Effects of treating barley grain with lactic acid on growth performance and blood parameters of male Holstein pre-weaned calves

This study was conducted to evaluate the effects of treating ground barley grain with lactic acid (LA) in starter diets on feed intake, average daily gain,feed efficiency, nutrient digestibility, skeletal growth, and blood metabolites of pre-weaned dairy calves. Thirty male Holstein calves with averageinitial body weight of 45.06±2.25 were randomly allocated to one of the 3 treatments. Starter containing 41% ground barley grain from day 4 to 65 ofbirth. Experimental treatments include: 1) diet containing treated barley in tap water (No LA), 2) diet containing treated barley in 0.5% LA solution,and 3) diet containing treated barley with 1% LA solution. Feed intake was recorded daily. Body weight and skeletal growth measures were recordedon day 4, day 35, and day 56. Calves blood samples were collected on day 4, 35, and 65. Total tract dry matter digestibility and feed efficiency weregreater in calves fed diet containing lactic acid treated barley (P ≤0.05). No effects on dry matter intake, average daily gain, and blood metabolites wasobserved. At day 35 of the experiment the withers height and body length were greater in calves received LA-treated barely (P ≤0.05). It seems thattreating barley grain with lactic acid decreased starch digestion in the rumen and increased starch flow to the small intestine; accordingly, feedefficiency was improved. Using higher levels of lactic acid may have a positive effect on calf performance.