The effects of feed restriction severity on compensatory growth of goat kids in Bushehr Province Iran

Abstract

In order to study the effects of the different severity of feed restriction and consequence compensatory growth on carcass and diet digestibility of goats and possibility use of this strategy in alternate droughts and feeding cost reduction, 40 black native goat kids (about 7 to 8 month old) were used. All goat kids were divided randomly into 4 groups in a CRD plan: 1) Control 2) M=Maintenance 3) SM1=Sub-maintenance 1 and 4) SM2=Sub-maintenance 2 with the same feed of control group in the re-alimentation period. Each group had 10 replicates (goats). Control group were fed with a ration supporting 50 gr of daily weight gain and restricted groups were fed with a maintenance ration. The duration of restriction was considered 75 days and after that feeding with controlled concentrate and ad libitum straw feeding started until the average of restricted goats approached that of control. The results showed that there was not significant difference in carcass DM and gross energy (P>0.05). Significant increase in carcass ash of M group rather than other groups was observed (P<0.05). Ether Extract of control (39.28) and SM2 (39.64) were significantly increased (P<0.05). Feed restriction severity significantly decreased digestibility of DM, OM, CP and gross energy (P<0.05) whereas after re-feeding (compensatory growth), there was not significant effect in DM, OM, CP, Ether Extract and gross energy (P>0.05). There was significant difference in pelvic fat weight (P=0.06) and percentage of pelvic fat/EBW (P=0.07).