Recurrent transient paresis in a turkey flock.

Recurring episodes of extreme leg weakness and associated mortality were documented in a turkey flock at 8 to 15 weeks of age. Flock mortality attributed to posterior paresis was approximately 12%, or 4800 of 40,000 turkeys. Four of six open-confinement units were affected. Gross and histological examinations revealed no significant lesions. Immunology and virology were uninformative. There were no significant differences in serum chemistry between clinically affected and normal turkeys. Testing of feed, water, soil, and tissues revealed no common toxicants. Isolation and supportive care for affected turkeys, both in the laboratory and in the field, frequently resulted in full recovery. Injection of a test group of affected turkeys with Type C botulism antitoxin appeared to enhance recovery. However, repeated attempts to detect botulism toxin in serum, liver, or cecal contents using mouse bioassay procedures were unsuccessful.     

Effect of dietary supplementation with clay‐based binders on biochemical and histopathological changes in organs of turkey fed with aflatoxin‐contaminated diets

This study was carried out to investigate the effect of dietary supplementation with molecular or nano‐clay binders on biochemical and histopathological examination of organs of turkeys fed diets contaminated with aflatoxin B_1. Two hundred and sixteen unsexed 1‐day‐old British United Turkeys were randomly allotted to nine diets in a 3 × 3 factorial arrangement of diets supplemented with no toxin binder, molecular toxin binder (MTB) and nano‐clay toxin binder, each contaminated with 0, 60 and 110 ppb aflatoxin B₁ respectively. There were three replicates per treatment with eight turkeys per replicate. Biochemical analyses, organ weights and histopathological changes of some organs were examined at the end of the study which lasted for 84 days. Turkeys fed diets supplemented with molecular and nano‐binders showed higher (p < 0.001) total serum protein, reduced (p < 0.001) serum uric acid and GGT concentration values when compared with those fed aflatoxin‐contaminated diets supplemented with no binder. Turkeys fed aflatoxin‐contaminated diets supplemented with no binder had increased (p < 0.001) AST and ALT concentration when compared with other treatments. The heaviest (p < 0.001) liver and intestinal weight was noticed with turkeys fed diets supplemented with no binder and contaminated with 110 ppb aflatoxin B₁. Pathologically, there was no visible morphological alteration noticed in all turkeys fed uncontaminated diets and nano‐clay‐supplemented group. Hepatic paleness, hepatomegaly and yellowish discolouration of the liver were observed with turkeys fed diets containing no binder but contaminated with 60 and 110 ppb aflatoxin B1. Intestinal histopathological changes such as goblet cell hyperplasia, villous atrophy and diffuse lymphocytic enteritis were more prominent in turkeys fed diets containing no toxin binder and MTB. In conclusion, there were improved biochemical parameters and reduced deleterious effects of aflatoxin B₁ in turkeys fed diet supplemented with clay binders. However, the improvement was more conspicuous in the nano‐clay‐supplemented group than molecular clay group.     

Turkey coryza: toxin production by Bordetella avium

Twelve strains of Bordetella avium representing isolates from turkeys in the United States, the Federal Republic of Germany, and the Republic of South Africa were tested for toxin production. Sterile filtered sonicates from 9 of 12 strains contained a toxin that was lethal for 7-to-10-day-old poults. Mice were also susceptible to the lethal effects of the toxin. No differences in susceptibility to the toxin were found between Beltsville small white and broad-breasted white poults. The toxin was solubilized by sonication and inactivated by heating at 56 C for 30 min. Treatment with formalin or proteolytic enzymes inactivated the toxin, indicating that it is probably a protein. The evidence suggests that the toxin is involved in the pathogenesis of turkey coryza.     

Influence of Bordetella avium infection on association of Escherichia coli with turkey trachea

Four-week-old Bordetella avium-infected and B avium-free turkeys were inoculated intratracheally with a suspension of fimbriated or nonfimbriated Escherichia coli. Numbers of E coli associated with tracheal sections were determined at postinoculation hour (PIH) 1 or 6. Significantly (P less than 0.05) greater numbers of E coli were isolated from the tracheas of B avium-infected turkeys compared with numbers in B avium-free turkeys. In B avium-free turkeys, tracheal associated E coli were 90% less at PIH 6 compared with that at PIH 1. However, in B avium-infected turkeys, numbers of E coli were not affected by postinoculation time. Seemingly, B avium-infected turkeys had reduced capacity to clear E coli from the trachea.     

