In one experiment cows were fed high or low allowances of either kale or fodder beet both with silage or they were fed grass silage indoors in a cubicle housed system. Cows wintered on the high offering rates were fed 9kg drymatter (DM)/cow of fodder beet or kale grazed in the paddock along with 5kg DM/cow of grass silage to make a daily offering of 14kg DM/cow/day with those indoors fed ad lib silage.
Those on the low allowance were offered 6kg DM/cow of kale or fodder beet plus 3.5kg DM/cow of grass silage with the indoor silage fed cows also restricted to 9.5kg DM/cow/day. Those on the higher allowance gained around twice as much weight through the winter, at between 54 and 69kg, as those cows offered a low allowance with the cows on fodder beet gaining the most weight.
Cows on the ad lib silage diet indoors had the greatest body condition score (BCS) gain compared with any other diet but cows on the high crop and silage allowance also had a significantly higher BCS gain than cows on a restricted diet including those indoors.
Milk production for the first 35 days after calving was greater in the fodder beet fed cows at both allowances. However the high allowance fodder beet cows had a greater BCS loss after calving than the others.
In another experiment comparing silage fed indoors with kale, swedes and grass cows wintering on grass had the greatest BCS loss but subsequent milk production was similar and the interval from calving to the next conception was also similar.
The cows fed indoors had ad lib silage while those on kale had 8kg DM/cow of crop and 4kg DM/cow silage and those on swedes had 8kg swedes and 4kg silage.
Cows wintering on grass were allocated 12kg DM/cow pasture.
French said studies looking at wintering diets using high levels of kale with some diets 100% kale found no detrimental effect from not including silage in the diet on rumen health.
