Lamb production on wheatgrasses and wheatgrass/sainfoin mixtures

Date

1990-08

Journal Title

Journal ISSN

Volume Title

Publisher

Texas Tech University

Abstract

Previous research indicates that some wheatgrasses and sainfoin produce high quality forage from early spring to early summer on the Southern Great Plains, Little information is available on their potential for lamb production under grazing. The objectives were to: 1)determine the levels and economics of spring lamb production from 3 irrigated wheatgrasses, 'Hycrest' [Agropyron crlstatum (L,) X A. desertorum] f 'Luna' {Thinopyrum intermedium), and 'Jose' (r. ponticum) grown alone and with 'Renumex' sainfoin {Onobrychis viciifolia) , 2) determine which variables could be used to model cumulative weight gains (CUM)using time series regression analysis, and 3) validate the models. Replicated pastures of wheatgrasses and sainfoin were grown in alternate paired rows on a fine, mixed thermic Torrertic Paleustoll. Within a replication, 5 paddocks were rotationally grazed by weaned Rambouillet X Suffolk wether lambs for an average of 77 d in the springs of 1987 and 1988, A fixed grazing pressure of 6,5% of body weight d~i allotment of dry matter was maintained by the 'put-and-take' method. Herbage quality, quantity, and plant parts were estimated from pregrazing, after 2 and 4 d of grazing, and postgrazing (7 d) harvests. Seasonal average daily gains (ADG) were 56, 69, 45, 95, 104, and 80 g d~^ for Hycrest, Luna, Jose, Hycrest/sainfoin, Luna/sainfoin and Jose/ sainfoin, respectively- Lamb production ha~^ (PROD ha~i) for mixtures was similar (463 kg ha~i) , but higher than monocultures (238 kg ha~l) , Mixtures in comparison to monocultures had greater CUM (70%), PROD ha~l (94%), feed conversion (55%), and intakes (23%), Body condition scores were highest (moderately fat) for lambs with the highest (104 g d"l) weight gains. Seasonal mean crude protein (CP) was lowest for Jose (12.8%) and highest for Hycrest/sainfoin (17%).

Description

Keywords

Sainfoin, Wheatgrasses, Sheep

Citation