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The eight-week feeding trial was conducted to evaluate the nutrient digestibility and growth performance of broiler chickens fed raw or processed Senna obtusifolia seed meal (SOSM). Six experimental diets were compounded to contain 0% SOSM and 20% each of the raw, boiled, soaked, sprouted and fermented SOSM respectively. Two hundred and sixteen (216) broiler chicks were randomly allotted to six (6) dietary treatments in a randomised complete block design with three (3) replicates containing 12 chicks each. Data were collected on nutrient digestibility, feed intake, weight gain, feed conversion ratio and mortality. The result of productive performance indicated that feed intake, weight gain and feed conversion ratio were significantly (P

Habitat loss and overexploitation extirpated American black bears (Ursus americanus) from most of the Central Appalachians, USA, by the early 20th Century. To attempt to restore bears to the southwestern portion of this region, 2 reintroductions that used small founder groups (n = 27 and 55 bears), but different release methods (hard vs. soft), were conducted during the 1990s. We collected hair samples from black bears during 2004–2016 in the reintroduced Big South Fork (BSF) and Kentucky–Virginia populations (KVP), their respective Great Smoky Mountains (GSM) and Shenandoah National Park (SNP) source populations, and a neighboring population in southern West Virginia (SWV) to investigate the early genetic outcomes of bear reintroduction. Despite having undergone genetic bottlenecks, genetic diversity remained similar between reintroduced populations and their sources approximately 15 years after the founder events (ranges: AR = 4.86–5.61; HO = 0.67–0.75; HE = 0.65–0.71). Effective population sizes of the reintroduced KVP and BSF (NE = 31 and 36, respectively) were substantially smaller than their respective SNP and GSM sources (NE = 119 and 156, respectively), supporting founder effects. Genetic structure analysis indicated that the hard-released (i.e., no acclimation period) KVP founder group likely declined considerably, whereas the soft-released BSF founder group remained mostly intact, suggesting superior effectiveness of soft releases. Asymmetrical gene flow via immigration from the SWV has resulted in the KVP recovering from the initial founder group reduction. Sustained isolation, small NE, and small population size of the BSF may warrant continued genetic monitoring to determine if gene flow from neighboring populations is established or NE declines. For future bear reintroductions, we suggest managers consider sourcing founders from populations with high genetic diversity and soft-releasing bears to locales that are, if possible, within the dispersal capability of extant populations to mitigate the potential consequences of founder effects and isolation.

Summary 1. Animals must move to find food and mates, and to avoid predators; movement thus influences survival and reproduction, and ultimately determines fitness. Precise description of movement and understanding of spatial and temporal patterns as well as relationships with intrinsic and extrinsic factors is important both for theoretical and applied reasons. 2. We applied hidden semi-Markov models (HSMM) to hourly geographic positioning system (GPS) location data to understand movement patterns of the endangered Florida panther (Puma concolor coryi) and to discern factors influencing these patterns. 3. Three distinct movement modes were identified: (1) Resting mode, characterized by short step lengths and turning angles around 180 o ; (2) Moderately active (or intermediate) mode characterized by intermediate step lengths and variable turning angles, and (3) Traveling mode, characterized by long step lengths and turning angles around 0 o . 4. Males and females, and females with and without kittens, exhibited distinctly different movement patterns. Using the Viterbi algorithm, we show that differences in movement patterns of male and female Florida panthers were a consequence of sex-specific differences in diurnal patterns of state occupancy and sex-specific differences in state-specific movement parameters, whereas the differences between females with and without dependent kittens were caused solely by variation in state occupancy. 5. Our study demonstrates the use of HSMM methodology to precisely describe movement and to dissect differences in movement patterns according to sex, and reproductive status.

