Whole flax seed and flax oil supplementation of dairy cows fed high-forage or high-concentrate diets: Effects on digestion, ruminal fermentation characteristics, protozoal populations and milk fatty acid profile

Effects of extruded flaxseed and Salmate® inclusion in the diet on milk yield and composition, ruminal fermentation and degradation, and kinetic flow of digesta and fluid in lactating dairy cows in the subtropics

Background and Aim

Dietary supplements play pivotal roles in promoting productive and reproductive performance in ruminant animals. The aims of the present study were to evaluate the effects of extruded flaxseed and Salmate® (Ballard Group, Inc, OH, USA) inclusion in diets on milk yield and composition, ruminal degradation and fermentation, and flow of fluids and digesta in lactating cattle.

Materials and Methods

Six rumen-fistulated Holstein lactating cows were distributed to a 6 × 6 design of Latin square (L.S.). The groups were assorted into a control group fed a basal control diet and two treated groups fed diets containing extruded flaxseed (7.0%) or Salmate® (25 g/head/day). The basal control, extruded flaxseed, and Salmate® diets were formulated as isonitrogenous and isoenergetic. Each L.S. period of the group comprised 21 days, including 10 days for adaptation to the diet and 11 days for data sampling and recording.

Results

Feed intake did not differ among the control, extruded flaxseed, and Salmate® groups. Milk yield (kg) and protein and fat composition (%) were improved on feeding the extruded flaxseed diet compared with the Salmate® and control diets. Extruded flaxseed or Salmate® diet had no effect on the values of ruminal pH, ammonia, and volatile fatty acids except isobutyrate, which decreased in the Salmate® group. Degradable efficiency and ruminal digestibility were significantly decreased with the inclusion of extruded flaxseed and/or Salmate® in the diets. The extruded flaxseed and Salmate® groups had a greater digesta passage rate than the control group. The extruded flaxseed and control groups had a greater liquid passage rate than the Salmate® group.

Conclusion

The inclusion of extruded flaxseed in the diet improved (p < 0.05) milk yield, milk composition, and milk Omega-6: Omega-3 ratio with no changes in ruminal fermentation, notable negative effects on degradable efficiency and ruminal digestibility.

In vitro rumen fermentation pattern: insights from concentrate level and plant oil supplement

The addition of oil to ruminant diets and oil fatty acid profiles are major factors that negatively affect ruminal fermentation, while increased forage level attenuates the adverse effects. The aim of this study was to determine the effects of oil source supplementation and concentrate level in the diet on in vitro ruminal fermentation kinetics. Pomegranate, garlic or sunflower oils were added (2 % dry matter (DM) basis) to the diets containing 40 % or 60 % (DM basis) concentrates. In vitro gas production parameters, pH, ammonia nitrogen concentration and total protozoa count were measured. Additionally, metabolizable energy (ME), short-chain fatty acid (SCFA) production and organic matter digestibility (OMD) were determined. Rumen fermentation parameters and protozoal population counts were analyzed as a completely randomized design with a 2  ×  3 factorial arrangement of treatments, and gas production parameters were analyzed as a 2  ×  3 factorial arrangement in a randomized block design. The results showed that the HCPO (high (60 %) concentrate diet containing pomegranate oil) and HCSO (high (60 %) concentrate diet containing sunflower oil) diets produced the highest (5.40 mg dL - 1 ) and lowest (2.61 mg dL - 1 ) concentrations of NH 3 -N ( p > 0.01 ), respectively. Total protozoa count tended ( p = 0.07 ) to be highest in HCPO and lowest in HCSO diets (5.10 vs. 4.81 Log 10 g - 1 digesta). No interaction effects between the concentrate level and oil source were found on in vitro gas production parameters, pH, estimated ME, SCFA and OMD, and Entodinium and Diplodinium populations ( p > 0.05 ). It is concluded that dietary supplementation with highly unsaturated oil from three different sources at 2 % level (DM basis) had no apparent effects on in vitro ruminal fermentation patterns.

Effect of carbohydrate hydrolytic enzyme complex in combination with energy feed on rumen digestion, metabolism, productivity and fatty acid composition of milk fat in cows

The research was carried out on 2 groups of dairy cows of 30 heads on the farm with the formation of technological groups according to the timing of calving and milking on the unit with individual accounting of milk yield. Cows of the experimental group in the period two weeks before calving and for 2 months after calving were added to the diet, respectively, 150 and 300 ml / head / day energy feed based on propylene glycol and glycerin with a complex of enzymes cellulase, xylase, beta-gluconase and glucoamylase activity (EFEC). The main diet consisted of traditional feed and was designed to receive an average daily milk yield of 25 kg of milk. EFEC had practically no effect on the pH and ammonia content in the rumen chyme, but increased the content of VFA in it by 3.6%. It had no effect on the total microbial mass, but reduced the population of infusoria by 23.5% and increased the bacterial population by 27.8%. EFEC had a positive effect on protein-nitrogen metabolism, liver function, antioxidant activity, hormonal status and hematology. As a result, during 3 months of lactation, the average daily milk yield in cows of the experimental group was 19.9, 20.9 and 21.1 kg of milk (P<0.001), which was higher than in the control by 13.0, 9.4 and 16.5%, respectively.

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

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.

The relationships between odd- and branched-chain fatty acids to ruminal fermentation parameters and bacterial populations with different dietary ratios of forage and concentrate

The objectives of this study were to investigate the effect of different dietary ratios of forage and concentrate (F:C) on ruminal odd- and branched-chain fatty acids (OBCFAs) contents and to evaluate the relationships between OBCFA and ruminal fermentation parameters as well as bacterial populations tested by real-time PCR technique. The experimental design was a 3 × 3 Latin square. Three rumen-fistulated dry Holstein cows were fed three rations with different dietary F:C ratios (F:C; 30:70, 50:50 and 70:30). The rumen samples were collected every two hours (0600, 0800, 1000, 1200, 1400, 1600, 1800, 2000, 2200, 2400, 0200 and 0400 h) over three consecutive days in each sampling period. The results showed that rumen OBCFA profiles are significantly (p < 0.05) affected by the dietary F:C ratios. The concentrations of C11:0, C13:0, iso-C15:0, iso-C16:0, iso-C17:0 and C17:0 were higher in the cows fed dietary F:C ratio of 70:30 than those fed with other two rations. However, the concentrations of anteiso-C15:0, C15:0 and total OBCFA were on the lowest level in the high forage diet. Correlation and regression analysis showed that ruminal OBCFAs had strong relationships with ruminal fermentation parameters and bacterial populations. In particular, the iso-fatty acids had potential power to predict butyrate and isoacids metabolized in the rumen, whereas the fatty acids with 17 carbon atoms correlated with ruminal NH₃ -N content. The OBCFA contents have different relationships with fibrolytic and starch bacteria in the rumen. C17:0 and its isomers might be used to predict populations of fibrolytic bacteria.