Publikationsdatenbank

Ruminal and intestinal calcium absorption in growing sheep:
acute and long-term effects of a menthol-containing feed additive (2019)

Art

Vortrag

Autoren

Geiger, Sebastian (WE 2)

Patra, Amlan K. (WE 2)

Schrapers, Katharina T.

Aschenbach, Jörg R. (WE 2)

Kongress

International Symposium on Ruminant Physiology (ISRP 2019)

Leipzig, 03. – 06.09.2019

Quelle

Advances in Animal Biosciences

Bandzählung: 10

Heftzählung: 3

Seiten: 389

ISSN: 2040-4719

Sprache

Englisch

Verweise

URL (Volltext): https://www.cambridge.org/core/services/aop-cambridge-core/content/view/7D464B8882B4D5304683797665CD9E5E/S2040470019000037a.pdf/proceedings_of_the_xiiith_international_symposium_on_ruminant_physiology_isrp_2019.pdf

Kontakt

Institut für Veterinär-Physiologie

Oertzenweg 19 b
14163 Berlin
+49 30 838 62600
physiologie@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Introduction:
A considerable amount of calcium is absorbed in the rumen although the classical calcium transport proteins TRPV5 and TRPV6 are not expressed. Recent studies suggested the involvement of TRPV3 in ruminal calcium absorption and the TRPV3 agonist menthol indeed increased calcium absorption in isolated ruminal epithelium. The present study investigated if either pre-feeding with a menthol-containing feed additive or direct application of menthol influences calcium absorption across ruminal and intestinal epithelia of growing sheep ex vivo.

Material and methods:
Twenty four growing sheep were allotted into three groups in a randomized block design. They received hay ad libitum and 600 g concentrate feed. The latter contained either no additives (control diet) or plant bioactive lipid compounds (PBLC) with menthol as lead compound (feed additive OAX17, PerformaNat GmbH) in a low or high dose (PBLC low, 80 mg/d or PBLC high, 160 mg/d, respectively) for at least 28 d. Ruminal and jejunal tissues were mounted in Ussing chambers for measurement of unilateral calcium flux rates in the presence and absence of 50 μM menthol. Net flux rates were calculated and analyzed using mixed model procedures of SAS.

Results:
The basal net flux rate of calcium was about 7 times higher in rumen than in jejunal tissue. In jejunum, PBLC feeding decreased net calcium flux rate before and after menthol application (p<0.05), and the acute menthol application did not alter net calcium flux rates within feeding groups (p>0.1). Ruminal net calcium flux rate was highest in the PBLC low group (quadratic effect, p<0.05). Menthol addition increased calcium net flux rate in all groups (p<0.05) but epithelia from sheep pre-fed with PBLC showed a stronger increase compared to control sheep (p<0.05).

Discussion:
The present study confirmed that menthol increases ruminal calcium absorption, possibly by activating the ruminal TRPV3 channel. Pre-feeding with PBLC increased ruminal calcium absorption and responsiveness to menthol in a dose dependent manner. In jejunum, PBLC feeding decreased calcium absorption, which may be linked to different calcium transporting channels as the intestinal calcium-absorbing channels, TRPV5 and TRPV6, are regulated by vitamin D3. The results suggest that menthol-containing PBLC effectively modulate calcium absorption in rumen.