20.500.12556/RUL-132782 Minimal erythema dose determination in Holstein Friesian cattle Cattle on pasture are continuously exposed to solar UV radiation, which has been associated with biological effects such as sunburn, photosensitization, squamous cell carcinoma, and cutaneous vitamin D$_3$ production. The minimal erythema dose (MED) required to produce first-degree sunburn (erythema) is poorly researched in cattle. Since cattle are naturally covered with dense hair coats, the MED is influenced by the UV protection offered by the hair. The objective of this study was to determine the MED on intact-hair-covered (MED-H) and shaved white skin (MED-S) of Holstein Friesian cattle. Twenty-one Holstein Friesian cows and heifers were MED tested using a narrowband UV-B LED light (peak irradiance at 292 nm) on eight hair-covered and eight shaved areas over white skin previously unexposed to direct sunlight. Erythema was visually assessed after 24 h. The mean MED-H and MED-S were 5,595 and 329 J/m$^2$, respectively. Heifers had a higher MED-H compared to cows, 7,600 and 4,969 J/m$^2$, respectively. The mean UV transmittance of white cattle hair was 6.7%. MED-H was correlated with hair length (Spearman’s rho = 0.76). A linear regression model showed that each millimeter of hair coat length increased the MED-H by 316 J/m$^2$. In conclusion, this study provides a MED testing protocol for cattle and reports standardized values of MED for cattle on intact-hair-covered and shaved areas. cow ultraviolet rays sunburn phototesting hair coat cattle diseases cattle true false true Angleški jezik Ni določen Članek v reviji 2021-11-03 10:10:01 2021-11-03 10:10:01 2023-05-13 03:36:48 0000-00-00 00:00:00 2021 0 0 7 str. art. 757452 Vol. 8 2021 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 636.2.09:616 2297-1769 10.3389/fvets.2021.757452 83093763 RAZ_Hodnik_Jaka_Jakob_2021.pdf RAZ_Hodnik_Jaka_Jakob_2021.pdf 1 6B6A05CDB6DCEE1A8F574FA63F0CC7E2 327295371d032308aa6c0eee14d602c6a867d8bbff7a6de75d15459694199919 a4689e30-3c89-11ec-abdb-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=150487 https://www.frontiersin.org/articles/10.3389/fvets.2021.757452/full 1 c905f1ee-3c85-11ec-abdb-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=150482 Veterinarska fakulteta Fakulteta za elektrotehniko 0 0 0