The effects of incorporating sprouted barley in diets of high-yielding dairy cows on production, efficiency, and nutrient digestibility

Abstract

The sprouted system is the process of growing grains hydroponically in trays. Recently, there has been interest in using sprouted grains as feed for ruminants. The objective of this study was to determine how including sprouted barley in dairy cow rations affects performance, nutrient digestibility, and efficiency. Forty-two mid-lactation Israeli Holstein dairy cows were divided into two treatment groups (n = 21) and fed for 12 weeks: (1) Control (CTL) – a typical milking cow ration contained 38.9% forage (DM basis) and (2) Sprouted Barley (SB) – a diet contained 33.7% forage, and 11.5% (DM basis) SB. Diets were fed as a total mixed ration. Milk yields and BW were recorded daily, and milk samples were taken for milk solid concentration. Rumen and faecal samples were taken for volatile fatty acid and digestibility measurements, respectively, and blood samples were taken for blood metabolite analysis. Milk yield was 4.1% higher (45.7 and 43.9 kg/d, respectively; P < 0.001) in the SB cows. Milk fat concentrations and yields were lower in the SB cows than in the CTL cows (3.82 and 4.10%, P < 0.001, and 1.69 and 1.77 kg/d, P = 0.04, respectively). Milk protein concentration was higher in the SB cows with no difference in protein yield, and the milk urea nitrogen was 17.0% lower in the SB cows (P < 0.001). The 4% fat-corrected and energy-corrected milk yields did not differ between treatments, and the DM intake (DMI) tended to be higher in the CTL (P = 0.08). The milk-to-DMI ratio was 6.3% higher in the SB cows (P < 0.001), with no differences in other efficiency calculations. The rumen ammonia concentration was 21% lower in the SB cows (P = 0.006), and rumen acetate, propionate, and total volatile fatty acids were higher in the CTL cows. Apparent total tract digestibility of DM, organic matter, and CP was higher in the SB cows (P = 0.003) and tended to be higher for NDF (P = 0.10). Lower blood levels in triglycerides, urea, and cholesterol were observed in the SB cows (P = 0.04). In summary, sprouted barley is a potential feedstuff; however, further research is needed to determine an accurate nutritional value of sprouted barley and to fine-tune the optimal amount in the high-yielding dairy cow ration. This essential knowledge is required to reliably determine the economic viability of using sprouts in ruminants’ nutrition.