The effect of different levels of L-carnitine on performance, blood parameters and carcass characteristics of broiler chickens fed with high fat diets under heat stress condition


1 Department of Animal Sciences, Faculty of Agriculture, University of Razi, Kermanshah-Iran

2 Department of Animal Sciences, Faculty of Agriculture, University of Urmia, Urmia -Iran


BACKGROUND: Heat stress declines the performance through physiologic changes of the poultry. OBJECTIVES: This experiment was conducted to evaluate the effects of different levels of L-carnitine on performance, carcass characteristics and some blood parameters of broiler chickens fed with high fat diets under heat stress. METHODS: Two hundred one-day-old broiler chicks (Ross 308) were used in a completely randomized design by four treatments and five replicates (pen) 10 birds in each replicate. The chickens of experimental treatments were fed with basal diet (control group) and the diets plus the different levels of 100, 200 and 300 mg/kg L-carnitine. The experimental diets were used during the finisher period (day 24 to 42 of age) and under heat stress (32±1ºC as cyclic from 9.00 AM to 5.00 PM). RESULTS: The results showed that the chicks fed with the highest L-carnitine had the higher weight gain during the finisher period as compared to control and the lower L-carnitine fed chicks (p<0.05). Furthermore, the feed conversion ratio of birds fed with the medium and high L-carnitine levels (100 and 300 mg) was lower than that of control birds (p<0.05). In orthogonal contrasts, L-carnitine supplementation caused the improvement in weight gain and feed conversion ratio during both the finisher and whole experimental periods (p<0.05). The consumption of highest L-carnitine decreased the abdominal fat as compared to control (p<0.05). In orthogonal contrasts, L-carnitine consumption caused the higher glucose and lower abdominal fat in comparison to control (p<0.05). CONLUSIONS: Totally, the results of recent experiment show that consumption of 300 mg/kg L-carnitine improves the performance of broiler chickens through the increase in dietary fatty acids and energy.


