Effects of probiotics on in vitro ruminal profile and population of some cellulolytic bacteria

Abstract

The aim of this study was to evaluate the effects of probiotics on ruminal pH, ammonia nitrogen, production of short chain fatty acids (SCFA) and number of Ruminococcus albus and Ruminococcus flavefaciens. The probiotics blend was tested in vitro for 48 h incubation using "Hohenheim Futterwert Test" (HFT). There was no interaction effect of the treatment and incubation time on the ruminal pH and ammonia-nitrogen concentration. A supplemental probiotics blend tended to increase the total SCFA concentration in comparison to the non-supplemented control fermenter fluids (P> 0.05). There was a significant interaction effect of the treatment groups and incubation time on butyrate (P=0.042), valerate (P=0.045) and isovalerate (P= 0.028) concentrations. Total protozoa and total bacteria numbers were higher in probiotics supplemented fluid than in non-supplemented control fluid (P<0.001 and P<0.01, respectively). Dietary supplementation of a probiotics blend to the fermenters did not influence (P>0.05) the number of copies of R. albus. However, the population of R. flavafaciens was lower (P<0.01) in the probiotic supplemented group as compared with the non-supplemented control group. Our results showed that the probiotics blend might modulate both microbial metabolic activity and the population of ruminal microorganisms.

Influence of direct-fed microbial blend and Ferula elaeochytris on in vitro rumen fermentation pattern and degradability during simulated ruminal acidosis

“…Although the pH of the rumen fluid was significantly lower in all artificial acidosis groups, the supplementation did not change the situation either both groups in the present study, similarly to previous studies, where that probiotic blend and FE did not alter the ruminal pH, ammonia N or VFA concentrations ( 21 , 35 ). This could be due to the severity of the mimicked acidosis condition ( 29 ).…”

“…Thus, each feed additive-supplemented substrate was incubated separately under two different pH levels (normal and acidosis). Dosages were moderate in comparison to previous in vitro screening studies (21,35). The syringes, previously heated in the incubator to 39°C, were filled with mixed buffered ruminal fluid that was immediately bubbled with CO2.…”

“…Several studies have been conducted on potential feeding strategies to decrease the incidence of acidosis, such as providing additives including buffers, yeasts, plant extracts and probiotics ( 32 ). In particular, the use of probiotics has attracted interest because of their protective effect against acidosis ( 35 ). A blend of probiotics showed higher efficacy than single strain probiotics in strengthening animal health ( 9 , 24 ).…”