Clearance of bacteria in turkeys with Bordetella avium-induced tracheitis

Quantitative clearance of aerosolized Escherichia coli from the trachea, lung, and air sacs was measured in turkeys infected with Bordetella avium. Clearance of E. coli in turkeys with B. avium-induced tracheitis was minimally affected early in infection. Sixteen to 23 days after infection with B. avium, sporadic, mild depressions in clearance of E. coli were observed in the tracheas, which had large areas of deciliated tracheal epithelium or replacement of normal epithelium by immature hyperplastic epithelium or metaplastic squamous epithelium. Clearance of E. coli from the lung and air sacs was minimally affected in turkeys infected with B. avium.     

Mycoplasma gallisepticum infection in wild-type turkeys living in close contact with domestic fowl

Mycoplasma gallisepticum was isolated from 2 wild-type turkeys (Meleagris gallopavo) and 1 domestic turkey living in close contact on a farm in Tehama County, California. Sinusitis was detected in 2 of 14 wild-type turkeys and in 1 of 12 feral broad-breasted bronze turkeys, but in none of several chickens on the premises. The entire mixed flock was captured, sinus aspirates were collected from affected birds, and blood samples were obtained from all birds for serologic testing. Blood samples also were obtained from 10 domestic turkeys on adjacent premises from which breeding stock had been borrowed. The M gallisepticum isolated from sinus aspirates was typed and inoculated into susceptible chickens, resulting in airsacculitis. California wild turkeys with and without histories of exposure to domestic fowl and wild turkeys shipped into California from Texas for release were tested for antibodies to M gallisepticum, using the plate agglutination test. Evidence of M gallisepticum infection was not found in wild turkeys at any location other than the original premises.     

Inclusion-body hepatitis in day-old turkeys

Inclusion-body hepatitis was diagnosed in 1-day-old turkeys experiencing above-average mortality. At necropsy, turkeys appeared anemic and had pale yellow livers. Histopathologic examination of affected livers revealed diffuse hepatic degeneration and multifocal necrosis, with approximately 70% of the hepatocytes containing large, basophilic, intranuclear inclusion bodies. An adenovirus was isolated from affected livers and identified as a group I avian adenovirus by indirect immunofluorescence.     

Inflammation of the nasal gland in domestic turkeys.

A prominent swelling above the eye of range-reared tom turkeys was found to be due to severe inflammation and hyperplasia of the nasal or salt gland. The incidence of affected turkeys was sporadic, and no mortality or other lesions were associated with the condition.     

The Extent and Control of Avian Influenza in Canada

The large variety of influenza A virus types circulating among wild birds in their northern breeding grounds represents a menace to the Canadian poultry industry. The principal victims of avian influenza in the past were turkeys, exceptionally affected were ducks, but never chickens. Influenza in Ontario turkeys reached a peak incidence at the end of the 60's, then it declined steadily to isolated infrequent infections. The decline is attributed to efforts made to avoid contact between domestic turkeys and wild birds. The prospect of controlling avian influenza by vaccination is discounted, and it is recommended to place more emphasis on isolation of the turkeys and improved sanitation on the farms.     

Turkey coryza: selected tests for detection and neutralization of Bordetella avium heat-labile toxin

Bordetella avium heat-labile toxin (HLT) was lethal for poults, mice, and embryonating chicken eggs. It produced hemorrhagic lesions in turkey and guinea pig skin. Antiserum made in turkeys neutralized the lethality of the toxin and its ability to produce hemorrhagic skin lesions. Further, antiserum against HLT of an Ohio strain neutralized lethality of HLT of strains from Iowa, North Carolina, and West Germany. The antiserum did not neutralize lethality of HLT from B. bronchiseptica. Bordetella avium HLT was not ciliostatic for turkey tracheal-ring cultures and did not stimulate adenyl cyclase activity using mouse adrenal cell cultures.     

Pasteurella anatipestifer infection in commercial meat-type turkeys in California

A disease outbreak characterized by respiratory signs, occasional neurologic signs, and increased mortality in commercial meat turkeys from four separate companies in central California was investigated in the late summer and early fall of 1986. The disease syndrome affected turkeys from 6 to 15 weeks of age and caused a severe fibrinous pericarditis, perihepatitis, and airsacculitis. Bacteriologic and serologic examinations as well as virus- and chlamydia-isolation attempts initially failed to implicate an etiologic agent. Eventually culture attempts were made in a 5% CO2 incubator, resulting in isolation of Pasteurella anatipestifer. The disease syndrome was reproduced in young turkeys and broiler chicks inoculated with the organism.     

Effect of crude protein concentration and dietary electrolyte balance on litter quality,foot pad dermatitis,growth performance and processing yields in two medium heavy turkey hybrids

1. An experiment was conducted to investigate the effect of crude protein (CP) concentration and dietary electrolyte balance (DEB) on growth performance, processing yields, litter quality and foot pad dermatitis (FPD) in male turkeys from two commercial hybrids. Soya bean meal was replaced by vegetable protein sources selected for lower K concentrations to lower DEB in order to improve litter quality and subsequent quality of foot pads.

