THE SEROLOGICAL RESPONSE OF CHICKENS TO OIL EMULSION VACCINES CONTAINING THE V₄ STRAIN OF NEWCASTLE DISEASE VIRUS     

R. Schalkoort    D. M. Morgan  P. B. Spradbrow 《Australian veterinary journal》1982,58(6):260-263

SUMMARY Experiments were conducted with vaccines containing the V₄ strain of Newcastle disease virus (NDV). Both living aqueous vaccines and vaccines consisting of virus incorporated in an oil emulsion were used. The calculated dose of virus contained in the oil emulsion vaccine was 10^8,7 50% embryo infectious doses (EID₅₀) per bird dose. Haemagglutinin inhibition (HI) antibody levels of 8 are presumed protective. One-day-old chicks with low levels of maternal antibody were vaccinated intraocularly with 10^6,3EID₅₀ of live vaccine, and concurrently with oil emulsion vaccine. Presumed protective levels of antibody were present at two weeks post vaccination and were maintained for at least seven weeks longer. When adult birds 15 weeks old with no previous exposure to NDV were vaccinated intraocularly with 10^6,7EID₅₀ per bird, protective levels of antibody were produced within a week. Unvaccinated birds put in contact with the vaccinated birds produced similar antibody levels within 14 days. Revaccination with oil emulsion vaccine after antibody levels had fallen resulted in a rapid response with high levels of antibody. When antibody-free adult commercial birds with an unknown history of exposure to NDV were vaccinated intramuscularly with oil emulsion vaccine, high antibody levels were produced for at least 21 weeks. Concurrent intraocular inoculation with 10^7,0EID₅₀ live virus did not enhance the response. Natural infection of unvaccinated birds occurred during the experiment. This was detected by the presence of HI antibody levels of short duration. When antibody-free commercial birds were inoculated intramuscularly with oil emulsion vaccine containing 10^6,0, 10^7,0, or 10^8,0EID₅₀ per bird dose, 100% of birds inoculated with the highest dose produced presumed protective levels of antibody within two weeks, as compared with a 5-week delay when using the 10^7,0EID₅₀ per bird dose.  相似文献   

Investigation of aberrant positive reactions to serological tests for bovine brucellosis     

B A Rogerson  I R Morgan 《Australian veterinary journal》1986,63(7):227-229

Fifty cattle thought not to be infected with Brucella abortus but giving persistent positive serological reactions, were investigated. It was concluded that only one of these was infected since exhaustive bacteriological examination produced only one isolate of B. abortus (strain 19) and none of the herds of origin was subsequently shown to be infected with brucellosis. Antibody was detected in stifle joint fluid of 15 cattle, which may have been stimulated by the presence of Strain 19 antigen that persisted in collagenous tissue long after the viable organisms had been eliminated.  相似文献   

Vertebral canal and spinal cord mensuration: a comparative study of its effect on lumbosacral myelography in the dachshund and German shepherd dog   总被引：2，自引：0，他引：2  

J P Morgan  M Atilola  C S Bailey 《Journal of the American Veterinary Medical Association》1987,191(8):951-957

One hundred noncontrast spinal radiographic studies followed by myelography were evaluated to compare vertebral canal size and spinal cord location and size in a chondrodystrophic breed (50 Dachshunds) with those variables in a nonchondrodystrophic breed (50 German Shepherd Dogs). Measurements were made of the sagittal diameter (height) of the vertebral canal, sagittal diameter (height) of the spinal cord, and transverse diameter (width) of the spinal cord in the lumbar and sacral regions. Differences were detected in the craniocaudal location of maximal vertebral canal height and maximal spinal cord height. The spinal cords in the Dachshunds terminated further caudally than those in the German Shepherd Dogs. Location of maximal spinal cord width was different between the breeds, consistent with the apparent, more caudal termination of the cord in the Dachshunds. The ratio of spinal cord to vetebral canal heights was notably greater in the Dachshunds than in the German Shepherd Dogs. These differences in vertebral canal and spinal cord mensuration may influence the choice of radiographic technique and its interpretation. Injection sites may be selected further cranially in German Shepherd Dogs (L4-5) than in Dachshunds (L5-6).  相似文献   

CANINE HIP DYSPLASIA     

Joe P.  Morgan  DVM  Vet med dr 《Veterinary radiology & ultrasound》1987,28(1):2-5

It is the purpose of this study to call attention to new bone production that often occurs early in the sequence of pathological changes associated with canine hip dysplasia. New bone production extending to bony remodeling, as well as femoral head subluxation, both occur in the sequence of pathologic changes associated with canine hip dysplasia. Subluxation is considered primary, while osteoarthrosis is a secondary feature, and both are used in the diagnosis of canine hip dysplasia. This report concerns the significance of the presence of a solitary bony osteophyte, or spur, that is frequently evident on the caudal aspect of the femoral neck as viewed on the conventional ventrodorsal projection. This report utilizes findings from pelvic radiographs of 605 dogs (five breeds). There was a greater frequency (54%)of this bony change in cases diagnosed radiographically as dysplastic than in cases diagnosed as normal(15%).Thus, it is suggested that this minimal radiographic change can be used as an indicator of early canine hip dysplasia, especially in the absence of subluxation of the femoral head.  相似文献   

Gossypol as a toxicant in livestock     

S E Morgan 《Veterinary Clinics of North America: Food Animal Practice》1989,5(2):251-262

