Mineral profile, inmunoglobulins and antioxidant activity in culls cows fed DDGS
The objective was to evaluate the effect of four levels of Distillery Dry Grains (DDGS) in the diet of cull beef cows on body weight (BW) and average daily gain (ADG) every 15 d and the mineral profile ( Zn, Mn and Cu ) and immunoglobulins in blood serum, and the antioxidant activity (AA) in blood plasma (d 0 and d60). Thirty five mature cows of different genotypes with an average live weight of 350±40 kg were randomly divided into four treatments with different levels of DDGS: T1 (Control, 0 %, n= 9), T2 (5.7 %, n= 9), T3 (11,23 %, n= 8) and T4 (16.45 %, n = 9). A completely randomized design with treatment and time of sampling as fixed effects was used. Data was analyzed with the GLM of SAS. For the multiple comparisons of means a Tukey's test was used. The BW and ADG were similar (P>0.05) between treatments. Serum levels of Zn, Cu, and Mn between treatments did not differ (P> 0.05). During the feeding period the serum levels of Zn and Cu were similar (P>0.05). However, levels of Mn were higher (P< 0.05) at d 0 than at d 60 (1.69±0.11 µmol/L vs 1.36±0.11 µmol/L, respectively). The AA and immunoglobulins were similar (P>0.05) between treatments at d 60, but were different (P< 0.05) at d 0 (5.74±0.32 g *100 mL 1) vs d 60 (8.12±0.33 g *100 mL 1) of the feeding period. It was concluded that the inclusion of DDG’s in the diet of cull beef cows did not affect the ADG, the mineral profile and the AA. However, Mn concentration was reduced and immunoglobulin increased during the 60 d feeding period.
Cull cows, antioxidant activity, mineral profile, Immunoglobulin