Growth Performance and Some Body Muscles Measurements of Zaraiby Goats Feed Ration with Adding Ordinary or Nano Cobalt

Twelve local Zaraiby goats with average live body weight of 10.71±0.23 kg (5-6 months). Animals were divided into three comparable groups. Goats in first group were fed without supplement (control group) or supplemented with 25% ordinary cobalt and 25% nanocobalt from cobalt requirements (NRC, 1985). The results showed that no significant difference (P>0.05) among experimental groups for DMI and CPI values. However, there was a highest significant difference (P<0.05) in average daily gain, total gain, and feed efficiency (kg gain/ kg DMI) for nanocobalt group. Nutrients digestibility values as DM, CP, CF, NFC, ADF, NDF, cellulose and hemicellulose in addition to percentage of TDN in nanocobalt treatment were higher significantly than those others groups. But the ratio of nitrogen balance in goats' diet with nanocobalt group was less than that using ordinary cobalt and control group. While the DE (Mcal/Kg DMI) ratio was no significant differences observed among groups. Rumen pH and TVFA’s values after 3 and 6 hours of feeding, the control and the ordinary cobalt groups increased (P<0.05) more than the nanocobalt group. After 3hrs, adding nanocobalt has lower significant values for NH 3 -N than those others. Where, the control group recorded the lowest value. No significant (P>0.05) differences were observed at 0, 3and 6 hrs. after feeding for all blood parameters. There was a slight increase for most of body measurements with nanocobalt supplement. It could be concluded that adding nanocobalt for goats' rations enhanced growth performance, digestibility coefficients, rumen parameters and slightly body measurements without any diverse effect on animals' health.