In foreign beef production herds F1-crossbred cows between beef x dairy breed are common. The goal of this investigation, carried out on the ETH research stations, was to compare different production parameters of 20 F1 crossbreed cows Angus x Holstein and 22 pure-bred Angus cows. All of the 42 animals, mated with Angus, were calving to the half in fall 1999 and in spring 2000. During stable feeding time the intended energy level of the total mixed ration was 5.0 MJ NEL per kg dry matter. The last two month before slaughter the calves received a small quantity of barley. The cows and their calves passed during summertime on the ETH alpine pastures Weissenstein at 2000 m above sea level up to 2500 m. The calves were weaned and slaughtered at once as soon as they had reached a sufficient fat cover. Individual feed intake of the cows was recorded daily as long as the animals were fed indoor. Live weight of cows and calves has been measured every two weeks. After slaughter the left carcass side was dissected in meet, fat and bones. Concerning daily food energy intake in the beginning of the lactation (week 1 – 11) the pure-bred Angus cows consumed 8.1 MJ NEL more than the crossbred cows. Towards the end of the lactation (week 30 – 44) there is no difference between the two breeds. Concerning daily weight gain there exist no difference between crossbred and pure-bred calves. Whereas the pure-bred Angus calves surpass the crossbred calves in meat percentage with 1.5 %, the breeds show no difference in the amount of valuable meet cuts. In contrast to the former ETH beef cow project, in which Angus x Simmental crossbred calves had higher daily gain and carcass performance than pure-bred Angus calves, in this experiment the difference concerning the used genetics was insignificant.
Pontiggia A., Münger A., Ammer S., Philipona C., Bruckmaier R. M., Keil N.M., Dohme-Meier F.
Even in temperate climate zones, an increase in the ambient temperature and solar radiation can cause heat stress in grazing dairy cows. Agroscope studied the physiological changes in cows caused by increasing heat load.
Lazzari G., Münger A., Heimo D., Seifert S., Camarinha-Silva A., Borda-Molina D., Zähner M., Schrade S., Kreuzer M., Dohme-Meier F.
In dairy cows, herbage-based diets often lead to increased nitrogen excretion. Tanniferous sainfoin and extract of acacia can reduce nitrogen excretion from urine and thus ammonia volatilization from slurry.
Excessive nitrogen inputs from the air lead to over-fertilisation of sensitive ecosystems. Continuous feeding optimisation can make an important contribution to reducing ammonia losses and thus nitrogen inputs.