Impact of feeding saltbush (Atriplex sp.) on some mineral concentrations in the blood serum of lactating Awassi ewes

This study was conducted to assess mineral status in the blood serum of lactating Awassi ewes fed saltbush plants and concentrate rations. Twelve lactating Awassi ewes were randomly selected, and divided into two equal groups. Ewes in the first group (control) were fed the traditional ration usually fed to ewes at the station, consisting of concentrate and shredded straw of lentil (tibin). Ewes in the second group were fed amixture (1:1) of two saltbush species (Atriplex halimus and Atriplex nummularia) to replace roughage content in the experimental diet. Feeding saltbush to ewes lead to a decrease (P < 0.05) in Ca level in ewes after the fourth week of the experiment. Phosphorus level in the blood serum was higher (P < 0.05) in ewes fed saltbush than in ewes fed the traditional ration. However, blood serum of both groups contained lower Ca and P levels than normal. Although saltbush contained high levels of Cu, feeding saltbush did not lead to differences (P > 0.05) in Cu level in the blood serum of ewes in both groups. The high Mo content in saltbush resulted in an increase of Mo level in the blood serum of ewes fed saltbush compared to ewes fed the traditional ration. There was no difference (P > 0.05) in Zn level in the blood serum of both groups. Manganese level was higher (P < 0.05) in ewes fed saltbush than in ewes fed the traditional ration after the sixth week of the experiment. Selenium level in the blood serum (13.79–35.93 g/dl) was higher (P < 0.05) in ewes fed saltbush than in ewes fed the traditional ration (10.08–13.08 g/dl). Selenium levels of ewes in group 2 after the sixth week of the experiment were above than normal Se level (10–20 g/dl). The results of this experiment suggest that saltbush might lead to a decrease in Ca level and an increase in P, Mo and Mn levels in the blood serum. Selenium level in the blood serum of ewes fed saltbush might exceed normal levels and therefore special attention should be taken when feeding saltbush to lactating Awassi ewes for long periods. © 2003 Elsevier B.V. All rights reserved.