Four major types of surface conformation were observed in the ceca of uninoculated control chickens. Spatulate villi were found in the cecal neck region, low ridges in the region where the neck expands, protruding collarlike structures in the mid cecal pouch, and flattened collars in the distal portion. In ceca infected with Eimeria tenella, there was some erosion and sloughing of the mucosal cells. These lesions were slight in the neck region, more severe in the dilated portion, most severe in the midregion, and moderate in the distal area. Oocysts were observed in the mucosal tissue of the cecal pouch.

Animals↗

PubMedDate not supplied

Interaction of aflatoxin with Eimeria tenella infection and monensin in young broiler chickens.

Young broiler chicks inoculated with Eimeria tenella and given a diet containing 2.5 mug aflatoxin/g had significantly higher mortality than birds with aflatoxicosis or coccidiosis alone or uninoculated controls. This effect was seen even when a light coccidial infection alone did not increase mortality or cause weight depression. In addition this higher mortality with the combination began earleir and occurred at a higher rate than did mortality from aflatoxin or cecal coccidiosis alone. Dietary monensin sodium (99 umg/g) did not completely prevent mortality and weight depression when aflatoxin and E. tenella were in combination. Aflatoxin and E. tenella singly significantly depressed three-week body weights; however, the depression was most severe when the two were in combination. Both dietary aflatoxin and E. tenella significantly reduced hemoglobin, packed cell volume, and plasma pigmentation, and in combination resulted in more severely reduced hemoglobin, packed cell volume, and plasma pigmentation. Coccidial lesion scores were significantly less for the combination of E. tenella and aflatoxicosis than for coccidiosis alone. This atypical response of the ceca to E. tenella in the presence of dietary aflatoxin was characterized by less distended ceca, very little coagulated blood in the ceca, and apparently more profuse cecal hemorrhage.

Aflatoxins↗

PubMedDate not supplied

Characterization of the toxicity of the mycotoxins aflatoxin, ochratoxin, and T-2 toxin in game birds. II. Ringneck pheasant.

Ringneck pheasants were fed diets containing 1.25, 2.5, or 5 ppm aflatoxin; 1, 2, or 4 ppm ochratoxin A (OA); or 4, 8, or 16 ppm T-2 toxin. Severe toxin-induced mortality was seen during the first to third weeks with 2.50 and 5.00 ppm aflatoxin (92.5% and 97.5%, respectively), compared with the mortality in control pheasants fed no toxin (0%). Slight mortality (less than or equal to 5%) was seen with OA and T-2 toxin. Body weights were significantly decreased by the lowest level (1.25 ppm) of aflatoxin by 2 weeks of age, by the two highest levels of aflatoxin by 1 week of age, and by 16 ppm T-2 toxin by 1 week of age. The feed-conversion ratio was increased by 2.50 and 5.00 ppm aflatoxin compared with the feed-conversion ratio in controls, although high mortality may have influenced the results. Aflatoxin had no effect on liver weight, but OA increased kidney weight in 3-week-old pheasants. Mouth lesions were seen in some of the pheasants fed T-2 toxin.

Aflatoxins↗

PubMedDate not supplied

Characterization of the toxicity of the mycotoxins aflatoxin, ochratoxin, and T-2 toxin in game birds. III. Bobwhite and Japanese quail.

Bobwhite and Japanese quail were fed diets containing 1.25, 2.50, or 5.00 ppm aflatoxin; 1, 2, or 4 ppm ochratoxin A (OA); or 4, 8, or 16 ppm T-2 toxin. Aflatoxin induced mortality in bobwhites during the second and third week with 1.25 ppm (10%), 2.50 ppm (30%), and 5.00 ppm (40%), and during the same period with T-2 toxin at 8 ppm (20%) and 16 ppm (22.5%). Body weights of bobwhite quail were significantly decreased by the two higher levels of aflatoxin by 2 weeks of age, and by the two higher levels of T-2 toxin by 1 week of age. In Japanese quail, only the highest level of aflatoxin and T-2 toxin reduced body weight (by 3 weeks and by 1 week of age, respectively), and even then to a much lesser extent than in bobwhites (less than 10%). Aflatoxin did not affect feed-conversion ratio (FCR) in bobwhite quail, but the two higher levels of T-2 toxin increased FCR. None of the toxins induced mortality or increased the FCR in Japanese quail. Aflatoxin increased liver weight in both bobwhite and Japanese quail. OA increased kidney weight in 3-week-old Japanese quail but had no effect on the kidney weight of bobwhite quail. Mouth lesions were progressively more severe in bobwhite quail fed increasing levels of T-2 toxin, but lesions were far less severe in Japanese quail.

