A Survey About The Epidemiology Of This Disease In Young Laying Hen Which Often Appear Paralysis Or Sudden Death Syndrome In Recent Years And A Research About The Cause In Luoyang Region

The primiparous hens paralysis and sudden death syndrome, which often occurson young laying hen at night is commonly found during production in recent years.The invaded hen often appears paralysis, and its short course of disease and quickdeath have brought certain economic losses for chicken production. There is no reporton the systematic and in-depth study about it currently. The epidemiological situationof paralysis and sudden death syndrome of primiparous hens in Luoyang region wasinvestigated in this study, and its cause was also preliminary analyzed in order toprovide help for the prevention and treatment of the disease.1. Epidemiological investigations and laboratory initial diagnosisWe made the epidemiological situation for the invaded chicken flock by themethod of inquiry, phone, visiting and so on.29of49invasion flocks in the surveyoccurred in summer, the incidence was59.3%, which was significantly higher thanthat of the spring, autumn and winter(P<0.05); the incidence of hens in age of150d-170d, higher than other ages, reached73.3%(P<0.05). the number of disease attackedhens during0:00-6:00were127among203diseased chicken in the survey, the ratewere62.6%, which was higher than the incidence of other times in a day(P<0.05);7illblocks from different regions, whose incidence was0.6%, were randomly selectedamong49invasion flocks, however, the incidence of chicken flock from Waterstockade villages in Yichaun reached1.1%, which was higher than the averagelevel(P<0.05), the incidence of other places was lower than1%; Effect evaluations ofseveral control measures of the disease were inquired, results showed that57%peoplebelieve strengthening the night management is more effective, and its efficiency isnotable than others(P<0.05).The clinical symptoms of the invasion hens were paralysis, head droop, weaknessof wing and leg, the diseased hens could feel some stimulus and usually died quickly. The invasion hens appeared good appearance feather, fullness muscle, one egg couldbe touched in its abdomen; Pathological change after autopsy were gore and edema oflung, stomach expanding, proventriculus wall becoming soft and mucosal erosion. Theproventriculus wall of some ill hens had perforation. The pathological section oflesions lung and glandular stomach had pulmonary diffusion bleeding. The collectionsinus of proventriculus expaned, inflammatory cell infiltrated, duct and gland tubuleclosed or disappeared.This disease had some relationship with pasteurella and infectious bronchitisvirus (IBV) based on relevant reports. We had successfully got one strain from1diseased tissue after isolation and identification of pathogen and augmentation ofIBV for21diseased tissues, our test proved the strain were pasteurella, but IBV wasnot amplified yet.2. Monitoring of concentration of ammonia and carbon dioxide in invasionhennery and control henneryWe established18monitoring points in invasion hennery to metry theconcentration of ammonia and carbon dioxide by Environmental MonitoringInstruments. The result showed that the concentration of ammonia in ill hennery isobviously higher than that of the control(P<0.05), however, the difference of theconcentration of carbon dioxide between invasion hennery and control hennery wasnot signifigant(P>0.05).3. Some of the blood index detection of invasion hens and control hensThe blood from ill hens was tested by using blood glucose monitoring kit,determination of insulin and glucagon, blood analysis instrument, The blood viscosityvalue of invasion hen is3.58and the pressure of carbon dioxide in the artery of theinvasion hen is4.93kPa, which is obvious higher than control(P<0.05); The pressureof oxygen which is7.23kPa is obviously lower than control(P<0.05).