Department of Animal Science, Faculty of Agriculture, Urmia University, Urmia, Iran
This study was conducted to determine the chemical composition and nutritive value of sunflower residues silage (SRS) and effects of its substitution with alfalfa hay and corn silage on lactation performance, feed intake, nutrient digestibility and some blood parameters of Mohabadi dairy goats. Four experimental diets were formulated to gradually replace alfalfa hay and corn silage with SRS as follows: Control (no inclusion of SRS, group 1) and groups 2 to 4, representing 15, 30 and 45.00% replacement of common forages in the diet with SRS, respectively. Sixteen multiparous dairy goats weighing 60.00 ± 3.00 were divided into two 4 × 4 latin square design. Ensiling was being able to increase crude protein content, reduce neutral detergent fiber and increase acid detergent lignin in sunflower residues. Daily dry matter (DM) intake and DM and organic matter (OM) digestibility decreased with increasing levels of SRS in the diet. The highest and the lowest digestibility coefficients belonged to 30 and 45.00% embedment levels, respectively. Milk yield decreased with increasing levels of SRS and differences were statistically significant compared to the highest substitution level. Milk composition was similar among diets, but daily production of milk decreased in higher substation levels. Statistically significant differences were found in serum low-density lipoproteins (LDL) concentrations between treatments and LDL levels decreased as dietary levels of SRS increased. According to these results, SRS is an acceptable feed for dairy goats and common dietary forages can be replaced up to 30.00% with SRS without negative effects on milk yield and composition.