Observations on the gross pathology of Eimeria praecox infections in chickens.

Challenge infections with 10(3), 5 x 10(4), 10(5), or 5 x 10(5) sporulated Eimeria praecox oocysts caused moderate but significant weight gain reduction at all infective doses. Substantial reduction in plasma carotenoids and moderate but significant increases in plasma NO2(-) + NO3- were observed only at the two higher doses when measured at day 6 postchallenge (PC). Daily monitoring of chickens after challenge with 5 x 10(4) oocysts revealed an inflammatory response in the duodenum and jejunum beginning at day 1 PC that was associated with a significant increase in levels of plasma NO2(-) + NO3-, which peaked at day 4 PC. A moderate, uniform hyperplasia of the small intestine and significant depression of plasma carotenoids were observed on days 4-6 PC. Plasma NO2(-) + NO3- decreased to control levels by day 6 PC. All infections were accompanied by production of a mucoid exudate in the duodenum and jejunum, which became thick and opaque by 4 days PC and tended to obscure mildly inflamed areas. These observations indicate that the acute host response to primary infection with E. praecox is both different from and occurs earlier than the response to experimental infections with other Eimeria spp., such as Eimeria acervulina, Eimeria maxima, or Eimeria tenella. These factors need to be considered in observations of pathology arising from co-infections of E. praecox with other Eimeria species, especially in drug sensitivity testing of Eimeria oocysts recovered from litter and in the evaluation of live oocyst vaccines.

Dietary modulation of avian coccidiosis.

During the past several years, our laboratory has been investigating the anticoccidial activities of various natural products that have potential use as dietary supplements for coccidiosis control. Sources of fats containing high concentrations of n-3 fatty acids such as menhaden oil and flaxseed oil and flaxseed, when added to starter rations and fed to chicks from one day of age, effectively reduce lesions caused by the caecal parasite Eimeria tenella, but not lesions caused by Eimeria maxima. Our results are consistent with reports of effects of diets high in n-3 fatty acids on other protozoan parasites which suggest that the state of oxidative stress induced by these diets in the cells of both host and parasites is responsible for their parasitic actions. Artemisinin, a naturally occurring (Artemisia annua) endoperoxide and effective antimalarial significantly lowers lesions from E. tenella when given at low levels as a feed additive. The mechanism of its action is also considered to involve induction of oxidative stress. Diets supplemented with 8 p.p.m. gamma-tocopherol (abundant in flaxseeds) or with 1% of the spice tumeric, reduce mid-small intestinal lesion scores and improve weight gains during E. maxima infections. These compounds may exert their anticoccidial activity because they are effective antioxidants. Betaine, a choline analogue found in high concentrations in sugar beets, improves nutrient utilisation by animals under stress. When provided as a dietary supplement at a level of 0.15% it has enhanced the anticoccidial activity of the ionophore, salinomycin. Betaine may act as an osmoprotectant whereby it improves the integrity and function of the infected intestinal mucosa. In in vivo studies, betaine plus salinomycin significantly inhibit invasion of both E. tenella and E. acervulina. However, subsequent development of E. acervulina is inhibited more effectively with this combination treatment than development of E. tenella.

The effect of Eimeria acervulina infection on plasma lipids and lipoproteins in young broiler chicks.

In young broiler chicks inoculated with 2 x 10(6) sporulated oocysts of Eimeria acervulina per bird, total plasma lipids were significantly depressed compared with controls in the first week after inoculation. The lowest level observed was at 5 days post-inoculation (d.p.i.), at which time the chick host is known to experience malabsorption in the chick host (Ruff and Wilkins, 1980). Analysis of plasma components of infected chicks at 4 and 7 d.p.i. showed that triglycerides, total cholesterol, free fatty acids, pigments and total protein were significantly decreased compared with controls. At 7 d.p.i., reduction of total cholesterol reflected mainly reduction in high density lipoprotein (HDL) cholesterol. However, the ratio of HDL cholesterol/total plasma cholesterol was not significantly different from the control ratio. Density gradient ultracentrifugation of chick plasma separated lipoproteins into three main fractions: portomicrons plus very low density lipoproteins (PM + VLDL), low density lipoproteins (LDL) and HDL. These fractions were analyzed for lipid content. Infection with E. acervulina caused (1) significant reduction in the triglyceride and cholesterol contents of the PM + VLDL fraction at 3 and 5 d.p.i., (2) significant reduction of LDL cholesterol at 9 d.p.i. and LDL phospholipid at 5-9 d.p.i., and (3) significant reduction of HDL cholesterol at 3-9 d.p.i. and HDL phospholipid at 5-9 d.p.i. Starvation of uninfected chicks for 48 h caused significant reduction in plasma triglycerides and phospholipids, but an increase in total cholesterol. Density gradient ultracentrifugation showed that the changes in these components reflected mainly reduction of the lipids in the PM + VLDL fraction. The LDL fractions, however, appeared more intense than those of the controls and contained more cholesterol and phospholipids. These results suggest that changes at 3 and 5 d.p.i. in the plasma lipoprotein pattern of chicks infected with E. acervulina most closely resemble changes seen in chicks starved for 48 h as far as PM + VLDL fraction is concerned. However, changes seen from 7 to 9 d.p.i. involve the LDL and HDL fractions and may reflect alterations in lipid and/or lipoprotein synthesis in the liver and intestine.