2. Effects of CP on litter friability and wetness were not consistent during the production period. FPD in turkeys fed on diets with low CP was significantly lower than FPD in turkeys fed on diets with high CP until 84 d. Growth performance was adversely affected at low CP. Processing yields were not affected by CP.

3. Litter was significantly dryer in pens of turkeys fed on diets with low DEB than in pens of turkeys fed on diets with high DEB. FPD in turkeys fed on diets with low DEB was significantly lower than in turkeys fed on diets with high DEB. Growth performance and processing yields were adversely affected at low DEB.

4. FPD in turkey hybrid A was higher than in turkey hybrid B at 28 d of age. Thereafter, no differences in FPD between turkey hybrids were observed. Growth performance and processing yields were not affected by turkey hybrid.

5. Overall, a significant interaction effect of CP × DEB was observed for FCR: in turkeys fed on the high DEB treatment, FCR of turkeys fed on the high CP diets was lower than FCR of turkeys fed on the low CP (LCP) diets whereas on the low DEB treatment, FCR was not affected by CP treatment.

6. It was concluded that litter quality can be improved and FPD may be decreased in turkeys fed on diets containing lower CP and DEB levels.     

A new serotype of Pasteurella multocida associated with fowl cholera

Gel-diffusion precipitin tests demonstrated an additional Pasteurella multocida serotype, designated serotype 16. Isolate P-2723, antigenically distinct from the other (previously reported) 15 serotypes, was from a turkey affected with fowl cholera. This serotype is not widely distributed. Isolate P-2723 was of mild virulence in turkeys, resulting in local infections in the hock joint and sternal bursa of only 1 of 9 turkeys exposed.     

Characterization of a naturally occurring infection of a Mycoplasma gallisepticum house finch-like strain in turkey breeders

An outbreak of Mycoplasma gallisepticum (MG) in commercial turkeys involving very mild clinical signs was difficult to confirm by routine methods. In the first part of this study (trial A), we conducted a bioassay to increase the likelihood of detecting MG. Susceptible turkeys were inoculated with sinus exudates from four different affected commercial turkey flocks. Turkeys were evaluated for clinical signs, as well as by serology and culture of tracheal swabs, at 21 and 42 days postchallenge. An MG isolate from one of the sinus exudates used for inoculation, designated K5054, was very similar to isolates from house finches when characterized by random amplified polymorphic DNA analysis as well as DNA sequence analysis of portions of the phase-variable putative adhesin protein (pvpA) gene, a lipoprotein gene, and the cytadhesin gapA/mgc1 gene. The turkeys inoculated with the K5054 sinus exudate seroconverted in the absence of severe clinical signs. There was a single reisolation of K5054 from these turkeys 42 days postchallenge. Susceptible contact turkeys were commingled with the K5054-inoculated turkeys at 49 days postchallenge. We found no evidence of transmission of MG to the contacts by culture or serology at 7, 21, or 35 days after commingling. In the second part of this study (trial B), we challenged the contacts and K5054 sinus exudate-inoculated turkeys from trial A with virulent R strain 88 days after the K5054 sinus exudate inoculation. On necropsy 10 days postchallenge, the evaluation of gross and microscopic lesions, serology, and culture showed that the turkeys previously inoculated with K5054 sinus exudate were protected against disease and reinfection.     

Avian influenza epidemic in Italy due to serovar H7N1

Beginning at the end of March 1999, a syndrome characterized by severe depression, anorexia, fever, and respiratory and enteric symptoms appeared in flocks of turkeys and, to a lesser extent, of chickens in the densely populated poultry-rearing regions of northeast Italy. The disease was characterized by sinusitis, tracheitis, peritonitis, and pancreatitis. The mortality varied between 5% and 90%. The disease was diagnosed as low pathogenic avian influenza, H7N1 serotype. After a summer period of declining cases, the disease reappeared in autumn exclusively in turkeys. Since the middle of December 1999, many farms of chickens, turkeys, and guinea fowl were abruptly affected by a highly pathogenic H7N1 virus, with very severe depression and mortality up to 100% in a few days. By the end of March 2000, nearly 500 farms, representing over 15 million birds, were affected or depopulated. To date, control measures have focused on improved biosecurity measures. Vaccine was not allowed, but its use was debated.     

