Interactive effects of turkeypox virus and Plasmodium hermani on Turkey poults

Two experiments were conducted to examine the interactive effects of two disease agents of wild turkeys (Meleagris gallopavo), turkeypox virus and the malarial organism, Plasmodium hermani, on the health of turkey poults. Groups of domestic broad-breasted white turkey poults of 1 and 10 wk of age were infected with either turkeypox virus, P. hermani, both turkeypox virus and P. hermani, or were maintained as uninfected controls. The strains of turkeypox virus and P. hermani had been isolated from wild turkeys in southern Florida (USA). The goals of these experiments were two-fold and included both an examination of age differences in response to infections, and an examination of the effects of dual versus singular infections with the two agents. Both singular and concomitant infections of turkeypox virus and P. hermani were more detrimental to poults infected at 1 wk of age than to those infected at 10 wk, based on mortality, weight gain, and parasitemia. Dual infections of turkeypox virus and P. hermani were found to be slightly more harmful to 1-wk-old poults than were singular infections. No such interactive effects were noted in the poults infected at 10 wk of age.     

Characterization of glycogen in selected tissues of turkey poults with spontaneous round heart disease and furazolidone-induced cardiomyopathy.

Furazolidone (FZ) at 700 ppm was added to feed mixtures fed turkey poults 2--5 weeks after hatching to induce acute experimental cardiomyopathy. Poults in the control pen received the same ration but without FZ. From EKG data obtained at weekly intervals, poults were selected for sacrifice at 5 and 10 weeks of age. Poults were sacrificed by cervical dislocation and appropriate samples of tissue from the left ventricle, liver, pectoralis and tibialis cranialis muscles were removed for glycogen assays. Character of glycogen, as determined by percent of branching and number of glucose units per segment, was not significantly altered in poults with spontaneous round heart disease or FZ-induced cardiomyopathy. This suggests that the glycogen accumulation noted in these conditions most closely resembles type II glycogenosis.     

Prevalence of parasitism by Amblyomma americanum on wild turkey poults as influenced by prescribed burning.

Captive-raised eastern wild turkey (Meleagris gallopavo silvestris) poults were allowed to forage on either recently burned plots or on plots that had not been burned during the previous 3 years. Following a two hour exposure on the study plots, external parasites were recovered from all poults. The louse (Menacanthus stramineus) and the lone star tick (Amblyomma americanum) were the only parasites recovered. Fifty-nine poults exposed to the burned plots had a significantly (P less than 0.001) lower prevalence of A. americanum infestation than did 57 poults exposed to the unbured plots. Thirty-five percent of the poults exposed to the unburned plots were infested by A. americanum. A single A. americanum was recovered from one poult exposed to burned plots.     

Segregation of Two Alleles for Color of down in Parthenogenetic and Normal Turkey Embryos and Poults

Data were collected on the down color of 1,386 parthenogenetic embryos and poults from eggs of 306 young virgin and older nonmated bronze turkey hens. Each hen involved was heterozygous (Cc) for alleles which affect feather pigmentation. Six hundred and sixty nine white and 717 colored parthenogenetic embryos and poults were observed, a 1:1 ratio. Subsequently, 89 of these 306 heterozygous bronze hens were inseminated with semen from BSW (cc) males and down color of embryos and poults from fertilized eggs recorded. the 89 females produced a total of 233 white and 239 colored normal embryos and poults. The 1:1 ratio for down color among both parthenogenetic and normal embryos and poults shows that, in both instances, the two alleles at a locus on an autosome segregated equally. Four possible cytological routes which would lead to diploidy were discussed.     

Effect of turkey (Meleagridis gallopavo) breeder hen age and egg size on poult development. 2. Intestinal villus growth, enterocyte migration and proliferation of the turkey poult

Villus growth, enterocyte migration and proliferation were measured in the small intestine of poults (Meleagridis gallopavo) to determine if hen age and/or egg size influences these characteristics during the first week after hatching. At hatching, distal jejunal villi were 22.8 μm longer in poults from the older (48 weeks) versus the younger (34 weeks) hens (P<0.05). Similarly, labeled enterocytes in distal jejunal sections from poults from the older hens had migrated 28 μm (10%) farther along the crypt-villus axis at hatching, as compared to poults from the younger hens (P<0.05). Villus growth differences and enterocyte migration were not consistently affected by hen age or egg weight class in poults from 1 to 7 days old. These results suggest that even though intestinal villi may be more advanced developmentally at hatch in poults from the older hens, however post-hatch growth of the intestine or the poult is not affected by hen age or egg weight class.     

