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Chronic Respiratory Disease of Ducks*
CHRONIC RESPIRATORY DISEASE OF DUCKS
sexes have been brooded separately. In both groups of data the deviations in average weight of the samples were no greater than expected by chance. This method has been used to follow the growth rate of chickens in large pens from the fifth to the eleventh week after hatching. It is a convenient method for determining when a group of broilers have reached a specified weight. Research on growth rate under large volume condi-
397
tions is made possible by this method of sampling. ACKNOWLEDGMENT The data included in this report were collected on "contract" broiler farms of Nichols Poultry Farm, Incorporated, Kingston, New Hampshire. The author wishes to express his appreciation to J. R. Weatherbee, J. S. Higgins and B. J. Banks for their assistance and suggestions in making these tests.
J. E.
FAHEY
Connaught Medical Research Laboratories, University of Toronto, Toronto, Ont., Canada (Received for publication July 22, 1954)
A
LTHOUGH chronic respiratory dis' ease (CRD) in chickens and turkeys has been described on many occasions, little attention has been paid to a similar condition occurring in ducks. Dougherty and Fabricant (1953) have shown that CRD "agents" isolated from chickens or turkeys will not cause CRD in ducks and furthermore, that the reported causative agent of "New Duck Disease," Pfeifferella antipestifer will not cause CRD in chickens. This preliminary report describes an outbreak of a chronic respiratory disease in ducks from which two different agents were isolated. The outbreak occurred on a commercial duck farm in Ontario consisting of 2000 breeders and 10,000 young ducks of various ages. The disease was first noticed in a group of 2 week old ducklings and was characterized by depression, sneezing and some head shaking in the majority of birds. Approximately 2 - 3 % of the af* This project was supported jointly by the Ontario Veterinary College and the Connaught Medical Research Laboratories.
fected birds were suffering from sore eyes similar to that observed in chickens with CRD. The losses were less than 5% during the 6-8 week course of the disease. However, the infection caused the birds to be unthrifty and they required extra time to reach market weight. There were no chickens or turkeys on the premises where this outbreak occurred. Clinically this condition was different from that observed in duck virus hepatitis by Levine and Fabricant (1950). Ten sick birds, 6 weeks of age, were autopsied and the gross pathological picture was typical of that observed in CRD of chickens. There was extensive pericardial and perihepatic exudation extending in some cases to the abdominal air sacs. All birds exhibited some degree of pneumonic consolidation and two birds showed a caseous pneumonia. Bacteriological examination of the blood and tissues of these birds failed to reveal any bacterial pathogens. Lungs and trachea were treated as previously described by Fahey and Crawley
Downloaded from http://ps.oxfordjournals.org/ by guest on May 7, 2015
Chronic Respiratory Disease of Ducks*
398
J. E. FAHEY TABLE 1.—Mortality pattern of the virus isolated from the infected ducks
Passage
Inoculum
1
Duck #1 2 3 4 5 6 7 8 9 10
Inoculation details
Remarks
PN diluent1; YS route; 6 eggs/group
2
3
4
5
6
7
8
1 1
PPLO isolated PPLO isolated
1 1*
2*
1*
PNS diluent 2 ; CAS route; 10 eggs/group
3
#8 9
PNS diluent; CAS route; 6 eggs/group
4
#8
PNS diluent; CAS route; 10 eggs/group
1 1
1 5
1 2* 4
1 1
1 2
1* 2
3* 1
2
8
1 1 3* 1* 2 6* 6*
1
1* 2
1*
1*
PPLO isolated No PPLO isolated No PPLO isolated No PPLO isolated
1 1 1
1 2
PN: diluent containing penicillin 100 units/ml. and neomycin 0.5 gm./ml. PNS: diluent PN+streptomycin 5 mgm./ml. * Numbers so marked represent eggs used in the next serial transfer.
