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Effect of a whey protein and rapeseed oil gel feed supplement on milk fatty acid composition of Holstein cows

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Version 2 2024-06-04, 06:11
Version 1 2019-01-30, 15:37
journal contribution
posted on 2024-06-04, 06:11 authored by KE Kliem, DJ Humphries, AS Grandison, R Morgan, Katherine LivingstoneKatherine Livingstone, DI Givens, CK Reynolds
Isoenergetic replacement of dietary saturated fatty acids (SFA) with cis-monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) can reduce cardiovascular disease risk. Supplementing dairy cow diets with plant oils lowers milk fat SFA concentrations. However, this feeding strategy can also increase milk fat trans fatty acids (FA) and negatively affect rumen fermentation. Protection of oil supplements from the rumen environment is therefore needed. In the present study a whey protein gel (WPG) of rapeseed oil (RO) was produced for feeding to dairy cows, in 2 experiments. In experiment 1, four multiparous Holstein-Friesian cows in mid-lactation were used in a change-over experiment, with 8-d treatment periods separated by a 5-d washout period. Total mixed ration diets containing 420 g of RO or WPG providing 420 g of RO were fed and the effects on milk production, composition, and FA concentration were measured. Experiment 2 involved 4 multiparous mid-lactation Holstein-Friesian cows in a 4 × 4 Latin square design experiment, with 28-d periods, to investigate the effect of incremental dietary inclusion (0, 271, 617, and 814 g/d supplemental oil) of WPG on milk production, composition, and FA concentration in the last week of each period. Whey protein gel had minimal effects on milk FA profile in experiment 1, but trans-18:1 and total trans-MUFA were higher after 8 d of supplementation with RO than with WPG. Incremental diet inclusion of WPG in experiment 2 resulted in linear increases in milk yield, cis- and trans-MUFA and PUFA, and linear decreases in SFA (from 73 to 58 g/100 g of FA) and milk fat concentration. The WPG supplement was effective at decreasing milk SFA concentration by replacement with MUFA and PUFA in experiment 2, but the increase in trans FA suggested that protection was incomplete.

History

Journal

Journal of Dairy Science

Volume

102

Pagination

288-300

Location

United States

Open access

  • Yes

ISSN

0022-0302

eISSN

1525-3198

Language

English

Publication classification

C1 Refereed article in a scholarly journal

Copyright notice

2019, American Dairy Science Association

Issue

1

Publisher

ELSEVIER SCIENCE INC