12 March 2013

2 minute read

Fresh buckwheat (Fagopyrum esculentum) and chicory (Cichorium intybus) had been shown to have the potential to improve certain milk quality traits when fed as forages to dairy cows. However, the process of ensiling might alter these properties.

The Study

In the present study, two silages, prepared from mixtures of buckwheat or chicory and ryegrass, were compared with pure ryegrass silage (Lolium multiflorum) by feeding to 3 × 6 late-lactating cows. The dietary dry matter proportions realised for buckwheat and chicory were 0·46 and 0·34 accounting also for 2 kg/d of concentrate.

Data and samples were collected from days 10 to 15 of treatment feeding. Buckwheat silage was richest in condensed tannins. Proportions of polyunsaturated fatty acids (PUFA) and ?-linoleic acid in total fatty acids (FA) were highest in the ryegrass silage.

Feed intake, milk yield and milk gross composition did not differ among the groups. Feeding buckwheat resulted in the highest milk fat concentrations (g/kg) of linoleic acid (15·7) and total PUFA (40·5; both P < 0·05 compared with ryegrass).

The concentration of linolenic acid in milk fat was similar across treatments, but its apparent recovery in milk relative to the amounts ingested was highest with buckwheat. The same was true for the occurrence of FA biohydrogenation products in milk relative to ?-linolenic acid intake.

Recovery of dietary linoleic acid in milk remained unaffected. Feeding buckwheat silage shortened rennet coagulation time by 26 per cent and tended (P < 0·1) to increase curd firmness by 29 per cent. In conclusion, particularly buckwheat silage seems to have a certain potential to modify the transfer of FA from feed to milk and to contribute to improved cheese-making properties.