Changes in liver glycogen of broilers during coccidiosis.

Liver glycogen levels of broilers with Eimeria acervulina, E. Brunetti, or E. tenella fell during the acute phase of the infection with the maximum effect at 5-6 days post-inoculation (DPI). During the early recovery phase (6-8 DPI), liver glycogen levels in the E. acervulina-infected birds increased to levels up to 3 times greater than those found in uninoculated control birds. A lesser increase was occasionally seen in E. tenella-infected birds. Pair feeding studies showed that the decrease in liver glycogen was not related to the amount of feed consumed. The magnitude of the glycogen overshoot at 7 DPI was not related to the depression of weight gain at 5 and 6 DPI. When feed was withheld from birds, liver glycogen levels of uninoculated control birds fell rapidly within 1 h after feed withdrawal. In birds infected with E. acervulina, liver glycogen levels remained high even after 3 h starvation. Injection of glucagon indicated that glycogen could be mobilized in both infected and uninfected birds.

The effects of Eimeria acervulina infection on the metabolism of chick duodenal tissue.

Broiler chicks, 2--3 weeks old were infected with eimeria acervulina, and the metabolism and ultrastructure of the infected duodenal tissue were studied during the period 3--14 days after inoculation (DAI). Between 4 and 5 DAI duodenal rings showed an increase in C-1/C-6 ratios of CO2 evolved from glucose as well as decreases in the rates of oxidation of glucose and octanoic acid. Between 4--7 DAI mitochondria from infected epithelial layers had reduced rates of octanoic acid and alpha-ketoglutaric acid oxidation as compared to controls. Electron microscopic observations confirmed the biochemical findings. At 5--6 DAI mitochondria in many uninfected cells were progressively swollen and then vacuolated as the cristae appeared to break down. Mitochondria in cells which contained parasites did not show these changes.

Effect of virginiamycin on serum carotenoid levels and long, segmented, filamentous organisms in broiler chicks.

Virginiamycin (Stafac 20) was mixed with feed at three levels recommended for chickens--5.5, 11, and 22 mg/kg (respectively 5, 10 and 20 g/ton)--and fed to broiler chicks. When fed from 1 day through 2 weeks of age, the drug appeared to retard infection of the lower small intestine by long, segmented, filamentous organisms (LSFOs), and at 2 weeks of age serum carotenoids in treated chicks were significantly higher than levels found in unmedicated chicks. However, as chicks were grown out to 4 and 6 weeks of age, the drug did not completely prevent eventual LSFO infection, even at the highest dose, and mean serum carotenoid levels in treated chicks were not significantly different from levels in control chicks. However, chicks fed at the level of 22 mg/kg had fewer LSFOs. Withdrawal of virginiamycin from treated chicks at 4 weeks of age allowed LSFO infection to occur but did not significantly affect serum carotenoid levels. When the drug was fed for 2 weeks at 22 mg/kg to 2-week-old chicks already infected with LSFOs, the bacteria could no longer be detected, suggesting that virginiamycin may aid the natural decline in LSFO population. Coincident with this treatment, serum carotenoids were higher, but not significantly so. Virginiamycin did not significantly increase the mean body weights of chicks in any of these experiments.

The effect of Eimeria acervulina infection on hearts of young broiler chicks.

