[Use of serum haptoglobin concentration as an indicator in animal health monitoring of dairy cows].

Objective: To investigate the association between haptoglobin concentration in the blood and the occurrence of ketosis, selected clinical parameters as well as lameness in dairy cows.

Material And Methods: The data was collected on 39 dairy farms in Bavaria over a period of 8 months. In 712 Simmental and Brown Swiss cows, clinical examinations as well as milk and blood samplings were performed between 10 and 30 days after calving.

Influence of various amounts of fumaric acid on performance and parameters of the acid-base balance of growing bulls fed with grass or maize silage.

The aim of the present study was to determine the effects of the potential methane reducer fumaric acid on the fattening performance and acid-base balance of growing bulls fed two different silage types as roughage (maize and grass silage). A total of 62 fattening bulls (German Holstein breed, initial body weight: 266 +/- 42 kg), randomly assigned to eight feeding groups, received four levels of fumaric acid (0, 100, 200 or 300 g/d) at each silage type. The daily feed and water intake and the live weight were measured over the whole testing period of 280 days.