In a series of feeding trials with veal calves, the effect of dietary Cu levels on the Cu concentration in calf livers was investigated. The examined rations contained per kg of dry matter (DM) 2, 6, 8, 10 and 30 mg of Cu. The copper was added as sulfate. Up to a live weight of 100 kg, the ration was composed of whole milk upgraded with minerals and vitamins. This ration was supplemented with a milk replacer once the calves had reached 100 kg. In addition to the feeding trials, 40 calf livers were bought from several slaughter houses across Switzerland and the corresponding Cu contents were analysed. With a dietary Cu level of 2, 6, 8, 10 and 30 mg per kg of DM, the average Cu concentrations of the corresponding livers were 52 ± 17 mg, 97 ± 18 mg, 170 ± 19 mg, 178 ± 35 mg and 389 ± 108 mg on a fresh matter basis. The coefficient of variation varied between around 10 % and 35 % for a comparable Cu supply. There exists a close relationship between the dietary and hepatic Cu concentration (R2 = 0.804). The Cu content of the slaughter house livers averaged 63 ± 79 mg per kg of FM. Only 5 % of the liver samples surpassed 250 mg Cu per kg of FM. These 250 mg Cu per kg of FM is the concentration which is under discussion as a possible threshold value for the animals and food hygiene reasons.
Stable climate has an important impact on the respiratory health of horses. In a study on indoor climate quality, three different ventilation systems were tested.
Although milk-production oriented (MPO) cow breeds have also become established in the mountain region, farms with the dual-purpose ‘Original Simmental’ breed are proving to be economically viable, with lower costs and higher direct payments making up for lower revenues from milk.
High milk yields before drying-off increase the risk of udder infections during the dry period. An online survey highlights what drying-off methods are currently used and how farmers rate the ‘incomplete milking’ approach for reducing milk yield.