ABESTRACT
Forty mature healthy Barki ewes at late pregnancy aged 3- 4 years and had average LBW 51.5±0.46 kg were used in this experiment. Ewes were randomly divided into 4 similar groups (10 each), to evaluate the viability of complete replacement of Berseem hay in the diet by leaves and stems of Acacia Niloitica, Atriplex Nummularia and Cassava Manihotesculenta shrubs, as well as to study their effects on the immunity indices of ewes and their lambs, blood biochemical parameters, blood pictures and mortality rates of new born lambs. All animals kept in a semi-open shaded yard and kept under the same managerial condition during the experimental period. The 1st group (G1) was fed the control diet consisted of 40 % concentrate feed mixture (CFM), plus 60% Berseem hay (BH), while the 2nd, 3rd and 4th groups, BH was replaced by leaves and stems of Acacia (G2), Atriplex (G3) or Cassava (G4), respectively.
Immunoglobulin's levels (IgG and IgM) were estimated in ewes colostrum and serum of their offspring at 2, 6, 12 and 24 h post-partum. Meanwhile, blood pictures in whole blood, as well as, levels of glucose, total protein, albumin, triglycerides, total cholesterol and Urea-N assayed in plasma of ewes and offspring during suckling period. In addition, mortality rate of newborn lambs were calculated.
Results show that, IgG and IgM levels in ewes colostrum and lambs serum tended to decrease during the first 24 hours post-partum, showing significant (P<0.05) lowest levels at 24 h post- partum. Immunoglobulin (IgG and IgM) levels in colostrum were significantly (P<0.05) affected by replacing Berseem hay with salt plants, where IgG and IgM concentrations were higher in all treated groups (G2, G3 and G4) comparing to control. Moreover, ewes in group G4 fed on Cassava showed higher colostrum IgG and IgM concentrations than other treated groups. Levels of IgG in lambs serum were significantly (P<0.05) the highest in G4 (22.64 mg/mL) fed on Cassava compared with control and other treatments groups, G1, G3 and G2 (21.71, 17.26 and 16.85, respectively). Moreover, Acacia, Atriplex and Cassava based diets enhanced (P<0.05) the concentration of lamb serum IgM compared to control. Cassava, diet (G4) significantly (P<0.05) improved hematological parameters of ewes compared to Acacia (G2), Atriplex (G3) and control (G1) groups. Groups fed either Acacia or Atriplex were within the same range of blood picture of the control group. Cassava group (G4) had greater percentage of viable lambs till weaning compared with either G2 or G3.
Replacement of Berseem hay in lactating Barki ewes' diets in Egyptian Northern Coast with Cassava, Atriplex or Acacia plants is recommended, as they did not have negative impact on the blood biochemical parameters of lactating ewes and their lambs, as well as, lambs mortality rates.