The effects of polyclonal antisera to 2 recombinant dense granule (DG) antigens of Neospora caninum on invasion and development by N. caninum tachyzoites in baby hamster kidney cell cultures were examined. In immunofluorescent antibody tests, the anti-DG sera, at dilutions of 1:100 to 1:500, reacted intensely with individual intracellular tachyzoites and groups of tachyzoites enclosed in parasitophorous vacuoles at 2 and 52 h p.i., respectively. Tachyzoites suspended in diluted anti-DG sera and inoculated immediately into the cell cultures invaded cells in significantly fewer numbers (53–68% fewer by 2 h p.i.) than tachyzoites suspended in similarly diluted normal rabbit serum. In contrast, tachyzoites suspended in anti-Eimeria tenella sporozoite serum invaded cells as efficiently as those suspended in normal rabbit serum. Addition of anti-DG sera at the time of inoculation of tachyzoites, or to the cell cultures after the parasites had entered cells, had little effect on either the percentage or rate of their subsequent development.

At 7 d postinoculation (DPI) with a mixed culture of avian Eimeria species, 21-d-old chicks maintained in batteries and floor pens on a diet containing 0.15% (3 lb/ton) betaine plus 66 ppm (60 g/ton) salinomycin were significantly heavier and had significantly lower feed conversion ratios and mortality than chicks fed diets containing 0.15% betaine or 66 ppm salinomycin alone, or the control diet. At 31 DPI, when the chicks were 45 d old, the differences between the diet groups were not as great as at 7 DPI. In vitro, except at high concentrations, betaine was nontoxic to sporozoites of Eimeria tenella or Eimeria acervulina and had little effect on their invasion and development in cultured cells. In vivo, invasion by E. tenella and E. acervulina sporozoites was significantly reduced in all chicks fed diets containing betaine or salinomycin compared with that in control chicks. There was a significant interaction between betaine and salinomycin that impacted on invasion by both species. Overall development of E. tenella did not appear to be adversely affected by addition of betaine to diets containing salinomycin. Conversely, development of E. acervulina was reduced in chicks fed diets containing 0.075% (1.5 lb/ton) betaine plus 66 ppm salinomycin as compared with that in chicks fed salinomycin alone.

Freshly excysted sporozoites (SZ) of the turkey coccidia Eimeria meleagrimitis and Eimeria adenoeides were incubated at 41 C in concentrations of monensin from .01 to 1.0 microgram/mL, washed free of the drug, and either processed for phase, fluorescence, and transmission electron microscopy or inoculated into cultures of turkey kidney cells. Phase microscopy indicated that after 1.5 h incubation in 1.0 micrograms/mL monensin, about 60% of the SZ of E. meleagrimitis had become notably rounded or displayed localized protrusions. These alterations were accompanied by ultrastructural abnormalities (in 90% of the SZ) including vacuoles in the cytoplasm, bulging and separation of plasma membrane layers, and dense bands in the refractile bodies that extended toward the periphery of the refractile body. Similar morphological and ultrastructural changes were observed in over half of the E. adenoeides SZ after 2 h incubation in 1.0 micrograms/mL monensin. Additionally, some specimens contained a pycnotic nucleus that was usually surrounded by a large vacuole. After 4 h incubation, almost all of the SZ displayed some degree of ultrastructural damage. Indirect fluorescent antibody labeling with parasite-specific monoclonal antibodies demonstrated clouds of antigen surrounding the monensin-treated but not the untreated SZ, suggesting an increase in permeability with incubation in monensin. With both E. meleagrimitis and E. adenoeides, the structural changes were reflected in a significant inhibition of cellular invasion. The inhibitory activity of monensin was concentration- and time-dependent in that the greatest inhibition of invasion was observed in SZ incubated for 4 h in 1.0 micrograms/mL of monensin; shorter incubation times or lower concentrations of monensin having less effect.

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.

