Colonization of the intestine of turkey embryos exposed to Mycoplasma iowae

Eight-day-old turkey embryos were inoculated into the yolk sac with 3 X 10(5) colony-forming units of Mycoplasma iowae strain D112 in order to study the growth-depressing effect, the histopathological changes, and colonization of the intestinal tract. The embryo: egg weight ratio was significantly lower in the inoculated eggs than in controls. Histologically, there were infiltrations in parenchymatous organs and chorioallantoic membranes with heterophilic granulocytes. M. Iowae was demonstrated on the intestinal mucosa by antibody fluorescent microscopy and by transmission electron microscopy. Attaching mycoplasmas had a distinct morphology; the segment in contact with enterocytes was cone-shaped and had finely granulated cytoplasma which was abruptly separated from the distal coarsely granulated area. We conclude that M. iowae has a predilection for the intestinal tract of avian hosts.     

Efficacy trials in turkey poults with tylosin tartrate against Mycoplasma gallisepticum and Mycoplasma meleagridis.

Tylosin tartrate, administered in the drinking water at a concentration of 0.55 g/litre for the first three days after hatching, was highly effective in controlling the adverse consequences of a Mycoplasma gallisepticum infection, established by air sac injection at one day of age, in turkey poults. Tylosin was ineffective in controlling M meleagridis infections established in embryo or at one day of age when administered in the drinking water of poults. Both mycoplasma isolates used were inhibited in vitro by a tylosin concentration of 0.1 mug/ml.     

Rickets in turkey poults

Fifteen outbreaks of rickets were diagnosed in turkey poults in Saskatchewan between 1978 and 1981. No relationship to farm, source of poults, or source of feed was apparent. Most outbreaks started when the poults were between 10 and 14 days of age, and they had recovered by 28 days of age. Losses varied from 1% to 14% of poults started. Skeletal lesions were characteristic of a vitamin D or calcium deficiency. On the basis of chemical analyses, adequate levels of calcium and phosphorus and proper amounts of vitamin premixes were present in the feed, but in five outbreaks biological feed tests implicated feed as a causative factor. The severity of rickets in poults fed defective feeds was markedly reduced by providing the poults with extra vitamin D in the drinking water or by injection. Two premixes used in different feeds contained adequate available vitamin D on the basis of biological testing. In some of the outbreaks, the rickets may have resulted from inadequate distribution of vitamin D in the feed, destruction of vitamin D during feed processing, or some unknown factor in the feed interfering with vitamin D utilization.     

Culturing anomalies associated with Mycoplasma recovered from the tissues of chicks and turkey poults experimentally infected with Mycoplasma gallisepticum or Mycoplasma gallinarum.

Tissues of mycoplasma infected chicks and turkey poults were cultured and subcultured on mycoplasma agar. Usually, colonies which grew on the agar initially inoculated could be subcultured, but sometimes they could not. At other times, colonies were not seen on the agar initially inoculated but appeared on the subcultured plate.     

Mycoplasma iowae species-specific DNA probe

A Mycoplasma iowae (MI) species-specific DNA probe (designated pMI-2) of 6.0 kbp (kilobase pairs) was isolated from an MI strain I-695 genomic library prepared in plasmid pUC8 and Escherichia coli strain JM83. When labeled with [32]P by nick translation, the probe hybridized in dot blot assays with 6 reference strains and 8 field isolates of MI but not with 16 other known species of avian mycoplasmas. The pMI-2 probe detected a minimum of 1.5 ng of MI strain I-695 chromosomal DNA. Under identical conditions of hybridization, the probe did not hybridize with a high concentration (200 ng) of M. gallisepticum or M. synoviae chromosomal DNA.     

Characterization of turkey coronavirus from turkey poults with acute enteritis.

The present study was to characterize turkey coronavirus associated with turkey poult enteritis and mortality. Intestinal contents or intestines from affected turkey poults and inoculated turkey embryos contained coronaviruses as revealed by electron microscopy or were positive for turkey coronavirus by immunofluorescent antibody assay. Sucrose density gradient ultracentrifugation of the virus-containing intestinal homogenate yielded two opalescent bands corresponding to the buoyant densities of 1.14-1.15 and 1.18-1.20 g/ml, respectively. Coronaviral particles from intestinal contents or the sucrose density gradient preparation were mainly spherical in shape and had envelope and central depression. They were surrounded by a fringe of regularly spaced petal-shaped projections attached to the particles by a short stalk. Purified viruses hemagglutinated rabbit erythrocytes with a titer of 16. Major protein bands of purified viruses analyzed by SDS-PAGE were located at 200, 100-110, 50-60, and 30-35 kDa. The patterns of protein bands were consistent with those of Minnesota or Quebec turkey coronavirus isolates. A 568 bp nucleotide fragment of turkey coronavirus spike protein gene was amplified from RNA of inoculated turkey embryo intestine or purified virus. Sequence analysis of the 568 bp PCR product revealed high degree of identity with the corresponding spike protein gene sequence of human and bovine coronaviruses. The results indicated that turkey coronavirus was associated with turkey poults with acute enteritis.     

