Effectiveness of rubber seed oil and flaxseed oil to enhance the α-linolenic acid content in milk from dairy cows

Abstract

This experiment was conducted to investigate effect of rubber seed oil compared with flaxseed oil when fed alone or in combination on milk yield, milk composition, and α-linolenic acid (ALA) concentration in milk of dairy cows. Forty-eight mid-lactation Holstein dairy cows were randomly assigned to 1 of 4 treatments according to a completely randomized design. Cows were fed a basal diet (control; CON) or a basal diet supplemented with 4% rubber seed oil (RO), 4% flaxseed oil (FO), or 2% rubber seed oil plus 2% flaxseed oil (RFO) on a dry matter basis for 9 wk. Feed intake, milk protein percentage, and milk fat levels did not differ between the treatments. Cows fed the RO, FO, or RFO treatments had a higher milk yield than the CON group (up to 10.5% more), whereas milk fat percentages decreased. Compared with the CON, milk concentration of ALA was substantially higher in cows receiving RO or RFO, and was doubled in cows receiving FO. The ALA yield (g/d) increased by 31.0, 70.3, and 33.4% in milk from cows fed RO, FO, or RFO, respectively, compared with the CON. Both C18:1 trans-11 (vaccenic acid) and C18:2 cis-9,trans-11 (conjugated linoleic acid; CLA) levels were higher in cows fed added flaxseed or rubber seed oil. The CLA yield (g/d) increased by 336, 492, and 484% in cows fed RO, FO, or RFO, respectively, compared with the CON. The increase in vaccenic acid, ALA, and CLA was greater in cows fed RFO than in cows fed RO alone. Compared with the CON, the milk fat from cows fed any of the dietary supplements had a higher concentration of unsaturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids; conversely, the saturated fatty acids levels in milk fat were 30.5% lower. Insulin and growth hormones were not affected by dietary treatments; however, we noted an increase in both cholesterol and nonesterified fatty acids levels in the RO, FO, or RFO treatments. These results indicate that rubber seed oil and flaxseed oil will increase milk production and the concentration of functional fatty acids (ALA, vaccenic acid, and CLA) in milk fat while decreasing the content of saturated fatty acids.

Production, milk and plasma fatty acid profile, and nutrient utilization in Jersey cows fed flaxseed oil and corn grain with different particle size

“…In fact, NE L of diets supplemented with 3% FSO was numerically greater than that of diets without FSO (1.75 vs. 1.64 Mcal/kg of DM, respectively; Table 2). Our results are consistent with those from previous studies where milk yield increased by an average of 10% in cows fed FSO ranging from 2 to 4% of the diet DM (Bu et al, 2007;Benchaar et al, 2012Benchaar et al, , 2014Pi et al, 2016). However, results of FSO supplementation on milk yield have been inconsistent.…”

“…In fact, the plasma proportions of 14:0 (P = 0.01) and 16:0 (P < 0.001) decreased, whereas plasma 18:0 increased (P < 0.001) in 3% FSO cows ( Table 7). The observed reductions of Σ<16C FA and Σ16C FA in milk, and elevated milk Σ18C FA in cows offered 3% FSO are in line with results from previous studies (Bu et al, 2007;Benchaar et al, 2012;Pi et al, 2016). Decreased milk proportions of individual odd-and branched-chain FA (Table 5) suggest less duodenal flow of microbial protein as these FA are supplied primarily by ruminal microorganisms (Fievez et al, 2012) or that FSO supplementation depressed the growth of ruminal microbes that synthesize odd-and branched-chain FA.…”

“…Feeding 3% FSO to lactating dairy cows had no effect on DMI (Table 4). Intake of DM was also not affected in studies where lactating dairy cows were fed FSO varying from 2 to 4% (Loor et al, 2005;Bu et al, 2007;Benchaar et al, 2012Benchaar et al, , 2014Pi et al, 2016). In contrast, DMI decreased by 35% in lactating dairy cows fed 5.8% FSO compared with the control treatment (Chilliard et al, 2009).…”

“…Literature reports have been inconsistent relative to the effects of FSO supplementation on milk true protein concentration and yield independent of the amount of FSO fed. For instance, supplementation of FSO ranging from 2 to 4% (Loor et al, 2005;Bu et al, 2007;Benchaar et al, 2012;Pi et al, 2016) did not affect the concentration and yield of milk protein in dairy cows. In contrast, feeding 3% FSO tended to decrease (Benchaar et al, 2014), whereas 4% FSO (Benchaar et al, 2015) decreased the concentration and yield of milk protein in dairy cows.…”

Rubber seed oil and flaxseed oil supplementation on serum fatty acid profile, oxidation stability of serum and milk, and immune function of dairy cows

“…Rubber seed oil (RO) is a by-product of the rubber industry, and the main origin of RO being in Guangdong, Guangxi, and Yunnan provinces of China. In RO, the levels of total UFA and PUFA can amount to 83% and 59%, respectively [10]. Flaxseed oil (FO) and RO are both rich in ALA.…”