Low Emission Feed : using feed additives to decrease methane production in dairy cows

Abstract

SUMMARYResearch into manipulating methane (CH 4 ) production as a result of enteric fermentation in ruminants currently receives global interest. Using feed additives may be a feasible strategy to mitigate CH 4 as they are supplied in such amounts that the basal diet composition will not be largely affected. The latter is relevant because ruminants have the capacity to convert human inedible feedstuffs into human edible energy and protein.However, the application of CH 4 mitigation feed additives may be hampered by several negative side effects including trade-offs with other environmental impacts, negative effects on animal performance, and lack of persistency of the mitigating effect. The research described in this thesis addresses both the mitigating effect of feed additives as well as its persistency. The main focus was on investigating additivity of the CH 4 mitigating effect of feed additives, on the adaptation of rumen microbes to long term feeding of feed additives, and on exploring the potential of rotational feeding of additives to avoid (or reduce) microbial adaptation.In an experiment with lactating dairy cows in climate respiration chambers to study potential interactions between the effects of feeding nitrate and docosahexaenoic acid (DHA; C22:6 n-3) on enteric CH 4 production, the effects of nitrate and DHA on CH 4 yield [g/kg dry matter intake (DMI)] and CH 4 intensity [g/kg fat-and protein-corrected milk (FPCM)], were additive (Chapter 2). Nitrate decreased CH 4 irrespective of the unit in which it was expressed, and the average decline in CH 4 emission corresponds to 85% of the stoichiometric potential of nitrate to decrease CH 4 . Feeding DHA had no effect on CH 4 yield, but resulted in a higher CH 4 intensity, because of milk fat depression. The interaction effect between nitrate and DHA on fiber digestibility indicated that negative effects of nitrate on apparent total tract digestibility of nutrients were alleviated by DHA, probably due to an altered feed intake pattern.Using an isotope measurement protocol in the same study, it was demonstrated that effects of nitrate as a CH 4 mitigating feed additive on fiber degradation in the rumen can be detected by evaluating diurnal patterns of 13 C enrichment of exhaled CO 2 (Chapter 3).Feeding nitrate, but not DHA, resulted in a pronounced increase in 13 C enrichment of CO 2 in the first 3 to 4 h after feeding only. Results support the hypothesis that effects of a feed additive on the rate of fiber degradation in the rumen can be detected by evaluating diurnal patterns of 13 C enrichment of CO 2 . A prerequisite for this detection method is that the main ration components differ in natural 13 C enrichment (e.g., C3 and C4 plants), and in content of the nutrients that are expected to be involved in a shift in fermentation (e.g., starch and fiber) or in degradability of a nutrient.In a combined in vivo and in vitro trial, the adaptation to CH 4 mitigating feed additives, viz.an essential oil blend or lauric acid (C12:0), compared with a control diet...

Evaluation of dietary addition of 2 essential oils from Achillea moschata, or their components (bornyl acetate, camphor, and eucalyptol) on in vitro ruminal fermentation and microbial community composition

“…Another issue in the search for feed additive-based mitigation strategies is that the rumen's microbial ecosystem may adapt to the inclusion of feed additives to the diet. In that case, only a transient reduction of CH 4 emissions may be achieved ( Klop, 2016 ). Cardozo et al.…”

Climate-smart livestock production: options for Nigerian farmers

“…The results of this practice according to the author are an efficient production (milk or meat) relative to the amount of methane emitted. Klop (2016) expressed the advantage of using feed additives to mitigate GHG emissions as they are supplied in such amounts that the basal diet composition will not be largely affected by the feed additives (Klop, 2016). Methane-reducing feed additives and supplements inhibit methanogens in the rumen, and subsequently reduce enteric methane emissions (Curnow, 2019).…”

Afwentelingen van methaan-mitigerendemaatregelen in melkvee

“…Ten slotte, kunnen additieven ook een negatieve uitwerking op de melkproductie en melksamenstelling hebben. In het onderzoek binnen project EmissieArm Veevoer hadden DHA (docohexaeenzuur) en laurinezuur een numeriek negatieve invloed op ofwel melkvetgehalte, melkeiwitgehalte of de productie van vet-en eiwit-gecorrigeerde melk (Klop, 2016). Dergelijke effecten kwamen niet tot in de CH4 emissie per kg voer.…”