The effect of high dietary Cu on health, growth performance, and Cu status in young goats

• Published in: Small ruminant research Vol. 66; no. 1; pp. 85 - 91
• Main Authors: Solaiman, S.G., Shoemaker, C.E., D’Andrea, G.H.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-11-2006
• Subjects: adverse effects; animal feeding; animal nutrition; animal organs; animal tissues; Boer; copper; Cu status; diet; dietary mineral supplements; dietary minerals; feed conversion; feed intake; Goat; health status; High dietary Cu; kids; livestock production; liveweight gain; megadose; nutrient requirements; physiological response; Spanish (goat breed); toxicity; Goat; High dietary Cu; Performance; Cu status
• ISSN: 0921-4488; 1879-0941
• DOI: 10.1016/j.smallrumres.2005.07.024

An experiment was conducted to determine the effect of high dietary Cu on growth performance and Cu status in goat kids. Fifteen Boer
×
Spanish goat kids (4–5 months of age; average BW
=
21.3
±
0.7
kg) were housed in individual pens and randomly assigned to three different treatments. Treatments consisted of (1) control (no additional Cu), (2) 100
mg Cu/d and (3) 200
mg Cu/d from an inorganic source Cu sulfate. Copper was placed in gelatin capsules and inserted in the esophagus via balling gun before AM feeding. Animals were fed ad libitum twice a day a 70:30 grain:hay diet to meet daily requirements of growing kids according to NRC [NRC, 1981. Nutrient requirements of domestic animals. Nutrient requirements of goats: angora, dairy and meat goats in temperate and tropical countries, No. 15, National Research Council, National Academy of Science, Washington, DC]. Feed intake and refusals were monitored daily and intake was adjusted weekly for 14 weeks. Body weight was recorded after 4
h withdrawals from feed and water, for 2 consecutive days every 2 weeks. Vital signs and blood samples were obtained every 2 weeks. After 14 weeks, sorbitol dehydrogenase (SDH) levels were determined and animals were slaughtered. Liver, bile, longissimus muscle (LM) and kidney samples were obtained postmortem. Copper supplementation had no effect (
P
>
0.05) on respiration rate, heart rate, rectal temperature, or serum SDH activity. Average daily gain over 10 weeks was improved with 100
mg Cu intake (quadratic,
P
=
0.01). Average daily feed intake decreased linearly (linear,
P
=
0.05) as Cu increased in the diet with the control group consuming a higher grain:hay ratio in the diet (linear,
P
=
0.03). Gain efficiency was higher (quadratic,
P
=
0.02) with 100
mg Cu group when compared to control and 200
mg Cu groups. Liver and fecal Cu concentrations increased (linear,
P
=
0.0001) as Cu increased in the diet; however, serum, bile, and kidney Cu concentrations did not differ. These data indicate that high level of Cu fed to Boer
×
Spanish goat kids at 100
mg/d can enhance average daily gain and gain efficiency without eliciting Cu toxicity.