Analysis of longterm trends in the performance of dairy cows on low-input mountain farms

The productive and reproductive performance of dairy cows was examined on thirty-four low-input farms in the Sumava Mts. between 2000 and 2007. Milk production increased by an average of 986 kg and 948 kg per lactation by Holstein and by Czech Fleckvieh cows, respectively (P < 0.001), while the mean number of lactations decreased from 2.7 to 2.5 in Holstein and from 3.4. to 3.0 in Czech Fleckvieh cows (P < 0.001) in the same period. The mean number of lactations decreased also in the culled cows – from 3.2 to 2.9 by Holstein and from 4.3 to 3.5 by Czech Fleckvieh cows (P < 0.001). A higher cow milk yield was accompanied by a deterioration in reproductive performance. Between the periods 2000–2003 and 2004– 2007 the number of days open lengthened by an average of 6 and 4 days (P < 0.01) and the calving period by an average of 11 and 6 days (P < 0.001) in Holstein and Czech Fleckvieh cows respectively. The results indicated an increased replacement of cows in the herds examined as a coincidental feature of the steadily rising milk performance. This may have a negative impact on the rentability of low-input mountain dairy farming in the region.