To assess muscle breakdown during avian coccidiosis, the level of the non-metabolizable amino acid 3-methylhistidine (3MH) was determined in muscle and plasma from turkey poults that received an infection with a field isolate containing a mixture of Eimeria species. The effect of increased levels of parasitism was evaluated at 6 days postinoculation (DPI) in birds receiving 2.5 x 10(4), 1 x 10(5), or 2 x 10(5) oocysts each. The changes in 3MH levels during recovery from acute infection were assessed at 6-29 DPI in animals given 1.9 x 10(5) oocysts per bird. In some experiments, uninoculated birds given the same amount of feed as infected birds (pair fed) were used to determine the impact of feed deprivation on weight loss and 3MH levels. Infected birds had significantly elevated plasma and muscle 3MH at 6 DPI after a single dose of Eimeria oocysts. The plasma and muscle 3MH returned to control levels after 14 DPI. The 3MH levels increased with increased dose of oocysts. Plasma and muscle 3MH levels were well correlated, and an inverse curvilinear relationship between weight gain and plasma 3MH concentrations levels was observed. Plasma and muscle 3MH levels were significantly elevated in pair-fed birds, but 3MH levels in infected birds were increased by 30% over pair-fed birds. The results suggested that muscle breakdown, as assessed by plasma and muscle levels of 3MH, increased during the acute stage of Eimeria infection in turkey poults.

SUMMARY. The effects of prior (immunity) or concurrent administration of Eimeria acervulina or Eimeria tenella on cellular invasion in vivo and in vitro and on growth performance in white leghorn chickens (WLC) were examined. Weight gains of WLC immunized with E. acervulina and challenged with E. tenella were significantly greater than those of nonimmunized chicks challenged with E. tenella (this occurred despite the increased invasion by E. tenella in E. acervulina-immunized chicks that was reported earlier). The weight gains and modest but consistent improvements in intestinal lesion scores, feed conversion ratios, and oocyst shedding in immunized/challenged WLC indicated that E. acervulina conferred a small measure of protection against E tenella infection that was independent of the effect on invasion. In contrast, immunization of WLC with E. tenella significantly decreased (41?/o51%) invasion by E. acervulina as compared with that in nonimmunized WLC but had little effect on chick growth performance. Concurrent inoculation of chicks with E. tenella and E. acervulina had little effect on invasion by E. tenella sporozoites or on subsequent performance of the chicks. In vitro, prior exposure of cultured cells to either of two isolates of E. tenella also caused a significant decrease in invasion by E. acervulina. No gross changes occurred in the culture morphology between the E. tenella-inoculated and noninoculated cultures. Collectively, the data indicate that prior exposure of WLC and cultured cells to single isolates of avian coccidia markedly influenced invasion by other species but had less effect on the growth performance of the birds.

The effect of betaine and salinomycin on absorption of methionine and glucose in tissue from the duodenal loops of Eimeria acervulina-infected chicks was determined. Differences in the ultrastructure of the intestinal cells and parasite developmental stages were also examined. With a drug-resistant isolate of E. acervulina, methionine absorption was significantly higher in chicks fed a basal diet supplemented with 0.15% betaine as compared with absorption in chicks fed the unsupplemented basal diet. Addition of 66 ppm salinomycin to the diet containing betaine did not further enhance absorption. Conversely, with a drug-sensitive isolate, methionine absorption was significantly higher in chicks fed a diet supplemented with both betaine and salinomycin than in chicks fed the unsupplemented basal diet. Tissue from chicks fed any of the supplemented diets was usually significantly heavier than that from chicks fed the unsupplemented diet, even when weight gains of the birds were similar. Glucose absorption was similar in all diet groups. Epithelial cells in coccidia-infected and uninfected chicks fed diets supplemented with betaine or betaine plus salinomycin were less electron dense than cells from chicks fed diets that were not supplemented with betaine. Merozoites of E. acervulina in chicks fed diets supplemented with salinomycin had extensive membrane disruption and vacuolization, but the damage was prevented when betaine was added to the diet. Numerous merozoites and intact schizonts were seen in the intestinal lumen of chicks fed the diet containing betaine plus salinomycin.

SUMMARY. The effect of prior or simultaneous administration of Eimeria acervulina on cellular invasion by E. acervulina, E. tenella, or E. adenoeides was examined in vivo and/or in vitro. In chickens immunized with E. acervulina oocysts, invasion by sporozoites from a challenge inoculum of E. acervulina increased slightly over invasion in naive controls, and invasion by sporozoites of E. tenella and E. adenoeides increased by factors of 1.99 and 2.26, respectively, over that in controls. Conversely, simultaneous inoculation of E. acervulina along with E. tenella or E. adenoeides did not have a significant effect on invasion. Cultured baby hamster kidney cells that had been previously inoculated with E. acervulina sporozoites also supported significantly greater (by factors of 1.39 to 2.66) invasion by E. adenoeides sporozoites than did control cultures. The enhancement of invasion in vitro appeared to depend upon either the interval between the inoculation of cells with E. acervulina and E. adenoeides or the interval between the replating of the cells and their inoculation with E. adenoeides. There were no gross changes in the culture morphology between the E. acervulina-inoculated and noninoculated cultures. The data indicate that prior exposure to E. acervulina enhances invasion by other species of avian coccidia and, therefore, may exacerbate the infection produced by these species.

