Effects of replacing soybean meal with detoxified Jatropha curcas kernel meal in the diet on growth performance and histopathological parameters of growing pigs

• A certain amount of detoxified Jatropha curcas kernel meal added in diet has a positive effect on performance of growing pigs.
• Detoxified Jatropha curcas kernel meal could replace 30% soybean meal in growing pig diet.
• The tolerance of phorbol esters concentration of growing pigs was 5.5 mg/kg diet.

The study was conducted to investigate the effects of replacing soybean meal (SBM) with different levels of detoxified Jatropha curcas kernel meal (DJKM) in growing pig diets on growth performance, haemato-immunological and histopathological parameters. A total of 144 pigs (Duroc × Landrace × Yorkshire) with initial body weight of (20.47 ± 1.44) kg, were randomly allocated to 6 dietary treatments with 6 replications per treatment and 4 pigs per replication for a period of 79 days. The 6 diets (D1, D2, D3, D4, D5 and D6) were formulated using DJKM to replace 0%, 15%, 30%, 45%, 60% and 75% SBM protein and contained phorbol esters (PEs) of 0, 2.75, 5.50, 8.25, 11.00, 13.75 mg/kg diets. At d 29, pigs in 3 replicates in D6 treatment were offered D1 diet (expressed as D6 + D1) to examine the residual effect of diet D6 in a re-feeding trial. From d 1 to 79 of experimental period, pigs fed diets D4, D5 and D6 had significantly lower average daily gain, average daily feed intake and gain-to-feed ratio than those fed diet D1 (P<0.05). However, the negative effect of diet D6 was disappeared after two weeks of feeding diet D1 in the re-feeding trial. In addition, pigs offered diets D5 and D6 had significantly higher activities of serum alkaline phosphatase, but lower serum alanine transaminase when compared with pigs given diet D1 (P<0.05). Moreover, pathological alterations in liver were observed in pigs fed diets D3, D4, D5 and D6 relative to D1. There results indicate that DJKM could be used to replace SBM protein up to 30% with no detrimental impacts on growth performance, haemato-immunological and pathological parameters in growing pig diet.