In vitro digestibility using caecal liquor of diets containing poor quality roughages and green forages fed to domesticated ostriches ( Struthio camelus var. domesticus)

• Published in: Animal feed science and technology Vol. 119; no. 3; pp. 283 - 291
• Main Authors: Nheta, C., Topps, J.H., Dzama, K., Kusina, J., Mugabe, P.H.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 04.04.2005; Elsevier
• Subjects: alternative livestock; Biological and medical sciences; cecum; dietary fiber; digestibility; digestive juices; experimental diets; Feed and pet food industries; Food industries; forage; forage composition; forage quality; Forages; Fundamental and applied biological sciences. Psychology; In vitro; in vitro digestibility; livestock feeding; metabolizable energy; Ostrich diets; ostriches; Tilley and Terry; Tilly and Terry method; Tilley and Terry; In vitro; Ostrich diets; Forages; Diet; Quality; Fodder; Digestibility
• ISSN: 0377-8401; 1873-2216
• DOI: 10.1016/j.anifeedsci.2004.02.003

The objective of this study was to compare in vitro organic matter digestibility (IVOMD) of ostrich diets using the normal (NTT) and reverse (RTT) modified Tilley and Terry methods of in vitro digestion. The IVOMD values of green forages were determined using the RTT method only. Four ostrich diets and four green forages were digested in vitro using caecal liquor collected from ostriches slaughtered at the Norton Commercial ostrich producers (Copro) abattoir. The diets included a control diet of a concentrate and legume hay, silverleaf desmodium uncinatum (CN), and the three others consisting of a concentrate with either veld hay (VH), Katambora Rhodes grass hay (RG) or maize stover (MS). Lucerne (LU), Midmar Rye grass (MRG), Russian Comfrey (RC) and Kenyan White clover (KWC) were the green forages used. The forages were grown under the recommended management levels and were cut before flowering. There was no interaction ( P>0.05) between diet and method of digestion. The RTT gave higher ( P<0.01) IVOMD than the NTT method. However, both methods showed a similar trend in the digestion of the diets. The MS and RG diets had similar and greater ( P<0.05) IVOMD than the control and veld hay diets. The amounts of organic matter (OM) digested differed ( P<0.01) with either diet or forage type. Kenyan White clover and MRG had similar and greater ( P<0.05) IVOMD than LU and RC, which were not different ( P>0.05). The values of IVOMD in dry matter for the forages were: MRG > KWC > LU > RC, and all the differences were significant ( P<0.05). The study showed that the NTT method needs to be modified to suit hind gut fermenters and IVOMD can, therefore, be used to rank the nutritive value of ostrich feeds.