Prevalence of leukosis antibodies in relation to cattle's age]     

E Forschner  P Ewald  M V Keyserlingk  W R?ttgen  M J Seidler 《Berliner und Münchener tier?rztliche Wochenschrift》1979,92(1):3-5

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Key Factors Affecting Reproductive Success of Thoroughbred Mares and Stallions on a Commercial Stud Farm          下载免费PDF全文

EA Lane  MLJ Bijnen  M Osborne  SJ More  ISF Henderson  P Duffy  MA Crowe 《Reproduction in domestic animals》2016,51(2):181-187

To evaluate factors contributing to fertility of thoroughbred mares, data from 3743 oestrous periods of 2385 mares were collected on a large thoroughbred farm in Ireland. Fourteen stallions (mean age 8.3 years; range 4–15 years) had bred 2385 mares (mean age 9.4 years; range 3–24 years). Maiden mares accounted for 12%, mares with a foal at foot for 64%, and barren, slipped or rested mares for 24% of the total. The mean pregnancy rate per cycle was 67.8% (68.6% in year 1 and 66.9% in year 2). Backward stepwise multivariable logistic regression analysis was utilized to develop two models to evaluate mare factors, including mare age, reproductive status, month of foaling, dystocia, month of cover, foal heat, cycle number, treatments, walk‐in status and stallion factors including stallion identity, stallion age, shuttle status, time elapsed between covers and high stallion usage on the per cycle pregnancy rate and pregnancy loss. Old age (p < 0.001) and cover within 20 days post‐partum (p < 0.003) were associated with lowered pregnancy rates. High mare age (p < 0.05) and barren, slipped or rested reproductive status (p = 0.05) increased the likelihood of pregnancy loss. Uterine inflammation or infection, if appropriately treated, did not affect fertility. Only high usage of stallions (used more than 21 times in previous week) was associated with lowered (p = 0.009) pregnancy rates. However, shuttle stallions were more likely to have increased (p = 0.035) pregnancy survival, perhaps reflecting a bias in stallion selection. In conclusion, mare age exerted the greatest influence on fertility; nonetheless, thoroughbreds can be effectively managed to achieve high reproductive performance in a commercial setting.  相似文献   

Pathogenesis of infectious bronchitis virus in vaccinated chickens of two different major histocompatibility B complex genotypes     

Joiner KS  Hoerr FJ  Ewald SJ  van Santen VL  Wright JC  van Ginkel FW  Toro H 《Avian diseases》2007,51(3):758-763

Infectious bronchitis (IB) disease progression in vaccinated chickens after challenge was evaluated in a single commercial line of layer chickens presenting two different major histocompatibility complex (MHC) B complex genotypes. MHC B genotypes were determined by DNA sequence-based typing of BF2 alleles. In total, 33 B2/B15 and 47 B2/B21 chickens were vaccinated with an Ark-type IB virus (IBV) attenuated vaccine and challenged with Ark-type IBV field isolate AL/4614/98 14 days later. Additional chickens of both genotypes served as unvaccinated/challenged and unvaccinated/nonchallenged controls. Clinical signs, histopathologic analysis, detection of IBV genomes in tears, and IBV-specific immunoglobulin A (IgA) in tears were used to evaluate disease progression and immune response. The incidence of IBV respiratory signs was significantly higher in B2/21 than in B2/B15 MHC genotype birds. However, neither the severity and duration of respiratory signs nor the severity and incidence of histologic lesions differed significantly with MHC genotype. The levels of IBV-specific IgA in tears of vaccinated and challenged chickens did not differ significantly between MHC genotypes. IBV genomes were present in the tears of vaccinated and challenged birds, and the incidence of detectable IBV genomes did not vary significantly with MHC B genotype. From an applied perspective, these results indicate that vaccinated commercial outbred chickens with these MHC genotypes are equally resistant to IBV.  相似文献   

The effects of vaccination of Merino ewes with an attenuated Australian bluetongue virus serotype 23 at different stages of gestation   总被引：1，自引：0，他引：1  

M. FLANAGAN  SJ JOHNSON 《Australian veterinary journal》1995,72(12):455-457

SUMMARY A cell culture attenuated Australian bluetongue virus serotype 23 (BLU23) prototype vaccine was assessed for its effects on pregnant Merino sheep. Seventy-six ewes were vaccinated at 5 different stages of gestation, and the failure to lamb at term was as follows: 35 to 43 days of gestation, 20/36 (56%); 57 to 64 days of gestation, 3/10 (30%); 81 to 88 days of gestation, 3/10 (30%); 109 to 116 days of gestation, 0/10 (0%); 130 to 137 days of gestation, 0/10 (0%). Of 30 ewes vaccinated with a cell culture supernatant fluid control between 35 and 43 days of gestation, 6.7% (2/30) failed to lamb at term. Two ewes vaccinated with BLU23 vaccine between 35 and 43 days of gestation had lambs with hydranencephaly. All other lambs born were clinically normal. Three ewes vaccinated with BLU23 aborted. Two of these were vaccinated between 35 and 43 days of gestation, the 3rd between 81 and 88 days of gestation. Five lambs were born with BLU group antibody. Four of these were from ewes vaccinated between 35 and 43 days of gestation, and 2 of these had hydranencephaly. The fifth was from a ewe vaccinated between 57 and 64 days of gestation. The vaccine did not produce disease in adult sheep, but was a potent cause of early foetal death and to a much lesser extent foetal malformation.  相似文献   