Myocardial calcium levels in furazolidone-induced cardiomyopathy in turkey poults

Myocardial calcium levels were measured in control turkey poults and in poults with furazolidone (FZ)-induced cardiomyopathy. FZ at a dose of 700 ppm added to the feed of poults from 2 to 5 weeks post-hatching produced the typical round-heart syndrome but had little effect on the calcium levels in the myocardium. Data suggest that the mechanism of FZ cardiotoxicity is not associated with calcium overload.     

Recent studies on aspergillosis in turkey poults

A review of the studies on aspergillosis in turkey poults at the National Animal Disease Center include limited field studies, pathogenicity studies, and vaccine development. Natural ventilation in turkey rearing houses was effective in reducing airborne propagules of four major fungal genera, but the effectiveness of ventilation appeared to be limited by the width of the building. Aspergillus fumigatus was more effective than A. flavus in producing mortalities in aerosol exposed poults. Toxigenicity of A. flavus did not enhance its pathogenicity, and no apparent aflatoxin production occurred during pathogenesis in infected turkey poults. Spores of A. fumigatus were disseminated quite rapidly in poults exposed to aerosols, and alveolar macrophages from respiratory lavages taken immediately after exposure contained spores of A. fumigatus. Vaccines produced from germlings of A. fumigatus and administered to turkey poults were the most efficacious of five vaccines tested against challenge exposure to aerosols of A. fumigatus spores.     

Molecular characterization of an avian astrovirus

Astroviruses are known to cause enteric disease in several animal species, including turkeys. However, only human astroviruses have been well characterized at the nucleotide level. Herein we report the nucleotide sequence, genomic organization, and predicted amino acid sequence of a turkey astrovirus isolated from poults with an emerging enteric disease.     

Evaluation of allopurinol as a cardioprotectant in ethanol-fed turkey poults

Cardioprotectant effects of allopurinol were investigated in ethanol-fed poults during induction of cardiomyopathy and during a period of ethanol abstinence. In young poults fed ethanol, allopurinol has an additive effect on depression of growth but has little or no effect on caloric consumption. Allopurinol significantly depresses heart weight and heart weight to body weight ratios in young poults. In poults 5 weeks and older, allopurinol depresses significantly body weight and caloric consumption. Although allopurinol depresses heart weight in older poults, it appears to have little or no effect on heart weight to body weight ratios. Cardioprotective effect of allopurinol is more apparent during the inductive process than during the recovery phase.     

Plasma uric acid levels in ethanol-fed turkey poults treated with allopurinol

Plasma uric acid levels were determined in ethanol-fed poults following administration of allopurinol. In young poults, allopurinol at a dose of 50 mg/kg significantly depressed plasma uric acid levels 6 hr post-dosing. At 11 hr post-dosing, plasma uric acid levels were significantly elevated in the allopurinol-treated poults when compared with control poults. During a period of ethanol abstinence, allopurinol at a dose of 40 mg/kg significantly depressed plasma uric acid levels up to 8 hr post-dosing. At a dose of 30 mg/kg, plasma uric acid levels were similar to control values at 4 and 6 hr post-dosing. Data suggest that plasma uric acid levels can be depressed in ethanol poults when allopurinol is administered every 8 hr at a dose of 40-50 mg/kg of body weight.     

Early post-hatch fasting induces satellite cell self-renewal

Early post-hatch satellite cell kinetics are an important aspect of muscle development, and understanding the interplay between fasting and muscle development will lead to improvements in muscle mass following an illness, and optimal meat production. The objective of this experiment was to test the influence of immediate post-hatch fasting on satellite cells in the poult. Male Nicholas poults (Meleagris gallopavo) were placed into two treatments: a fed treatment with immediate access to feed and water upon placement and a fasted treatment without access to feed and water for the first three days post-hatch. 5-bromo-2'-deoxyuridine (BrdU) was injected intra-abdominally in all poults to label mitotically active satellite cells. The pectoralis thoracicus muscle was harvested two hours following the BrdU injection. Immunohistochemistry for BrdU, Pax7, Bcl-2, Pax7 with BrdU, and determining myofiber cross-sectional area along with computer-based image analysis was used to study muscle development. Fed poults had higher body masses throughout the experiment (P< or =0.01), and they had higher pectoralis thoracicus muscle mass (P< or =0.01) at ten days of age than the fasted poults. Fed poults had higher satellite cell mitotic activity at three days and four days of age (P< or =0.01) compared to the fasted poults. However, Pax7 labeling index was higher in the fasted poults (P< or =0.01) at three days, four days, and five days post-hatch than the fed group. Similarly Bcl-2 labeling was higher in the fasted than in the fed group at three days post-hatch. Therefore, fasting depleted proliferating satellite cells indicated by the lower BrdU labeling in the fasted poults compared to the fed poults, and conserved the satellite cell proliferative reserve indicated by the higher level of Pax7 labeling for the fasted poults compared to the fed poults.     

