Browsing by Author "Ojala, Kasperi"

Self-sufficiency in protein feeds is low in Finland. Therefore there has been interest towards the use of domestic faba bean (Vicia faba) in dairy cow feeding. Faba bean is rich in starch and crude protein but the crude protein is highly degradable in the rumen. Moreover, faba bean protein contains low concentrations of sulfur containing amino acids, especially methionine, which can limit dairy cow’s production. The aim of this study was to examine if it is possible to increase faba bean protein utilization in the mammary gland by industrial treatment and by methiohine infusion into abomasum. The study was conducted at the University of Helsinki research farm in Viikki from 6.1.2018 to 21.4.2018. The experimental design was 5 x 5 latin square with 21-d experimental periods and five rumen fistulated multiparous ayrshire cows. The five isonitrogenous treatments were rapeseed meal (R), milled faba bean (MF), milled faba bean with methionine infusion (15 g/d into abomasum; MF+), industrially treated faba bean (TF) and industrially treated faba bean with methionine infusion (TF+). The cows were fed total mixed ration (TMR) ad libitum with concentrate-to-forage ratio of 38:62 in dry matter (DM). Faba bean diets increased daily DM intake (DMI) by an average of 1.6 kg compared to rapeseed meal diet but this had no effect on daily milk yield which was on average 27.7 kg. Faba bean diets increased starch and crude protein intakes with the result of increased microbial protein sythesis in the rumen and increased milk protein concentration. Industrial treatment of faba bean tended to increase daily milk yield on average of 1.4 kg which is probably a result of increased absorption of glucose and metabolizable protein in the small intestine. Methionine infusion increased plasma methionine concentration but this had no effects on DMI, milk yield or milk composition or nitrogen utilization. The utilization of feed protein to milk protein was only on average 25.2 % and it was not affected by diet. The results of this study suggest that faba bean is palatable protein feed and has potential to replace rapeseed meal in dairy cow feeding. It is possible to reduce ruminal crude protein and starch degradability of faba bean by industrial treatment. Methionine infusion had no effects on dairy cow’s performance so it can be concluded that methionine was not limiting amino acid in this study.