The effect of diet on performance, digestibility, blood composition and intestinal microflora of weaned pigs.

Good evaluation variables are needed to study postweaning lag in early weaned pigs. In this study, performance, digestibility, concentration of blood components and aerobic fecal microflora under different dietary regimens from weaning at 3 wk of age to 35 d of age are reported. Treatment 1 (T1) consisted of a corn-soybean meal starter diet. Pigs in treatment 2 (T2) received a steamed, rolled oat groats-casein starter diet. Pigs in treatment 1 and 2 were weaned at 3 wk of age while those in treatment 3 remained with the sow. Treatment 1 pigs had lower average daily gains for the 2-wk trial as compared with T2 pigs (P less than .05). Three of the four animals consuming the corn-soybean meal diet were observed to have diarrhea during the experiment as compared with an occasional loose stool from the pigs fed oats-casein. There were no significant differences in digestibility of dry matter, crude protein or ether extract among pigs in T1 and T2. Digestibilities of ash and crude fiber were higher (P less than .05) in T1 pigs, while there was an increase (P less than .05) in digestibility of N-free extract by pigs in T2. Serum protein, Na, CO2 and blood hematocrit were not significantly different among treatments. Blood chloride was higher, whereas glucose was lower for pigs in T1 and T2 than T3 (P less than .05). Blood urea N was higher for pigs in T1 as compared with pigs in T2 or T3. Potassium was higher (P less than .05) for pigs in T1 as compared with those in T2 or T3.(ABSTRACT TRUNCATED AT 250 WORDS)