Valutazione della struttura della fibra in razioni unifeed mediante metodiche di campo

Fiber plays a fundamental role in ruminant and dairy cattle nutrition. Fiber requirement has been well characterized for dairy cow and ration are always adjusted for this parameter from a quantitative and qualitative point of view. After the introduction of total mixed ration in farm practice, there has been a growing demand for the possibility of measuring fiber physical characteristics with the aim to maximize productivity and reduce health problems. The main parameter to measure fiber physical form is Physical Effective NDF (peNDF), which includes physical and chemical informations. The Penn State Particle Separator (PSPS) is an instrument used to perform this measurement but, based on some research, it is not fully accurate in determining peNDF in rations. Because of this, field measurement of peNDF is still a challenge for practitioners. In this work, 3 different instruments developed by Cortal Extrasoy s.p.a. (“Ruminometro”, “Densitometro” and “Fibrometro”) are tested as predictors of productive parameters and are compared to PSPS as tools to measure peNDF. Some similarities were found between Fibrometro and PSPS such as between Ruminometro and Densitometro. Fibrometro and PSPS data resulted also related with milk yield. More research are needed to validate the use of these tools for fiber physical form measurement and to establish a relationship between these data and productivity and animal health.