(1954a) and injected into 7 day eggs by the yolk sac (YS) route. The results of this and some of the further studies in eggs are shown in Table 1. Yolk sac membranes from isolations 1, 2, 4, 5, 7, 8 and 10 were injected each into two 8 week old turkeys by the intrasinus route. No sinusitis was observed in these birds during a 3 month observation period. The embryos which died were opened using sterile precautions and examined. Hemorrhage and edema were the most prominent characteristics of the dead embryos and YS membranes. Yolk sac membranes from groups 1, 2, 7, 8, 9 and 10 were used for attempted isolation of a pleuropneumonia-like organism (PPLO). The procedure followed was identical with that adopted by Fahey and Crawley (1954b) for the isolation of PPLO from chickens. After 3 passages in the phenol red broth medium, some
growth was obtained from 1, 2 and 7 as determined by the examination of smears stained by the Giemsa method, as well as by the fermentation reactions. Morphologically, the organism isolated was similar to the other avian PPLO but this strain did not ferment sucrose, although maltose and dextrose were weakly fermented. Sucrose, mannitol and lactose remained negative during a 2 week observation period for each of 5 serial passages. The growth obtained in the phenol red broth was very scanty and could not be used as an antigen in the PPLO hemagglutination-inhibition (H-I) test described by Fahey and Crawley (1954c). In an attempt to isolate a virus, the chorioallantoic fluid from the first transfer in eggs was passaged 5 times by the chorioallantoic sac (CAS) route in 9 day embryos in the presence of streptomycin (5 mgm./ml.). The sixth passage of this
Downloaded from http://ps.oxfordjournals.org/ by guest on May 7, 2015
1
3 4 5 1
2
#4 8 9 10
2
Day after inoculation (deaths) 1
CHRONIC RESPIRATORY DISEASE OF DUCKS
399
months after the outbreak occurred sera from the two year old breeders (10), 6 month (5), and 8 week (5) ducks were tested for PPLO H-I antibodies in the same way, and all were negative. These sera were likewise negative for the presence of Newcastle H-I and infectious bronchitis antibodies. The results presented above indicate that two distinct entities were isolated from ducks suffering from a chronic respiratory disease. The failure to demonstrate PPLO H-I antibodies in the sera of sick and recovered ducks may be due either to antigenic differences between PPLO from ducks and those of chickens or turkeys, or to the possibility that the PPLO isolated played no role in the infectious process and were merely saprophytic. The ability of the virus agent isolated to produce CRD in chickens is of interest since it may point to a common denominator underlying the chronic respiratory conditions observed in chickens, turkeys and ducks.
Two groups of 20 one week old chicks were infected by the intranasal (IN) or intraperitoneal (IP) route with the second CAS passage of this viral agent. Both groups developed a respiratory condition which persisted about 9 weeks. Eight deaths occurred in the IN group and 5 in the IP group, all occurring 3-10 days after inoculation. At autopsy, these birds which died showed pneumonia and some flecks of yellowish-brown exudate over the pericardium, liver and abdominal air sacs. During the 10 week observation period, there were only two deaths in a group of 60 uninfected controls. The sera obtained from the original 10 ducks, from which a PPLO was isolated, possessed no H-I antibodies against either turkey or chicken strains of PPLO. Ten
Dougherty, E., and J. Fabricant, 1953. An attempt to demonstrate an etiologic relationship between "New Duck Disease" and chronic respiratory disease of chickens. Proc. 25th Ann. Meet. Lab. Workers Pullorum Dis. Cont. Amherst, Mass. Fahey, J. E., and J. F. Crawley, 1954a. Studies on chronic respiratory disease of chickens. II. Isolation of a virus. Canad. J. Comp. Med. 18: 13-21. Fahey, J. E., and J. F. Crawley, 1954b. Studies on chronic respiratory disease of chickens. III. Egg transmission of a pleuropneumonia-like organism. Canad. J. Comp. Med. 18: 67-75. Fahey, J. E., and J. F. Crawley, 1954c. Studies on chronic respiratory disease of chickens. IV. A hemagglutination inhibition diagnostic test. Canad. J. Comp. Med. 18: 264-272. Levine, P. P., and J. Fabricant, 1950. A hithertoundescribed virus disease of ducks in North America. Cornell Vet. 40: 71-86. Walker, R. V. L., and C. L. Bannister, 1953. A filterable agent in ducks. Canad. J. Comp. Med. 17: 248-250.
REFERENCES
Downloaded from http://ps.oxfordjournals.org/ by guest on May 7, 2015
agent had an LD 60 of - 7 . 5 2 . All CAS passages of this material were tested for hemagglutinating ability and were found negative. The failure of the CAS fluids to agglutinate chicken red blood cells as well as certain other characteristics indicate that this virus is different from that obtained from ducks by Walker and Bannister (1953). Three attempts to propagate a PPLO from this and later passages gave negative results. The properties of this agent, which is believed to be a virus, are essentially the same as those described by Fahey and Crawley (1954a) for the CRD virus of chickens. The duck virus grew following inoculation by the YS and CAS routes and produced pocks on the chorioallantoic membranes of 8-11 day embryos. The fact that this virus passed through a Seitz EK filter pad without significant loss of titer, and grew well in fertile hens eggs in the presence of streptomycin, aureomycin or terramycin in amounts which are inhibitory for PPLO, eliminates the possibility of the embryo mortality being due to the PPLO described in the preceding paragraph.
