Effects of Soil Moisture Deficit on Forage Quality, Digestibility, and Protein Fractionation of Kura Clover

Abstract

Kura clover (Trifolium ambiguum M.B.) is a persistent rhizomatous forage legume with great potential for permanent pastures. The effects of a soil moisture deficit on forage quality, digestibility and protein fractionation of two cultivars of Kura clover (Endura and Rhizo) were investigated in this study for 1 year. The responses of alfalfa (Medicago sativa L.) and red clover (Trifolium pratense L.) were also characterized. Stands of each species were field-grown and submitted to two soil water regimes promoting soil moisture deficits and well-watered (i.e. control) conditions. There were no interactions between species and soil water regimes. Soil moisture deficit increased acid detergent fibre (ADF) but reduced acid detergent lignin (ADL) content and consequently increased forage digestibility. It had only minor effects on protein content and fractionation. Species varied for most parameters measured. Kura clover generally had the lowest neutral detergent fibre (NDF), ADF and ADL contents, and consequently the greatest digestibility (83.9 %). Species also differed in their crude protein fractionation. Kura clover and red clover had a lower proportion of non-protein nitrogen (NPN; A fraction) and a greater proportion of true protein (B fraction) (30.9 and 64.5 %, respectively) than alfalfa (36.4 and 57.4 %, respectively). Kura clover also had the lowest proportion (i.e. 4.7 %) of acid detergent insoluble protein (ADIP; C fraction) of all species tested. Endura Kura clover often had a higher forage quality than Rhizo. This study confirms that Kura clover produces high-quality forage and provides the first estimates of protein fractionation in this species.

Chemical composition and ruminal nutrient degradabilities of fresh and ensiled Kura clover (Trifolium ambiguum M.B.)

“…However, cultivars tested in that study (Endura and Rhizo) were different from those evaluated in the present study. The chemical composition for the two Kura clover cultivars in the present study are in good agreement with the literature values previously reported for various Kura clover cultivars (Allinson et al 1985;Sheaffer and Marten 1991;Sleugh et al 2000;Seguin et al 2002).…”

“…Results are in accordance with those of Seguin et al (2002) who found no differences in protein fractions between Endura and Rhizo Kura clover cultivars. Protein fractions of Kura clover were however, significantly affected by ensiling (Table 3).…”

“…Both cultivars had similar NDF (average of 355 g kg -1 of DM), ADF (281 g kg -1 of DM), EE (24 g kg -1 of DM), total carbohydrates (672 g kg -1 of DM), non-structural carbohydrates (354 g kg -1 of DM), TDN (650 g kg -1 of DM), and NE l (6.17 MJ kg -1 DM) contents. In a previous study, Seguin et al (2002) reported differences in NDF and ADF levels between Kura clover cultivars. However, cultivars tested in that study (Endura and Rhizo) were different from those evaluated in the present study.…”

Changes in nutritive value of alfalfa (Medicago × varia T. Martyn) and Festulolium (Festulolium braunii (K. Richt) A. Camus) under drought stress

“…() and Seguin et al. () found a minor effect of drought stress on protein content. Our studies showed a small (statistically unproven) increase in CP content under drought, both in alfalfa and Festulolium .…”

Influence of non-cellulose structural carbohydrate composition on plant material decomposition in soil

“…In decomposition studies, proximate analyses are commonly used to determine plant material composition (Quemada and Cabrera 1995;Henriksen and Breland 1999;Gunnarsson and Marstorp 2002;Seguin et al 2002;Henriksen et al 2007). A widely used proximate analysis is the neutral detergent solution (NDF)/acid detergent solution (ADF) method (Goering and van Soest 1970) with which plant materials are extracted under reflux successively with a NDF and an ADF.…”