The Effect of Sorghum Stalk Silage Supplementation on Milk Production and Composition of Indigenous Milking Cows in the Peak Dry Season at ShoaRobit, Ethiopia

Abstract

In the semi-arid areas of Ethiopia, utilization of sorghum stalk as feed has shown significant growth annually due to the expansion of  sorghum production. Sorghum stalk is the dominant crop residue conserved in the study area and farmers mostly rely on it to feed their  draught oxen and milking cows during the dry season. Sorghum stalk is conserved in loose form in open air till it lasts without shade.  Such practice leads to the loss of nutritive quality due to weathering and fermentation exposures. The use of concentrates and improved  forages is nonexistence due to high cost and unavailability, leaving the poorly conserved crop residues as the only source of feed to  sustain productivity. This study aimed at evaluating the total yield and composition of milk produced by lactating cows supplemented  with sorghum silage in the dry season. Twenty-two indigenous milking cows of volunteer farmers were allocated into two treatments  (silage supplemented and un-supplemented/farmers practice). Milk yield was higher (P < 0.05) for cows fed with silage than the un- supplemented group. Cows that are not supplemented with silage had poor body condition, as opposed to lactating cows fed silage.  Cows in the supplemented group produced on average 2.26 liters of milk per day, which was significantly higher (P < 0.05) than the un- supplemented group (1.16 liters per day). The silage contained better protein content (6.59%) as compared to the dry stalk (4.38). Milk fat,  protein, solid-not-fat and density were not affected by the treatments (P > 0.05). The result indicates that conservation of sorghum  stalk immediately after grain harvest in the form of silage improves milk yield.