Contact/s:
Silvija Dreijere
silvija.dreijere@llkc.lv
Fat Supplementation of Dairy Cow Diets
Latvia
Temperate, Humid Continental
- Feed enrichment
- Reduction of methane emissions
- Fats in dairy cow diets
Thematic Areas
Production System/s
Summary for Practicioners on the Main Finding(s)/Innovative solution(s)
Fat enrichment involves increasing the proportion of certain feed ingredients—such as fatty substances (rapeseed, linseed, sunflower oil, rapeseed oil)—to 5–6% of dry matter in the feed. The primary effect of fat supplementation is to replace other energy sources, mainly carbohydrates, and to reduce methane production.
Scientific studies on sheep, cattle, and dairy cows in other countries (Beauchemin et al., 2008) have shown that for every 1% increase in fat (on a dry matter basis), CH₄ emissions decrease by 2.2–7.3%:
⦁ Coconut oil: 7.3% reduction
⦁ Soybean and sunflower oil: 4.1% reduction
⦁ Linseed oil: 4.8% reduction
⦁ Rapeseed oil: 2.5% reduction
⦁ Fats (saturated): 3.5% reduction
By formulating feed rations for dairy cows, it is evident that including rapeseed or rapeseed oil can reduce methane emissions by approximately 9%. This approach is a viable option not only for conventional farms but also for organic farms.
Reducing microbial activity in the rumen lowers fiber digestion and alters volatile fatty acid (VFA) profiles—acetic (60–70%), propionic (20–25%), and butyric acid (10–15%). Imbalances affect milk fat/protein and methane emissions. The acetic-to-propionic acid ratio influences hydrogen use for methane production; typical ratios range from 9:1 to 4:1. Proper feed composition can reduce methane losses. Studies show 5% dietary fat improves early lactation milk yield, with cows able to utilize 0.45 g/day of added fat. Grain-based diets with fat maintain energy and fiber intake. Supplementing up to 5% fat is effective, especially in large herds grouped by lactation phase. Fat enrichment reduces CH₄ emissions—1% more fat lowers emissions by 5%. Feed modeling shows rapeseed oil reduces methane by ~9%, offering a promising strategy for both organic and conventional farms to cut GHG emissions while maintaining productivity.
Summary for Practicioners in Native Language
Barības bagātināšana ar taukvielām pamatojas uz atsevišķu barības sastāvdaļu, t.i. taukvielu (rapšu sēklas, linsēklas, saulespuķu eļļa, rapša eļļas), īpatsvara palielināšanu barībā 5 līdz 6% apmērā no sausnas. Galvenā tauku ietekme izpaužas tā, ka ar taukiem barībā aizvieto citus enerģijas avotus, pamatā ogļhidrātus un samazina metāna veidošanos.
Zinātnieku pētījumos citās valstīs ar aitām, liellopiem un slaucamām govīm (Beauchemin et al., 2008), noskaidrots, ka katrs 1% tauku (uz sausni), samazina CH4 emisiju par 2,2–7,3% apmērā:
⦁ kokosriekstu eļļa par 7,3%;
⦁ sojas un saulespuķu eļļa par 4,1%;
⦁ linsēklu eļļa par 4,8%;
⦁ rapšu eļļa par 2,5%;
⦁ tauki ( piesātinātās taukskābes) par 3,5%.
Sastādot barības devas (sk.1.attēlu) slaucamajām govīm, redzams, ka metāna emisiju samazinājumu par ~9% varam panākt iekļaujot rapšu sēklas vai rapšu eļļu, kas ir reāls risinājums ne tikai konvencionālajās, bet arī bioloģiskajās saimniecībās.
Samazinot mikrobu aktivitāti spureklī, samazinās kokšķiedras sagremošana un mainās gaistošo taukskābju (VFA) – etiķskābes (60-70 %), propionskābes (20-25 %) un sviestskābes (10-15 %) – profils. Disbalanss ietekmē piena tauku/proteīnu un metāna emisiju. Etiķskābes un propionskābes attiecība ietekmē ūdeņraža izmantošanu metāna ražošanai; tipiskā attiecība ir no 9:1 līdz 4:1. Pareizs barības sastāvs var samazināt metāna zudumus. Pētījumi liecina, ka 5 % tauku daudzums barības devā uzlabo izslaukumu laktācijas sākumā, un govis var izmantot 0,45 g pievienoto tauku dienā. Uz graudiem balstītas barības devas ar taukiem saglabā enerģijas un kokšķiedras uzņemšanu. Tauku piedevas līdz 5 % ir efektīvas, jo īpaši lielos ganāmpulkos, kas sagrupēti pēc laktācijas fāzes. Tauku pievienošana samazina CH₄ emisijas – par 5% vairāk tauku samazina emisijas par 5%. Barības devu modelēšana liecina, ka rapšu eļļa samazina metānu par ~9%, piedāvājot daudzsološu stratēģiju gan bioloģiskajām, gan tradicionālajām saimniecībām, lai samazinātu SEG emisijas, vienlaikus saglabājot produktivitāti.