Aflatoxins↗

PubMedDate not supplied

Characterization of the toxicity of the mycotoxins aflatoxin, ochratoxin, and T-2 toxin in game birds. I. Chukar partridge.

Chukar partridges were fed diets containing 1.25, 2.5, or 5 ppm aflatoxin; 1, 2, or 4 ppm ochratoxin A (OA); or 4, 8, or 16 ppm T-2 toxin. Toxin-induced mortality was seen during the third week with 4 ppm OA (12.5%) and 16 ppm T-2 toxin (15%), compared with the mortality in control chukars fed no toxin (2.5%). Body weights were significantly decreased by the highest level of aflatoxin at 3 weeks of age, by the highest level of OA by 2 weeks of age, and by 8 and 16 ppm T-2 toxin by 1 week of age. Aflatoxin did not affect liver weight and OA did not increase kidney weight in 3-week-old chukars. There was a slight decrease in kidney weight in chukars fed 4 ppm OA; however, the decrease was related to the decrease in body weight produced by the toxin. Mouth lesions were seen at all levels of T-2 toxin fed.

Aflatoxins↗

PubMedDate not supplied

Coccidiosis and intestinal pH in chickens.

The intestinal contents of white Leghorn cockerels were significantly lower in pH in birds infected with Eimeria mivati, E. maxima, or E. necatrix than in uninoculated control birds. The particular Eimeria species used affected the region of the intestine involved, the days (5-9 postinoculation) on which pH decreased, and the magnitude of the decrease. The effects on the magnitude and frequency of pH decrease were as follows: E. mivati, marked in the duodenum and jejunum, variable in the ileum; E. maxima, slight in the duodenum, variable in the jejunum and ileum; E. necatrix, no change in the duodenum, variable in the jejunum and ileum. Infection with E. tenella did not change the intestinal pH. The pH of the gizzard was occasionally higher in birds infected with E. mivati or E. necatrix than in uninoculated control birds. With all four species, on some days the pH in the ceca was higher than in the ceca of controls. These results and previous reports indicate that infection with one of the above four species or with E. acervulina or E. brunetti produces the greatest and most consistent decrease in pH in the region of the intestine where the particular species characteristically produces the severest infection.

Animals↗

PubMedDate not supplied

In vitro and in vivo characterization of avian reoviruses. II. Clinical evaluation of chickens infected with two avian reovirus pathotypes.

The effect of two avian reovirus isolates (2408 and 1733) on digestion and nutrient metabolism in infected chickens was assessed by an in vitro absorption assay and clinical blood chemistry analysis. Birds of various ages were inoculated orally and intratracheally with reovirus and sampled periodically for the respective assays. Transitory malabsorption was observed in the duodenum of birds infected with reovirus 2408. Conversely, increased absorption was detected in the ileum of these same birds. Clinical blood chemistry analyses of birds infected with both isolates revealed that severely affected birds had abnormally elevated plasma total protein, plasma albumin, and calcium levels. Decreases were found in percent bone ash and, due to abnormally high globulin levels, in albumin:globulin (A:G) ratios. A significant (P less than 0.05) correlation between body weights and total protein, albumin, A:G ratio, and bone ash was found in infected birds. The most pronounced metabolic and physiologic changes occurred in the severely affected birds, and, in general, pathogenicity of the isolates was reflected by the degree of metabolic change.

Animals↗

PubMedDate not supplied

Concurrent infections with reoviruses and coccidia in broilers.

These experiments investigated the interaction among two species of coccidia (Eimeria acervulina and E. mitis) and three strains of reovirus (virus 2035, a weak to moderate pathogen; and viruses 2408 and 1733, severe pathogens). When reoviruses were not present, high inoculation dosages (10(6) sporulated oocysts/bird) of both E. acervulina and E. mitis depressed weight gain, plasma pigment, and plasma protein. Low doses of coccidia (10(4) oocysts) in the absence of virus had no such effect on weight gain. When high doses of coccidia were present at the same time as virus 2035 or 2408, they resulted in a significantly greater depression of weight gain than when either virus or coccidia were present alone. With virus 2035, this greater depression was seen even when low doses of coccidia were used. Lesion scores due to coccidiosis and the number of oocysts produced were not affected by previous exposure to reovirus. Both coccidiosis and reovirus infections increased the frequency of some leg problems and other abnormal conditions. The most obvious interaction between coccidia and reovirus was the marked increase in swollen hocks seen when coccidia and virus 2035 were present together (20-27%) compared with either the virus or coccidia alone (0-10%). Virus 2408 interfered slightly with the development of immunity to coccidia. There was some indication that early coccidiosis could increase the ability of some virus isolates to infect various tissues of the host.

