Manipulation of rumen ecology by dietary lemongrass (Cymbopogon citratus Stapf.) powder supplementation.
This experiment was conducted to investigate the effect of lemongrass [Cymbopogon citratus (DC.) Stapf.] powder (LGP) on rumen ecology, rumen microorganisms, and digestibility of nutrients. Four ruminally fistulated crossbred (Brahman native) beef cattle were randomly assigned according to a 4 x 4 Latin square design. The dietary treatments were LGP supplementation at 0, 100, 200, and 300 g/d with urea-treated rice straw (5%) fed to allow ad libitum intake. Digestibilities of DM, ether extract, and NDF were significantly different among treatments and were greatest at 100 g/d of supplementation. However, digestibility of CP was decreased with LGP supplementation (P < 0.05), whereas ruminal NH(3)-N and plasma urea N were decreased with incremental additions of LGP (P < 0.05). Ruminal VFA concentrations were similar among supplementation concentrations (P > 0.05). Total viable bacteria, amylolytic bacteria, and cellulolytic bacteria were significantly different among treatments and were greatest at 100 g/d of supplementation (4.7 x 10(9), 1.7 x 10(7), and 2.0 x 10(9) cfu/mL, respectively). Protozoal populations were significantly decreased by LGP supplementation. In addition, efficiency of rumen microbial N synthesis based on OM truly digested in the rumen was enriched by LGP supplementation, especially at 100 g/d (34.2 g of N/kg of OM truly digested in the rumen). Based on this study, it could be concluded that supplementation of LGP at 100 g/d improved digestibilities of nutrients, rumen microbial population, and microbial protein synthesis efficiency, thus improving rumen ecology in beef cattle.
Wanapat
M
M
Tropical Feed Resources Research and Development Center (TROFREC), Faculty of Agriculture, Khon Kaen University, Khon Kaen, 40002, Thailand. metha@kku.ac.th
Cherdthong
A
A
Pakdee
P
P
Wanapat
S
S
D000821:Animal Feed / Q000032:analysis; D000818:Animals; D018407:Bacterial Physiological Phenomena; D001426:Bacterial Proteins / Q000096:biosynthesis; D001806:Blood Urea Nitrogen; D002417:Cattle / Q000378:metabolism / Q000382:microbiology*; D031743:Cymbopogon / Q000378:metabolism*; D004032:Diet / Q000662:veterinary*; D019587:Dietary Supplements; D004063:Digestion / Q000502:physiology; D004435:Eating / Q000502:physiology; D005232:Fatty Acids, Volatile / Q000097:blood; D005285:Fermentation / Q000502:physiology; D008297:Male; D009584:Nitrogen / Q000378:metabolism; D011208:Powders / Q000008:administration & dosage; D011897:Random Allocation; D012417:Rumen / Q000378:metabolism / Q000382:microbiology*
D001426:Bacterial Proteins; D005232:Fatty Acids, Volatile; D011208:Powders; D009584:Nitrogen