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Coccidiosis is one of the most prevalent diseases in poultry. The objective of the current study was to determine the effects of floor heating when poults were artificially infected with Eimeria regarding the outcome of the infection and secondary effects on litter quality and health of the foot pad. Two trials were performed. In each trial, 4 groups of 2-wk-old turkeys were reared for a 4-wk period. All birds were fed ad libitum identical pelleted diets without any anticoccidial additive. The first 2 groups were housed on dry wood shavings, with and without floor heating; the other 2 groups were housed on wet wood shavings (35% moisture, achieved by adding water as required), with and without floor heating. Two birds only (primary seeder birds; the other 18 birds were nominated as secondary infected birds) in each of the 4 groups were experimentally infected orally with Eimeria adenoeides (˜50,000 oocysts/bird). The number of oocysts eliminated via excreta was determined repeatedly. On d 42, each bird not only was scored macroscopically for coccidial lesions in the cecum but also oocyst counts were determined in the cecal contents. Finally, the foot pads were assessed weekly for external scoring and on d 42 of life for histopathological scoring. Although the counts of oocysts in seeder birds were almost identical (d 6 postinoculation), oocyst counts in excreta of secondary birds were markedly reduced in both trials when the poults were not exposed to wet litter. Moreover, in both trials using floor heating with exposure to wet litter resulted in a higher oocyst count in the excreta of secondary infected birds (3.72/3.92 in trials 1 and 2) on d 24 postinoculation compared with the other groups. Using floor heating resulted in significantly decreased foot pad dermatitis scores compared with groups housed without floor heating. In conclusion, the differences in oocyst counts indicate that the process of sporulation is affected by both the moisture and the temperature of the litter.

An effective method for the enrichment of two cecal species of the avian Eimeria in mixed cultures has been developed. The method involves the transfer of sporozoites of Eimeria tenella and Eimeria adenoeides from their specific site of invasion in a foreign host bird to the natural host, and markedly increases the numbers of the cecal species in relation to the other species in the mixture. Donor turkeys and chickens were inoculated with mixed cultures containing equal numbers of oocysts of the chicken coccidia, E. tenella + Eimeria acervulina, or the turkey coccidia, E. adenoeides + Eimeria meleagrimitis, respectively. After 8 to 24 h, the cecal tissues of the donor birds were scraped into phosphate-buffered saline and transferred, per os, to the natural host. On Day 6 to 7 posttransfer, numerous oocysts of E. tenella and E. adenoeides were found in the ceca of the recipient chickens and turkeys, respectively. In contrast, only occasional oocysts were found in a few birds in other areas of the intestine.

Plasma epinephrine, norepinephrine, and glucose levels were measured in 3- to 4-wk-old turkey poults that had been infected with the coccidium Eimeria adenoeides. When measured at 6 days postinoculation, the acute stage of the infection, the epinephrine and norepinephrine levels of the infected poults showed a dose-dependent increase over levels in controls, with poults that were most heavily infected having the highest levels. The catecholamines appeared to show a classic stress-elicited response: this response increases with time to high levels during the acute stage of the infection, and then returns to levels approximately the same as those of the controls as the poults recover from the infection. Anorexia, or feed restriction, appeared to be primarily responsible for the increase in norepinephrine. However, epinephrine levels in the infected poults were significantly higher than in their pair-fed, uninfected counterparts, indicating that factors other than reduced feed consumption contributed to the increase. The data indicate that plasma catecholamines are increased during coccidial infection. As pressor compounds, they may contribute to the previously observed changes in blood pressure and heart function in infected poults.

Three-week-old turkey poults receiving 250 μg/kg of dietary aflatoxin displayed prolonged prothrombin times due to decreased fibrinogen levels and depressed activity of factor II. Decreased body weights and increased mortality were also evident. Poults experiencing an Eimeria adenoeides infection had slightly increased prothrombin times that were not corrected by the addition of specific clotting factors. These birds exhibited significant reductions in total plasma protein levels. The combination of E. adenoeides and aflatoxicosis resulted in a significant depression in body weight, altered prothrombin time, and decreased levels of plasma calcium, protein, and fibrinogen. Increased mortality was also observed. E. adenoeides did not affect the hemostatic system of the turkey as severely as does aflatoxin. Turkeys were shown to be highly susceptible to aflatoxin when compared to chickens.

Halofuginone was tested at 0, 1.5, 3.0, or 6.0 ppm in the feed against single and mixed infections of recent field isolates of Eimeria adenoeides, E. meleagrimitis, and E. gallopavonis. Severe infections were produced in unmedicated, infected controls. Weight gains were significantly improved by 1.5 or 3 ppm of halofuginone, and intestinal lesion scores and fecal droppings scores were greatly reduced. Oocyst shedding was reduced 91 to 100% by halofuginone treatments. Treatment with 6 ppm of halofuginone gave good protection but appeared to depress weight gains slightly. Treatment with 3 ppm was optimal for the control of all species of coccidia and for optimum performance.

TO DATE six species of coccidia affecting the turkey have been described. They are Eimeria meleagridis, Eimeria meleagrimitis, and Eimeria dispersa described by Tyzzer (1929), Eimeria gallopavonis described by Hawkins (1950), and Eimeria adenoeides and Eimeria innocua isolated and identified by Moore and Brown (1951 Moore and Brown (1952). It is the purpose of this paper to report upon another new species of turkey coccidia. The exact origin of this species is not known since it was obtained from a mixed culture collected by Dr. Philip Hawkins possibly prior to 1950. When Dr. Hawkins discontinued his studies with turkey coccidia his entire collection was turned over to the authors. In one culture labeled E. gallopavonis was found a subspherical type which contained no refractile body. Subsequent investigation of this type definitely indicated that it represented a new species for which the name of Eimeria subrotunda is proposed. A complete description has already been …

Electrophoretic separation of serum proteins of Eimeria-infected turkeys showed five major fractions with significant decreases in albumin levels and significant increases in the alpha 2- and gamma-globulins as compared with controls. The alpha 1- and beta-globulin levels were similar to those of the controls. Significant differences between infected turkeys and uninfected pair-fed controls suggested that protein changes were not solely due to the anorexia associated with Eimeria infections. The increase in alpha 2-globulins was not due to an increase in ceruloplasmin. Indirect fluorescent antibody tests using serum from infected poults as an antibody source were positive, indicating that at least part of the increase in the gamma-globulin fraction was due to the production of immunoglobulins. Electrophoretic separation of plasma lipoproteins showed three to four major bands with a sharp decrease in the portomicrons among infected poults. There was no increase in the pre-beta-lipoproteins (which have the same electrophoretic mobility as the alpha 2-globulins), indicating that the increase in alpha 2-globulins was not due to an increase in the lipoprotein part of this fraction.

Floor-pen studies were conducted in three geographic locations to study the efficacy of halofuginone (3.0 ppm in feed) against important species of coccidia in turkeys. Severe coccidiosis exposure was obtained in studies in Georgia and Colorado and mild coccidiosis in Wisconsin. Coccidiosis caused by contamination of the feed with oocysts of Eimeria adenoeides, E. meleagrimitis, and E. gallopavonis was almost completely controlled by halofuginone at 3 ppm, even though intestinal lesion scores and weight loss were high in two studies. Halofuginone was also highly effective in preventing buildup of infection in pens contaminated by indirect means (movement by caretakers through the pens, etc.). Weight gains and feed conversion were best in poults receiving halofuginone, whether directly or indirectly exposed. There was no evidence that halofuginone caused any untoward reactions in the poults, even though the drug was fed until turkeys reached market weight.