Fat source effects on finishing steer digestion and metabolism

A replicated 3 x 3 Latin square design was used to explore the effects of fat source (none vs 3.5% soybean oil soapstock or animal tallow) when fed with high (1.0%) calcium on digestion and metabolism of a finishing diet by steers. Adding fat did not affect site or extent of starch or dry matter digestion. A net synthesis of long chain fatty acids occurred in the rumen. Feeding fat tended (P=.ll) to depress bacterial N flowing at the duodenum but did not affect nonbacterial N or total N