Performance of steers supplemented with copper before and during receiving at the feedlot

Abstract

. 2002. Performance of steers supplemented with copper before and during receiving at the feedlot. Can. J. Anim. Sci. 82: 87-93. The effects of supplemental Cu in the diets of beef steers grazing winter-annual pasture and(or) during receiving at a feedlot were examined. On 19 February, 84 steers (average BW = 216 ± 1.5 kg) were weighed and randomly assigned to 12 bermudagrass pastures (0.81 ha each) overseeded with wheat, rye, and annual ryegrass (seven steers/pasture). All steers were fed 0.91 kg daily of a corn-based supplement containing a basal level of Cu (control; 21 mg of Cu d -1 ) while grazing winter-annual pasture until 16 April. On 16 April, the steers were weighed, bled via jugular venipuncture, and one-half of the steers were supplemented with an additional 1.5 g of Cu proteinate (CuPRO; 150 mg Cu d -1 ), during the last 29 d of grazing before shipping to a feedlot. On 17 May, the steers were shipped to a research feedlot (14 h transit, 1.016 km). After arrival on 18 May, one-half of the groups of cattle that received each treatment during grazing received 150 mg of Cu from CuPRO daily (2 × 2 factorial) for 42 d. The supplementation of steers grazing pasture with additional Cu from CuPRO during the last 29 d of grazing tended to increase (P = 0.10) ADG and BW on day 29. The BW advantage expressed by CuPRO supplemented steers was not as apparent (P = 0.18) upon arrival at the feedlot, but at the conclusion of the receiving period, steers fed CuPRO on pasture were 6.3 kg heavier (P = 0.04). No benefit was noted (P > 0.14) when CuPRO was fed during receiving at the feedlot. During the grazing phase, additional Cu from CuPRO seemed beneficial compared to basal Cu levels. ont été pesés puis répartis au hasard dans 12 prés (de 0,81 ha chacun) de chiendent pied-de-poule sursemés de blé, de seigle et de ray-grass annuel (7 animaux par pâturage). Chaque jour, les bouvillons ont reçu 0,91 kg d'un supplément à base de maïs contenant une quantité minimale de cuivre (témoin; 21 mg de Cu par jour) pendant la période de paissance, jusqu'au 16 avril. À cette date, les auteurs ont de nouveau pesé les bêtes, ont prélevé des échantillons de sang par ponction de la jugulaire puis ont administré à la moitié un second supplément de 1,5 g de protéinate de cuivre (CuPRO; 150 mg de Cu par jour) pendant les 29 derniers jours de paissance précédant l'expédition au parc d'engraissement. Le 17 mai, les animaux ont été envoyés à un parc d'élevage expérimental (14 h de transport, 1 016 km). À leur arrivée, le lendemain, la moitié des bouvillons de chaque groupe a reçu 150 mg de CuPRO (répartition factorielle 2 × 2) et quotidiennement par la suite, pendant 42 jours. L'administration du supplément aux bouvillons pendant les 29 derniers jours de paissance a tendance à augmenter (P = 0,10) le GQM et le poids corporel au 29 e jour. L'avantage procuré par le CuPRO n'était pas manifeste (P = 0,18) à l'arrivée au parc d'engraissement, mais à la fin de la période d'élevage, les animaux de ce groupe pesaient 6,3 kg de plus (P = 0,04). L'ad...

Trace Minerals Supplementation with Great Impact on Beef Cattle Immunity and Health

“…During the last decades, numerous studies have demonstrated the benefits of oral TM supplementation on beef cattle immunity, health and performance [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. However, other studies have shown marginal or insignificant effects of oral TM supplementation on beef cattle metabolism, growth, immunity and health [ 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 , 103 , 104 , 105 , 106 , 107 , 108 ]. Many of these studies have provided inconsistent results due to differences in mineral forms supplemented (organic versus inorganic), high variability in TM concentration in control diets, the animals’ TM requirements and initial TM status, variation in animal intake and absorption, chemical mineral interactions and antagonisms, level of stress, and differences in experimental models and endpoints.…”

“…Other studies failed to demonstrate positive effects of Cu supplementation on beef cattle health, or had inconsistent results [ 47 , 96 , 97 , 100 , 104 , 115 ]. Stressed calves supplemented with Cu (5 mg/kg DM for 133 d) had increased antibody production (to pig red blood cells) and cell-mediated immune response (to dinitrochlorobenzene stimulation) [ 120 ].…”

BILL E. KUNKLE INTERDISCIPLINARY BEEF SYMPOSIUM: Impact of mineral and vitamin status on beef cattle immune function and health1,2

“…Studies investigating the effect of supplemental Cu in the receiving ration have generally found no benefits on health (Galyean et al, 1995;Beck et al, 2002). However, sheep that are Cu deficient have decreased resistance to bacterial infection (Woolliams et al, 1986).…”