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)

The effect of diet on fecal moisture, osmolarity of fecal extracts, products of bacterial fermentation and loss of minerals in feces of weaned pigs.

Litters of pigs were allotted to one of three dietary treatments. Treatment 1 (T1) consisted of a corn-soybean meal starter diet. Pigs fed treatment 2 (T2) received a steamed, rolled oat groats-casein diet and pigs in treatment 3 (T3) remained with the sow. Four pigs/treatment were used to investigate the difference in performance and the cause of post-weaning diarrhea associated with early weaning of pigs at 4 wk of age to a starter diet. Fecal moisture, osmolarity, acetic acid, lactic acid and glucose contents were all good indicators of dietary differences because of treatment X age interactions. These variables increased faster in fecal extracts from pigs fed the corn-soybean meal diet. Lactic acid, volatile fatty acid (VFA) levels, glucose and pH values were indicative of a more active bacterial fermentation in pigs receiving T1 than in those receiving T2 or pigs remaining with the sow (T3). Excess minerals appear to contribute significantly to the osmolarity of fecal material. Of the anions, lactate was the main contributor to the osmolarity of feces of T1 pigs, followed by P, VFA, of which acetic acid contributed 70%, and Cl. The main cations were K, Na and Ca. In T2, P was the main anion, followed by lactate, VFA and Cl, while the main cations were Na, K and Ca. Minerals seemed to be the major osmotic particles in fecal extracts of pigs remaining with the sow. Phosphorus was the major anionic contributor to osmolarity, followed by VFA, Cl and lactic acid. Potassium was the major cation, followed by Na and Ca.(ABSTRACT TRUNCATED AT 250 WORDS)