Evaluation of the Nutritive Value and Digestibility of Sprouted Barley as Feed for Growing Lambs: In Vivo and In Vitro Studies

SIMPLE SUMMARY: Sprouted barley has recently been used in animal feed, but studies on its nutritional and digestibility values for growing lambs are very limited, especially when compared with traditional forages. However, the aim of the current research is to determine the practical level and nutritional properties of sprouted barley as a replacement for the traditional feed for growing lambs by ascertaining its efficacy of performance, nutritional value, digestibility, and fermentation characteristics in vivo and in vitro. The current research helps both workers and researchers to determine the level and the most effective way to utilize sprouted barley as an alternative strategy to traditional feeding systems. In conclusion, sprouted barley with traditional feed improves digestibility and fermentation characteristics. Further studies are needed to increase nutrient requirements for optimal lamb growth performance. ABSTRACT: The main objective of this study was to investigate the effects of freshly sprouted barley on the growth of lambs, in addition to its nutritional value and digestibility. In addition, sprouted barley digestibility and rumen fermentation were studied in vitro on a dry matter (DM) basis. A total of 45 three-month-old Awassi lambs were randomly assigned to five treatments of sprouted barley (0, 25, 50, 75, 100%) diets. Bodyweight, weight gain, feed intake and feed efficiency were recorded every two weeks. Nutrient analyses were performed on feed, faecal, and urine samples. DM and non-fibrous carbohydrates were measured. Digestibility of DM, organic matter (OM), and neutral detergent fiber (NDF), as well as gas production, pH value, ammonia-N, and volatile fatty acids (VFAs), were determined in vitro using continuous culture. The results showed that final bodyweight was lower (p < 0.05), while feed intake and the feed-to-gain ratio were increased (p < 0.05) in sprouted barley treatments. Nutrient analysis indicators of sprouted barley treatments (25 to100%) were lower (p < 0.05) for DM, crude protein, acid detergent fiber, lignin and ash, and higher for total digestible nutrients, NDF, fat, phosphorus, zinc, copper, and net energy than the traditional diet. In the in vivo study, the digestibility of nutrients in sprouted barley treatments was improved (p < 0.05), while the diet (sprouted barley 100%) had the lowest digestibility of DM, OM, and NDF compared with the other treatments in the in vitro study. In conclusion, the addition of sprouted barley improved digestibility, and fermentation characteristics, while having a negative effect on growth. Further studies are recommended for optimal growth performance.