Hearts from 2-to-3-week-old broiler chicks that were inoculated with 2 X 10(6) sporulated oocysts/bird weighed significantly less than hearts from control chicks at 4 and 7 days postinoculation (PI). However, heart weights of infected chicks expressed as percentage of body weights were not significantly different from those of controls throughout the experiment. Infection also had no significant effect on heart protein content. Cardiac glycogen was significantly increased at 7 days PI but not at 4 days PI. Oxidation of both alpha-ketoglutaric and octanoic acids by mitochondrial preparations from hearts of infected chicks was significantly depressed at 4 days PI compared with controls; at 7 days PI, however, oxidation of octanoic acid was significantly increased, but that of alpha-ketoglutaric acid was not.

Physiological responses of chicken gut tissue to infection with Eimeria acervulina.

Although Eimeria acervulina parasitizes primarily the duodenum of chickens, in heavy infections the entire small intestine may become distended. This reaction was measured in terms of length, fresh weight, dry weight, and moisture in relation to time postinfection (PI) and dose. Increases in percent moisture were apparently associated with numbers of infection sites, because higher doses caused increased moisture in the more distal portions of the small intestine. The first gross intestinal response to infection with 2 X 10(6) sporulated oocysts (SO)/bird was an increase in ileal length at 4 days PI. This response was followed by increases in fresh weight and dry weight by 7 days PI. At 7 days PI, inoculation with 10(4) and 10(5) SO/bird was associated not only with increases in fresh and dry weights of ileal segments but with those of jejunal segments as well. Infection with 10(6) SO/bird apparently caused sufficient increases in jejunal infection sites to overcome the hypertrophy or hyperplasia seen at lower doses. At 7 days PI, more mucosal cells could be scraped from ileal segments from infected chicks than from controls. Whole cells, as well as mitochondrial preparations of these cells, oxidized octanoic acid at higher rates than did controls. It is suggested that increased mass and metabolic activity of the more distal portions of the small intestine provide a means for compensatory absorption of nutrients during E. acervulina infection.

Genetic influence on nitric oxide production during Eimeria tenella infections in chickens.

Studies were carried out to assess the importance of nitric oxide (NO) production in vivo in resistance to Eimeria tenella infections through treatment of resistant SC and susceptible TK strains of chickens with compounds proven to be effective inhibitors of induced nitric oxide synthase. The SC strain produced higher levels of plasma NO2- + NO3- in response to primary infection than did the TK strain. SC chickens were also more responsive in reduction of NO2- + NO3- levels and increased oocyst output in response to treatments with S-methylisothiourea or NG-methyl-L-arginine (LNMA) during primary infection. However, the SC strain, regardless of drug treatment, consistently yielded higher oocyst output during primary infection, indicating it could be susceptible to a higher parasite burden. On the other hand, the SC strain seemed to develop immunity more rapidly than the TK strain, in that oocyst output was decreased in both untreated and LNMA-treated chicks upon challenge infection compared with that of the TK strain. Oocyst output from both SC and TK strains was further decreased by LNMA treatment during challenge infection rather than increased, suggesting minimal involvement of NO production in the immune response to challenge. These results indicate that NO production during primary E. tenella infection may be only one of several immune responses and may not be the main anticoccidial effector.

Development of a protective index to rank effectiveness of multiple treatments within an experiment: application to a cross-protection study of several strains of Eimeria maxima and a live vaccine.

Vaccination of chickens with live oocysts has become a more widely used method for controlling avian coccidiosis as resistance to anticoccidial medication increases. However, some coccidia strains are not useful in multispecies vaccines because antigenic variation has made them generally less protective. In order to experimentally test a number of strains for the best cross protection, we have devised an evaluation method using four independently measured variables: weight gain, lesion score, plasma carotenoids, and plasma NO2- + NO3-. These values, when measured at 6 days postchallenge, tend to be significantly correlated. A protective index (PX) is calculated for each chicken using the following algorithm: PX = (Ngain + Ncarotenoids) - (Nsqrls + N[NO2- + NO3-]), where the prefix N indicates values for a variable normalized against a mean of that variable from a control group. Nsqrls values are normalized values of the square roots of lesion scores. The PX can then be treated as a dependent variable. In this study, mean PX values of unchallenged groups cluster around 0. Mean PX values of protected chickens are statistically close to those from unchallenged groups, whereas unprotected chickens have highly negative mean PX values.

