Effect of increased intake of concentrates and sodium butyrate supplementation on reticulorumen macroanatomy and reticulorumen fermentation in growing rams

• Published in: Animal (Cambridge, England) Vol. 17; no. 11; p. 100899
• Main Authors: Samanta, Świerk, Marcin, Przybyło, Izabela, Wajsman, Edyta, Molik, Renata, Miltko, Paweł, Górka
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01-11-2023; Elsevier
• Subjects: Acidosis; Forestomach; Rumen fermentation; Short-chain fatty acids; Xylanolytic activity; Short-chain fatty acids; Xylanolytic activity; Forestomach; Acidosis; Rumen fermentation
• ISSN: 1751-7311; 1751-732X
• DOI: 10.1016/j.animal.2023.100899

•High intake of concentrates is known to negatively affect rumen function.•It was hypothesised that high ruminal butyrate may also challenge the rumen.•High intake of concentrates reduced fibrolytic activity in the rumen.•Similar effect was observed when sodium butyrate was supplemented in the diet.•The latter one could be partially a result of increased sodium intake.
Increased ruminal butyrate production is considered to have mostly positive impacts on rumen macro- and microanatomy and its functions. However, excessive ruminal butyrate production may also affect the rumen negatively. Forty-two growing rams were allocated into six treatments and fed a diet with low (22.5% of diet DM; LOW) or high (60% of diet DM; HIGH) inclusion of concentrates in combination with no, low (1.6% of diet DM) or high (3.2% of diet DM) sodium butyrate (SB) supplementation to obtain low or high reticuloruminal (RR) pH with different concentrations of butyrate. Both absolute (L/day) and relative (% of BW) water intake increased linearly with increasing dose of SB (P ≤ 0.02). The RR fluid pH was lower for HIGH compared to LOW treatments (P < 0.01) but was not affected by SB supplementation (P = 0.35). Total SCFA concentration, propionate and valerate concentrations (mmol/L) in the RR fluid were higher for HIGH compared to LOW treatments (P ≤ 0.01), but were not affected by SB supplementation (P ≥ 0.22). Reticuloruminal butyrate was higher for HIGH compared to LOW treatments and increased linearly with increasing dose of SB (P < 0.01). High concentrate inclusion in the diet (P < 0.01) decreased and SB supplementation tended to (P = 0.10) decrease fibrolytic activity in the RR. Increasing doses of SB linearly decreased acetate, isovalerate and NH3-N concentrations in RR fluid, and RR digesta DM weight (g DM/kg BW; P ≤ 0.02). Relative RR and rumen tissue weights (g/kg BW) were higher for LOW compared to HIGH (P ≤ 0.03) treatments but were not affected by SB inclusion in the diet (P ≥ 0.35). Also, there was no impact of concentrates or SB inclusion in the diet on ruminal epithelium DM weight (mg/cm2), either in the ventral or dorsal sac of the rumen (P ≥ 0.14). Under conditions of the current study, SB supplementation in the diet decreased RR digesta DM concentration and weight, acetate, isovalerate and NH3-N concentration in the RR fluid, and tended to reduce fibrolytic activity in the RR. At least part of this response could be due to increased intake of water, and consequently passage of digesta from the RR to lower regions of the gastrointestinal tract.