Specific mucosal IgA immunity in turkey poults infected with turkey coronavirus

The objective of this study was to elucidate the kinetics and magnitudes of specific IgA antibody responses in intestines of turkey poults infected with turkey coronavirus (TCV). Turkey poults were orally inoculated with TCV at 10 days of age. Intestinal segment cultures were administered for duodenum, jejunum, and ileum and the IgA antibody responses were analyzed at 1, 2, 3, 4, 6, or 9 weeks post-infection (PI) in two different experiments. The kinetics of virus-specific IgA antibody responses in duodenum, jejunum, and ileum were similar: gradually increased from 1 week PI, reached the peak at 3 or 4 weeks PI, and declined afterward. The virus-specific IgA antibody responses in duodenum, jejunum, and ileum showed negative correlation with duration of TCV antigen in the corresponding locations of intestine with Spearman's correlation coefficient of -0.85 (p=0.034), -0.74 (p=0.096), and -0.75 (p=0.084), respectively. Moreover, the virus-specific IgA antibody responses in serum were positively correlated with that of duodenum (coefficient=0.829, p=0.042), jejunum (coefficient=0.829, p=0.042), and ileum (coefficient=0.771, p=0.072) segment cultures, suggesting that the induction of specific IgA response in serum was predictive of an IgA response in intestine. The results indicate that intestinal mucosal IgA antibodies to TCV are elicited in turkeys following infection with TCV. The local mucosal antibodies may provide protective immunity for infected turkeys to recover from TCV infection.     

Efficacy of lincomycin-spectinomycin water medication on Mycoplasma meleagridis airsacculitis in commercially reared turkey poults

A field trial was conducted to compare the efficacy of a combination of the drugs lincomycin and spectinomycin (LS) with Tylan (tylosin, T) against Mycoplasma meleagridis (MM) airsacculitis in 50,320 commercially reared turkey poults in Ohio. Both drugs were administered at 2 g per gallon of drinking water for the first 5 days of life. The poults were allotted randomly to two treatment groups with 8 or 5 replicates each. Initially, 250 poults were weighed, necropsied, and examined microbiologically and grossly for airsacculitis. At 3 weeks of age, 33 poults from each replicate were randomly selected, necropsied, and examined for airsacculitis. The data indicate that LS is superior to T as an aid in the control of MM airsacculitis in poults, as reflected by fewer air-sac lesions and greater improvement in weight gain (P less than 0.05).     

Salt poisoning in turkey poults

A 4% mortality in 5-to-11-day-old turkey poults was attributed to 1.85% sodium chloride in the feed. The syndrome included peracute respiratory distress, ascites, and sudden death that resembled peracute heart failure. Clinical signs were observed only in the final phase of the toxicity, but progressive histologic lesions were found. Live, apparently unaffected poults showed increases in intracellular glycogen and cytoplasmic granularity, loss of striation, and early mild intercellular myocardial edema; similar but more severe histologic lesions were seen in live, ascites-affected poults. The ascites-affected poults had hydropericardium and hydrothorax which seemed to develop just minutes before death. Ultrastructurally, focal areas of myocardial cells exhibited myofibrillar disarray, lysis of myofilaments, widened Z-bands, and dilation of sarcoplasmic reticulum.     

Comparison of strains of Mycoplasma iowae

Comparison of biochemical test results and protein electrophoretic patterns of 21 strains of Mycoplasma iowae indicated that all were similar. Comparison of agglutination test results indicated marked within-species antigenic variation. None of 21 antigens prepared from different strains were effective in demonstrating turkey antibody against five reference strains. Examination of sera from turkeys exposed by intra-air-sac inoculation to two pathogenic strains also indicated antigenic variation. Neither the M. iowae type-strain, Iowa 695, nor the other reference strains were effective in demonstrating antibody against both strains used to expose the turkeys. These findings suggest that antigenic variation may be a major problem in effective serodiagnosis of M. iowae infections.     

