Isolation of avian influenza virus (subtype H5N2) from chicken eggs during a natural outbreak     

D T Cappucci  D C Johnson  M Brugh  T M Smith  C F Jackson  J E Pearson  D A Senne 《Avian diseases》1985,29(4):1195-1200

Avian influenza virus (A/Chicken/Pennsylvania/83; H5N2) was recovered from the yolk, albumen, and shell surface of eggs obtained from naturally infected chicken flocks in Pennsylvania and Virginia. These findings represent the first reported isolation of avian influenza virus from the internal contents of eggs from naturally infected flocks. The need for adequate safeguards to prevent spread of the virus during commercial movement of table and hatching eggs, cracked and "checked" eggs, and egg flats and other materials is emphasized.  相似文献   

Comparison of the indirect enzyme-linked immunosorbent assay (ELISA) with the complement fixation test (CFT) for the serodiagnosis of bovine brucellosis     

Hobbs IF 《New Zealand veterinary journal》1985,33(7):112-116

Complement fixation and ELISA tests were carried out on 8772 bovine sera. Results showed that ELISA titres were, on average, approximately sixteen times higher than the corresponding C.F. titres. The specificity of ELISA appeared comparable to that of the C.F.T. There was no evidence to show that the ELISA could detect infection earlier than the C.F.T.  相似文献   

The effect of gastro-intestinal parasitism on the temporary dentition of lambs     

Orr MB  Mason P  Crosbie SF 《New Zealand veterinary journal》1985,33(4):48-52

The temporary dentitions of 18 to 39-week-old lambs with a very light or a very heavy parasite burden are compared. The heavily parasitised lambs developed longer temporary incisors which tended to protrude further forward in relation to the upper dental pad. They showed absolute hypocalcaemia and hypoalbuminaemia and relative hypophosphataemia and hypoproteinaemia and in the alveolar bone of the mandible there was a reduction in ash and matrix densities and matrix mineralisation. The incisor protrusion and lengthening may have been a consequence of the loss of supporting bone, but inappetance was likely to have been a factor contributing to the lengthening.  相似文献   

Leptospira interrogans serovar hardjo Infection in Cattle in the South Okanagan District of British Columbia   总被引：6，自引：4，他引：2       下载免费PDF全文

Kingscote BF 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(10):328-332

An outbreak of leptospirosis due to Leptospira interrogans serovar hardjo in the South Okanagan District of British Columbia was investigated. The infection was associated primarily with bulls, but serovar hardjo was isolated from both bulls and cows at slaughter. Kidney and cerebrospinal fluid were found to contain leptospires, independently of the presence and level of serum agglutinins. Treatment of a bull twice in six months with dihydrostreptomycin failed to diminish an agglutinin titer (1/200) which persisted for two years without reexposure of the bull. A serological survey of cull cows sold through a central auction mart revealed the presence of hardjo agglutinins in 15.4% of 1300 sera representing 163 herds in 20 locations. Thirty percent of these herds contained reactor cattle. The number of premises from which reactor cattle came in a given locality varied from 4% to 67.7%. Measures to control leptospirosis in the study are suggested.  相似文献   

Shell strength of eggs from medium‐bodied hybrid hens housed in cages or on range in outside pens     

B. O. Hughes  P. Dun  C. C. McCorquodale 《British poultry science》1985,26(1):129-136

1. On average, over the laying year, a higher proportion of eggs were cracked from cages (4.6%) than from range (2.0%); the difference tended to increase as the flocks aged.

2. There was evidence that eggs from range had stronger shells: they required more energy to crack, shell thickness was greater and shell deformation at 70 weeks was less (though the difference was not significant).

3. The differences between systems in shell strength, although real, were small. It is probable that environmental insults make a much larger contribution than shell strength to differences in crack incidence.

4. Eggs laid by hens on range were larger (+ 6.8% at 36 weeks and + 2.9% at 70 weeks) than those laid by the same stock housed in cages.  相似文献   

Behaviour of roaster chickens towards an automatic weighing perch     

Ruth C. Newberry  J. R. Hunt  E. E. Gardiner 《British poultry science》1985,26(2):229-237

1. Automatic weighing equipment was tested on a flock of 752 roaster chickens reared on litter to 10 weeks of age.

2. Mean body weights obtained automatically were lower than those obtained manually, mainly because of birds perching on the automatic weighing perch with part of their body in contact with the floor.

3. Birds observed on the weighing perch on one day of the week were 3–5 times more likely to use the perch again on the following 2 d than expected on the basis of random perch use by flock members. These birds were also more likely to be seen in the area immediately surrounding the perch than in similar areas elsewhere in the pen.  相似文献   

Model calculations for the optimal planning of beef performance tests using a german dual-purpose cattle population as an example     

H.-U. Graser  E. Niebel  D. Fewson 《Livestock Production Science》1985,13(3):229-250

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Productivity and fruit quality of apple in single-row and full-field planting systems     

S.J. Wertheim 《Scientia Horticulturae》1985,26(3):191-208

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Central and local actions of opioids upon reticulo-ruminal motility in sheep     

C. L. Maas  B. F. Leek 《Veterinary research communications》1985,9(1):89-113

The effects of opioids and naloxone on cyclical forestomach motility were determined in anaesthetized and conscious sheep. To assess central or peripheral opioid actions, differential routes of administration were used. Possible dynamic effects along the innervating vagovagal reflex arc were investigated electrophysiologically at the cervical level of the vagus nerve. Further, direct influences on the smooth muscle were evaluatedin vitro on isolated longitudinal reticular strips. Additionally, the effects of some spasmogenic agents were studied for comparative purposes. In anaesthetized sheep, opioids depressed in an identical manner both the amplitude of spontaneous cyclical contractions and contractions evoked by electrical stimulation of the distal end of the cut cervical vagus. In conscious sheep, low doses of normorphine and loperamide inhibited frequency and amplitude centrally (20 g/kg and 4 g/kg via carotid artery respectively), whereas locally higher dose levels (200 g/kg and 10 g/kg via coeliac artery respectively) affected only the amplitude of cyclical contractions. Furthermore the opioid peptides Leu-, Met-enkephalin and [D-Ala²-Met⁵]-enkephalinamide preferentially depressed the amplitude of cyclical motility most efficiently if administrated via the coeliac artery. These results indicate the presence both of a central opioid action depressing frequency and amplitude and of a local opioid action depressing only the amplitude of cyclical reticulo-ruminal motility. Opioids did not alter the resting discharge of afferent tension units and similarly failed to modulate tone of reticular stripsin vitro, suggesting that the opioids act locally on the intramural neuronal plexus, possibly by diminishing the output of excitatory transmitter. Whether substance P could play a role as a vagal excitatory transmitter besides the classically implicated acetylcholine has been discussed. The central opioid mechanism is probably not situated within the gastric centres but elsewhere in the brain. Naloxone ( 100 g/kg, jugular vein) stimulated the frequency of cyclical ruminal motility only in well-defined experimental conditions, probably via a central mechanism.  相似文献   

A vesicular dermatitis affecting pig snouts. An important differential diagnosis for infectious vesicular diseases     

Montgomery JF  Oliver RE 《New Zealand veterinary journal》1985,33(6):98

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