Plasma prolactin levels in incubating turkey hens during pipping of the eggs and after introduction of poults into the nest

Plasma levels of prolactin (Prl) associated with incubation and maternal behavior were compared in turkey hens allowed to incubate 10 fertile eggs (Group I, n = 9) or 10 infertile eggs (Group II, n = 7) in open nest boxes. At the end of the day that the first egg hatched, all unhatched eggs were removed from Group I hens and each hen was given 10 poults. At the end of the following day, infertile eggs were removed from Group II hens and each hen was given 10 poults. Although pipping of the eggs changed the incubation behavior of Group I hens, it had no effect on plasma Prl. Subsequent hatch of the eggs and/or presence of poults resulted, within 24 h, in a sharp fall in Prl levels, abandonment of the nests, and a shift to maternal behavior. Visual and auditory exposure to Group I poults had no effect on plasma Prl or incubation behavior of Group II hens incubating infertile eggs in adjacent pens. However, within 24 h after the infertile eggs were exchanged for newly hatched poults, Prl levels in Group II hens declined sharply and the hens abandoned the nests and showed maternal behavior similar to that observed in Group I hens. No significant relationships were found in either group between plasma Prl levels and quality of incubation or maternal behavior.     

Effect of turkey (Meleagridis gallopavo) breeder hen age and egg size on poult development. 1. Intestinal growth and glucose tolerance of the turkey poult

Three experiments were conducted to determine if turkey (Meleagridis gallopavo) hen age and egg weight affect poult intestinal development and glucose tolerance during the first week after hatching. Differences in glucose tolerance were not consistent across the experiments. In experiment 1, 4-day-old poults from the younger hens and lightest egg weight class had significantly greater fasting plasma glucose concentrations (P<0.04) and were also higher at 30 and 60 min post-injection of 250 mg glucose. In experiment 2, egg weight class had no significant effects on plasma glucose concentrations of 4-day-old poults (after injection of 2.5 mg glucose/g body weight). In experiment 3, plasma glucose concentrations were not different between groups at 0 or 30 min post-injection (3.75 mg glucose/g body weight), however, poults from the younger hens had 79–90 mg/dl higher plasma glucose concentrations 60 min post-injection versus poults from the older hens. Neither egg weight class or hen age consistently affected small intestinal weight, length, or density (g/cm) measures across experiments.     

Effect of Bile on Infectivity of Histomonas meleagridis of Liver Origin

SYNOPSIS After 30 min exposure to fresh turkey bile at 99 F, 100,000 Histomonas meleagridis of turkey liver origin failed to infect any of 20 poults inoculated rectally. Only one of 20 poults similarly inoculated with histomonads exposed to fresh turkey bile for only 5 min at 99 F became infected. Fifteen of 20 poults became infected following rectal inoculation with 100,000 H. meleagridis of liver origin held in physiologic saline for 30 min at 99 F. All infected birds developed liver lesions and died. Altho H. meleagridis was very abundant in the livers of all potential donor poults and all infected recipient poults, histomonads were never found in the gall bladders of any of these birds. In some such birds, a few apparently degenerating histomonads were detected in the duodenum near the entrance of the bile ducts. Histomonads of liver origin are regarded as of little or no consequence in the transmission of this protozoon.     

Rye Affects Bacterial Translocation,Intestinal Viscosity,Microbiota Composition and Bone Mineralization in Turkey Poults

Previously, we have reported that rye significantly increased both viscosity and Clostridium perfringens proliferation when compared with corn in an in vitro digestive model. Two independent trials were conducted to evaluate the effect of rye as a source of energy on bacterial translocation, intestinal viscosity, gut microbiota composition, and bone mineralization, when compared with corn in turkey poults. In each experiment, day-of-hatch, turkey poults were randomly assigned to either a corn or a rye diet (n = 0 /group). At 10 d of age, in both experiments, 12 birds/group were given an oral gavage dose of fluorescein isothiocyanate dextran (FITC-d). After 2.5 h of oral gavage, blood and liver samples were collected to evaluate the passage of FITC-d and bacterial translocation (BT) respectively. Duodenum, ileum and cecum gut sections were collected to evaluate intestinal viscosity and to enumerate gut microbiota. Tibias were collected for observation of bone parameters. Broilers fed with a rye diet showed increased (p<0.05) intestinal viscosity, BT, and serum FITC-d. Bacterial enumeration revealed that turkey poults fed with rye had increased the number of total lactic acid bacteria (LAB) in all three sections of the gastrointestinal tract evaluated when compared to turkey poults fed with corn. Turkey poults fed with rye also had significantly higher coliforms in duodenum and ileum but not in the ceca, whereas the total number of anaerobes increased only in duodenum. A significant reduction in bone strength and bone mineralization was observed in turkey poults fed with rye when compared with corn fed turkey poults. In conclusion, rye evoked mucosal damage in turkey poults that increased intestinal viscosity, increased leakage through the intestinal tract, and altered the microbiota composition and bone mineralization. Studies to evaluate dietary inclusion of selected Direct-Fed Microbial (DFM) candidates that produce exogenous enzymes in rye fed turkey poults are currently being evaluated.     

