| dc.description.abstract | Livestock grazing on outfield pastures to utilize inexpensive forage and save infield pastures to harvest winter feed is an important focus topic in Norwegian agriculture. It is important for the health and biodiversity of native grassland communities to be maintained to prevent secondary succession. One method of grassland management is grazing cattle on outfield pastures. This develops a symbiotic relationship where native grassland is maintained while cattle are nourished without sacrificing their growth and development.
In Ringsaker and Vang almenning areas of Hedmark County, three dairy farms practice summer grazing on outfield pastures and allowed 41 of their Norwegian Red heifers to participate in this study. One farm allowed their heifers to forage freely (O-group) and the other farms had heifers in a restricted area (P-group). The aim of this study was to identify if an outfield grazing production system could support those heifers growth, body weight, and body condition as recommended by the Norwegian dairy coop Tine. Subsequently, I measured both live body weight and body condition of those 41 heifers.
The results indicated that the only heifers that gained body weight during the grazing season were those heifers that originated from the open grazing production system (O-group). The heifers in the O-group gained on average 17.4 kg while grazing on outfield pastures. Those heifers in the O-group were also the closest to the suggested weight recommended by Tine, with an average of 28.3 kg below the recommended weight for heifers’ respected ages. The heifers in the Pen grazing production system (P-group) lost an extensive amount of weight. Heifers in the P-group lost on average 60.9 kg, and were also 95 kg below their recommended Tine weight. In addition, this study also found a negative correlation between overweight heifers at the start of the grazing season and percentage body weight loss. Those heifers in our study that were the most overweight lost large percentage of their body weight over the grazing season.
In this study the results illustrate that grazing heifers on outfield pastures may be accomplished without sacrificing livestock production through the use of an open grazing management production system. | nb_NO |