Furazolidone toxicity in neomycin-treated turkey poults

Furazolidone (FZ) toxicity was evaluated in turkey poults treated with neomycin at a dose of 20 mg/kg body weight for 5, 10, or 26 days. Neomycin treatment had no effect on FZ-induced anorexia, delayed the onset of altered electrocardiographic patterns by approximately 1 week, and did not significantly affect the development of FZ-induced cardiomyopathy. Data indicated that FZ toxicity is not significantly altered by the gut microflora.     

Enteric viruses in diarrheic turkey poults

Thirty-three intestinal samples from 10-to-21-day-old diarrheic turkey poults were examined for the presence of enteric viruses by electron microscopy. Samples originated from 32 flocks in six commercial operations located in six states. Mortality in these flocks ranged from 3 to 15%, and birds from recovered flocks varied greatly in size. Rotavirus-like agents (RVLA) were the most common viruses associated with diarrhea outbreaks in the flocks examined, occurring in five out of six operations. Other viruses detected either singly or in combination, in order of prevalence, were astroviruses, reoviruses, rotaviruses, enteroviruses, and adenoviruses. With the exception of RVLA and rotaviruses, the other viruses were identified solely on the basis of morphology. Salmonellae were isolated from only one of the intestinal samples. By electron microscopy, RVLA were morphologically indistinguishable from rotaviruses, occurring as both 55-nm single-shelled and 70-nm double-shelled particles. However, immune electron microscopy was useful for antigenic differentiation of these two viruses. Turkey rotaviruses reacted with antisera to porcine and bovine rotaviruses, whereas turkey RVLA did not. Neither turkey rotaviruses nor RVLA reacted with antisera to porcine para-rotavirus or an antigenically distinct bovine rotavirus (bovine rotavirus-like agent). Similarly, convalescent anti-turkey RVLA serum (from recovered specific-pathogen-free poults) reacted with homologous virus but did not react with mammalian or avian rotaviruses or reoviruses. Further, RVLA were found to possess RNA electrophoretic migration patterns unlike those of conventional rotaviruses or reoviruses. This trait was used as an additional means of differentiating these viruses.     

Neonatal osteomyelitis associated with Staphylococcus aureus in turkey poults

A case of Staphylococcus aureus infection causing osteomyelitis in young turkey poults is described. Mortality during the first week after hatching was 12.6%. Poults showed leg weakness, inflammation of all four toes, swelling of feet and hock joints, and osteomyelitis of the proximal tibiotarsus. Staphylococcus aureus was isolated from exudate in the hock joints and footpads. Granulocytic infiltration and colonies of gram-positive coccoid bacteria compatible with S. aureus were found on microscopic examination of the lesions. Toe trimming after hatching is believed to have provided a portal of entry for S. aureus, which resulted in infection of the toes and spread along tendons to joints and bones of the leg. Neonatal staphylococcal osteomyelitis should be considered when recently placed turkey flocks experience increased mortality, especially if they develop severe swelling and inflammation of toes following trimming and have enlarged swollen feet, tendons, or joints.     

Bilateral malacia associated with sodium poisoning in turkey poults

Improper cleaning of the water storage tank resulted in a toxic concentration of sodium in drinking water in a commercial turkey flock. Within the first week after placement 40% of the birds in the flock died. Clinically, poults were depressed and weak, huddled together, and reluctant to walk. At necropsy the birds had crops and gizzards filled with rice hulls, moderately swollen livers, distended gall bladders, and congested lungs. Neither ascites nor round heart was observed. The major microscopic lesion was multifocal symmetrical malacia of brain and spinal cord. Laboratory results revealed a high concentration of sodium in water (2340 mg/liter). The concentration of sodium in brain and liver ranged from 1870 to 2680 (mean = 2185; SD = 321.5) mg/liter wet weight and from 1810 to 2360 (mean = 2191.67; SD = 193.2) mg/liter wet weight, respectively, whereas the normal expected sodium concentration in the brain and liver tissues from young turkeys (< 7 days old) that were submitted for other causes averaged 1233 and 983 mg/liter wet weight, respectively. Based on the histological and toxicological results, a diagnosis of salt poisoning was made. This case investigation demonstrated that sodium analysis of brain and liver are diagnostically useful when confirming sodium poisoning in young turkeys.