Evaluating the effects of finishing diet and feeding location on sheep performance, carcass characteristics, and internal parasites
Abstract
A 3 yr experiment was conducted to evaluate the influence of diet and feeding location on animal performance, carcass characteristics, whole blood counts, and internal parasite burden of lambs assigned to 1 of 4 treatments: 1) confinement fed 71% alfalfa, 18% barley pellet, 5% molasses, 0.013% Bovatec, 6.1% vitamin/mineral package diet (<strong>CALF)</strong>, 2) confinement fed 60% barley, 26% alfalfa pellet, 4% molasses, 2.5% soybean-hi pro, 0.016% Bovatec, 7.4% vitamin/mineral package diet (<strong>CBAR</strong>), 3) field fed 71% alfalfa, 18% barley pellet, 5% molasses, 0.013% Bovatec, 6.1% vitamin/mineral package diet (<strong>FALF</strong>), and 4) field fed 60% barley, 26% alfalfa pellet, 4% molasses, 2.5% soybean-hi pro, 0.016% Bovatec, 7.4% vitamin/mineral package diet (<strong>FBAR</strong>). Lambs had <italic>ad libitum</italic> access to feed and water during the 60-65 d experimental period each year. A year × location interaction was detected for ending BW, ADG, and DMI; therefore results are presented by year. In all years, cost of gain and DMI were greater for CALF and FALF than for CBAR and FBAR feed treatments (<italic>p</italic>≤ 0.03). In yr 2 and 3 field treatments had greater ending BW and ADG than confinement treatments. For all years, diet did not affect ending BW or ADG. In yr 1 dressing percent and rib eye area were greater for field finished lambs than confinement finished (<italic>p</italic>≤ 0.02) and Warner-Bratzler shear force was greater for CALF and FALF (<italic>p</italic> =0.03). In yr 2 lambs in FALF and FBAR treatments had greater leg scores and conformation than CALF and CBAR (<italic>p</italic> =0.09). In yr 1, FALF had a greater small intestine total worm count than all other treatments. In yr 1, ending <italic>Trichostrongyle </italic>type egg counts were greater for FALF (<italic>p</italic>=0.05). In yr 2, ending <italic>Nematodirus spp</italic>. egg counts were greater for FALF and lowest for CBAR (<italic>p</italic>< 0.01). Abomasum <italic>Teladorsagia circumcinta</italic> worm burden was greater in CALF than all other treatments (<italic>p</italic>= 0.07) in yr 2. While field finishing lambs with a grain- or forage-based diet we conclude that it is possible to produce a quality lamb product without adverse effects to animal performance, carcass quality or increasing parasite burdens.