Ascorbic acid, better known as Vitamin C, is being ingested mainly through forage and nutritional supplements. Most of it is excreted unaltered in the urine again. For this reason a high percentage of the animals shows a clearly increased Ascorbic acid level in the urine. This results in lowered or even false negative results of the blood and glucose pads with many urine test strips on the market. Therefore diagnostic or therapeutic actions may be taken too late. Analyticons’ CombiScreen® PLUS test strip offers a considerable higher reliability due to its integrated ascorbic acid protection system.