adenoeides in chickens; by 24 hr postinoculation (PI), the numbers of E. tenella and E. adenoeides sporozoites in the ceca had decreased markedly as compared with the numbers that initially invaded, and they did not differ significantly from each other. At 24 hr PI, however, transfer of cecal scrapings from chickens or turkeys inoculated with E. adenoeides produced infection in 53% of the recipient turkeys, but transfer of scrapings from either chickens or turkeys inoculated with E. tenella failed to produce infection in 20 attempts with recipient chickens. Cultured chicken peripheral blood monocytes (PBMs) that were inoculated with E. adenoeidessporozoites contained numerous vesicles that were recognized by the refractile body-specific monoclonal antibody 1209; the number of vesicles was markedly decreased in PBM cultures inoculated with gamma-irradiated E. adenoeides sporozoites. Very few vesicles were detected in the cytoplasm of turkey PBMs that contained E. tenella sporozoites, and none were detected in turkey PBMs containing E. adenoeides sporozoites. The survival of infective sporozoites, along with the secretion of refractile body antigen, may be more critical to the development of cross-species immunity than the number of sporozoites that initially invade the foreign host.

SUMMARY. Unimmunized chickens, given intraperitoneal injections of Sephadex at the same time that they were inoculated with oocysts of either Eimeria tenella or E. acervulina, had significantly lower lesion scores at 6 days postinoculation (PI) than unimmunized chickens that were injected with saline instead of Sephadex. Despite the difference in lesion scores, there was little effect on weight gain, except in one experiment, in which Sephadex-injected chickens gained significantly more weight than saline-injected chickens. In contrast, in chickens that were immunized by prolonged exposure to sporozoites of E. adenoeides, injection of Sephadex at the time of challenge with E. tenella did not reduce lesion scores or parasite development as compared with the uninjected chickens, and the weight gain of the Sephadexinjected challenged chickens fell to a level significantly lower than that of their saline-injected challenged counterparts. The data indicate that Sephadex injected at the time of oocyst inoculation 1) produces markedly different effects on lesion scores and weight gain in unimmunized and immunized chickens and 2) abrogates sporozoite-elicited immunity against

Repeated inoculation (immunization) of white leghorn chickens with oocysts of the turkey coccidium, Eimeria adenoeides, resulted in significantly improved weight gain and feed-conversion ratios (feed efficiency) after E. tenella challenge. However, the development E. tenella in the immunized chickens did not differ markedly from that in unimmunized chickens, and intestinal lesions remained severe (greater than 3.0). Apparently improved weight gain and feed efficiency can be maintained in the presence of extensive parasite development. The ability to elicit cross-protective immunity was abrogated when the E. adenoeides oocysts were exposed to 15 kRad of gamma irradiation before inoculation into the chickens. Sporozoites existing from irradiated oocysts of E. acervulina also failed to immunize the chickens against challenge with E. tenella but protected chickens almost completely against homologous challenge with E. acervulina. The results indicate that cross-species immunity is not elicited by all developmentally arrested sporozoites and that the ability to produce cross-species immunity can be destroyed by gamma irradiation of the immunizing species.

