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  • Author or Editor: Michael L. Pennell x
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Abstract

Objective—To evaluate the sensitivity of 4 commercially available microchip scanners used to detect or read encrypted and unencrypted 125-, 128-, and 134.2-kHz microchips under field conditions following implantation in dogs and cats at 6 animal shelters.

Design—Cross-sectional study.

Animals—3,949 dogs and cats at 6 animal shelters.

Procedures—Each shelter was asked to enroll 657 to 660 animals and to implant microchips in 438 to 440 animals (each shelter used a different microchip brand). Animals were then scanned with 3 or 4 commercial scanners to determine whether microchips could be detected. Scanner sensitivity was calculated as the percentage of animals with a microchip in which the microchip was detected.

Results—None of the scanners examined had 100% sensitivity for any of the microchip brands. In addition, there were clear differences among scanners in regard to sensitivity. The 3 universal scanners capable of reading or detecting 128- and 134.2-kHz microchips all had sensitivities ≥ 94.8% for microchips of these frequencies. Three of the 4 scanners had sensitivities ≥ 88.2% for 125-kHz microchips, but sensitivity of one of the universal scanners for microchips of this frequency was lower (66.4% to 75.0%).

Conclusions and Clinical Relevance—Results indicated that some currently available universal scanners have high sensitivity to microchips of the frequencies commonly used in the United States, although none of the scanners had 100% sensitivity. To maximize microchip detection, proper scanning technique should be used and animals should be scanned more than once. Microchipping should remain a component of a more comprehensive pet identification program.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate in vitro biological activity of gemcitabine, alone and in combination with Pamidronate or carboplatin, against canine osteosarcoma (OSA) cell lines.

Sample Population—In vitro cultures of OSA cell lines OSA8, OSA16, OSA32, and OSA36.

Procedures—Cell lines were treated with gemcitabine alone or in combination with pamidronate or carboplatin. Cell viability was assessed with the water soluble tetrazolium-1 (WST-1) assay, cell cycle distribution was evaluated by means of propidium iodide staining, and apoptosis was assessed by measuring caspase-3/7 activity. Synergy was quantified by use of combination index (CI) analysis.

Results—For all of the cell lines, treatment with gemcitabine induced growth inhibition, cell cycle arrest, and apoptosis. No synergistic or additive activity was identified when OSA cell lines were treated with gemcitabine in combination with pamidronate. However, when OSA cell lines were treated with gemcitabine in combination with carboplatin, a significant decrease in cell viability was observed, compared with treatment with carboplatin alone, and the drug combination was determined to be synergistic on the basis of results of CI analysis. For 3 of the 4 cell lines, this activity was greater when cells were treated with carboplatin prior to gemcitabine rather than with gemcitabine prior to carboplatin.

Conclusions and Clinical Relevance—Gemcitabine exhibited biological activity against canine OSA cell lines in vitro, and a combination of gemcitabine and carboplatin exhibited synergistic activity at biologically relevant concentrations. Findings support future clinical trials of gemcitabine alone or in combination with carboplatin for the treatment of dogs with OSA.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate sensitivity of 4 commercially available microchip scanners used to detect or read encrypted and unencrypted 125-, 128-, and 134.2-kHz microchips under controlled conditions.

Design—Evaluation study.

Sample Population—Microchip scanners from 4 manufacturers and 6 brands of microchips (10 microchips/brand).

Procedures—Each microchip was scanned 72 times with each scanner passed parallel to the long axis of the microchip and 72 times with each scanner passed perpendicular to the long axis of the microchip. For each scan, up to 3 passes were allowed for the scanner to read or detect the microchip. Microchip and scanner order were randomized. Sensitivity was calculated as the mean percentage of the 72 scans for each microchip that were successful (ie, the microchip was detected or read).

Results—None of the scanners had 100% sensitivity for all microchips and both scanning orientations, and there were clear differences between scanners on the basis of operating frequency of the microchip, orientation of the microchip, and number of passes used to detect or read the microchip. For the 3 scanners designed to detect or read microchips of all 3 frequencies currently used in the United States, sensitivity was highest for 134.2-kHz microchips and lower for 125- and 128-kHz microchips. None of the scanners performed as well when only a single pass of the scanner was used to detect or read the microchips.

Conclusions and Clinical Relevance—Results indicated that use of multiple passes in different directions was important for maximizing sensitivity of microchip scanners.

Full access
in Journal of the American Veterinary Medical Association