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

Abstract

Flaxseed has been extensively used as a supplement for dairy cows because of its high concentrations of energy and the n-3 fatty acid (FA) cis-9,cis-12,cis-15 18:3. However, limited information is available regarding the effect of ground flaxseed on dry matter intake (DMI), ruminal fermentation, and nutrient utilization in grazing dairy cows. Twenty multiparous Jersey cows averaging (mean ± standard deviation) 111 ± 49 d in milk in the beginning of the study were used in a randomized complete block design to investigate the effects of supplementing herbage (i.e., grazed forage) with ground corn-soybean meal mix (control diet = CTRL) or ground flaxseed (flaxseed diet = FLX) on animal production, milk FA, ruminal metabolism, and nutrient digestibility. The study was conducted from June to September 2013, with data and sample collection taking place on wk 4, 8, 12, and 16. Cows were fed a diet formulated to yield a 60:40 forage-to-concentrate ratio consisting of (dry matter basis): 40% cool-season perennial herbage, 50% partial total mixed ration, and 10% of ground corn-soybean meal mix or 10% ground flaxseed. However, estimated herbage DMI averaged 5.59 kg/d or 34% of the total DMI. Significant treatment by week interactions were observed for milk and blood urea N, and several milk FA (e.g., trans-10 18:1). No significant differences between treatments were observed for herbage and total DMI, milk yield, feed efficiency, concentrations and yields of milk components, and urinary excretion of purine derivatives. Total-tract digestibility of organic matter decreased, whereas that of neutral detergent fiber increased with feeding FLX versus CTRL. No treatment effects were observed for ruminal concentrations of total volatile FA and NH 3 -N, and ruminal proportions of acetate and propionate.Ruminal butyrate tended to decrease, and the acetateto-propionate ratio decreased in the FLX diet. Most saturated and unsaturated FA in milk fat were changed. Specifically, milk proportion of cis-9,cis-12,cis-15 18:3, Σn-3 FA, and Σ18C FA increased, whereas that of cis-9,cis-12 18:2, Σn-6 FA, Σ odd-chain FA, Σ<16C FA, and Σ16C FA decreased with feeding FLX versus the CTRL diet. In conclusion, feeding FLX did not change yields of milk and milk components, but increased milk n-3 FA. Therefore, costs and industry adoption of premiums for n-3-enriched milk will determine the adoption of ground flaxseed in pasture-based dairy farms.

Influence of flaxseed with rumen undegradable protein level on milk yield, milk fatty acids and blood metabolites in transition ewes

“…The intermediates of these unsaturated FA which are produced during biohydrogenation in the rumen, can inhibit de novo FA synthesis in the mammary gland and would cause a relative reduction in short and medium-chain FA [ 56 ], as seen in Table 5 . In the current study, a decrease in odd and branched-chain FA (C15:0 and C17:0) following the inclusion of extruded or whole flaxseed is consistent to Isenberg et al [ 58 ]. This reduction could be due to the variation in the rumen bacterial population since most of these FA derived from bacteria leaving the rumen [ 59 ].…”

Fatty Acid Profile and Enterolactone Content of Early and Commercial Milk of Dairy Cows Supplemented with Flaked Flaxseed during the Dry Period

“…Supplementation with n-3 FA of cattle feeding is an effective approach for improving the nutritional value of animal products such as meat and milk [3,15,31,32]. Many studies [9,10,17,32] demonstrated that flaxseed supplementation in cows during lactation or transition periods significantly increase the amount of n-3 FA in milk, which is otherwise relatively poor in these FA [33]. Nevertheless, very few studies have been conducted on the effects of pre-partum n-3 supplementation on milk composition [13,15].…”

“…Flaxseed (Linum usitatissimum) is known as an excellent source of unsaturated fatty acids (FA), particularly of alpha-linolenic acid (ALA, C18:3n-3), a member of n-3 FA [2]. A large number of studies have reported the results of flaxseeds inclusion in diets for lactating dairy cows finalized to enrich milk [7][8][9] and derivate [10] in n-3 FA. In addition, several studies have shown that the incorporation of dietary n-3 into ovarian structures and bull sperm influence the reproductive features in terms of follicular and embryo development, and bull semen quality [11].…”

Histórico, Usos E Importância Econômica Da Linhaça

“…Assim, estudos que avaliaram a moagem da linhaça mostraram que o fornecimento de 100 e 120 g de linhaça moída kg -1 MS na dieta de vacas, no terço médio de lactação não altera a produção e concentração da gordura do leite, a produção de leite e consumo de alimento (SILVA, et al, 2007;ISENBERG, et al, 2019), entretanto, melhora na composição da gordura. O fornecimento de 10% de linhaça moída reduziu em 12% a concentração de AGS, aumentou a concentração de AGI em 23%, de ácido rumênico em 4%, oleico em 34%, C18:2 trans-10, cis-12 em 100% e ômega 3 em 75%, quando comparado ao leite de vacas suplementadas com milho e farelo de soja (ISENBERG et al, 2019). O fornecimento de 120 g de linhaça moída kg -1 MS aumentou a concentração de AGPI em 25%, ômega 3 em 34% e ácido rumênico em 35%; além de reduzir em 2% a concentração de AGS, e 5% a concentração do ácido esteárico, quando comparado ao de leite de vacas alimentadas com linhaça inteira (SILVA, et al, 2007).…”