Changes in chemical composition and digestibility of forage from perennial ryegrass, alfalfa and their mixtures
Yordanka Naydenova, Aneliya Katova
Резюме: Ecologically and effectively forage production for ruminant nutrition requires selection of species
and varieties of perennial grass and legume crops in creating of sown grasslands. The field trial
was carried out at the Institute of Forage Crops – Pleven (2012–2014) with the aim to study changes
in chemical composition and digestibility of the forage from the first perennial ryegrass Bulgarian
variety IFK Harmoniya and tetraploid breeding population NBG in pure stand and in mixture with
the most spread alfalfa varieties Pleven 6 and Dara. The principal composition, cell wall fiber components content, and in vitro dry matter digestibility of the dry biomass from perennial multi-cutting forage species were estimated. It was found that: crude protein content during first year and first growth for the two species and varieties is between close margins (18.02% – 20.47%), and mixture NBG and Pleven 6, followed by Harmoniya and Dara had the highest values. The tetraploid NBG in pure stand in third growth had maximum crude protein content 17.96%, together with mixture Harmoniya – Pleven 6. There were evident differences between variety Harmoniya and tetraploid NBG – 13.51% and 19.20%, respectively for CP, close to this of alfalfa 19.46-21.42% during next years in first growth. Crude protein content for two perennial ryegrasses didn’t distinguishe in second growth and was higher for alfalfa 19.00-21.30%. Tetraploid NBG had the lowest degree of lignification in first and second growths, coeff. 4.0 and values increased in third growth. Concerning alfalfa the degree of lignification was three times higher with comparison with perennial ryegrass in the vegetation period, coeff. 17.1-23.2. Grass component had very high digestibility 79–83% in comparison with alfalfa 66–69% in the first establishing year. For the mixtures, the digestibility of two perennial ryegrass varieties was lower compare to pure stand but higher than this of alfalfa. The digestibility of alfalfa variety Dara was higher than those of variety Pleven 6 (68.52 against 65.46%). The digestibility of perennial ryegrass in first and second growths was higher compare to alfalfa and NBG tetraploid was more digestible than Harmoniya. The digestibility of second growth was the lowest for all variants but the most digestible was NBG 62.49%. In the third growth the digestibility of alfalfa was higher than that of perennial ryegrass. The highest digestibility in fourth growth was established for mixture perennial ryegrass NBG – alfalfa Pleven 6.
and varieties of perennial grass and legume crops in creating of sown grasslands. The field trial
was carried out at the Institute of Forage Crops – Pleven (2012–2014) with the aim to study changes
in chemical composition and digestibility of the forage from the first perennial ryegrass Bulgarian
variety IFK Harmoniya and tetraploid breeding population NBG in pure stand and in mixture with
the most spread alfalfa varieties Pleven 6 and Dara. The principal composition, cell wall fiber components content, and in vitro dry matter digestibility of the dry biomass from perennial multi-cutting forage species were estimated. It was found that: crude protein content during first year and first growth for the two species and varieties is between close margins (18.02% – 20.47%), and mixture NBG and Pleven 6, followed by Harmoniya and Dara had the highest values. The tetraploid NBG in pure stand in third growth had maximum crude protein content 17.96%, together with mixture Harmoniya – Pleven 6. There were evident differences between variety Harmoniya and tetraploid NBG – 13.51% and 19.20%, respectively for CP, close to this of alfalfa 19.46-21.42% during next years in first growth. Crude protein content for two perennial ryegrasses didn’t distinguishe in second growth and was higher for alfalfa 19.00-21.30%. Tetraploid NBG had the lowest degree of lignification in first and second growths, coeff. 4.0 and values increased in third growth. Concerning alfalfa the degree of lignification was three times higher with comparison with perennial ryegrass in the vegetation period, coeff. 17.1-23.2. Grass component had very high digestibility 79–83% in comparison with alfalfa 66–69% in the first establishing year. For the mixtures, the digestibility of two perennial ryegrass varieties was lower compare to pure stand but higher than this of alfalfa. The digestibility of alfalfa variety Dara was higher than those of variety Pleven 6 (68.52 against 65.46%). The digestibility of perennial ryegrass in first and second growths was higher compare to alfalfa and NBG tetraploid was more digestible than Harmoniya. The digestibility of second growth was the lowest for all variants but the most digestible was NBG 62.49%. In the third growth the digestibility of alfalfa was higher than that of perennial ryegrass. The highest digestibility in fourth growth was established for mixture perennial ryegrass NBG – alfalfa Pleven 6.
Ключови думи: alfalfa; cell wall fiber; chemical composition; digestibility; grass-legume mixtures; perennial ryegrass
Дата на публикуване: 2017-02-09
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