RESUMO
The objective was to validate the efficacy of Moocall® comparing it to a routine clinical examination. Altogether 38 Holstein cows were enrolled in this study (Moocall® group: 16 heifers and 8 cows; control group: 9 heifers and 5 cows). Clinical examinations were performed every 6 h over the 7 days period before the predicted calving date. The examined traits were changes in pelvic ligament relaxation, edema of the vulva, teat filling, vaginal secretion, tail tip flexibility, tail raising and behavior. There were no significant differences in Moocall® alerts between heifers and cows. The time lag between the first warning of Moocall® and the onset of labor was 21.2 ± 20.2 h (max: 95.4 h; min: 0.1 h; p = 0.87) for heifers and 29.6 ± 29.6 h (max: 177.8 h; min: 0 h; p = 0.97) for cows. Linear models including Moocall® alerts showed a significantly better fit to the time until calving than models without Moocall® information (without variable selection: p = 0.030, with variable selection: p < 0.01). In the best-fitting model, class 2 alerts (enhanced tail activity over 2 h) contributed with a higher significance (p < 0.01). Vice versa, models including additional traits were outperformed the use of Moocall® alerts alone. In the best fitting model, class 2 alerts (enhanced tail activity during 2 h) contributed with a higher significance (p < 0.01) than any of the best clinical predictive parameters, such as pelvic ligament relaxation (p = 0.01), tail tip flexibility (p = 0.01) or behavior (p = 0.01).
RESUMO
The application of botulinum neurotoxins (BoNTs) for medical treatments necessitates a potency quantification of these lethal bacterial toxins, resulting in the use of a large number of test animals. Available alternative methods are limited in their relevance, as they are based on rodent cells or neuroblastoma cell lines or applicable for single toxin serotypes only. Here, human motor neurons (MNs), which are the physiological target of BoNTs, were generated from induced pluripotent stem cells (iPSCs) and compared to the neuroblastoma cell line SiMa, which is often used in cell-based assays for BoNT potency determination. In comparison with the mouse bioassay, human MNs exhibit a superior sensitivity to the BoNT serotypes A1 and B1 at levels that are reflective of human sensitivity. SiMa cells were able to detect BoNT/A1, but with much lower sensitivity than human MNs and appear unsuitable to detect any BoNT/B1 activity. The MNs used for these experiments were generated according to three differentiation protocols, which resulted in distinct sensitivity levels. Molecular parameters such as receptor protein concentration and electrical activity of the MNs were analyzed, but are not predictive for BoNT sensitivity. These results show that human MNs from several sources should be considered in BoNT testing and that human MNs are a physiologically relevant model, which could be used to optimize current BoNT potency testing.
