Tackling the future challenges of Organic Animal Husbandry - vTI

Abstract
RAHMANN G & GODINHO D (Ed.) (2012): Tackling the Future Challenges of Organic Animal Husbandry.
Proceedings of the 2 nd OAHC, Hamburg/Trenthorst, Germany, Sep 12-14, 2012
Cold-pressed rapeseed cake or rapeseed to dairy cows
– milk production and profitability –
BIRGITTA JOHANSSON, KARL-IVAR KUMM,
ELISABET NADEAU
1 Department of Animal Environment and Health, Swedish University of Agricultural Sciences,
Skara, Sweden, eMail: birgitta.johansson@slu.se
Some cases in Sweden have shown that feeds grown on the own farm contributes less to environmental
problems than imported feeds. Rapeseed and its co-product cold-pressed rapeseed cake
(CORC) can both be locally produced and CORC has been proven to be suitable for dairy cows. In
both feeds the fat content is limiting the amount that can be used in the diet. In a study with scenario
calculations, using CORC was, however, found to give a lower financial output than using rapeseed.
The aim of the study was to find out how milk yield, milk composition, cow health and fertility
were influenced by feeding rapeseed compared to CORC in organic diets, and to calculate the profitability
outcome. The study was performed during the indoor period 2009-2010 on 56 Swedish
Holstein cows. The diet was 100 % organic and included a mixed ration (silage, grains and minerals)
fed ad libitum and a restricted amount of concentrates (CORC vs. ground rapeseed, and field
beans that were fed in both treatments). Based on results on milk production and feed consumption
and prices of milk and feeds, the financial outcome for each treatment was calculated. There were
no significant differences found in milk yield and composition between the feed treatments. However,
cows fed rapeseed had a higher intake of the mixed ration than the cows fed CORC, which led to
a higher profitability for cows fed the CORC compared to cows fed rapeseed, especially in later
lactation.
Key words: rapeseed, cake, organic milk production, dairy cow, profitability
Introduction
Home-grown feeds cause less environmental problems (Strid, 2010) and result in less greenhouse
gas emissions (Flysjö et al, 2008) than imported feeds. It may also be economically beneficial for
the farmer to increase the proportion of home-grown feed in the diets. The protein in locally produced
protein feeds, such as legumes and oilseeds, contain relatively large amounts of rumen degradable
protein, which may contribute to decreased milk yield (Wu & Satter, 2000). However, if
the cow is simultaneously supplied with carbohydrates for the microbe synthesis, a good production
result can be achieved (Børsting et al, 2003). Rapeseed and its co-product cold-pressed rapeseed
cake (CORC) can both be locally produced and CORC has been proven to be suitable for dairy
cows (Johansson & Nadeau, 2006). The fat content of rapeseed and CORC limits the amount that
can be used in the diet (Johansson & Nadeau, 2006). However, rapeseed has a relatively slow release
of fat and can be fed in amounts of 1-2 kg per day with only small effects on cow metabolism
(Murphy et al, 1987). In a study with scenario calculations, diets including CORC were found to
give a lower financial output than diets including rapeseed (Mogensen, 2004). The aim of the study
was to investigate the effect of replacing CORC with rapeseed in organic diets on milk yield and
composition, cow health and fertility and to calculate the profitability of these feed rations.
Material and methodology
The study was performed during the indoor period 2009-2010 on 56 Swedish Holstein cows in different
lactation stages at Tingvall Organic Farm, Sweden. The rolling herd average was 10842 kg
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