| The existing methods of predicting the occurrence of hypocalcemia for individual animals are limited, usually alkaline phosphatase (AP) activity prior to calving is used. At the herd level, urinary net acid-base excretion (NABE) is a suitable risk assessment parameter. Other modern laboratory diagnostic parameters, describing bone metabolic activity have not been established to date. However, prediction of the onset of hypocalcemia would be of great benefit for animal health and performance of calving cows. One of the early signs of hypocalcemia is a decrease in rumen motility. However, diseases such as rumen acidosis or traumatic reticuloperitonitis, peritonitis, abomasal ulcers, general febrile diseases, and systemic inflammatory reactions result likewise in decreased reticulorumen motility, but this is caused by other pathogenetic mechanisms (e.g., endotoxins, endogenous mediators, nervous control). Therefore, we hypothesize that the changes in motility that result from peripartal hypocalcemia follow typical patterns and thus can be identified and used for early diagnosis. Due to recent technical developements in livestock production (Precision Livestock Farming), boli for the detection of the reticuloruminal motility are available. Thereby, the reticuloruminal motility can be recorded, transmitted to an external storage devise and evaluated over an extended period of time.
Early detection of hypocalcemia would allow interventions by farmers and veterinarians to treat subclinical hypocalcemia early and preventing clinical disease. In addition, measurement of motility would allow assessment of the effectiveness of prophylactic and diagnostic measures. Furthermore, it seems reasonable that the algorithms to be developed could also be used for improved prediction of the time of birth. |