Evaluation of jojoba meal as a protein source for Sheep [electronic resource].

Includes reference.

The present study was conducted to investigate the effect of replacing cotton seed meal (CSM) by,jojoba meal (JJM) on the digestibility, ruminal activity and growth performance of lambs. Twenty Rahmany growing ram lambs, weighing 37± 1.37 kg, were used for 100 days. Animals were divided into four similar groups and each received one of the four rations. Four concentrate mixtures were formulated to replace JJM at 0 % (ration 1),33 % (ration 2),50 % (ration 3) and 100 % (ration 4) of CSM. The offered ration was the tested concentrate mixture (70 %) and wheat straw (30 %). Digestibility trials and ruminal fermentation were conducted. The chemical analysis of the experimental rations did not affected by replacement of CSM by JJM. The digestibility coefficient of dry matter (DM) was ranged from 61.60 to 74.60 %, and there were significant differences (P<0.05) between the rations. The same trend was observed with the digestibility of organic matter (OM), crude protein (CP), ether extract (EE) and nitrogen free extract (NFE). The replacement of CSM by JJM till 50 % of it enhanced the digestibility coefficients of DM, OM, CP, EE and NFE. As for CF digestibility, it decreased by increasing the level of replacement. Total digestible nutrients (TDN) and digestible crude protein (DCP) were increased with replacing CSM by JJM till 50% of it. There was (P<0.05) significantly reduction in dry matter intake (DMI) when JJM was replaced in the rations. There were no significant (P>0.05) differences in rumen pH among all rations for all sampling times. The highest value of ammonia nitrogen (NH₃-N) was 15.57 mg/100 ml rumen liquor (RL) for ration 1, and the lowest value was 12.12 mg/100 ml RL for ration 3. The mean values of total volatile fatty acids (VFA) were 10.89,8.69,7.49 and 7.75 meq/100 ml R.L. for rations 1,2,3 and 4, respectively. The average daily gains (ADG) of lambs were 0.136, 0.126, 0.079 and 0.064 kg/h/d, respectively. The feed conversion by lambs was 8.69, 6.28, 10.05 and 13.23 kg DMI/kg gain. The economical efficiency was 0.09,0.12,0.08 and 0.06 for rations 1,2,3 and 4, respectively. The current study showed that the replacement of CSM by 33 % of JJM is better than the other rations regarding feed conversion and economic efficiency to increase feed resources. The more studies are needed to improve the nutritive value ofJJM to use it as a protein source in ruminants' rations.

Summary in Arabic.

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