Evaluation of EM-2 as Biological Crop Residue Treatment Option Targeted for Feeding Crossbred Dairy Cattle

Abstract

A study was conducted at Holetta Agricultural Research Center with the objective to evaluate the effect of ensiling crop residues (wheat,  barley and oat) with extended EM solution (EM2) on the nutritive value, in-vivo digestibility coefficients and animal response. Accordingly,  crude protein (CP), DOMD (digestible organic matter in the dry matter), EME (estimated metabolizable energy), total ash,  NDF (Neutral detergent fiber), ADF (Acid detergent fibre) and lignin (P<0.05) were significantly (P<0.05) improved by EM2 treatment as  compared to the untreated straws. On the contrary, DM (dry matter) & OM (Organic matter) losses as a result of EM-2 treatment were  substantial (P<0.05) for all the three residues under investigation. Barely straw was found to be higher (P<0.05) for all chemical  compositions and in-vitro digestibility values except DM & OM. The rate of change calculated as percentage differences over the original  untreated residue was higher for the relatively inferior quality wheat straw. From the result of the first laboratory trial, application of EM2  at the rate of 1 liter per kg straw mass have been seen to adequately improve chemical compositions and in-vitro digestibility of cereal  residues. In the second trial were mid lactating Boran-Fresian crossbreds cows have been fed with either ad libtum EM2 treated or  untreated barley straw and supplemented with different levels of on-station formulated dairy concentrate @ 0.3, 0.5 and 0.7 kg/liter of  milk daily intake of EM2 treated barley straw was significantly improved (P<0.05) for all experimental cows other than those on the  control diet. Daily total DM intake followed same trend as for the basal feed intake. Among experimental cows receiving treated straw  basal diet cows on dietary T3 consumed superiorly higher (P<0.05) daily total feed intake. In general, daily intakes for all nutrients under  considerations were higher (P<0.05) for cows fed the EM2 treated barley straw as a basal diet on a daily basis. While maximum daily  nutrient intake (P<0.05) was recorded for cows receiving T3 lower intakes (P<0.05) were recorded for cows that have received the control  diet. There was no difference (P>0.05) for apparent digestibility of DM & OM. Higher digestibility coefficients of CP, NDF and ADF were  recorded for cows maintained under dietary T3. Daily milk yield and compositions except milk lactose and total solids were statistically  different (P<0.05) among cows that were fed with the treated barley straw diet and when same cows were compared with those that have  been fed with the untreated barley straw basal diet. Higher milk (P<0.05) was, however, produced by the cows receiving dietary T3.  However, due to high cost of straw treatment compared to cows on the control diet the gross and net profit obtained from intervention  treatments were marginal.