Resumen:
The current study aimed to evaluate if the effect of Saccharomyces cerevisiae (SC) on in vitro fermentation
can be affected with the crude protein (CP) content of the ration. Three commercial SC cultures of Biocell
F53®, Procreatin 7®, and Biosaf SC47® were evaluated at 0 (SC0), 2 (SC2), and 4 (SC4) mg/g dry matter (DM)
of substrate. Two rations with 13% (low crude protein [LCP]) and 16% CP (high crude protein [HCP]) were
used as substrates. Rumen gas (gas production [GP]) and methane (CH4) productions were recorded. The
HCP ration had increased (P = .05) asymptotic GP, CH4 production, and fermentation parameters. Biocell
F53® and Biosaf SC47® increased the asymptotic GP (P < .05) in HCP and LCP rations with better effect
for the dose of 2 mg/g DM substrate HCP (P < .05) and dose of 4 mg yeast/g DM substrate with the
LCP ration. The highest CH4 production was observed (P < .05) with Procreatin 7®. It could be
concluded that HCP ration improved GP than LCP ration. Moreover, addition of Biocell F53® and Biosaf
SC47® at rate of 2 mg/g DM improved fermentation kinetics and nutrients degradability
Descripción:
One of the most important problems facing ruminant production
is the losing of energy and high biological value proteins
as a result of ruminal fermentation. This may cause a
limited productive performance (Kholif et al. 2014; Ahmed
et al. 2016) and release of pollutants to the environment (Calsamiglia
et al. 2007). Ionophores and antibiotics have good results
to reduce these losses in energy and protein (McGuffey et al.
2001); however, the European Union banned the use of them
due to the potential of appearance of residues in milk or
meat (Russell and Houlihan 2003). Nowadays, researches are
concerning the use of natural feed additives, generally recognized
as safe for human consumption, including phytogenic
extracts (Valdes et al. 2015), enzymes (Alsersy et al. 2015) or Saccharomyces
cerevisiae (SC) (Elghandour, Salem et al. 2015) to
modify rumen microbial fermentation.
