2. Materials and Methods
2.1 Experimental Animals and Diets
The experimental protocols used in this study were
approved by the Sichuan Agricultural University
Institutional Animal Care and Use Committee. A total
of 24 crossbred (PIC variety) finishing pigs (average
initial body weight was 60.05±1.24 kg, 12 gilts and 12
barrows) were used. The pigs were assigned randomly
to one of the three dietary groups, with four pens/group
(two pigs/pen, per pen: one gilt and one barrow). Each
pen was equipped with a feeder and nipple water to
allow the pigs free access to feeds and drinking water.
Temperature (22 ℃ to 26 ℃) and a cycle of 16 h light:
8 h dark were maintained in the mechanically
ventilated room. The pigs were fed a basal diet
containing 0 (control), 70 or 140 mg/kg CS (28%
cysteamine hydrochloride. 70, the suitable quantity;
140, excess of the safety dosage; the quantity had been
determined through growth performance, cysteamine
dose-response and gastrointestinal tract relationship,
data not shown). The basal diet met or exceeded
nutrient requirements recommended by the National
Research Council (1998) for pigs (Table 1) [14].
Pig weight and feed intake were measured weekly.
The experimental feeding period lasted for 47 days.