The aim of this study was to compare the supply of grass and the intake of three herds (test variants) over the 2012 and 2013 grazing seasons. The first herd received no supplement (control group G), whilst the other two benefited respectively from a barley (B) and whey (W) supplement. The quantity of grass offered was evaluated each week along the same marked lines with a rising plate pasture meter. The quantities of forage available to the three herds were roughly comparable in 2012 and very similar in 2013. The intake estimates, also made by measuring the height of the grass cover (entrance – exit differences), highlighted a marginally significant difference (P = 0.052) between the herds in 2012. The animals receiving a barley supplement consumed 7.7 kg DM/day (seasonal average), relative to 9.3 and 8.5 kg DM/day for the G and W groups, respectively. This substitution effect was not observed as clearly in 2013 (P = 0.149). The alkane technique (use of an indigestible marker) was also utilised over a four-day experimental period in June 2013. Although of the same order of magnitude as those obtained with the pasture meter, the values cannot be compared directly owing to differences in the methodology and
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.