Supplementation of Dairy Cow Diets with Ammonium Salts of Volatile Fatty Acids

Abstract

The objective was to determine the efficacy of a blend of ammonium salts of the volatile fatty acids, isobutyric, 2-methylbutyric, isovaleric, and valeric as a supplement to diets for dairy cows. Treatments of 0 (control) or 120 (supplemented) g/cow of the blend were fed daily from approximately 3 wk prepartum through a complete lactation. Five trials were conducted concurrently with a total of 116 multiparous Holstein cows. Dietary ingredients or combinations of ingredients differed in each of the trials. Diets contained either 1) corn gluten meal and urea, 2) soybean meal, or 3) cottonseed meal as the primary grain source of crude protein. The forage portion of the diets contained corn silage in combination with one or more of the following: alfalfa hay, alfalfa haylage, or wheat silage. Cows fed the supplement produced more milk and fat-corrected milk than the control cows for the 305-d lactation on four of the five diets, resulting in an average increase of 1.7 kg/d or 7%. Feed intake of cows on the supplemented diet was generally similar or lower than intake of the control cows throughout lactation, indicating that increased milk yield was associated with improved feed utilization. Percent milk fat was similar for cows on the supplemented diet, but fat yield was higher. Percent milk protein was lower for supplemented cows, but protein yield was about the same for both treatments because of higher milk yield. Health and reproduction were similar for all cows.

Effects of diet fermentability and supplementation of 2-hydroxy-4-(methylthio)-butanoic acid and isoacids on milk fat depression: 1. Production, milk fatty acid profile, and nutrient digestibility

“…Supplementation of IA increased milk fat yield by increasing milk fat content but not milk volume, and the increased milk fat content resulted from increased de novo synthesis of milk FA. Increased milk fat yield is consistent with results from most studies in which individual BCVFA, IA, or IA without valerate were fed to cows (Papas et al, 1984;Peirce-Sandner et al, 1985;Wang et al, 2019). Similar results were also observed in a study by Liu et al (2018).…”

“…This could be an evidence of IA stimulating milk fat synthesis because acetate supplementation can increase milk fat synthesis (Urrutia et al, 2019). Previous in vivo studies (Papas et al, 1984;Peirce-Sandner et al, 1985;Liu et al, 2018;Wang et al, 2019) also showed that supplemental IA increases fiber digestion or milk fat yield in dairy cows and could be effective in alleviating MFD.…”

Rapeseed meal as a supplementary protein for dairy cows on grass silage-based diet, with the emphasis on the Nordic AAT-PBV feed protein evaluation system

“…Linear multiple regressions estimating response in milk yield and protein content: Y=a + bjX, + b 2X 2 (X, = change in RSM intake; X 2 = change in ME total -ME rsm ). valine, isoleucine and proline) has increased the milk production of dairy cows (Papas et al 1984, Peirce-Sandner et al 1985).…”

Effects of diet fermentability and supplementation of 2-hydroxy-4-(methylthio)-butanoic acid and isoacids on milk fat depression: 2. Ruminal fermentation, fatty acid, and bacterial community structure

“…Branched-chain VFA (BCVFA; isoacids without the straight chain, valerate) are required by microbes to synthesize branched-chain amino acids (BCAA) or branched long-chain fatty acids (FA; cell membrane constituent; Allison et al, 1962;Maczulak et al, 1981). In addition, supplementation with IA often increased fiber digestibility and milk fat yield (Peirce-Sandner et al, 1985;Wang et al, 2019). Butyrivibrio proteoclasticus, the major characterized stearate producer, was hypothesized to be very susceptible to inhibition by free PUFA and was recognized for very high C16:0 iso (derived from isobutyrate) and C17:0 anteiso (derived from 2-methylbutyrate) composition of its membranes (Hackmann and Firkins, 2015).…”