The aim of this study was to determine the green herbage and dry herbage yield, chemical and nutritional values and RFV of alfalfa (Medicago sativa L.) at different stages of maturity under Isparta ecological conditions in 2012. To achieve this goal random sampling plots was created according to an experimentation pattern, and the number of harvests was determined according to regional conditions. In chemical analysis, the following samples were analyzed for Dry Matter (DM), Crude Protein (CP), Ether Extract (EE), Ash, Crude Fiber (CF), Nitrogen Free Extract (NFE), Notral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF), as well as macro and micro minerals. The highest total green herbage yield was 9609.33 kg/da during the budding period, which decreased by 28% with maturity. The highest total dry matter yield, which depends on hay yield, was determined as 1742.63 kg/da at the beginning of the flowering period. The highest CP was determined during the budding period and decreased with maturity. DM, CS, NDF and ADF content increased while ash, Digestible Dry Matter (DDM), Total Digestible Nutrients (TDN), Dry Matter Intake (DMI), Metabolisable Energy (ME), Net Energy Lactation (NEL), and Digestible Energy (DE) content decreased with maturity. The highest RFV was determined during budding and the beginning of the flowering periods. Taking both yield and feed value results into consideration based on Isparta's conditions, the best harvesting period of alfalfa was determined to be at the beginning of the flowering period.

Unreliable measures of undigested neutral detergent fiber (uNDF) can influence animal nutrition and performance when balancing diets based on flawed forage quality estimates. Two common techniques for in vitro long digestions are the conventional flask method and the ANKOM filtration bag procedure. An ANKOM filter bag has been developed (F58) with an 8‐ to 10‐μm pore size, decreasing the chance of losing particles during neutral detergent fiber (NDF) procedure, but it has not been evaluated for use with in vitro digestions. Our objective was to compare ANKOM F58 bags with F57 bags and the conventional flask method for in vitro long digestions. Analyses incorporated 24 forage samples representing a broad range of temperate and tropical grasses and legumes. A commercial laboratory analyzed the same samples using the conventional flask procedure. Separate analyses evaluated the effect of Na2SO3 for ANKOM F57 and F58 methods and the effect of ruminal fluid plus buffer refreshing at 2‐d intervals with ANKOM F57. Undigested NDF at 240 h on an organic matter basis (uNDF240om) values between methods were different from one another, but rate calculations derived from uNDF240om values were not different. Method pore size was highly correlated (r = −0.993) with uNDF240om values. Results showed that refreshing ruminal inoculum plus buffer at 2‐d intervals for ANKOM F57 and the addition of Na2SO3 during the analysis of ash‐free NDF on an organic matter basis (aNDFom) after ANKOM F57 and F58 in vitro digestions both had significant effects on lowering uNDF240om values.

Botanical composition of alfalfa (Medicago sativa L.)–grass fresh and ensiled mixtures is a key parameter for assessing forage and diet quality as well as for managing mixed stands. Previous attempts to validate near‐infrared reflectance spectroscopy (NIRS) equations for estimating botanical composition have had mixed results. This study was conducted to develop a robust NIRS method to estimate botanical composition of binary alfalfa–grass mixtures. Alfalfa–grass samples were collected across New York State over four growing seasons, hand separated, and a subset were ensiled separately. Dry samples were coarsely ground, mixed in known proportions, and reground for analysis by NIRS at Dairy One Forage Laboratory, Ithaca, NY. Samples were mixed to range from 0 to 100% alfalfa for NIRS calibration, with a total of 741 individual samples from 3 yr used for calibration of three NIRS instruments and samples from a fourth year used for validation. Grass composition was predicted with good precision and accuracy showing biases of 2.49 and standard errors of prediction (SEP) of 5.06, with R2 of 0.972, using the equation developed across multiple instruments. With selection of a robust set of calibration samples over many environments, NIRS can be used to determine the botanical composition of fresh‐dried or ensiled‐dried alfalfa–grass samples, and replicate scans from multiple instruments can be combined to develop a single calibration that will perform with equal efficiency across different instruments.

The aim of this study was to determine the degradation in the rumen for the dry matter (DM), organic matter (OM) and crude protein (CP) of alfalfa (Medicago sativa L.) harvested at different maturity stages by using an in situ nylon bag method. Maturity and harvesting effects were observed in ruminally degradable DM, OM and CP. High correlations between in situ degradability and maturity were determined. Alfalfa harvested in the bud period exhibited more extensive ruminal DM, OM and CP degradation than that harvested at other maturity stages. The alfalfa hay’s DM, OM and CP degradability were lowest (62.18%, 59.52% and 76.31%, respectively) in its most mature period of seed setting; its degradability decreased with maturity (17%, 14% and 13%, respectively).