Author
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Allen, Patricia |
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Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 11/7/1995 Publication Date: N/A Citation: N/A Interpretive Summary: Avian coccidiosis has been estimated to cost the American poultry industry about $250 million annually in production losses resulting from morbidity and mortality. An additional cost of $100 million is incurred due to the necessary prophylactic addition of anticoccidial drugs to poultry feed. Over the past several years, the emergence of drug resistant strains of coccidia has posed a threat for increased economic losses. Therefore, alternative methods for control of coccidiosis are being sought. One of these is dietary modulation of infections. We have assessed the effectiveness of dietary induced oxidative stress, as created by the addition of various levels of omega-3 fatty acid (linolenic acid)- rich flaxseed to broiler starter diets, on weight gains and lesion scores in chicks infected with Eimeria maxima. This is a parasite of the mid-small intestine. The flaxseed diets were not effective in reducing lesions caused by E. maxima, in fact, they exacerbated them at higher parasite doses. These results are in contrast to the effective control of such diets on infections caused by the cecal parasite, E. tenella. The results clearly show that the effects of dietary-induced oxidative stress on coccidiosis is dependent upon the species of parasite, and its location within the host. Technical Abstract: Two experiments were run to determine effects of starter diets containing omega-3 fatty acids from flaxseed on the performance of young broiler chicks during coccidia infections. In the first experiment, diet supplementation with 15% whole flax seed significantly reduced weight gain of chickens infected with E. tenella or E. maxima whereas a diet supplemented with 5% menhaden oil did not. Supplementation with 5% menhaden oil or 15% whole flaxseed significantly reduced lesions caused by E. tenella, but had no effect on lesions caused by E. maxima. In a second experiment, diets supplemented with 5% or 10% ground flaxseed were assessed for effects on the performance of chicks infected with three dose levels (500, 5,000 or 50,000 oocysts) of E. maxima. Neither flaxseed diet protected weight gain during infection with 50,000 oocysts. However, a 5% flax diet protected weight gains in chicks infected with 500 or 5,000 oocysts. Diets supplemented with both 5% and 10% flaxseed exacerbated lesions in chicks infected with 5,000 or 50,000 E. maxima oocysts compared to the control diet. Thus diets containing high amounts of omega-3 fatty acids do not affect the development of all Eimeria sp. in the same manner. |