Gram-negative Mastitis in Early Lactation May Interfere with Ovarian and Certain Endocrine Functions and Metabolism in Dairy Cows   总被引：1，自引：0，他引：1  

G Huszenicza  S Jánosi  M Kulcsár  P Kóródi  SJ Dieleman  J Bartyik  P Rudas  P Ribiczei-Szabó 《Reproduction in domestic animals》1998,33(3-4):147-153

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Allgemeine Bemerkungen zur Durchführung ernährungsbiologischer Untersuchungen     

Ewald Frömming 《Journal of pest science》1955,28(1):7-9

Ohne Zusammenfassung  相似文献   

Comparison of three commercial rapid agglutination test kits for identification of coagulase positive staphylococci from foods and animals.     

I J Holme  O Rosef  S Ewald 《Acta veterinaria Scandinavica》1991,32(2):155-161

Three rapid agglutination assays for the identification of Staphylococcus aureus Monostaph (Bionor A/S, Skien, Norway), Staphyslide-Test (BioMerieux, Lyon, France) and Staph-Rapid-Test (Roche, Basel, Switzerland), were compared. A total of 104 Gram-positive, catalase positive cocci were tested: Nineteen Staphylococcus reference strains comprising 15 spp. (4 strains were coagulase positive), and 7 Micrococcus reference strains comprising 4 spp.; 22 food isolates comprising 13 S. aureus, 8 coagulase positive Staphylococcus spp., and 1 Micrococcus sp.; 56 animal isolates comprising 11 S. aureus, 9 S. hyicus subsp. hyicus, 2 S. intermedius, 15 coagulase positive and 19 coagulase negative Staphylococcus spp. Totally 54 strains were coagulase positive. Considering agglutination of a coagulase positive strain as a correct identification, Monostaph, Staph-Rapid-Test, and Staphyslide-Test correctly identified 52 (96.3%), 47 (87.0%) and 48 (89.0%) of the coagulase positive staphylococci, respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test showed 1 (2.0%), 4 (8.0%) and 4 (8.0%) false positive reactions respectively. Monostaph, Staph-Rapid-Test and Staphyslide-Test gave 0 (0.0%), 6 (5.8%) and 7 (6.7%) non-interpretable reactions, respectively. Monostaph may be a good alternative to the tube-coagulase test for rapid and reliable identification of coagulase positive staphylococci from both food and veterinary sources. However, false negative reactions may occur with coagulase positive strains of S. hyicus subsp. hyicus and S. intermedius.  相似文献   

Mycotoxins as a risk factor for the origin of diseases and production decreases in swine facilities--an epidemiologic study]     

C Ewald  A Rehm  C Haupt 《Berliner und Münchener tier?rztliche Wochenschrift》1991,104(5):161-166

Feed samples checked for the mycotoxins zearalenone and ochratoxin A from the harvest 1987 were positive at a markedly higher percentage (37.5%) compared to previous years, which is explained by the especially unfavourable harvesting conditions of 1987. In certain herd problems affecting the digestive or respiratory tract, mycotoxins could be detected with a much higher frequency (64.7% and 50.0% respectively). The mean level detected in feed samples by thin layer chromatography ranged within 30.3 ppb for zearalenone and within 58.3 ppb for ochratoxin A. In most cases there was a history of infertility. Considering the clinical situation, which is presented comparatively in herds with positive mycotoxin results, the possible involvement of mycotoxins in the disease, even at very low concentrations, is pointed out. In this context, zearalenone is incriminated of being an indicator of a multitoxic process besides its own direct effects. According to own experiences low levels of zearalenone in the range of 20-50 ppb in the feed have to be considered hazardous. If changing of pig feed in cases of herd problems will be recommended, a level of less than 10 ppb of zearalenone, especially in sow and piglet rations, should not be exceeded. Same may be valid to ochratoxin A.  相似文献   

Japanese supercomputer technology     

Buzbee BL  Ewald RH  Worlton WJ 《Science (New York, N.Y.)》1982,218(4578):1189-1193

Under the auspices of the Ministry for International Trade and Industry the Japanese have launched a National Superspeed Computer Project intended to produce high-performance computers for scientific computation and a Fifth-Generation Computer Project intended to incorporate and exploit concepts of artificial intelligence. If these projects are successful, which appears likely, advanced economic and military research in the United States may become dependent on access to supercomputers of foreign manufacture.  相似文献   

Imaging of intermittency in ripple-wave turbulence     

WB Wright  R Budakian  DJ Pine  SJ Putterman 《Science (New York, N.Y.)》1997,278(5343):1609-1612

The dynamics of a fluid surface filled with high-amplitude ripples were studied with a technique (diffusing light photography) that resolves the height at all locations instantaneously. Even when nonlinearities are strong enough to generate a (Kolmogorov) cascade from long wavelength (where energy is input) to shorter wavelength, the resulting turbulent state contains large coherent spatial structures. The appearance of these structures in a thermal equilibrium state (with the same average energy) would be highly improbable.  相似文献