Effect of Replacing Dietary Corn Silage with Hydroponic Barley Green Fodder on Holstein Dairy Cows Performance

Iranian Journal of Applied Animal Science (2021) 11(1), 47-57 47 Effect of Replacing Dietary Corn Silage with Hydroponic Barley Green Fodder on Holstein Dairy Cows Performance INTRODUCTION The dairy farm industry is one of the most important eco-nomical sectors of animal production in Iran, nevertheless the industry is challenged with the scarcity of fodder in most part of the year. Therefore, the farmers are continually looking for the ways to provide proper feeds and to lower feed cost and improve profitability (Kamalzadeh et al. 2008; Beldman et al. 2017). During the last decades there have been some arguments about the green fodder produc-tion in hydroponics system to compensate the forage supply for animals, using cereal grains seeds (Tudor et al. 2003; Fazaeli et al. 2012; Tranel, 2013; Naik et al. 2014). The hydroponics green fodder is produced from forage grains, mainly barley and oats, having high germination rate and grown for a short period of time (about one week) in a spe-cial chamber that provides the appropriate growing condi-tions (Al-Ajmi et al. 2009; Fazaeli et al. 2012). Develop-ment of hydroponic planting systems has provided the op-portunity for production of fresh forages from cereal grains in controlled growing chambers (Bustos et al. 2000; Gunasekaran et al. 2019). Depending on the type of grain, the forage mat reaches 15 to 20 cm high where production rate is about 4 to 8 kg of fresh forage equivalent to 0.70 to The objective of this study was to investigate the effect of inclusion of hydroponic barley green fodder (HBGF) in the diet on the performance of lactating cows. Eight Holstein cows (with daily milk yield of 31.15±2.75 kg and 83.23±12.46 days in milk) were assigned to 1 of 4 diets in a 4 × 4 latin square design. Control diet (I) consisting of 62% concentrates, 20% alfalfa hay, and 18% maize silage (dry matter (DM) basis), where in diets II, III and IV the maize silage was replaced by 20, 40 and 60% HBGF, DM basis, respectively. The green fodder yield was 869 g per kg planted seed (DM basis), showing a loss of 131 g DM. Dry matter intake was 23.20, 22.98, 22.67 and 22.65 kg/d on diets I, II, II and IV, respectively. The dietary HBGF level did not affect the average daily milk yield (27.38, 27.62, 26.41 and 27.22 kg/d), as well as the fat, protein and milk total solid yield. Feed efficiency (milk yield per kg DM intake) was 1.26, 1.27, 1.28 and 1.31 which did not significantly affected by the treatments. Finally, inclusion of HBGF up to 60% of maize silage portion, equal to 10.5% of total diet (DM basis), did not affect the performance of lactating cows when compared with maize silage. However, the biomass yield (DM basis) of hydroponic barley green fodder per kg seed grain was lower than that of the initial grain which would increase the cost of feeding.