Eimeria maxima oocysts were exposed to various doses of gamma radiation that did not affect sporozoite invasion of intestinal epithelium but did prevent subsequent merogonic development therein. Although merogony and oocyst formation were inhibited, parasites exposed to 12 kRad radiation induced a level of immunity against E. maxima challenge equivalent to that induced by non-irradiated oocysts. Chickens immunized per os with 20 kRad-treated E. maxima oocysts were not protected against coccidial challenge. Immunization of chickens with a single low dose (five oocysts) of non-irradiated (0 kRad) or irradiated (12 kRad) E. maxima was effective in preventing weight depression after coccidial challenge. Immunofluorescence staining of intestinal tissue from chickens infected with irradiated (12 or 20 kRad) or non-irradiated (0 kRad) E. maxima oocysts with developmental stage-specific monoclonal antibodies showed that sporozoite invasion was similar in all groups. However, merogonic development was not observed at any time postinfection in chickens infected with irradiated oocysts, unlike the case with chickens infected with non-irradiated parasites. These results suggest that sporozoite-infected host cells are capable of eliciting complete protection against E. maxima challenge.

Repeated inoculation (immunization) of 2-week-old white leghorn chickens with 10(6) oocysts of the turkey coccidia Eimeria adenoeides or E. meleagrimitis partially protected chickens against moderate challenge with E. tenella or E. acervulina oocysts, but not with E. necatrix oocysts. After challenge, mean weight gains of the immunized chickens and the unchallenged controls did not differ significantly, but weight gains of unimmunized chickens were significantly lower. The mean feed-conversion ratio of the immunized challenged chickens was 3.14, as compared with 4.42 for unimmunized challenged control chickens. In general, immunization did not markedly reduce intestinal lesions. Repeated inoculation of chickens with the turkey coccidium E. gallopavonis failed to produce statistically significant protection against challenge with E. tenella, E. acervulina, or E. necatrix, as determined by weight gain, feed-conversion efficiency, and lesion scores. Antibody profiles of individual chickens did not correlate with protection.

SUMMARY. Four species of avian Eimeria invaded the intestine of foreign host birds in the same areas in which they invaded the natural host. Repeated inoculation (immunization) of chickens with the turkey coccidian, Eimeria adenoeides, partially protected the chickens against a subsequent challenge with 5.8 x 104 E. tenella oocysts. At 6 days post-challenge, the weight gain and feed conversion efficiency of the immunized chickens was significantly better than those of the chickens that were not immunized with E. adenoeides. Lesion scores and cellular invasion by the sporozoites were significantly lower in the immunized birds than in the unimmunized group. Electrophoresis and Western blot analysis identified changes in the serum antibody profiles of the chickens that appeared to be associated with the immunization and challenge programs. An antibody or antibodies recognizing a 60,000-molecularweight antigen of E. tenella sporozoites disappeared when chickens immunized with E. adenoeides were challenged with E. tenella; an antibody or antibodies recognizing a 23,000molecular-weight sporozoite antigen appeared within 6 days of challenge. Reciprocal studies, in which turkeys were immunized with E. tenella and challenged with E. adenoeides, showed little evidence of protection.

Prophylactic levels of three ionophorous antibiotics, monensin, salinomycin, and lasalocid, were administered to groups of chickens and turkeys. All three ionophores markedly inhibited invasion of cecal tissues by sporozoites of ionophore-sensitive (IS) Eimeria tenella. Monensin and salinomycin also reduced invasion in turkeys by sporozoites of E. adenoeides, but lasalocid only minimally inhibited invasion. Invasion of ceca of monensin-medicated chickens was significantly greater by sporozoites of ionophore-resistant (IR) E. tenella than of the IS isolate. Concomitant experiments showed significant differences in [14 C]monensin accumulation among IS and IR isolates of E. tenella. The decreased uptake of monensin by the IR isolates appeared to be accompanied by a decrease in responsiveness to the activity of monensin as well as to two other ionophores, salinomycin and narasin in cell culture. The amount of monensin, salinomycin or narasin required to inhibit development of E. tenella by 50% was 20 to 40 times higher for the IR isolates than for the IS ones. Collectively, the data suggest that differences in ionophore accumulation by IS and IR isolates of E. tenella might reflect differences in membrane chemistry and that these differences are responsible for the expressions of resistance that were observed in these studies. This expression of resistance appears to be common to all ionophores tested.