Articular aspergillosis of hip joints in turkeys

Aspergillosis is an important cause of morbidity and mortality in birds. Turkey poults are known to be particularly susceptible to fungal infection. Although the respiratory tract is the most commonly affected, dissemination can occur into virtually any organ. Here, we report an unusual outbreak of articular aspergillosis in a flock of meat turkeys with clinical signs of lameness. Between 7 and 11 weeks of age, turkeys had severe granulomatous osteoarthritis of the hip joints with necrosis of the femur head. Fungal morphology and PCR amplification and sequencing of the first ITS1-5.8S-ITS2 rDNA region identified Aspergillus fumigatus as the infectious agent. Concurrently, Staphylococcus spp. was isolated from the hip joints, which may have promoted the tropism of the fungus. Mild respiratory tract aspergillosis was observed in only one case. The findings suggest that fungal arthritis may present a specific disease entity in turkeys and should be considered as further cause of lameness in turkeys.     

Foot pad dermatitis develops at an early age in commercial turkeys

1. A field experiment was conducted to identify the macroscopic and histological changes associated with the development of foot pad dermatitis (FPD) in growing turkeys. Two affected and two unaffected turkeys were sampled weekly from 1 to 8 and at 10 and 21 weeks of age. 2. At one week old, birds with external signs of FPD (surface skin discolouration) showed abnormal cellular changes of the foot pad integument. As the flock aged the reactions intensified, with one sample exhibiting a fully developed macroscopic lesion at 3 weeks. 3. Major pathological changes had occurred by 6 weeks and all turkeys with external signs of lesions had fully developed microscopic inflammatory cellular lesions. From 6 weeks of age onwards lesions were increasingly numerous and became more overtly necrotic. 4. Externally normal foot pads showed microscopic evidence of lesions after the turkeys reached 4 weeks. 5. We conclude that FPD lesions become severe over a short period of time and at a very early age.     

Relative humidity at moderate ambient temperatures: its effect on male broiler chickens and turkeys

1. The effect of relative humidity (RH, 40% to 75%) at moderate ambient temperatures (Ta, 28 degrees and 30 degrees C) on the performance and thermoregulation of male broiler chickens and turkeys was studied at the age of 4 to 8 weeks. 2. Weight gain and food intake of male broiler chickens were significantly higher at 60% to 65% RH but food conversion efficiency was not affected by RH. In male turkeys, no effect of RH on performance was recorded. 3. Both chickens and turkeys controlled body temperature at normothermic levels during exposure to the experimental environmental conditions. 4. The rate of panting estimated from blood pH and pCO2 was lower in chickens exposed to 28 degrees C than to 30 degrees C. In turkeys, the rate was lower than that recorded in chickens at both Ta(s). 5. Plasma T3 was positively and significantly correlated with food intake. 6. It may be concluded that RH plays a role in the performance of chickens exposed to 30 degrees and 28 degrees C. whereas male turkeys must respond to RH at Ta >30 degrees C.     

Late clinical expression of lameness related to associated osteomyelitis and tibial dyschondroplasia in male breeding turkeys.

A sudden outbreak of lameness related to transport stress is described in a flock of male breeding turkeys. Most of the affected turkeys exhibited obvious unilateral leg disorders. All were affected with tibial or metatarsal dyschondroplasia with at least one lesion associated with a large focus of necrosis. By histological examinations, bone lesions showed the typical feature of osteomyelitis. The inflammatory bone lesions appeared at only single isolated sites and were always associated with obvious sequestra of dyschondroplastic retained cartilage. Osteomyelitis seems to be an unexpected acute complication of previous dyschondroplasia in relation with different breeding stress situations. The resulting pain of the associated lesions could be the main cause of clinical expression of lameness. The pathogenesis of the phenomenon remains uncertain.     

Outbreak of cutaneous form of poxvirus on a commercial turkey farm caused by the species fowlpox

The present report documents the occurrence of a poxvirus infection in commercial meat turkeys. The affected farm had six flocks, with a total of 11,680 birds at different ages; birds from two of these flocks were affected. The clinical picture was characterized by severe epithelial lesions and proliferations on the head and neck regions as reported for the cutaneous form of poxvirus infection. Except for these lesions, no adverse clinical signs or gross pathologic lesions were observed. Only a low number of birds was affected (n = 20) and no increase of mortality could be seen. Bacteriologic investigations from the lesions revealed multiresistant Staphylococcus aureus. Eosinophilic inclusions (Bollinger bodies) in histologic examinations in the cytoplasm of keratinocytes were noticeable. Typical pox virions were demonstrated by electron microscopy, and poxvirus was isolated on the chorioallantoic membrane of specific-pathogen-free chicken eggs. Further identification of the poxvirus species was carried out by PCR and sequencing, revealing an infection with the species fowlpox. Layers in vicinity of the turkey farm that also were affected by fowlpox were considered as potential source of infection. Although it is assumed that avian poxviruses are strongly species specific, the present case report reinforces the changing picture of poxvirus infections in turkeys. Furthermore, it supports the assumption of previous data that fowlpox virus has to be seen as recently emerging pathogen in turkeys.