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

Abstract

We aimed to compare the effects of ground (GC) or cracked corn (CC), with or without flaxseed oil (FSO), on milk yield, milk and plasma fatty acid (FA) profile, and nutrient digestibility in Jersey cows fed diets formulated to contain similar starch concentrations. Twelve multiparous organic-certified Jersey cows averaging (mean ± standard deviation) 455 ± 41.9 kg of body weight and 152 ± 34 d in milk and 4 primiparous organic-certified Jersey cows averaging (mean ± standard deviation) 356 ± 2.41 kg of body weight and 174 ± 30 d in milk in the beginning of the experiment were used. Cows were randomly assigned to treatment sequences in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments. Each period lasted 24 d with 18 d for diet adaptation and 6 d for data and sample collection. Treatments were fed as total mixed rations consisting of (dry matter basis): (1) 0% FSO + 27.1% GC, (2) 0% FSO + 28.3% CC, (3) 3% FSO + 27.1% GC, and (4) 3% FSO + 28.3% CC. All cows were offered 55% of the total diet dry matter as mixed grass-legume baleage and treatments averaged 20% starch. Significant FSO × corn grain particle size interactions were observed for some variables including milk concentration of lactose and proportions of cis-9,cis-12,cis-15 18:3 in milk and plasma. The proportion of cis-9,cis-12,cis-15 18:3 in milk and plasma decreased slightly when comparing GC versus CC in 0% FSO cows, but a larger reduction was observed in 3% FSO cows. Dry matter intake did not differ and averaged 16.1 kg/d across diets. Feeding 3% FSO increased yields of milk and milk fat and lactose and feed and milk N efficiencies, but decreased fat, true protein, and MUN concentrations and apparent total-tract digestibility of fiber. The Σ branched-chain, Σ<16C, Σ16C, and Σn-6 FA decreased, whereas Σ18C, Σcis-18:1, and Σtrans-18:1 FA increased in 3% versus 0% FSO cows. No effect of corn particle size was observed for production and milk components. However, the apparent total-tract digestibility of starch was greater in GC than CC cows. Compared with CC, GC increased Σ branched-chain, Σ<16C, Σ16C, Σn-6 FA, and decreased Σ18C and Σ cis-18:1 FA in milk fat. Overall, results of this study are more directly applicable to dairy cows fed low starch, mixed grass-legume baleage-based diets.

Production, milk fatty acid profile, and nutrient utilization in grazing dairy cows supplemented with ground flaxseed

“…Likewise, elevated Σtrans-18:1 FA and Σcis-18:1 FA reflects increased intake of ALA (+146 g/d; P < 0.001; data not shown) in cows offered FLX versus the CTRL diet. Similar responses have been reported in confined dairy cows fed TMR containing GFLX (Petit and Côrtes, 2010;Resende et al, 2015) or flaxseed oil (Brossillon et al, 2018), and in grazing dairy cows supplemented with increasing levels of flaxseed oil (Flowers et al, 2008).…”

Supplementing Dairy Ewes Grazing Low Quality Pastures with Plant-Derived and Rumen-Protected Oils Containing Eicosapentaenoic Acid and Docosahexaenoic Acid Pellets Increases Body Condition Score and Milk, Fat, and Protein Yields

“…These findings were in contrast with other authors who distinguished either an increase [27] or a decrease [28] in milk yield of dairy ewes fed 250 g/day of whole flaxseed or 200 g/day of extruded flaxseed, respectively. Milk fat depression in response to supplementation with FSO in this study was supported by other studies in sheep [53] and cows [34,55,56], but disagrees with others that showed no changes in sheep [27,52,54] or a minor increase in sheep [26,28] and goats [57]. These variations might be due to the multi nutritional effects, including energy balance, NDF concentration, and feed particle size, that have strong correlations with milk yield and milk fat concentration [11].…”

Performance and feeding behavior of dairy cows fed high-concentrate diets containing steam-flaked or ground corn varying in particle size

“…The effect of PS of GC on DMI has been inconsistent in the literature. The lack of difference in DMI due to GC processing in the present study is similar to the findings of Callison et al (2001), Remond et al (2004), Fredin et al (2015, and Brossillon et al (2018), but contrast with the study of De Nardi et al (2014) who reported that cows offered finely GC had greater DMI compared with those offered coarse GC. According to Allen (2000), stimulating the distention receptors located in the rumen epithelium and increasing hepatic oxidation can decrease DMI.…”