Precocial sexual behaviour in turkeys (Meleagris gallopavo L.)

Precocial struts were observed in 95 per cent of turkey poults of both sexes, wild and domesticated. In male turkey poults it occurred with about constant frequency up to day 100 (domesticated turkey: 0·6 struts per hr of observation time; wild turkeys: 0·1 struts per hr observation time) and dramatically increased in frequency after day 130, In female turkey poults, the incidence was much lower (about 0·01 struts per hr observation time) and did not shown any marked increase later on. Struts can be elicited by objects the poults are imprinted upon (mother hen, siblings, or human hand or foot in human imprinted poults). However, precocial struts can also occur spontaneously; i.e. in the absence of external stimulation by an imprinting object.     

Effects of stressors on blood glucose and hepatic glycogen concentrations in turkey poults.

1. The putatively stressful procedures of sexing, toe trimming, snood removal, beak trimming and injection of antibiotic solution, as performed in a commercial hatchery, elevated blood glucose levels and depressed hepatic glycogen levels in newly-hatched turkey poults. 2. The first procedure performed, cloacal sexing, was sufficient to elevate blood glucose, but all procedures were required before depression of hepatic glycogen occurred. 3. Blood glucose levels declined in both untreated (INITIAL) and fully-treated (FINAL) poults over a 24 hr holding period. 4. Hepatic glycogen declined with 24 hr holding of INITIAL poults but increased with holding of FINAL poults.     

Infectivity of Histomonas meleagridis of Cecal and Liver Origins Compared

SYNOPSIS. Turkey poults were inoculated rectally with 100, 1000, 10,000, or 100,000 Histomonas meleagridis from the ceca of a group of experimentally infected turkeys. Other poults were given the same numbers of histomonads from an infected liver from the same group of source birds, Comparisons of the incidence of infection, liver involvement, mortality, and average survival time following these inoculations showed that organisms of cecal origin were about 100 times more effective in producing histomoniasis than were organisms of liver origin. It is suggested that this difference in infectivity resulted from heavy losses of histomonads of liver origin that were due to various selective processes.     

Production of gliotoxin during the pathogenic state in turkey poults byAspergillus fumigatus Fresenius

Turkey poults were given either of two different dosages of two different gliotoxin-producing strains ofAspergillus fumigatus. Infected lung tissue was examined postmortem for the presence of gliotoxin. Gliotoxin was found in lung tissue of ten poults infected with one strain and in seven of ten poults infected with the other strain. Concentrations of gliotoxin in the tissue exceeded 6 ppm in some of the infected tissues. The concentration of gliotoxin found in infected tissue did not appear to be correlated with the dosage of organism given. Considering the pathologic changes observed in turkey poults with aspergillosis and the production of gliotoxin during the pathogenic state in turkey poults, gliotoxin is considered likely to be involved in avian aspergillosis. Disclaimer: Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable.     

Eimeria meleagrimitis, E. adenoeides, and E. dispersa: Severity of infection and changes in the intestinal mucosa of the Turkey

Glucose and methionine were malabsorbed in some intestinal regions of turkeys infected with Eimeria meleagrimitis, E. adenoeides, or E. dispersa. The decrease in absorption was not always related to the numbers of parasites in the cells or the extent of damage to the mucosa. With E. adenoeides, malabsorption was found in the jejunum even though parasites were not present. Conversely, with E. dispersa, no malabsorption was observed in the duodenum even though light microscopy showed numerous parasites. In many intestinal regions, damage to the mucosal surface visible with scanning electron microscopy (SEM) was slight or absent, although malabsorption was marked. No changes were noted with SEM in the structure and orientation of the brush border in these regions. Villar height was significantly reduced in the regions of heaviest infection when intestinal damage was visible. Conversely, the crypts of Lieberkühn were often two or three times as deep in infected poults as in uninfected poults. In general, no differences were found in the thickness of the circular and longitudinal muscle layers between the infected and uninfected poults. The dry weight of the intestinal tissue was less from infected poults than from uninoculated controls and was related to both region of the intestine and severity of the infection.