Many cases of gossypol toxicity have been misdiagnosed. The long-held belief that gossypol toxicity did not occur in ruminants has been a major hurdle to overcome. Field necropsies in which pulmonary congestion and edema were attributed to shipping-fever pneumonia, failure to examine the heart either grossly or microscopically, failure to believe that 200 ppm free gossypol could kill a calf, failure to believe that any age of sheep could suffer gossypol toxicity, and failure to believe that just because you fed the same thing last year, it will not cause a problem this year, all were factors in causing the misdiagnosis of this toxicity. Gossypol toxicity cases diagnosed will increase each year because of increased awareness among veterinarians. Continued research will help to increase our understanding of this multifactored toxin and, possibly, devise ways to detoxify it before it is utilized in a feed. Until then, it will have to be considered because it will continue to be present as a potential toxicant in the feed.  相似文献   

Isolation of Chlamydia psittaci from the genital tract of lambs: a possible link with enzootic abortion of ewes     

K L Morgan  J M Wills  P Howard  R L Williams 《The Veterinary record》1988,123(15):399-400

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MAGNETIC RESONANCE IMAGING OF THE NORMAL EYE AND ORBIT OF THE DOG AND CAT     

Rhea V.  Morgan  DVM  Gregory B.  Daniel  DVM  MS  Robert L.  Donnell  DVM 《Veterinary radiology & ultrasound》1994,35(2):102-108

Magnetic resonance (MR) images of the normal eye and orbit of the dog and cat were acquired. T1-weighted, proton-density, and T2-weighed images were obtained in the oblique dorsal, straight sagittal, and oblique sagittal planes. Signal intensity for the various orbital structures differed among the three resonance techniques. T1-weighted images provided the greatest contrast of the retrobulbar structures. T-1 weighted images also had the highest signal to noise ratio, thereby providing the best anatomic detail. Anatomic components of the globe, retrobulbar structures and ocular adnexa were easily seen in all MR sections. The oblique dorsal and oblique sagittal planes were superior for evaluating the optic nerve in its entirety.  相似文献   

Lamb morbidity in three housed flocks in south-west England during two lambing seasons—farmer versus veterinary monitoring     

L. E. Green  E. Berriatua  K. L. Morgan 《Preventive veterinary medicine》1994,19(3-4):233-240

A 2 year investigation into diseases of early-born, housed lambs was carried out from 1989 to 1991. The mortality, morbidity and sub-clinical disease of housed lambs from three flocks were studied. This paper describes the collection and analysis of morbidity data.

Morbidity was assessed using two techniques. In the first year, a cohort of approximately 80 lambs per flock was observed at regular (7 or 14 day) intervals from birth to slaughter at 10–26 weeks of age. Each lamb was examined using a routine clinical examination carried out by two out of three members of a trained team of veterinarians.

The technique used was thought to be objective and accurate. However, because there was a small proportion (10–12%) of lambs examined there was a lack of information on severely sick lambs and only diseases of prevalence greater than 3.5% had a 95% probability of being identified. This led to a change im the method of data collection in the second year when the whole flock of lambs was observed by farmers and lambs which they considered sick were presented for treatment.

Seventeen clinical entities were detected in the first year; these were primarily mild conditions. In lambs from Cohorts A, B and C, the mortality rates were 11.8%, 10.5% and 1.3%, respectively. In the second year, 16 diseases were observed. Lambs presented by the farmers were overtly sick; 15.3% from Flock A and 29.2% from Flock B died. There were no sick lambs presented by Farmer C. In the second year, sick lambs were observed but the objectivity of the study was considered to have decreased from the first year. Evidence of this came from the inter-observer bias between farmers. There was a significant difference in the proportion of sick lambs presented by Farmers A and B but there was no significant difference in the proportion of lambs which subsequently died (1.6% and 1.8 %) of lambs born in Cohorts A and B, respectively) and which had been presented for treatment, suggesting that Farmer A selected less severely sick lambs than Farmer B.  相似文献   

Pest and disease control on intensive apple trees by overhead mobile spraying     

Barry K. Cooke  Pamela J. Herrington  Kenneth G. Jones  Norman G. Morgan 《Pest management science》1975,6(6):571-579

In 3 year field experiments on pest and disease control by mobile overhead spraying of intensive Cox's Orange Pippin apple trees, overhead booms applying 1125 litres/ha and overhead mist-blowing equipment applying 562 litres/ha, each spraying two complete rows from one alley in half the normal time, were compared with conventional automatic mast spraying at 2250 litres/ha and with conventional mist-blowing at 562 litres/ha. The overhead boom application of demeton-S-methyl (0.0036% a.i.) with azinphos-methyl (0.0165% a.i.) or of fenitrothion (0.031% a.i.) at the green cluster stage gave control of the applegrass aphid, Rhopalosiphum insertum, virtually equal to that obtained by conventional application of the same insecticides. Similarly, the overhead mist applications of conventional quantities of insecticides gave equal control, but not when applying one-quarter of the normal amount of insecticides. The conventional methods generally gave better control of apple sucker, Psylla mali. In 1971, when the incidence of apple scab, Venturia inaequalis, was only moderate, the overhead boom method gave equal control to conventional spraying with both dodine/captan (0.03% a.i. and 0.094% a.i.) and benomyl (0.025% a.i.) programmes: in 1972 and 1973, when the scab incidence was heavier, the overhead boom spraying was again equal to the conventional method with the benomyl programme but was less effective with the dodine/captan programme. The overhead mist applications gave control only when the scab incidence was light. Repeated applications of dinocap emulsion (0.025% a.i.), included in the fungicide programme in 1971, gave as good control of the active stages of fruit tree red spider mite, Panonychus ulmi, when applied by the overhead methods as by conventional spraying, but application of the benomyl programme gave poor control. Mobile overhead spraying of small intensive apple trees is a promising method but needs further development before becoming fully acceptable.  相似文献   

Thiaminase type 1-producing bacilli and ovine polioencephalomalacia     

K T Morgan  G H Lawson 《The Veterinary record》1974,95(16):361-363

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