Table 1

Table 2.
Effect of protein degradability and supplementation frequency on ruminants consuming low-quality forage

								P-Value^b
	Treatment^a							Con vs	H vs	L	Q
Item	CON	HD	H3D	H6D	LD	L3D	L6D	Supp	L	SF	SF
Lambs (36 kg)
OM Intake, g/kg BW	20.2	24.0	22.7	22.3	25.6	24.5	21.3	0.005	0.29	0.004	0.69
Total Tract OM Dig., %	54.0	62.4	61.9	60.4	60.9	63.2	63.2	<0.001	0.28	0.87	0.34
N balance, g/kg BW	-0.009	0.101	0.088	0.094	0.098	0.094	0.068	<0.001	0.25	0.04	0.94
Digested N retained, %^c	-16.3	35.3	27.7	29.6	31.2	25.8	24.0	<0.001	0.54	0.41	0.63

Steers (264 kg)
OM intake, g/kg BW	20.7	24.1	25.6	22.7	23.1	24.4	22.8	0.007	0.33	0.34	0.03
Total Tract OM Dig., %	53.3	61.3	58.1	58.0	59.3	59.0	58.7	0.001	0.87	0.11	0.46
Bacterial N Production, g/kg BW	0.237	0.410	0.441	0.419	0.309	0.413	0.328	0.004	0.04	0.73	0.09
Bacterial Efficiency^d	20.0	28.9	29.0	32.0	23.2	28.8	24.0	0.04	0.09	0.52	0.48

Cows
Initial body condition score	5.06	5.00	4.98	4.96	4.91	4.91	4.90
BCS change	0.12	0.65	0.56	0.50	0.63	0.59	0.65	<0.001	0.48	0.50	0.68

^a CON = control; HD = high rumen degradable protein every day; H3D = high rumen degradable protein every third day; H6D = high rumen degradable protein every sixth day; LD = low rumen degradable intake protein every day; L3D = low rumen degradable protein every third day; L6D = low rumen degradable protein every sixth day.

^b Con vs Supp = control vs supplemented treatments; H vs L = high rumen degradable protein vs low rumen degradable protein; L SF = linear effect of supplementation frequency (SF); Q SF = quadratic effect of SF.

^c Calculated as (Daily N retention, g/kg BW / Daily N digested, g/kg BW) ´ 100.

^d Calculated as g bacterial nitrogen/kg of OM truly digested in the rumen.

Cows