Thirty weaned crossbred (Large White York Shire × Desi) piglets were randomly allotted to five dietary treatments (T1, T2, T3, T4 and T5), each consisted of 12 animals (6 barrows and 6 gilts). First treatment (T1) served as control and others were experimental groups. Diet 1 (T1) was formulated with maize (54%), wheat bran (10%), groundnut cake (17%), DORP (10%), fish meal (6%), mineral mixture and vitamin supplements. Diets 2 (T2), 3 (T3), 4 (T4) and 5 (T5) were formulated using paddy instead of maize at 25, 50, 75 and 100 percent. Age at 1st estrous was found significantly higher (P<0.05) in group T5 as compared to T1 group. Age at 1 st service was found significantly higher (P<0.05) in gilts maintained on T4 and T5 diets than control. In barrows there was no significant (P>0.05) difference in fasting weight, weight after bleeding and evisceration weight between T1, T2 and T3 groups, however these parameters were significantly lower in T4 and T5 groups as compared to control. Statistically there was no significant (P>0.05) difference in fasting weight, weight after bleeding and evisceration weight of gilts of T1, T2, T3 and T4 groups, however it was significantly (P<0.05) lower in T5 group as compared to control. The dressing percentage of boars and dressing percentage, carcass length, backfat thickness and loin eye area in gilts was significantly (P<0.05) lower in T3, T4 and T5 groups as compared to T1 group, however it did not differ significantly between T1 and T2 groups. In both barrows and gilts, statistically there was no significant (P>0.05) difference in average percent weight of shoulder between T2 and T3 groups, however it was significantly (P<0.05) higher in T4 and T5 group as compared to control. In barrows, average percent weight of bacon and ham was significantly (P<0.05) lower in T4 and T5 groups as compared to control, however showing no significant difference in T1, T2 and T3 groups. Average percent weight of loin shows no significant (P>0.05) difference in T1 and T2 group; however is significantly (P<0.05) higher T3, T4, and T5 groups as compared to control. There was no significant difference in the average percent weight of rib chop and undercut among control and treatment groups. In gilts the percent weight of bacon and ham was significantly (P<0.05) lower in T2, T3, T4, and T5 groups as compared to control. There was no significant difference in the percent weight of rib chop and undercut between T1 and T2 groups, however it is significantly lower in T3, T4 and T5 groups as compared to control. Total cost of production was higher at higher level of replacement of maize with paddy in pigs.