sexes have been brooded separately. In both groups of data the deviations in average weight of the samples were no greater than expected by chance. This method has been used to follow the growth rate of chickens in large pens from the fifth to the eleventh week after hatching. It is a convenient method for determining when a group of broilers have reached a specified weight. Research on growth rate under large volume condi-
397
tions is made possible by this method of sampling. ACKNOWLEDGMENT The data included in this report were collected on "contract" broiler farms of Nichols Poultry Farm, Incorporated, Kingston, New Hampshire. The author wishes to express his appreciation to J. R. Weatherbee, J. S. Higgins and B. J. Banks for their assistance and suggestions in making these tests.
J. E.
FAHEY
Connaught Medical Research Laboratories, University of Toronto, Toronto, Ont., Canada (Received for publication July 22, 1954)
A
LTHOUGH chronic respiratory dis' ease (CRD) in chickens and turkeys has been described on many occasions, little attention has been paid to a similar condition occurring in ducks. Dougherty and Fabricant (1953) have shown that CRD "agents" isolated from chickens or turkeys will not cause CRD in ducks and furthermore, that the reported causative agent of "New Duck Disease," Pfeifferella antipestifer will not cause CRD in chickens. This preliminary report describes an outbreak of a chronic respiratory disease in ducks from which two different agents were isolated. The outbreak occurred on a commercial duck farm in Ontario consisting of 2000 breeders and 10,000 young ducks of various ages. The disease was first noticed in a group of 2 week old ducklings and was characterized by depression, sneezing and some head shaking in the majority of birds. Approximately 2 - 3 % of the af* This project was supported jointly by the Ontario Veterinary College and the Connaught Medical Research Laboratories.
fected birds were suffering from sore eyes similar to that observed in chickens with CRD. The losses were less than 5% during the 6-8 week course of the disease. However, the infection caused the birds to be unthrifty and they required extra time to reach market weight. There were no chickens or turkeys on the premises where this outbreak occurred. Clinically this condition was different from that observed in duck virus hepatitis by Levine and Fabricant (1950). Ten sick birds, 6 weeks of age, were autopsied and the gross pathological picture was typical of that observed in CRD of chickens. There was extensive pericardial and perihepatic exudation extending in some cases to the abdominal air sacs. All birds exhibited some degree of pneumonic consolidation and two birds showed a caseous pneumonia. Bacteriological examination of the blood and tissues of these birds failed to reveal any bacterial pathogens. Lungs and trachea were treated as previously described by Fahey and Crawley
Downloaded from http://ps.oxfordjournals.org/ by guest on May 7, 2015
Chronic Respiratory Disease of Ducks*
398
J. E. FAHEY TABLE 1.—Mortality pattern of the virus isolated from the infected ducks
Passage
Inoculum
1
Duck #1 2 3 4 5 6 7 8 9 10
Inoculation details
Remarks
PN diluent1; YS route; 6 eggs/group
2
3
4
5
6
7
8
1 1
PPLO isolated PPLO isolated
1 1*
2*
1*
PNS diluent 2 ; CAS route; 10 eggs/group
3
#8 9
PNS diluent; CAS route; 6 eggs/group
4
#8
PNS diluent; CAS route; 10 eggs/group
1 1
1 5
1 2* 4
1 1
1 2
1* 2
3* 1
2
8
1 1 3* 1* 2 6* 6*
1
1* 2
1*
1*
PPLO isolated No PPLO isolated No PPLO isolated No PPLO isolated
1 1 1
1 2
PN: diluent containing penicillin 100 units/ml. and neomycin 0.5 gm./ml. PNS: diluent PN+streptomycin 5 mgm./ml. * Numbers so marked represent eggs used in the next serial transfer.
