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991.
J. Fraser McConnell BVM&S Laurent S. Garosi DVM 《Veterinary radiology & ultrasound》2004,45(4):327-330
Intervertebral disk extrusion is rarely reported in the cat. In this case, the clinical, radiologic, and magnetic resonance imaging findings of an acute intramedullary intervertebral disk extrusion in a 5-year-old domestic shorthaired cat are described. Radiographically, there was mineralized disk material within the vertebral canal. On magnetic resonance images, the disk material was found to be within the spinal cord. A linear disk trail extending from the disk space into the spinal cord may be specific for intramedullary disk extrusion. 相似文献
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993.
P Zhang N Fegan I Fraser P Duffy R E Bowles A Gordon P J Ketterer W Shinwari P J Blackall 《Journal of veterinary diagnostic investigation》2004,16(5):458-460
Two outbreaks of fowl cholera on a multiage free-range egg farm were investigated. The outbreaks occurred in 1994 and 2002. A total of 22 strains of Pasteurella multocida were available for study, 11 from the 1994 outbreak and 11 from the 2002 outbreak. Lesions typical of acute fowl cholera were seen in the 1994 outbreak, whereas both acute and chronic fowl cholera occurred in the 2002 outbreak. The isolates were examined in an extended phenotypic typing methodology, by a P. multocida-specific polymerase chain reaction (PCR), by the Heddleston somatic serotyping scheme, and by restriction endonuclease analysis (REA) typing using the enzyme HpaII. All 22 strains had the same phenotypic properties, all were confirmed as P. multocida by PCR, all were Heddleston serovar 4, and all had the same REA pattern. The results indicate that these 2 outbreaks were caused by the same clone of P. multocida--despite the 8-year time period between the outbreaks. 相似文献
994.
Cloning and characterization of a bovine genomic fragment homologous to epidermal growth factor genes 下载免费PDF全文
S.J. John B.F. Benkel S. Bilodeau-Goeseels 《Canadian journal of veterinary research》2004,68(4):293-301
Epidermal growth factor (EGF) is a potent mitogen for a variety of cell types. The 53-amino acid mature EGF protein is encoded by sequences in exons 20 and 21 of a gene spanning over 110 kb. In this study, we report the cloning and characterization of 7.5 kb of bovine genomic sequence homologous to exon 19 through 21 from EGF genes from other mammalian species. The cloned gene fragment had an unusual sequence composition in the form of an in-frame TGA codon in the coding sequence. The sequence was expressed at low levels in kidney tissue and the corresponding cDNA contained the TGA codon. The level of similarity between the bovine exonic sequence and the human, porcine, murine, feline, and canine corresponding sequences varied from 64% to 73%; however, when only sequences encoding the mature EGF protein were compared, the level of similarity between the bovine sequence and the sequence from these species was 59% to 66%. The sequence similarity of the deduced mature protein was lower (34% to 39%) than the sequence similarity of the deduced propeptide. Although the cloned sequences could originate from a bovine EGF pseudogene, the possibility exists that they originate from the functional EGF gene. An as yet unidentified mechanism to by-pass the stop codon would allow the synthesis of a functional EGF protein. Alternatively, the cloned sequence could originate from an EGF-like gene. 相似文献
995.
Veterinary Research Communications - 相似文献
996.
997.
998.
P. López-Romero R. Rekaya M. J. Carabaño 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2004,121(1):14-25
Test‐day milk yields from Spanish Holstein cows were analysed with two random regression models based on Legendre polynomials under two different assumptions of heterogeneity of residual variance which aim to describe the variability of temporary measurement errors along days in milk with a reduced number of parameters, such as (i) the change point identification technique with two unknown change points and (ii) using 10 arbitrary intervals of residual variance. Both implementations were based on a previous study where the trajectory of the residual variance was estimated using 30 intervals. The change point technique has been previously implemented in the analysis of the heterogeneity of the residual variance in the Spanish population, yet no comparisons with other methods have been reported so far. This study aims to compare the change point technique identification versus the use of arbitrary intervals as two possible techniques to deal with the characterization of the residual variance in random regression test‐day models. The Bayes factor and the cross‐validation predictive densities were employed for the model assessment. The two model‐selecting tools revealed a strong consistency between them. Both specifications for the residual variance were close to each other. The 10 intervals modelling showed a slightly better performance probably because the change point function overestimates the residual variance values at the very early lactation. 相似文献
999.
D. Marletta S. Bordonaro A. M. Guastella G. D'Urso 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2004,121(1):52-56
In this study we surveyed two endangered Sicilian goat breeds (Girgentana and Argentata dell'Etna) for genetic polymorphism at the CSN1S2 locus. In a total of 537 goats, we detected CSN1S2A, CSN1S2B, CSN1S2C° (CSN1S2C + CSN1S2E), CSN1S2D, CSN1S2F and CSN1S2O alleles by means of various polymerase chain reaction (PCR), allele specific‐PCR (AS–PCR) and PCR‐restriction fragment length polymorphism (RFLP) reactions with the aim of improving the knowledge of the genetic resource of these two breeds. Three and five alleles, with six and twelve genotypes, were identified at CSN1S2 locus, in Girgentana and Argentata, respectively. Argentata dell'Etna showed a higher degree of genetic variation. The allelic and genotypic distribution seems to be significantly different (p < 0.001) in the two breeds. In Argentata the rare null allele (CSN1S2O) was found at low frequency (0.033); this genetic peculiarity makes its preservation worthwhile. 相似文献
1000.
M. Szydlowski M. Stachowiak M. Mackowski M. Kamyczek R. Eckert M. Rozycki M. Switonski 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2004,121(3):149-155
Porcine leptin gene (LEP) and its association with production traits was analysed in the Polish Large White (PLW, n = 135), Polish Landrace (PL, n = 120) and synthetic line 990 (L990, n = 184). Two fragments of exon 3 of LEP were studied with the use of RFLP and SSCP techniques. The frequencies of C allele for the T3469C polymorphic site were 0.11, 0.10 and 0.11 in PLW, PL and L990, respectively. Phenotypic data were collected for the average daily weight gain, the feed conversion ratio, the weight of abdominal fat, backfat thickness (five measurements), intramuscular fat, meat content, loin weight, loin muscle area, ham weight and ham cut weight. The contrasts between TT and TC genotypes at the T3469C polymorphic site were estimated in the unitrait Animal Model with genotype at the RYR1 locus included. The lowest p values occurred for association test between T3469C polymorphism and intramuscular fat content in PLW (0.26 ± 0.14%, p = 0.05) and loin weight in L990 (?0.32 ± 0.13 kg, p = 0.01). We conclude that the detected associations are population‐specific and the analysed polymorphism of the LEP gene does not contribute directly to genetic variability of growth and carcass traits in pigs. 相似文献