Influence of sorghum inclusion level on performance of growing local Mukota, Large White and their F1 crossbred pigs in Zimbabwe

A study was conducted to determine the effect of level of substitution of Red Swazi A sorghum variety (RSA) for maize on average feed intake (ADFI), average daily body weight gain (ADG) and feed conversion ratio (FCR), hot carcass mass (HCM), cold dressed mass (CDM), drip loss (DL) and backfat thickness (BF) in Large White (LW), Mukota and F1 crossbred pigs. Twelve pigs of each breed were randomly assigned to diets that contained 0, 200, 400 and 600 g/kg of RSA, and similar levels of energy and crude protein. The pigs were kept for 14 weeks. There was a linear decrease in ADG in the crossbred pigs as the sorghum level increased (P < 0.05). In the LW pigs, no linear or quadratic relationships existed in ADG. The ADG in the Large White and crossbred pigs was 0.69 and 0.61 kg, respectively. In Mukota pigs, however, there was a linear increase (P < 0.05) in ADG with sorghum inclusion level. The least square mean ADG for Mukota pigs was 0.34. The FCR increased (P < 0.05) in both LW and crossbred pigs as sorghum level increased, but no statistically significant change was observed in the Mukota. The least square mean FCR were 4.2, 3.3 and 3.7 for Mukota, LW and crossbred pigs, respectively. The respective DL values were 0.01, 0.02 and 0.03 for the Mukota, LW and crossbred pigs. The BF values were 8.8, 14.5 and 14.0 for Mukota, LW and crossbred pigs, respectively. These findings suggest that Mukota pigs could utilise diets containing high levels of red sorghum better than either the LW or crossbred pigs. Mukota pigs, which are indigenous and adapted to sub-tropical environmental conditions, can therefore be recommended for use in dry areas that are suitable for sorghum production to achieve sustainable pig production.