پردیس کشاورزی و منابع طبیعی دانشگاه تهران Iranian Journal of animal Science 2008-4773 47 2 2016 08 22 Effects of alfalfa maturity and cutting times on availability of alfalfa hay protein for dairy cows Effects of alfalfa maturity and cutting times on availability of alfalfa hay protein for dairy cows 185 191 59023 10.22059/ijas.2016.59023 FA Safora Yousefinezhad Former M.Sc. Student, Department of Animal Science, University of Ilam, Ilam, Iran Farshid Fattahnia Associate Professor, Department of Animal Science, University of Ilam, Ilam, Iran Mehdi Rashnavadi Assistant Professor, Department of Animal Science, University of Ilam, Ilam, Iran Sayed Gholamreza Mossavi Former M.Sc. Student, Department of Animal Science, University of Ilam, Ilam, Iran Golnaz Taasoli Assistant Professor, Department of Animal Science, University of Ilam, Ilam, Iran Journal Article 2016 01 11 This experiment was conducted to consider the effects of maturity and cutting time on chemical composition and available protein content of alfalfa hay for dairy cows.. Alfalfa hay harvested at two maturity stages (Pre-bloom and Early bloom) and two cutting times (Morning and Afternoon). Available protein was predicted using NRC (2001) and DVE/OEB (1994) models. In the NRC model (2001), alfalfa hay harvested pre-bloom and in the afternoon had higher microbial protein synthesized in the rumen from energy and absorbable microbial protein and lower ruminal degraded protein balance (P<0.05). But, metabolizable protein content was not affected by maturity stage and cutting time (P>0.05). In the DVE/OEB model, pre-bloom alfalfa harvested in the afternoon had higher fermentable organic matter, microbial protein synthesized from organic matter and absorbable microbial protein and lower ruminal degraded protein balance (P<0.05). In conclusion, pre-bloom alfalfa hay harvested in the afternoon had higher available protein for dairy cows. This experiment was conducted to consider the effects of maturity and cutting time on chemical composition and available protein content of alfalfa hay for dairy cows.. Alfalfa hay harvested at two maturity stages (Pre-bloom and Early bloom) and two cutting times (Morning and Afternoon). Available protein was predicted using NRC (2001) and DVE/OEB (1994) models. In the NRC model (2001), alfalfa hay harvested pre-bloom and in the afternoon had higher microbial protein synthesized in the rumen from energy and absorbable microbial protein and lower ruminal degraded protein balance (P<0.05). But, metabolizable protein content was not affected by maturity stage and cutting time (P>0.05). In the DVE/OEB model, pre-bloom alfalfa harvested in the afternoon had higher fermentable organic matter, microbial protein synthesized from organic matter and absorbable microbial protein and lower ruminal degraded protein balance (P<0.05). In conclusion, pre-bloom alfalfa hay harvested in the afternoon had higher available protein for dairy cows. https://ijas.ut.ac.ir/article_59023_d526fca278570655cb49de4b8fc6cf5f.pdf