Additional Information
Fat enrichment involves increasing the proportion of certain feed ingredients, specifically fatty substances (rapeseed, linseed, sunflower oil, rapeseed oil), to 5–6% of dry matter in the feed. The primary effect of fat supplementation is to replace other energy sources, mainly carbohydrates, and to reduce methane production.
Research by international scientists has explored various strategies to reduce methane emissions from the intestinal tract of cattle, with one proposed solution being fat enrichment in feed through the inclusion of fatty acids.
Fat enrichment involves increasing the proportion of fatty acids in the diet by incorporating various vegetable oils (e.g., sunflower, rapeseed, linseed, hemp, cottonseed). Animal nutrition scientists in Latvia recommend adding vegetable oils to compound or complete mixed rations (TMR) at 5% of dry matter for dairy cows, pregnant heifers, breeding heifers, young stock (6–12months), and calves (3–6 months), and 3% for fattening and beef cattle(Latvian, 1991, 1998, 2013; Ositis, 2000).
Scientific studies on sheep, cattle, and dairy cows (Beauchemin et al., 2008)indicate that every 1% increase in fat (on a dry matter basis) reduces CH₄ emissions by 2.2–7.3%:
• Coconut oil: 7.3% reduction
• Soybean and sunflower oil: 4.1% reduction
• Linseed oil: 4.8% reduction
• Rapeseed oil: 2.5% reduction
• Saturated fats: 3.5% reduction
Fat supplementation partially replaces carbohydrates, which are fermented in the rumen, producing CH₄ as a by-product. In contrast, fat is processed in the intestine, where methane is not generated. Additionally, unsaturated fatty acids found in linseed, rapeseed, and sunflower seeds selectively inhibit certain microorganisms in the rumen, reducing their activity and there by lowering CH₄ emissions.
The reduction in microbial activity (infusoria, yeast fungi, bacteria) in the rumen decreases fiber digestion (cellulose, hemicellulose), impacting the formation of volatile fatty acids (VFAs):
• Acetic acid: 60–70%
• Propionic acid: 20–25%
• Butyric acid: 10–15%
An imbalance in these VFAs affects production, metabolism, and milk composition, as milk fat and protein content can decrease rapidly (Latvian,1991). The rumen fermentation mechanism regulates hydrogen availability for methane production. The acetic-to-propionic acid ratio is a key factor:
• If the ratio is 5:1, methane energy loss is 0%.
• If all carbohydrates ferment into acetic acid without propionic acid production, methane energy loss can reach 33%.
• Typical acetic-to-propionic acid ratios range from 9:1 to 4:1(Johnson and Johnson, 1995).
Since the formation of VFAs is influenced by feed composition, proper diet formulation plays a crucial role in methane reduction strategies.
Impact on Milk Production and GHG Emissions
Long-term studies indicate that 5% fat in total dry matter optimizes milk production in early lactation (Palmquist, 1983). In addition to naturally occurring fats, cows can utilize an additional 0.45 g/day of fat (Palmquist,1983).
The most accessible energy source for dairy cows is grain. Adding fat to starchy, grain-based diets maintains high energy levels while allowing for adequate fiber intake (Palmquist and Conrad, 1980). Fat supplementation up to 5% of dry matter at the start of lactation helps address energy deficits without negatively impacting metabolism and production. This strategy is particularly effective on farms grouping cows by lactation phase, especially in herds with more than 50 cows (Project report: “Development of a methodology for estimation of GHG emissions from the agricultural sector and data analysis with modeling tools integrating climate change” Contract No 2014/94).
Impact of Fat Enrichment on GHG Emissions
Studies have shown that increasing dietary fat by 1% reduces CH₄ emissions by 5% (Grainger, Beauchemin, 2011). Feed ration modeling (see Figure 1)suggests that incorporating rapeseed or rapeseed oil can lower methane emissions by ~9%, making it a viable solution for both conventional and organic farms.