago sativa) and maize (Zea mais) silages-effects of fermentation products. J Sci Food Agric 1992;59:145-9.
  27. Ashbell G, Weinberg ZG, Hen Y, Filya I. The effects of temperature on the aerobic stability of wheat and corn silages. J Ind Microbiol Biot 2002;28:261-3.
  28. Kung L, Sheperd AC, Smagala AM, et al. The Effect of preservatives based on propionic acid on the fermentation and aerobic stability of corn silage and a total mixed ration. J Dairy Sci 1998;81:1322-30.

Cited by

  1. Fermentation quality and aerobic stability of mulberry silage prepared with lactic acid bacteria and propionic acid pp.13443941, 2019,
  2. Fermentation dynamics and diversity of bacterial community in four typical woody forages pp.1869-2044, 2019,
  3. Characterization of nitrogen transformation dynamics in alfalfa and red clover and their mixture silages pp.17446961, 2019,