Abstract
Four Small‐tail Han male hogget sheep, fitted with rumen cannula and fed the same basal diet were used to study the impacts of docusate (DOC) and fauna‐free on the voluntary feed intake (VFI), and ruminal protozoal, bacterial and fungal counts and the digestive enzyme activities. By a 4 × 4 Latin square design, sheep were given no DOC (the control), 2 doses of DOC: 1.2 and 3.0 g/kg diet or oral dose of 6.0 g/d DOC for three days (fauna‐free treatment) in each period of 18 days, the last three days of which were for sampling the rumen fluid. Compared with the control, 1.2 g/kg of DOC supplementation significantly resulted in increases of 18.0% VFI and 44% bacterial count, and no significant change in the fungal number. Supplementing DOC reduced protozoal number in a dose‐dependent manner. The fibre degradation enzyme activity in rumen fluid increased by 17.7% with a concomitant 10% increase in volatile fatty acids (VFA); the protease activity was reduced by 23% with a corresponding reduction in rumen ammonia by 42%. In contrast, supplementing 3.0 g/kg of DOC has adverse effects on those measures compared with 1.2 g/kg of DOC. Defaunation was accompanied with substantial increases in the bacterial and fungal counts, but had no significant influences on VFI and the enzyme activity for starch, protein and pectin digestion, and small changes in fibre digestion enzymes and the total VFA compared with the control. A high correlation (r 2 = 0.82) was noted between VFI and the total activity of fibre digestion enzymes and VFA. It was proposed that fibre digestion rate in the rumen is a primary factor for determining VFI in sheep, and dietary supplementation of 1.2 g/kg of DOC could partially result in enhanced activity of fibre digestive enzyme in the rumen and increase VFI.
Highlights
Docusate (DOC), called as aerosol OT, is a surfactant
Compared to faunated and fauna-free animals, those reports showed ruminal protozoa had the effects on the digestion of dietary cellulose, starch and protein components, and defaunation alters the rumen ecosystem and tends to lower the rate of ruminal fermentation, the opposite result was reported in cattle on a high-grain diet (Nagaraja, Towne, & Beharka, 1992)
The primary findings of the present study are as follows: (a) ruminal protozoa could be partially moved by dietary supplementation of DOC; (b) supplementation of DOC could increase voluntary feed intake (VFI) in sheep; (c) the effect of DOC supplementation on VFI depended on the DOC dosage; and (d) an effective dose of DOC for increasing VFI was at 1.2 g/kg diet in this experiment
Summary
Docusate (DOC), called as aerosol OT, is a surfactant. Its sodium salt is water-soluble and can be used as a food additive, emulsifier, dispersant and wetting agent. Compared to faunated and fauna-free animals, those reports showed ruminal protozoa had the effects on the digestion of dietary cellulose, starch and protein components, and defaunation alters the rumen ecosystem and tends to lower the rate of ruminal fermentation, the opposite result was reported in cattle on a high-grain diet (Nagaraja, Towne, & Beharka, 1992). Because ruminal bacteria play a predominant role in fibre digestion, reducing protozoal number by partial defaunation could be accompanied with an increase in bacteria, digestion of dietary fibre, which could be significant in roughage-based diets. This hypothesis has been tested in our laboratory recently
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
