Circulating Metabolic Hormones During the Peripubertal Period and Their Association with Testicular Development in Bulls     

LFC Brito  AD Barth  NC Rawlings  RE Wilde  DH Crews Jr    PS Mir  JP Kastelic 《Reproduction in domestic animals》2007,42(5):502-508

The objective of the present study was to characterize changes in serum metabolic hormones concentrations from 20 weeks before to 20 weeks post-puberty in bulls and to investigate the associations of metabolic hormones concentrations with testicular development. Leptin concentrations increased from 16 weeks before puberty to 8 weeks post-puberty and insulin concentrations increased from puberty to 8 weeks post-puberty. Growth hormone concentrations decreased after 4 weeks post-puberty, whereas IGF-I concentrations increased from 8 weeks before puberty to 8 weeks post-puberty. During this period, testicular growth was accelerated and testosterone secretion increased substantially, without any significant changes in gonadotropin secretion. Monthly circulating concentrations of leptin, IGF-I and insulin accounted for 63% of the variation in scrotal circumference and 59% of the variation in paired testes volume. In conclusion, the secretion of metabolic hormones was not associated with changes in gonadotropins concentrations. Furthermore, the associations of leptin, IGF-I and insulin concentrations with testes size indicated that these hormones might be involved in a gonadotropin-independent mechanism regulating the testicular development in peripubertal bulls.  相似文献   

Experimental infection of six-month-old sheep with Escherichia coli O157:H7     

Wales AD  Clifton-Hadley FA  Cookson AL  Dibb-Fuller MP  La Ragione RM  Sprigings KA  Pearson GR  Woodward MJ 《The Veterinary record》2001,148(20):630-631

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High-power directional emission from microlasers with chaotic resonators     

C Gmachl  F Capasso  EE Narimanov  JU Nockel  AD Stone  J Faist  DL Sivco  AY Cho 《Science (New York, N.Y.)》1998,280(5369):1556-1564

High-power and highly directional semiconductor microcylinder lasers based on an optical resonator with deformed cross section are reported. In the favorable directions of the far-field, a power increase of up to three orders of magnitude over the conventional circularly symmetric lasers was obtained. A "bow-tie"-shaped resonance is responsible for the improved performance of the lasers in the higher range of deformations, in contrast to "whispering-gallery"-type modes of circular and weakly deformed lasers. This resonator design, although demonstrated here in midinfrared quantum-cascade lasers, should be applicable to any laser based on semiconductors or other high-refractive index materials.  相似文献   

Alkoxy derivatives of dyrene. Identification and carboxylesterase inhibition     

C E Mendoza  P J Wales  G V Hatina 《Journal of agricultural and food chemistry》1971,19(1):41-45

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Salmonellas from the cane toad, Bufo marinus     

P O'SHEA  R SPEARE  AD THOMAS 《Australian veterinary journal》1990,67(8):310-310

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Restriction-endonuclease analysis of Australian isolates of Leptospira interrogans serovar hardjo from cattle with agalactia and abortion   总被引：1，自引：0，他引：1  

S. DJORDJEVIC  M. HORNITZKY  AD ROSS  RJ WHITTINGTON 《Australian veterinary journal》1993,70(3):98-100

SUMMARY Polyacrylamide gel electrophoresis and agarose gel electrophoresis were used to resolve restriction endonuclease digests of 20 Australian isolates of Leptospira interrogans cultured from urine samples of cattle with agalactia and abortion. The restriction endonuclease profiles of 19 isolates closely matched the profiles of L interrogans serovar hardjo subtype hardjobovis reference strains. The remaining isolate had a different restriction profile from subtype hardjobovis and subtype hardjoprajitno reference strains and was serologically identified as serovar pomona. Silver staining of polyacrylamide gels gave enhanced resolution of restriction fragments compared with the traditional method of ethidium bromide staining of agarose gels.  相似文献   

Reply     

AD RIJNBERK 《Australian veterinary journal》1997,75(10):760-760

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Uptake of drugs from topically applied anti-inflammatory preparations applied to racing animals     

AD THOMAS  IC BOWATER  JH VINE  JG McLEAN 《Australian veterinary journal》1997,75(12):897-901

Objective To determine whether a drug detected in the blood or urine of a racing animal could have penetrated through the skin from a topically applied preparation.
Design Blood and urine of dogs and horses were analysed after topical administration of three common nonsteroidal anti-inflammatory preparations.
Experimental method Dimethylsulphoxide was analysed using a gas chromatograph with a flame photometric detector. Phenylbutazone, its metabolites and lignocaine were analysed using a gas chromatograph with a mass selective detector.
Results Dimethylsulphoxide, phenylbutazone and ligno-caine were detected in dog urine after muliple applications of the preparations. The maximum concentration of dimethyl-sulphoxide in dog urine correlated with the concentration of dimethylsulphoxide in the preparation. Phenylbutazone penetrated the skin more effectively from the cream than from the solution or gel preparations. This penetration was independent of the concentration of dimethylsulphoxide.
Conclusion The superior penetration of phenylbutazone from the cream can be explained by it being present as a neutral molecule in an hydrophobic medium. It is proposed that phenylbutazone penetrates the skin of greyhounds most effectively by a hydrophobic lipid route which is likely to be different from the path by which dimethylsulphoxide penetrates the skin.  相似文献   

Survey of the prevalence of Salmonella species on commercial laying farms in the United Kingdom     

Snow LC  Davies RH  Christiansen KH  Carrique-Mas JJ  Wales AD  O'Connor JL  Cook AJ  Evans SJ 《The Veterinary record》2007,161(14):471-476

A survey of salmonella infection on 454 commercial layer flock holdings in the uk was carried out between October 2004 and September 2005. Fifty-four (11.7 per cent, 95 per cent confidence interval 9.3 to 14.0 per cent) were salmonella positive. The most common serovar identified was Salmonella Enteritidis at a prevalence of 5.8 per cent, and 70 per cent of these isolates were phage types 4, 6, 7 and 35. Salmonella Typhimurium was the second most prevalent serovar, found in 1.8 per cent of the farms. Of the three other serovars given top priority by the eu because of their public health significance, Salmonella Virchow and Salmonella Infantis were each isolated from one holding, but Salmonella Hadar was not isolated from any of the holdings. Analysis of antimicrobial resistance patterns revealed that over 76 per cent of the isolates were sensitive to all of the 16 drugs tested, and all the isolates were sensitive to ciprofloxacin, gentamicin, ceftazidime, apramycin, amikacin, amoxicillin/clavulanic acid, neomycin and cefotaxime.  相似文献   

Stress radiographic assessment of collateral ligament constraints on the feline tarsocrural joint     

ES Martin  T Foo  G Hosgood  AD Moles 《Australian veterinary journal》2023,101(1-2):65-77

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