Barker, D.L., Sell, J.L. (1994) Dietary L-carnitine did not influence performance and carcass composition of broiler chickens and young turkeys fed low or high fat. Poult Sci. 73: 281-7.
Biber, L. (1988) Carnitine. Ann Rev Biochem. 57: 261-283.
Bish, C.L., Beans W.L., Ruszler P.L., Cherry J. A. (1985) Body weight influence on egg production. Poult  Sci. 64: 2259-2262.
Borges, S.A., Fischer Da Silva, A.V., Majorka, A., Hooge, D.M., Cummings, K.R. (2004) Physiological responses of broiler chickens to heat stress and dietary electrolyte balance (sodium plus potassium minus chloride, miliequivalents per kilogram). Poult  Sci. 83: 1551-1558.
Borum, D.R. (1983) Carnitine. Ann Rev Nutr. 3: 233-259.
Bremer, J. (1983) Carnitine: metabolism and functions. Physiological  Rev. 63: 1420-1480.
Cartwright, A, L. (1986) Effect of carnitine and dietary energy concentration on body weight and body lipid of growing broilers. Poult Sci. 65: 21-29.
Celik, L., Ozturkcan, O., Inal, T.C., Canacankatan, N., Kayrin, L. (2003) Effect of L-carnitine and niacin supplied by drinking water on fattening performance, carcass quality and plasma L-carnitine concentration of broiler chicks. Archiv Tierenahr. 57: 127-136.
Cooper, M.A., Washburn, K.W. (1998) The relationships of body temperature to weight gain, feed consumption, and feed utilization inbroilers under heat stress. Poult Sci.77: 237-242.
Corduk, M., Ceylan, N., Ildiz, F. (2007) Effects of dietary energy density and L-carnitine supplementation on growth performance, carcass traits and blood parameters of broiler chickens. S Afr J Anim Sci. 37: 65-73.
Darryl, L., Barker, D.L., Jerry, L., Sell, J.L. (1994) Dietary carnitine did not influence performance and carcass composition of broiler chickens and young turkeys fed low- or high– fat diets. Poult Sci. 73: 281-287.
Donkoh, A. (1989) Ambient temperature: a factor affecting performance and physiological response of broiler chickens. Int J Biometeor. 33: 259–265.
Esteva-Garcia, E., Mack, S. (2000) The effect of DL-methionine and betaine on growth performanceand carcass characteristics in broilers. Anim Feed Sci Technol. 87: 151-159.
Iwaga mi, Y. (1996) Changes in the ultrastructure of human cells related to certain biological responses under hyperthermic culture conditions. Human Cell. 9: 353.
Kita, K., Kato, S., Aman, M., Okumura, J., Yokota, H. (2002) Dietary L-carnitine increase plasma insulin like growth factor I- concentration in chicks fed a diet with adequate dietary protein level. Br Poult Sci. 43: 117-121.
Leibetseder, J. (1995) Studies on the effects of L-carnitine in poultry. Anim Nutr. 48: 97-108.
Lien, T.F., Horng, Y.M. (2001) The effects of supplementary L-carnitine on the growth performance, serum components, carcass traits and enzyme activities in relation to fatty acid β-oxidation of broiler chickens. Br Poult Sci. 42: 92- 95.
Mahmoud, H., Rabie, M.H., Szilagyi, M. (1998)Effects of L-carnitine supplementaion of diets deffering in energy levels on performance, abdominal fat countent, and yield and composition of edible meat of broilers. Br J Nutr. 80: 391-400.
Mast, J., Buyse, J., Goddeeirs, B.M. (2000) Dietary L-Carnitine supplementation increases antigenspecific immunoglobulin G production in broiler chickens. Br J Nutr. 83: 161-6.
Miah, M.Y., Rahman, M.S., Islam, M.K., Monir, M.M. (2004) Effects of saponin and L-carnitine on the performance and reproductive fitness of male broiler. Int J Poult Sci. 3: 530- 534.
Morêki, J.C. (2008) Feeding strategies in poultry in hot climte. Poultry Today. 601: 1-5. 
Mujahid, A., Yoshiki, Y., Akiba, Y., Toyomizu, M. (2005) Superoxide radical production in chicken skeletal muscle induced by acute heat stress. Poult Sci. 84: 307-314.
Nguyen, T.V., Bunchasak, C. (2005) Effects of dietary protein and energy on growth performance and carcass characteristics of Betong chicken at early growth stage. Songklan J Sci Technol. 27: 1171-1178.
Pourreza J., Sadegi G.A., Mehri, M. (2008) Scott’s Nutrition of the Chicken. Leeson, S., Summers, J.D. (eds.). (3rd ed.) Arkan Danesh Publication, Esfahan, Iran.
Rabie, M.H., Szilagyi, M. (1998) Effects of L-carnitine supplementation of diets differing in energy levels on performance, abdominal fat content, yield and composition of edible meat of broilers. Br J Nutr. 80: 391–400.
Rabie, M.H., Szilagyi, M., Gippert, T., Votisky, E., Gerendai, D. (1997) Influence of dietary L-carnitine on performance and carcass quality of broiler chickens. Acta Biol Hung. 48: 241-252.
Sarica, S., Corduk, M., Kilinc, K. (2005) The effect of dietary L-carnitine supplementation on growth performance, carcass traits and composition of edible meat in Japanese quail. J Appl Poult Res. 14: 709-715.
Smith, M.O., Teeter, R.G. (1987) Potassium balance of the 5 to 8 week old broiler exposed to constant heat or cycling high temperature stress and the effects of supplemental potassium chloride on body weight gain and feed efficiency. Poult Sci. 66: 487-492.
Taraz, Z., Dastar, B. (2008) Effects of L-Carnitine supplementation in diets with different levels of protein on performance and blood parameters in broiler chickens. J Agric Sci Nat Res. 5:123-114.
Temim, S., Chagneau, A.M., Guillaumin, S., Michel, J., Peresson, R., Geraert, P.A., Tesseraud, S. (1999) Effects of chronic heat exposure and protein intake on growth performance, nitrogen retention and muscle development in broiler chickens. Reprod Nutr Dev. 39: 145-156.
Xu, Z.R., Wang, M.Q., Mao, H.X., Zhan, X. A., Hu, C.H. (2003) Effects of L-Carnitine on growth performance, carcass compositon, and metabolism of lipids in male broilers. Poult Sci. 82: 408- 413.
Young, Z., Qiugang, M., Xiumei, B., Lihong, Z., Qiang, W., Cheng, J., Laiting, L., Haicheng, Y., (2010) Effects of dietary acetyl- L-carnitine on meat quality and lipid metabolism in Arbor Acres broilers. As-Aus J Anim Sci. 23: 1639-1644.