Two-week-old Diamond White poults were deprived of food, water, or food and water (food/water) for up to 3 days to estimate the effects of anorexia similar to that observed in parasitic infections. The weight loss of poults deprived of water for 48 hr was approximately the same as those deprived of feed. Loss of heart and pancreas weight was proportional to the loss of body weight, but moisture levels in the hearts of feed-deprived poults increased significantly by 24 hr. In contrast, moisture levels in the pancreas of poults in all three deprived groups decreased significantly by 24 hr; the pancreases were blanched and granular after 48 hr of feed deprivation. Packed red blood cell volumes increased significantly by 48 hr in water- and feed/water-deprived poults and by 72 hr in the feed-deprived group. Plasma carotenoid and plasma aspartate aminotransferase (GOT) levels of deprived birds did not differ significantly from controls. Plasma total proteins were significantly decreased in feed-deprived poults by 72 hr, significantly increased in water-deprived poults, and unchanged in poults deprived of both feed and water. Although sometimes significant, changes other than weight loss in the poults deprived of feed and/or water were not marked; therefore, even the severe anorexia sometimes associated with parasitic infections in turkeys probably would not appreciably effect the measurements of these parameters.

Exposure pf primary turkey kidney cell cultures to 100 μ g/ml wheat germ agglutinin (WGA), a lectin that binds N-acetylglucosamine (NAcGl), significantly inhibited invasion of the cells by Eimeria meleagrimitis sporozoites. However, neither succinyl-WGA, a lectin that retains an affinity for NAcGl but does not bind sialic acid, nor pokeweed mitogen, another lectin that binds NAcGl, similarly inhibited invasion. Collectively, the data suggested that the inhibition of invasion may be caused primarily by binding of WGA to anionic moieties on the host cell surface and not to specific binding to NAcGl. Exposure of cells to concanavalin A, phytohemagglutinin, or Ricinus communis lectin, as well as with pokeweed mitogen, failed to inhibit invasion by the sporozoites. Ultraviolet microscopy, using fluorescein-conjugated lectins, showed that the lectins had bound to the surface of the cultured cells. No binding of NAcGl or lectins to the surfaces of the sporozoites was demonstrated by either the clumping of the parasites in different lectin concentrations or the use of fluorescein-conjugated lectins. However, exposure of E. meleagrimitis sporozoites to NAcGl increased invasion of untreated cells by 50%.

In order to demonstrate the population dynamics of the northern fowl mite (NFM), Ornithonyssus sylviarum (Canestrini and Fanzago), and to characterize the chicken’s immune response to the mites, White Leghorn hens were infested with mites. Visual estimates revealed populations peaked on Wk 5, 4, and 3 after being infested with 10, 50, or about 2,000 mites, respectively. Individual feathers pulled from the vent area of hens 4 wk (28 days) after the hens were infested with either 10 or 50 mites had means of 7,513 and 7,009 mites, respectively. Estimated mean total populations of NFM on these same hens were 182,000 and 258,000, respectively. In two replications, actual counts of viable NFM following infestation with 50 mites increased ca. 10-fold by the 2nd wk after infestations were established in the feathers and then another two-fold during the 3rd wk. Populations in the 4th wk were about one-third of levels observed during the 3rd wk and continued to decline rapidly. Western blot analyses demonstrated the appearance of a mite-specific antibody in sera of White Leghorn hens that was approximately proportional in time of appearance and intensity to estimated NFM populations. Detection of mite-specific antibodies in the hens’ sera continued through 12 wk of the study even though mite populations declined after 3 to 6 wk. The rapid increase and then decline of NFM following infestation in previously uninfested chickens and the fact that the immune response persisted strongly suggests that the population decline was due to an immune response. Therefore control of the mite population by a vaccine may be possible.

The species-specificity and crossreactivity of serum antibodies (Ab) from birds immunized specifically with six different species of coccidia and of 24 hybridoma antibodies (Ab) developed against four species of chicken and two species of turkey coccidia were determined by use of the indirect immunofluorescent antibody (IFA) test on air-dried sporozoites. With few exceptions, the immune chicken sera were found to crossreact with all species of coccidia tested. Seven of the hybridoma Ab were species-specific, while the other 17 Ab demonstrated varying degrees of crossreactivity. Similar types of IFA patterns were seen with both the species-specific and crossreactive hybridoma Ab. Some of the crossreactive hybridoma Ab produced one type of IFA pattern with the sporozoites against which they were originally raised and different patterns with other species of sporozoites. The development of the hybridoma Ab has made it possible to identify the species of coccidia found in mixed infections and check the purity of laboratory strains.