Eimeria acervulina infection elevates plasma and muscle 3-methylhistidine levels in chickens.

To assess muscle breakdown during avian coccidiosis, the level of the nonmetabolizable amino acid 3-methylhistidine (3MH) was determined in muscle, plasma and excreta from chickens infected with Eimeria acervulina. The changes in 3MH levels during infection were assessed at 1-29 days postinoculation (DPI) in animals given 5 x 10(5) oocysts per bird. The effect of levels of parasitism were evaluated at 8 DPI in birds receiving 5 x 10(3), 5 x 10(4), 5 x 10(5) or 1 x 10(6) oocysts each. The 3MH levels of plasma, muscle, and excreta samples were determined by high-pressure liquid chromatography after derivatization with fluorescamine. Weight gains, breast muscle weight, eviscerated weight, plasma carotenoid levels, dry weight of muscle, and gross lesion scores were also determined. Infected birds had significantly elevated plasma and muscle 3MH at 4 and 8 DPI following a single dose of E. acervulina. The increase in 3MH levels had an inverse relationship with the time course of weight gain and plasma carotenoid levels. Plasma and muscle 3MH levels returned to control values by 15 DPI and remained unchanged from control values through the remainder of the experiment (29 DPI). Breast weight was decreased in infected birds, but the ratio of breast weight to eviscerated body weight was unchanged. Excretion of 3MH decreased relative to controls at 4 and 8 DPI and returned to control levels on 15 DPI. The plasma and muscle levels of 3MH were related to severity of infection; however, levels of excreted 3MH were not. The results suggested that muscle breakdown, as assessed by plasma and muscle levels of 3MH, increased during the acute stage of E. acervulina infection. The underlying causes for this muscle breakdown was unclear but could involve a physiological response to anorexia and decreased food intake during the acute phase of infection. Levels of excreted 3MH did not increase during infection and this may be the result of decreased excreta output during infection. Plasma and muscle levels of 3MH were correlated with severity of E. acervulina infections but may not be as sensitive an indicator of infection as plasma carotenoid levels or other physiological parameters.

An evaluation of Debrisan in chronic leg ulcers and pressure sores.

Debrisan (Dextranomer) was subjected to a simple open assessment in the treatment of fifty-three chronic leg ulcers and thirty pressure sores in eight hospitals. It was found that 70% of leg ulcers and 76% of pressure sores improved, with a noticeable cleansing effect being evident in 79% and 83% respectively. No side-effects were recorded.

Clinical chemistry of anaplasmosis: blood chemical changes in infected mature cows.

The clinical chemical changes induced by Anaplasma marginale infection were determined in 16 adult, intact cows infected with either of 2 virulent isolates and in 8 others treated with a live sheep-attenuated A marginale vaccine and were compared with the clinical chemical analyses in 7 noninfected controls. Blood samples from the cows were analyzed for various serum components and during clinical disease. Cows infected with the 2 virulent isolates had maximum erythrocyte parasitemias (0.5% to 66%) between 1 and 11 days of patency (DP); 7 of the 16 infected animals died within 5 to 12 DP. Cows given the sheep-attenuated anaplasma vaccine had maximum parasitemias (0.1% to 4.2%) between 1 and 16 DP and none died. Infection with the virulent isolates produced severe anemia (mean RBC count = about 2 million/mm3) and caused increases in serum total bilirubin (TBILI), direct bilirubin (DBILI), serum urea nitrogen (SUN), alkaline phosphatase (ALP), and serum aspartate aminotransferase (AST) that were significantly higher than comparable changes in control values. These increases were highest after peak parasitemias in surviving animals. Vaccination with the attenuated isolate produced a mild anemia (mean RBC count = about 5 million/mm3) and a significant increase only in ALP. Marked increase in TBILI, DBILI, SUN, ALP, and AST were detected 0 to 1 day before death in 3 cows. However, such increases were not observed 2 to 4 days before death in the other cows that died.

Clinical chemistry of anaplasmosis: comparative serum protein changes elicited by attenuated and virulent Anaplasma marginale isolates.

