Effects of lactulose supplementation on growth performance, nutrient digestibility, blood profiles, faecal microbial shedding, faecal score and faecal noxious gas emission in weanling pigs

Figures & data

Table 1. Feed compositions of control diet (as-fed basis).

Item	Phase 1 (days 1–14)	Phase 2 (days 15–42)
Ingredient (%)
Extruded corn	44.49	61.97
Soybean meal (48% CP)	21.20	27.80
Fish meal (66% CP, Brazil)	3.50	–
Soy oil	2.55	1.05
Lactose	8.30	–
Whey	10.00	5.00
MCP	–	–
DCP	1.5	1.5
Sugar	3.00	–
Plasma powder (AP 920)	3.00	–
L-Lys HCl (78%)	0.39	0.46
DL-Met (50%)	0.30	0.24
L-Thr (89%)	0.19	0.20
Choline chloride (25%)	0.10	0.10
Vitamin premix^a	0.10	0.10
Trace mineral premix^b	0.20	0.20
Limestone	0.98	1.13
Salt	0.20	0.25
Total	100.00	100.00
Calculated nutritional content
ME (kcal/kg)	3540	3410
CP (%)	20.00	19.00
Lys (%)	1.50	1.35
Met (%)	0.62	0.53
Met + Cys (%)	0.97	0.84
Ca (%)	0.95	0.90
Total P (%)	0.75	0.70
Avail P (%)	0.55	0.43
Crude fat (%)	5.02	3.98
Crude fibre (%)	1.87	2.45

^aProvided per kg of complete diet: 11,025 IU vitamin A; 1103 IU vitamin D₃; 44 IU vitamin E; 4.4 mg vitamin K; 8.3 mg riboflavin; 50 mg niacin; 4 mg thiamine; 29 mg d-pantothenic; 166 mg choline; 33 μgvitamin B₁₂.

^bProvided per kg of complete diet: 12 mg Cu (as CuSO₄•5H₂O); 85 mg Zn (as ZnSO₄); 8 mg Mn (as MnO₂); 0.28 mg I (as KI); 0.15 mgSe (as Na₂SeO₃•5H₂O).

Table 2. The effects of lactulose on growth performance in weanling pigs.^.

Items	NC	PC	L1	L2	SE
Phase 1 (days 1–14)
ADG (g)	340^b	371^a	373^a	358^ab	7
ADFI (g)	534	545	535	533	7
G:F	0.637^b	0.681^a	0.697^a	0.672^ab	0.013
Phase 2 (days 15–42)
ADG	562	588	589	570	10
ADFI	991^b	1051^a	1050^a	1022^ab	19
G:F	0.567	0.559	0.561	0.554	0.014
Overall (days 1–42)
ADG	488^b	516^a	517^a	499^ab	8
ADFI	839^b	882^a	878^a	859^ab	12
G:F	0.582	0.585	0.589	0.572	0.011

Note: Means in the same row with different superscripts differ (p < 0.05).

SE, standard error; NC, basal diet; PC, NC + 0.05% tiamulin; L1, NC + 0.1% lactulose; L2, NC + 0.2% lactulose.

Table 3. The effects of lactulose on digestibility and faecal moisture content in weanling pigs.^.

Items (%)	NC	PC	L1	L2	SE
Digestibility
2 weeks
DM	84.68	85.43	85.90	86.24	1.01
N	83.21	86.11	85.93	83.90	1.16
E	82.73^b	85.76^ab	86.59^a	85.74^ab	1.03
6 weeks
DM	83.13	84.08	84.05	84.01	1.05
N	81.77^b	85.35^a	85.28^a	82.59^ab	1.08
E	82.21	85.13	85.11	84.55	1.00
Faecal moisture content
2 weeks	70.47	70.11	68.99	69.54	1.74
6 weeks	70.61	70.41	69.56	68.95	0.76

Note: Means in the same row with different superscripts differ (p < 0.05).

SE, standard error; NC, basal diet; PC, NC + 0.05% tiamulin; L1, NC + 0.1% lactulose; L2, NC + 0.2% lactulose.

Table 4. The effects of lactulose on blood profiles in weanling pigs.

Items	NC	PC	L1	L2	SE
Lymphocyte (%)
2 weeks	39.43	43.63	45.43	44.86	4.27
6 weeks	62.40	58.44	59.64	65.89	3.98
RBC (10^6/µl)
2 weeks	6.09	6.04	6.13	6.03	0.14
6 weeks	6.61	6.57	6.67	6.93	0.21
WBC (10^3/µl)
2 weeks	19.33	21.44	20.63	20.97	2.47
6 weeks	19.44	15.56	15.27	17.17	1.57
Haptoglobin (mg/dL)
2 weeks	12.44	12.21	11.94	12.04	0.75
6 weeks	10.63	11.24	11.77	10.90	1.23

SE, standard error; NC, basal diet; PC, NC + 0.05% tiamulin; L1, NC + 0.1% lactulose; L2, NC + 0.2% lactulose.

Table 5. The effects of lactulose on faecal microflora and noxious gas emission in weanling pigs.

Items	NC	PC	L1	L2	SE
Faecal microflora (log10 cfu/g)
Lactobacillus	7.40^b	7.47^ab	7.60^a	7.48^ab	0.04
E. coli	6.43^a	6.36^ab	6.21^b	6.28^ab	0.06
Faecal score^a	3.23^a	3.19^ab	3.14^b	3.13^b	0.03
Faecal noxious gas emission (ppm)
NH3	28.13^a	23.50^ab	19.48^b	23.53^ab	3.00
Total mercaptans	4.35	4.05	3.95	3.95	0.12
H2S	3.98	3.88	3.58	3.55	0.23
Acetic acid	2.78	2.68	2.63	2.63	0.65

Note: Means in the same row with different superscripts differ (p < 0.05).

SE, standard error; NC, basal diet; PC, NC + 0.05% tiamulin; L1, NC + 0.1% lactulose; L2, NC + 0.2% lactulose.

^aFaecal scores were determined at 08:00 and 20:00 using the following faecal scoring system: 1 hard, dry pellet; 2 firm, formed stool; 3 soft, moist stool that retains shape; 4 soft, unformed stool that assumes shape of container; 5 watery liquid that can be poured.