Table 3.

Effect of ground corn cob replacement on ruminal pH, ammonia-nitrogen (NH₃-N) and volatile fatty acid (VFA) concentrations in swamp buffalo

Items	Ground corn cob replacement (%)				SEM	Contrast1
	0	33	67	100		L	Q	C
pH	6.8	6.7	6.8	6.9	0.07	ns	ns	ns
NH3-N (mg/dl)	12.7	14.1	12.9	19.4	2.30	ns	ns	ns
Total VFA (mmol/L)	100.6	113.4	95.3	103.5	9.96	ns	ns	ns
	------------------------------mol/100 mol-------------------------
Acetate	68.7	62.2	68.8	69.7	2.04	ns	ns	ns
Propionate	19.8	23.6	19.5	16.7	1.22	*	*	ns
Butyrate	11.5	14.2	11.7	13.7	1.09	ns	Ns	ns
Acetate:propionate	3.5	2.6	3.5	4.8	1.67	*	*	ns
Protozoa (×105 cell/ml)	1.25	1.60	1.45	1.31	0.15	ns	ns	ns
Viable bacteria (CFU/ml)
Total (×1011)	8.4	11.0	10.9	11.3	2.0	ns	ns	ns
Cellulolytic (×109)	10.5	8.6	7.6	11.1	1.8	ns	ns	ns
Proteolytic (×108)	7.5	12.9	13.4	13.5	2.5	ns	ns	ns
Amylolytic (×108)	12.9	7.2	16.8	19.6	6.8	ns	ns	ns

¹L = Linear, Q = Quadratic, C = Cubic,

^*p<0.05, ns = p>0.05. SEM = Standard error of the mean. CFU = Colony forming unit.