Animals↗

PubMedDate not supplied

Interaction of low-pathogenicity reoviruses and low levels of infection with several coccidial species.

Various combinations of reoviruses and coccidia were studied to see if interactions would occur. Two reoviruses were used: virus 2035, a moderate to low pathogen, and virus 2177, a nonpathogen. Coccidia used were Eimeria acervulina, E. mitis, and E. maxima at dosages of 10(3) or 10(4) sporulated oocysts/chick and E. brunetti at 10(4) sporulated oocysts/chick. In Hubbard-Hubbard cockerels, a combination of virus 2035 and E. acervulina (10(4) oocysts/chick) or E. maxima (10(3) oocysts/chick) significantly (P less than or equal to 0.05) increased the frequency of stunting (% of chicks with body weight less than 80% of controls) and further depressed weight gain over that seen with either virus or coccidia alone. Conversely, virus 2177 ameliorated the same effects in Shaver-Arbor Acre cockerels given 10(4) oocysts/chick of E. mitis or E. maxima. The interaction could not be attributed to changes in the degree of coccidial infection based on oocyst production. Reovirus did not generally change the effect of coccidia on levels of plasma pigment and plasma protein. In Hubbard-Hubbard cockerels, coccidia-induced effects were not ameliorated by virus 2177, suggesting that breed difference in interaction can be expected.

Animals↗

PubMedDate not supplied

Effect of coccidiosis on reproductive maturation of male Japanese quail.

The effects of coccidiosis on reproductive development of male Japanese quail were examined. Male Japanese quail were exposed to high (5 x 10(5) sporulated oocysts/quail) or low (5 x 10(3) sporulated oocysts/quail) doses of Eimeria uzura at 16 or 30 days of age and sampled at 37 days. Quail given high doses of coccidia had reduced testes weight and lowered circulating concentrations of androgen compared with control males. Low doses of coccidia did not affect testes weight but did result in elevated plasma androgen levels. There were no differences in average testes weights by 51 days; however, plasma androgen was still reduced in most groups. To study the effects of coccidiosis on egg production, males exposed to high doses of coccidia at 16 (16H) or 30 (30H) days of age were mated with control females, and control males were mated with control or 16H females. The onset of laying was delayed for 5 days in the control male: 16H female group. During the first week of production, eggs from females bred to 30H males had lower fertility and hatchability than those bred to control or 16H males. By the third week of production, levels of fertility were similar. Apparently, exposure of quails to coccidiosis before sexual maturation might result in long-term effects on later reproductive capability.

Androgens↗

PubMedDate not supplied

Comparison of disease susceptibility and subclass-specific antibody response in SC and FP chickens experimentally inoculated with Eimeria tenella, E. acervulina, or E. maxima.

Susceptibility to disease and the subclass-specific antibody response to Eimeria tenella, E. acervulina, and E. maxima were compared in two inbred strains of chickens, FP (B15B21) and SC (B2B2). FP strain was more susceptible to coccidiosis than SC chickens based on oocyst production, lesion score, and clinical signs. FP chickens infected with E. tenella had more severe cecal lesions and a significantly lower hematocrit level than SC chickens. FP chickens infected with E. acervulina excreted five times as many oocysts at 6 days postinfection as SC and showed a 71% reduction in plasma carotenoid level compared with controls (56% reduction in SC chickens). Body-weight change did not correlate with other signs of disease. Both SC and FP chickens produced high levels of serum IgM and IgG and biliary IgA. Although SC chickens had a slightly higher antibody response than FP chickens at 7 days postinoculation, both strains maintained high levels of IgM, IgG, and IgA for a prolonged period post primary inoculation. Although SC and FP chickens show different disease susceptibility to coccidiosis, they demonstrate similar antibody response.

Animals↗

PubMedDate not supplied

Cyclocoelum mutabile infection and aortic rupture in an American coot (Fulica americana).

An American coot (Fulica americana) was found dead within the enclosed research compound of the South Central Poultry Research Laboratory at Mississippi State, Mississippi. Gross and microscopic examinations revealed the bird to be in good body condition; however, blood from the beak cavity and external nares was present. Biliary congestion, hemopericardium, blood-filled air sacs, and a ruptured, ascending aorta were also noted. Nineteen trematodes (Cyclocoelum mutabile) were found within the body cavity at necropsy. Bacteriological examination revealed the presence of Escherichia coli in both the heart and liver and Pseudomonas putida in the liver only. No virus was isolated.

Animals↗