A fusion protein of β-galactosidase and Eimeria tenella produced in a recombinant Escherichia coli strain was injected into chickens and elicited partial protection against an oral challenge with Eim. tenella parasites. The fusion protein contained a 31 kilodalton (kD) coccidial antigen designated as 5401. The DNA sequencing of the 5401 antigen-coding sequence revealed that this protein segment was highly negatively charged and strongly hydrophilic, and contained an amino-acid sequence repeated five times. A dose-titration study showed that immunizing chickens with a single subcutaneous injection of the 5401 antigen at 1,200 to 4,800 nanograms (ng)/bird in Freund's complete adjuvant decreased lesion scores, mortality, and feed conversions compared to unimmunized, challenged controls. Using the 1,200 and 2,400 ng/bird of the 5401 antigen, group weight gains were higher than for the unimmunized, challenged birds. In three other trials using the 5401 antigen at 2,400 ng/bird with light, medium, and heavy coccidial infections, significant protection was evidenced by reduced lesion scores, increased individual weight gains, or both. In addition, feed conversions were reduced when compared with unimmunized controls or birds immunized with a noncoccidial protein E. coli extract. Western blot analysis of sporozoite preparations with serum from 5401-immunized birds labeled two antigenic bands of 66 and less than 200 kD. These results indicate that the coccidial proteins produced in E. coli are potentially effective immunogens for protecting chickens against avian coccidiosis.

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.

SUMMARYEimeria meleagrimitis oocysts were stored at 4, 22, 32 or 41·5 °C for up to 1 year. Decreases in amylopectin levels (measured as glucose) and viability (measured as oocyst production and mortality in turkeys) of the oocysts were generally related to the length of time in storage and the storage temperature. Oocysts assayed immediately after harvest contained 58·29 ± 0·75 μg of glucose/106 oocysts. When the oocysts were stored at 4 °C for 162 days, the amylopectin level decreased to 65% of the original level. In oocysts stored at 22, 32 and 41·5 °C, amylopectin declined to approximately 20% within 162, 76, and 41 days, respectively. Oocysts stored at 4 °C for 1 year produced more oocysts in turkeys than the original fresh isolate, but caused no mortality. Oocyst production from oocysts stored at 22 and 32°C decreased gradually until, after 9 and 7 months respectively, no patent infections were produced. Oocyst production from oocysts stored at 41·5 °C was markedly reduced within 1 month and was not detected after 4 months.

SUMMARY Changes in levels of plasma xanthophyll, plasma retinol, liver retinol, and liver retinylpalmitate in poults infected with Eimeria meleagrimitis or E. adenoeides were measured by high-performance liquid chromatography. Infection with either species significantly reduced total plasma carotenoids; the reduction was due largely to a decrease in xanthophyll to approximately 50% of control levels on the day of maximum effect. In addition, E. meleagrimitis infection decreased plasma retinol levels from 1.84 ,g/ml plasma (controls) to 1.00 ,ug/ml plasma on day 6 postinoculation. Concomitantly, liver retinol levels fell from 0.23 ,ig/mg protein (controls) to 0.15 jg/mg protein, and liver retinylpalmitate levels fell from 0.74 /ug/mg protein (controls) to 0.44 jg/mg protein. In contrast, Eimeria adenoeides infection caused little change in either plasma or liver retinol levels.

