Veterinary Archives, Vol. 91 No. 5, 2021.
Original scientific paper
https://doi.org/10.24099/vet.arhiv.1036
The effects of Pinus brutia bark extract on pure and mixed continuous cultures of rumen bacteria and archaea, and fermentation characteristics in vitro
Ahu Demirtas
orcid.org/0000-0003-2942-6243
; Department of Physiology, Faculty of Veterinary Medicine, Burdur Mehmet Akif Ersoy University, Burdur, Turkey
Saad A. A. Musa
; Department of Physiology, Faculty of Veterinary Medicine, Ankara University, Diskapi, Ankara, Turkey
Yasemin Salgirli-Demirbas
; Department of Physiology, Faculty of Veterinary Medicine, Ankara University, Diskapi, Ankara, Turkey
Hakan Ozturk
; Department of Physiology, Faculty of Veterinary Medicine, Ankara University, Diskapi, Ankara, Turkey
Mert Pekcan
; Department of Biochemistry, Faculty of Veterinary Medicine, Ankara University, Diskapi, Ankara, Turkey
Nese N. Toprak
; Department of Animal Science, Faculty of Agriculture, Ankara University, Diskapi, Ankara, Turkey
Etkin Safak
orcid.org/0000-0003-3869-3749
; Department of Physiology, Faculty of Veterinary Medicine, Ankara University, Diskapi, Ankara, Turkey
Melis Unler
; Department of Physiology, Faculty of Veterinary Medicine, Ankara University, Diskapi, Ankara, Turkey
Begum Saral
; Department of Physiology, Faculty of Veterinary Medicine, Ankara University, Diskapi, Ankara, Turkey
Mehmet B. Emre
; Department of Physiology, Faculty of Veterinary Medicine, Ankara University, Diskapi, Ankara, Turkey
Abstract
The aim of the study was to investigate the effects of Pinus brutia bark extract, which is rich in polyphenolic compounds of tannins, on both pure and mixed continuous cultures of rumen bacteria and archaea, as well as on rumen fermentation characteristics in vitro. Antimicrobial susceptibility assay with pure cultures was carried out in an anaerobic chamber. Pinus brutia bark extract exhibited a potential inhibitor activity (P<0.05) against pure cultures of Ruminococcus flavefaciens, Eubacterium ruminantium, and Methanobacterium formicicum while a growth stimulatory effect (P<0.05) was observed for Ruminoccocus albus, Butyrivibrio fibrisolvens, and Streptococcus bovis. Pinus brutia bark extract only had a potential inhibitor effect (P<0.05) on R. albus at the highest dose (1200 μg/mL). Pinus brutia bark extract also stimulated (P<0.05) the growth of pure cultures of Fibrobacter succinogenes, while it did not affect Megasphaera elsdenii, except at the highest dose. The effects of two doses (75 and 375 mg/L) of P. brutia bark extract on in vitro mixed cultures and rumen fermentation parameters were determined by the rumen simulation technique (Rusitec). Supplementation with P. brutia bark extract led to a quadratic decrease (P<0.05) in the cell numbers of R. flavefaciens. Production of total and individual short chain fatty acids (SCFA), acetate to propionate ratio (C2/C3), total protozoa, ruminal pH, and dry matter digestibility (DMD) did not change in the presence of P. brutia bark extract. Supplementation with both doses of P. brutia bark extract decreased (P<0.05) the ammonia-N concentrations. Ammonia-N concentration was lowest in the high-supplemented group (P<0.05). As a conclusion, inhibitory effects of P. brutia bark extract on some species in the pure cultures were in the same direction as with mixed ruminal cultures, while stimulatory effects disappeared. The lack of inhibitory effects on protozoa and on a large number of Gram-positive rumen bacteria in the mixed cultures suggests that its mechanism of action is not exactly similar to antibiotics. Although P. brutia bark extract did not alter ruminal SCFA, it could have potential to improve ruminal protein utilization without depressing rumen microbial fermentation.
Keywords
Pinus brutia bark; rumen bacteria; anaerobic chamber; rumen fermentation; rusitec; tannins
Hrčak ID:
271611
URI
Publication date:
12.12.2021.
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