Energy source and ionophore supplementation effects on lamb growth, carcass characteristics, visceral organ mass, diet digestibility, and nitrogen metabolism

Citation
Fl. Fluharty et al., Energy source and ionophore supplementation effects on lamb growth, carcass characteristics, visceral organ mass, diet digestibility, and nitrogen metabolism, J ANIM SCI, 77(4), 1999, pp. 816-823
Citations number
23
Categorie Soggetti
Animal Sciences
Journal title
JOURNAL OF ANIMAL SCIENCE
ISSN journal
00218812 → ACNP
Volume
77
Issue
4
Year of publication
1999
Pages
816 - 823
Database
ISI
SICI code
0021-8812(199904)77:4<816:ESAISE>2.0.ZU;2-#
Abstract
In Exp. 1, 72 Targhee lambs (initial BW 22.1 +/- .3 kg) were used to determ ine the effects of energy source (alfalfa pasture vs limit-fed, all-concent rate) and ionophore addition on performance, visceral organ mass, and carca ss characteristics. There were no differences (P > .10) in ADG or gain/feed due to ionophore supplementation. Lambs that grazed alfalfa had greater (P < .05) liver, omasum, abomasum, small intestine, cecum, and large intestin e weights than did lambs fed the concentrate diet. Lambs fed the concentrat e diet had greater (P < .01) hot carcass weights, larger (P < .01) loin eye areas, and greater (P < .001) dressing percentages than lambs that grazed alfalfa. In Exp. 2, lambs offered the concentrate diet had greater (P < .00 1) DM and OM digestibilities than lambs offered alfalfa (89.5 and 91.1 vs 7 2.4 and 74.2%, respectively). Apparent and true N digestibilities were grea ter (P < .001) for the concentrate diet than for alfalfa (90.9 and 101.7 vs 77.7 and 91.9%, respectively). Likewise, grams of N retained per day were twice as great (P < .001) with the concentrate diet than with alfalfa (14.9 vs 6.0 g/ d). The greater visceral organ mass and resulting increases in e nergy and protein requirements in lambs that grazed alfalfa were probably r esponsible for the lesser hot carcass weight and dressing percentage compar ed with lambs fed 100% concentrate.