In a comparative study of the clinical chemical changes during Anaplasma marginale infection, 16 intact mature cows were infected with either of 2 virulent isolates. Eight others were treated with a live A marginale vaccine (sheep-attenuated) and 7 were maintained as controls. Before and during patency, samples of blood from the cows were analyzed for total WBC, parasitemia, card test titer (CTT), total protein, albumin, and globulin fractions. In the cows inoculated with virulent isolates, albumin was significantly depressed throughout patency, whereas gamma-globulins and WBC were increased after peak parasitemia, as well as during recovery. The CTT was highest immediately after peak parasitemia. A significant increase was not observed in beta-globulin. Seven of the 16 infected cows died, but no consistent patterns of change in serum protein fractions or WBC could be associated with mortality. The 8 cows vaccinated with the attenuated isolate showed a significant mean decrease in albumin throughout patency, but no significant mean increase in alpha- or beta-globulin. A mean increase in gamma-globulin was observed only during the recovery period. The CTT increased gradually throughout patency, peaking during the recovery period. A significant mean increase over control in WBC count was observed only during rising parasitemia.

Effect of antiparasitic medication in ponies on pasture.

Twenty Shetland ponies, 6 to 7 months old, were naturally infected with gastrointestinal nematodes and stomach bots. The ponies were allotted to 2 groups of 10 and were maintained on separate similar pastures that were free of infective larvae at the beginning of the study. The ponies in 1 group were treated monthly for 17 months with a therapeutic dose of a thiabendazole and piperazine mixture; those in the other group were not treated. During the 3rd and 5th months of the experiment, the ponies in the treated group were also given therapeutic doses of dichlorvos to remove bots. Various physical, hematologic, parasitologic, and blood chemical observations were made at weekly intervals. Each group of ponies was weighed at biweekly intervals. At the end of the experiment, the greatest differences between the treated and control ponies were in the mean number of worm eggs in fecal samples (0 vs 1,866 eggs/g), mean body weight (151.9 vs 117.0 kg), mean heart girth (126.5 vs 116.3 cm), mean packed cell volume (36.4 vs 30.8%), and mean serum protein content (8.47 vs 9.33 mg/100 ml), especially beta-globulin content (mean of 1.9 vs 3.4 mg/100 ml). The treated ponies remained clinically normal and were more spirited and more difficult to restrain for blood sampling and weighing than were the untreated controls. Parasitic nematode larvae were not recovered from grass samples from the pasture grazed by the treated ponies, but many such larvae (up to 500/300-g sample) were recovered from grass samples from the pasture grazed by the untreated ponies.

Effects of formaldehyde fumigation of housing on carotenoid pigmentation in three breeds of chickens.

Three breeds of chickens (two broiler breeds, A and B, and one layer breed, C) were raised from 1 day to 3 wk of age in either standard housing or housing additionally fumigated with formaldehyde. Groups of chicks from each breed in both housings received either regular poultry starter ration or this ration supplemented with marigold meal. At 3 wk of age, chicks of all three breeds had higher (111, 113, and 115%) mean body weights when raised in fumigated housing. There was no significant effect of supplemental carotenoids on body weight. Chicks of all three breeds raised in fumigated housing had significantly higher plasma carotenoid concentrations when fed either regular or supplemented feed, and, with the exception of Breed A on regular feed, also had significantly increased skin carotenoid values. No significant differences among breeds in plasma or skin carotenoid values were seen in chicks fed regular ration. However, significant differences were seen among groups of chicks fed supplemental carotenoids. The layer breed, C, had the highest percentage increase in carotenoid pigmentation when fed the carotenoid-supplemented diet in fumigated housing.

Nitric oxide production during Eimeria tenella infections in chickens.

The objective of this study was to gather evidence for production of nitric oxide (NO) during a primary infection with the protozoan parasite Eimeria tenella, which carries out its life cycle in the ceca of chickens. Relationships of plasma levels of NO2(-)+NO3-, stable metabolites of NO, with parasite dose and with time after infection were examined, as well as effects of administration of aminoguanidine, an inhibitor of induced nitric oxide synthase (iNOS). Inoculation with 5 x 10(4) and 1 x 10(6) but not 1 x 10(3) oocysts per chick caused significant (P < or = 0.05) increases in micromolar concentrations of plasma NO3(-)+NO3- when measured at 7 d postinoculation (PI). In chickens inoculated with 5 x 10(4) oocysts, significant (P < or = 0.05) increases in plasma NO2(-)+NO3- were seen at 5 and 7 but not 3 d PI. Daily intraperitoneal administration of 1.25 mg per chick aminoguanidine during the period of infection did not lower the increases in plasma NO2(-)+NO3- seen at 5 and 7 d PI, and did not affect the degree of colonization of the cecal tissue by the parasite. However, administration of aminoguanidine did alter the gross appearance of the ceca, which were less swollen and filled with blood at 5 and 7 d PI as compared with ceca from untreated chickens. Hemorrhage is a major pathological manifestation of E. tenella infections, associated with the disruption of the cecal mucosa by the developing parasite. The results of this experiment are consistent with the hypothesis that an aminoguanidine-inhibitable NO synthase, perhaps in the vascular endothelium of the cecal blood vessels, may contribute to hemorrhage by causing vasodilation.

