Composición y calidad nutritiva de una pastura con base en festuca pastoreada por vacas lecheras, con distintas alturas remanentes en primavera

The effect of the remaining height (AR) of a fescue on the nutritional and botanical composition of the pasture was studied. The objective was to test higher heights than those currently recommended and observe their impact on the aforementioned variables. The criterion for entering grazing was when the fescue reached the physiological state of three leaves. During spring, two remaining heights were compared: control treatment (TC; 9 cm) and lax treatment (TL; 15 cm). Twenty-four multiparous Holstein cows calved in autumn, with 3.2 ± 0.82 lactations, 580 ± 41.3 kg LW and 2.5 ± 0.16 units of BCW at calving were blocked by the number of lactations, LW, calving date and CC. It was managed with rotational grazing, where each grazing lasted an average of 7.5 and 5 days, for TC and TL; respectively. During the experiment in the spring, TC animals tended to increase their grazing time, with longer duration sessions compared to TL. The TL animals showed more stable behavior throughout the grazing days, and managed to harvest higher quality forage. The results show that there is a response in nutritional quality to RA that is laxer than those recommended at the national level. Higher AR allowed the animals to graze better quality forage, in less time and with greater use of nutrients.