Two stories at the Silage conference in Bonn were about propylene glycol content of silage, and how that could be influenced by silage.
Lau et al. (2018) described that Lactobacillus Buchneri in relatively wet, sugar-rich pits led to substantially higher propylene glycol levels in grass pits Compared to Lactobacillus Plantarum and control treatment. Grass pits Waaaraan L. Buchneri was added contain CA 1.9 PG on DS basis while control pits and Pits with L. Plantarum do not contain more THAN 0.1 and 0.04 PG. See also showed a negative link between DS content and PG and a positive link between sugar content and PG.
Lau, Kramer, and Hummel (2018) described the influence of PG content of pits on BHBA in blood from dairy cows. PG content in pits was increased by use of L. Buchneri. In this test the grass with high PG content contained 3.89 PG and the grass with low PG 0.06. BHBA levels of cows that got the grass with high PG were substantially lower than from cows that got the grass with low PG content. The cows that received the grass with a lot of PG also produced more milk with higher protein content and lower fat content in the research period.
These results correspond to the results of Nishino et al. (2003), which found a substantieele increase of PG in cut corn by inoculation with L. Buchneri. It is well known that whether the feeding of propylene glycol is an effective way to counteract ketosis in fresh cows (Chung et al. (2009)), but interestingly enough is drenchen or top-dressing effective than interfering in the ration (Chung et al (2009)). The results of Lau et al. (2018) and Lau, Kramer, and Hummel (2018), however, make us think very differently about silage agents with L. Buchneri.
Chung, Y.-H., N.E. Brown, C.M. Martinez, I.E Cassidy, and G.A. Varga. 2009. “Effects of rumen-protected choline and dry propylene glycol on feed intake and blood parameters for Holstein dairy cows in early lactation.” Journal of Dairy Science 92 (6). Elsevier: 2729 – 36. https://doi.org/10.3168/jds.2008-1299.
Lau, N., M. Huenerberg, E. Kramer, and J. Hummel. 2018. “Impact of various silage additives on propylene glycol content of grass silages.” In XVIII International Silage Conference 2018, edited by K. Gerlach and K. H. Südekum, 310 – 11. Bonn. https://www.isc2018.de/Download/Proceedings.
Lau, N., E. Kramer, and J. Hummel. 2018. “Impact of grass silage with high levels of propylene glycol on ketosis prophylaxis during transition phase and early lactation.” In XVIII International Silage Conference 2018, edited by K. Gerlach and K. H. Südekum, 308 – 9. Bonn. https://www.isc2018.de/Download/Proceedings.
Nishino, Naoki, M. Yoshida, H. Shiota, and E. Sakaguchi. 2003. “Accumulation of 1.2-propanediol and enhancement of aerobic stability in whole crop maize silage inoculated with Lactobacillus buchneri.” Journal of Applied Microbiology 94 (5): 800 – 807. https://doi.org/10.1046/j.1365-2672.2003.01810.x.