Annual and seasonal changes in mineral contents (Ca, Mg, P, K and Na) of grazed clover-grass mixtures in organic farming

Abstract

A grazed field experiment was established in 1995 to evaluate alsike clover (Trifoliun hybridum L.), red clover (Trifolium pratense L.) and white clover (Trifolium repens L.) in clover-grass mixtures under organic farming practices. In this study the effect of seed mixture (alsike clover, red clover, white clover, white and alsike clover or grass mixture), year (1997, 1998) and grazing period (5 per grazing season) on the herbage calcium (Ca), magnesium (Mg), potassium (K) phosphorous (P) and sodium (Na) contents was assessed and the relationships between botanical proportions and herbage mineral contents were studied. Herbage Ca and Na contents varied between the seed mixtures, Ca, Mg, P and Na contents between the years and all measured minerals, except Na, between the grazing periods. The white clover mixture resulted in higher Ca and Na contents. The contents of Ca and Mg were positively related with the proportions of clovers and weeds and were higher in 1997. The contents of P and K were higher in the rainy summer of 1998. The seed mixtures resulted in similar mean K/(Ca + Mg) equivalent ratios, but the Ca/P ratio was higher for the white clover mixture. Mineral rations varied between and within grazing seasons. Under organic practices the supply of minerals in the pasture herbage varied temporally and according to the botanical contents and was unable to meet fully the requirements of dairy cows. Additional mineral feeding is recommended for organic farming systems to balance the dietary mineral contents for grazing cows.

Performance off Forage Crops and Grass Mixtures in Kosovo

“…The protein content (PC) is a quantitative trait and several studies have pointed out that there are a great number of genes involved in its control [21]. However, it is a challenge to manage the mineral supply of ruminants fed on grassland, because mineral concentrations in the herbage are influenced by a number of factors including species composition of the sward [22].…”

Legumes in Finnish agriculture: history, present status and future prospects

“…Red clover also has high yields of digestible organic matter, metabolizable energy and N , Halling et al 2002, Abberton and Marshall 2005. Clovers are richer in calcium, magnesium and many trace elements than grasses (Leaver 1985, Nykänen-Kurki and Hakkola 1994, Kuusela 2006) and legumes take up phosphorus, sulphur and potassium in relatively large amounts (Mulder et al 1977, Marschner 1995. The decrease of organic matter digestibility in late summer is slower for clovers than for grasses, which gives a larger window of time for optimal harvesting of mixtures, as well (Rinne and Nykänen 2000).…”

“…1980(Fig. 1990 , Suomen tilastollinen vuosikirja 1953Suomen tilastollinen vuosikirja (1951Suomen tilastollinen vuosikirja -1952, Maataloustilastollinen kuukausikatsaus 1953-1964, Maatalouden vuositilasto 1965-1982, Maatilatilastollinen vuosikirja 1983-2006, and TIKE Tiedote (2007). 192019301940195019601970 3).…”

Impact of Agricultural Practices on the Botanical Composition Changes and Nutritional Value of Natural Grassland, Type Agroseietum Vulgaris

“…Among the various constituents of herbage quality that are important for ruminants is the need for sufficient amounts of minerals in the diet to ensure good health and performance (Underwood and Suttlen, 1999). However, it is a challenge to manage the mineral supply of ruminants fed on grassland, because mineral concentrations in the herbage are influenced by a number of factors including species composition of the sward (Kuusela, 2006), time of the year (Høgh-Jensen et al, 2006) and fertilization (Soder and Stout, 2003).…”