Production of free radical species during Eimeria maxima infections in chickens.

Five experiments were conducted to investigate the production of nitric oxide (NO) and superoxide anion (O2-) during infections of chickens with the coccidial parasite, Eimeria maxima, in order to assess the importance of these free radical species in the pathogenesis of the infections. Nitric oxide production was estimated by analyzing NO2(-)+NO3-, stable metabolites of NO, in the plasma and intestinal mucosa. The potential for O2- production was estimated from activities of beta-nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in mucosal homogenates. Levels of NO2(-)+NO3- reached maximum values at about 6 d postinoculation, a time when mucosal damage was high and oocysts were being shed. The activity of NADPH oxidase in infected mucosa was also increased. Thus, at that time, there was a potential for oxidative destruction of mucosal tissue from these free radicals and their reaction products. Levels of NO2(-)+NO3- did not increase in a stepwise manner with increasing infective dose, suggesting that production of NO may be regulated post-transcriptionally by other factors elaborated by the immune response to infection, or may be controlled by substrate limitations. A comparison of two E. maxima strains indicated that the virulence of a strain was not directly related to NO production. Increased production of O2- due to increased NADPH oxidase activity during infection may cause a reduction in levels of carotenoid pigments that is unrelated to malabsorption.

Long segmented filamentous organisms in broiler chicks: possible relationship to reduced serum carotenoids.

Over the past several years, broiler-flocks at the author's laboratory have exhibited low serum carotenoid levels. This phenomenon has not been related to exceptionally low carotenoids in the feed or to known protozoan or viral infections. However, long segmented filamentous organisms (LSFO) have been identified in the pale chicks. An inverse correlation between LSFO counts and serum carotenoid levels was not observed, but prevention of LSFO infection consistently resulted in higher carotenoid values. Young chicks were very susceptible to naturally acquired LSFO infection, but the organisms decreased in number with time and became very difficult to find by the time the chicks were 7 wk old. Segments of LSFO containing endospores were detected in mucosal smears. This observation, along with the extreme ease of natural infection, suggests that LSFO are transmitted by dust-borne spores. Transmission can be prevented by fumigation of housing with formaldehyde vapors.

Effect of coccidiosis on the distribution of dietary lutein in the chick.

A series of experiments was run to determine whether the distribution of dietary carotenoids in chick plasma and tissue was dependent upon a saturable carrier, and to observe how infection with Eimeria acervulina affected this distribution. Broiler (Hubbard x Hubbard) and Sex Sal (Rhode Island Red x White Rock) chicks were fed a white corn and soybean meal-based diet supplemented with varying levels of a commercial lutein concentrate. Plasma, small intestine, and liver were analyzed for lutein. In the first experiment, mean plasma values in control broiler chicks increased linearly from 0 to 200 ppm supplementation. Mean plasma values of infected chicks were decreased an average of 71% as compared with controls, and reached a plateau between 100 and 200 ppm dietary lutein. In the second experiment, plasma, small intestinal, and liver lutein levels in broiler chicks reached a plateau between 200 and 500 ppm. In the third experiment, plasma and liver values in Sex Sal chicks leveled off between 250 and 500 ppm whereas levels in the small intestine increased linearly. Infection of the Sex Sal chicks at 3 wk of age with E. acervulina caused plasma lutein levels to be reduced about 88%, small intestinal levels 76%, and liver levels 72%. Supplementation with 500 ppm resulted in higher proportions of lutein in tissues. Infection with E. acervulina shifted the ratios to even higher proportions in the tissues at all supplementation levels.(ABSTRACT TRUNCATED AT 250 WORDS)