The invasion of the intestinal epithelium of immunized and unimmunized turkeys and chickens by four species of Eimeria was quantitated. In unimmunized birds, E. adenoeides, E. acervulina, and E. tenella invaded primarily the areas in which first-generation schizonts subsequently developed. Eimeria meleagrimitis invaded a larger area of the intestine. Between 1 and 4 hr postinoculation, the numbers of intracellular sporozoites increased, but their location within the intestine was little changed. When birds were immunized with either of two lower intestinal species, E. adenoeides or E. tenella, and then challenged with the immunizing species, invasion was reduced by 36% to 55%. In contrast, immunizing and then challenging birds with either of two upper intestinal species, E. meleagrimitis or E. acervulina, did not reduce invasion: there were 44% more intracellular sporozoites in E. meleagrimitis-immunized turkeys and 11% more in E. acervulina-immunized chickens than in their unimmunized counterparts.

White leghorn hens were experimentally infested with northern fowl mites (Ornithonyssus sylviarum) and antibody responses to mite immunogens were monitored over 12 weeks. Mite burdens increased during the early phase of infestation and declined over the latter weeks of the study. Antigen was prepared from homogenized whole mites, which were then sonicated and extracted with non-ionic detergent. Antigen extract was fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and antibody-reactive polypeptides were identified by immunoblotting. At the start of infestation, hens had natural, pre-existing antibodies that reacted with several mite-extract components. Individual hens had different natural antibody reactivities; however, all birds had immunoglobulins reactive with extract polypeptides of 117,000, 77,000 and 36,000 molecular weight. A variety of mite extract components reacted with hen antibodies generated in response to experimental infestation. The number of antibody-reactive mite polypeptides increased through week 8 of infestation and then decreased by week 12. Fifteen polypeptides of northern fowl mite extract were reactive with antibodies developed by the majority of infested birds. These commonly reactive polypeptides had molecular weights ranging from 40,000 to 160,000. Glycoconjugates of fractionated mite extract were identified by blotting with lectins that have different carbohydrate binding specificities. Also identified were lectins that bound extract components with the same molecular weights as those moieties complexed by immunoglobulins of infested birds.

SUMMARY Earthworms were found to retain eggs and larvae of Ascaridia galli very briefly, and transmission can be attributed only to such eggs or larvae in transit in the digestive tract. Larvae of A. galli do not accumulate as do the larvae of Heterakis gallinarum, for the larvae of A. galli are voided within 48 hr of ingestion of the eggs. Since these larvae are unprotected, they must usually die, having little opportunity to gain access to a definitive host.

SUMMARY The osmotic fragility of red blood cells (RBC) from Eimeria adenoeides-infected turkey poults was cor ipared with that of RBC from control and water-deprived poults. At different hypotonic NaCI concentrations, lysis of RBC from infected poults was 10 to 35% less on day 4 postinoculation (PI) and 50 to 65% less on day 7 PI than that of controls. Red blood cells of poults deprived of water for 3 days were also resistant to lysis; the percent lysis was roughly the same as that of RBC from infected poults at day 7 PI. Incubating control RBC in plasma from infected poults, in extracts of infected' ceca, or at different pH levels did not increase their resistance to lysis, suggesting that neither a stabilizing factor in the plasma that had rapid effect on the RBC nor a transient shift in blood pH was involved. Mean RBC size differed little among infected, water-deprived, and control poults (14.0-14.2 X 8.0-8.1 x 3.8 im). However, although 3.5% of RBC population of control and water-deprived poults were immature (mid to late polychromatic erythrocytes), only 0.4% of the RBC of infected poults were immature. The data suggest that reduced water intake as well as other factors may be involved in the decreased osmotic fragility of RBC from poults infected with E. adenoeides. RESUMEN

Beltsville small white and Nicholas turkey poults, 1, 7, and 14 days old, were inoculated with mixed cultures of Eimeria adenoeides and E. meleagrimitis. Weight gain and feed conversion of 1-day-old poults were affected as severely as those of the older poults, and mortality was heaviest in this group, ranging from 25 to 45%. One dose of oocysts (2 x 10(4)-1.5 x 10(5], given at 1, 7, or 14 days of age, protected even the 1-day-old poults against challenge with 3 x 10(5) oocysts. Protection was comparable to that afforded by multiple immunizing doses given over 3 weeks. After challenge, little weight reduction or mortality was observed in immunized poults. Average feed conversions of the immunized challenged poults were 1.52 to 1.69 as compared with 2.98 to 5.14 for unimmunized challenged poults.