(1954a) and injected into 7 day eggs by the yolk sac (YS) route. The results of this and some of the further studies in eggs are shown in Table 1. Yolk sac membranes from isolations 1, 2, 4, 5, 7, 8 and 10 were injected each into two 8 week old turkeys by the intrasinus route. No sinusitis was observed in these birds during a 3 month observation period. The embryos which died were opened using sterile precautions and examined. Hemorrhage and edema were the most prominent characteristics of the dead embryos and YS membranes. Yolk sac membranes from groups 1, 2, 7, 8, 9 and 10 were used for attempted isolation of a pleuropneumonia-like organism (PPLO). The procedure followed was identical with that adopted by Fahey and Crawley (1954b) for the isolation of PPLO from chickens. After 3 passages in the phenol red broth medium, some
growth was obtained from 1, 2 and 7 as determined by the examination of smears stained by the Giemsa method, as well as by the fermentation reactions. Morphologically, the organism isolated was similar to the other avian PPLO but this strain did not ferment sucrose, although maltose and dextrose were weakly fermented. Sucrose, mannitol and lactose remained negative during a 2 week observation period for each of 5 serial passages. The growth obtained in the phenol red broth was very scanty and could not be used as an antigen in the PPLO hemagglutination-inhibition (H-I) test described by Fahey and Crawley (1954c). In an attempt to isolate a virus, the chorioallantoic fluid from the first transfer in eggs was passaged 5 times by the chorioallantoic sac (CAS) route in 9 day embryos in the presence of streptomycin (5 mgm./ml.). The sixth passage of this
Downloaded from http://ps.oxfordjournals.org/ by guest on May 7, 2015
1
3 4 5 1
2
#4 8 9 10
2
Day after inoculation (deaths) 1
CHRONIC RESPIRATORY DISEASE OF DUCKS
399
months after the outbreak occurred sera from the two year old breeders (10), 6 month (5), and 8 week (5) ducks were tested for PPLO H-I antibodies in the same way, and all were negative. These sera were likewise negative for the presence of Newcastle H-I and infectious bronchitis antibodies. The results presented above indicate that two distinct entities were isolated from ducks suffering from a chronic respiratory disease. The failure to demonstrate PPLO H-I antibodies in the sera of sick and recovered ducks may be due either to antigenic differences between PPLO from ducks and those of chickens or turkeys, or to the possibility that the PPLO isolated played no role in the infectious process and were merely saprophytic. The ability of the virus agent isolated to produce CRD in chickens is of interest since it may point to a common denominator underlying the chronic respiratory conditions observed in chickens, turkeys and ducks.
Two groups of 20 one week old chicks were infected by the intranasal (IN) or intraperitoneal (IP) route with the second CAS passage of this viral agent. Both groups developed a respiratory condition which persisted about 9 weeks. Eight deaths occurred in the IN group and 5 in the IP group, all occurring 3-10 days after inoculation. At autopsy, these birds which died showed pneumonia and some flecks of yellowish-brown exudate over the pericardium, liver and abdominal air sacs. During the 10 week observation period, there were only two deaths in a group of 60 uninfected controls. The sera obtained from the original 10 ducks, from which a PPLO was isolated, possessed no H-I antibodies against either turkey or chicken strains of PPLO. Ten
Dougherty, E., and J. Fabricant, 1953. An attempt to demonstrate an etiologic relationship between "New Duck Disease" and chronic respiratory disease of chickens. Proc. 25th Ann. Meet. Lab. Workers Pullorum Dis. Cont. Amherst, Mass. Fahey, J. E., and J. F. Crawley, 1954a. Studies on chronic respiratory disease of chickens. II. Isolation of a virus. Canad. J. Comp. Med. 18: 13-21. Fahey, J. E., and J. F. Crawley, 1954b. Studies on chronic respiratory disease of chickens. III. Egg transmission of a pleuropneumonia-like organism. Canad. J. Comp. Med. 18: 67-75. Fahey, J. E., and J. F. Crawley, 1954c. Studies on chronic respiratory disease of chickens. IV. A hemagglutination inhibition diagnostic test. Canad. J. Comp. Med. 18: 264-272. Levine, P. P., and J. Fabricant, 1950. A hithertoundescribed virus disease of ducks in North America. Cornell Vet. 40: 71-86. Walker, R. V. L., and C. L. Bannister, 1953. A filterable agent in ducks. Canad. J. Comp. Med. 17: 248-250.
REFERENCES
Downloaded from http://ps.oxfordjournals.org/ by guest on May 7, 2015
agent had an LD 60 of - 7 . 5 2 . All CAS passages of this material were tested for hemagglutinating ability and were found negative. The failure of the CAS fluids to agglutinate chicken red blood cells as well as certain other characteristics indicate that this virus is different from that obtained from ducks by Walker and Bannister (1953). Three attempts to propagate a PPLO from this and later passages gave negative results. The properties of this agent, which is believed to be a virus, are essentially the same as those described by Fahey and Crawley (1954a) for the CRD virus of chickens. The duck virus grew following inoculation by the YS and CAS routes and produced pocks on the chorioallantoic membranes of 8-11 day embryos. The fact that this virus passed through a Seitz EK filter pad without significant loss of titer, and grew well in fertile hens eggs in the presence of streptomycin, aureomycin or terramycin in amounts which are inhibitory for PPLO, eliminates the possibility of the embryo mortality being due to the PPLO described in the preceding paragraph.