The effects of bentonite on rumen protozoal population and rumen fluid characteristics of sheep fed palm kernel cake

• Main Authors: Abdullah, Norhani, H., Hanita, Ho, Yin Wan, Kudo, Hiroshi, Jalaludin, S., Ivan, Michael
• Format: Article
• Language: English
• Published: Asian-Australasian Association of Animal Production Societies 1995
• Online Access: http://psasir.upm.edu.my/id/eprint/50016/1/The%20effects%20of%20bentonite%20on%20rumen%20protozoal%20population%20and%20rumen%20fluid%20characteristics%20of%20sheep%20fed%20palm%20kernel%20cake.pdf; http://psasir.upm.edu.my/id/eprint/50016/; http://www.ajas.info/journal/view.php?number=18972

The effects of bentonite (B) on rumen protozoal population and rumen fluid characteristics of sheep fed palm kernel cake (PKC) were studied for a period of 21 days. Two groups, each comprising two sheep were fed either PKC or PKC + B ad libitum. A third group was left at pasture. Rumen fluid was sampled through a rumen cannula three times daily from all animals. Palm kernel cake contained 16% crude protein, 1% crude fat and high amounts of copper, zinc, iron and manganese. Protozoal population in the rumen fluid decreased significantly (p<0.05) after the onset of feeding PKC or PKC + B. However, sheep given bentonite supplementation at 2% of the dietary dry matter, maintained higher protozoal densities (15 x 104/ml) when compared to animals fed only PKC (8 x 104/ml). With both diets, the protozoa were mainly of the small entodinia species. Animals at pasture had higher protozoal population (47x 104/ml) with varying species of entodiniomorphids and holotrichs. Rumen fluid pH and ammonia concentration was significantly (p<0.05) higher in animals at pasture compared to animals fed PKC or PKC + B. Volatile fatty acid concentration was significantly (p<0.05) lower in animals fed PKC when compared to animals at pasture. There was a shift in fermentation pattern in animals fed PKC or PKC + B towards a lower acetate; and higher propionate, isovalerate and valerate. Studies in vitro also showed the positive effect of bentonite on protozoal numbers.