Linseed: a valuable feedstuff for ruminants

Abstract

-Linseeds are used in ruminant feeding for a long time, but this feedstuff knows now increasing interest. Linseeds are rich in alpha-linolenic acid, a fatty acid from the omega-3 series. Despite an extensive biohydrogenation of dietary alpha-linolenic acid in the rumen, its concentration in milk and beef meat increases with linseed incorporation in diets; this increase is accompanied by that of other fatty acids produced during biohydrogenation, especially conjugated linoleic acids and trans 18:1 fatty acids. The increase in cow fertility due to omega-3 fatty acids has not been demonstrated. Furthermore, linseed incorporation in ruminant diets is one of the most efficient ways to decrease enteric methane emissions. In addition to a global mitigating effect of all lipid sources on methane, linseeds have a specific effect due to changes in rumen microbial ecosystem. The practical use of linseeds in ruminant feeding at a large scale requires the absence of negative effect at any step of the ruminant production system. An excessive supply of lipids from linseeds can have deleterious effects on digestive efficiency, milk fat and protein content, beef susceptibility to oxidation, milk and beef fatty acid composition, but when linseed incorporation in the diet does not exceed ca. 3% of additional fat, only positive effects are remaining. A challenge is the increase in linseed cropping to meet increased needs for animal feeding.Keywords: Linseed / milk / beef / omega-3 fatty acids / methane Résumé -La graine de lin : un aliment de choix pour les ruminants. La graine de lin est utilisée depuis longtemps dans l'alimentation des ruminants, mais son emploi suscite un regain d'intérêt. Le lin est en effet riche en acide alpha-linolénique, un acide gras de la série des oméga 3. En dépit d'une biohydrogénation poussée dans le rumen, sa concentration dans le lait et la viande bovine est accrue lorsque la ration est enrichie en graines de lin ; cet accroissement va de pair avec celui d'autres acides gras intermédiaires de la biohydrogénation comme les acides gras monoinsaturés trans et les acides linoléiques conjugués. L'amélioration de la fertilité des vaches liée à cet apport d'oméga 3 n'a pas été démontrée. Par ailleurs, l'incorporation de lin dans la ration des ruminants est un des moyens efficaces pour réduire l'émission de méthane entérique. Outre un effet de toutes les sources de lipides pour réduire le méthane, le lin a un effet spécifique lié à son action sur le microbiote ruminal. L'utilisation de la graine de lin à grande échelle dans l'alimentation des bovins nécessite qu'il n'ait pas d'effet négatif à quelque niveau du système de production. Un apport excessif de lipides du lin peut diminuer la digestibilité de la ration, les taux butyreux et protéique du lait, modifier sensiblement la composition en acides gras du lait et de la viande, et augmenter la susceptibilité à l'oxydation des produits. Toutefois, lorsque l'incorporation de lipides du lin ne dépasse pas 3 % environ de la ration, seuls les effets pos...

Plant oil supplements reduce methane emissions and improve milk fatty acid composition in dairy cows fed grass silage-based diets without affecting milk yield

“…The lack of effect of plant oils on milk fat can be attributed to the lack of changes in rumen fermentation in the diets based on restrictively fermented grass silage. The plant lipids reduced milk protein content, as expected (Doreau and Ferlay, 2015). Glucose deficiency due to substitution of lipids for readily fermentable carbohydrates might decrease rumen microbial protein synthesis and, consequently, AA available at mammary gland for milk protein synthesis (Wu and Huber, 1994).…”

Nitrogen fertilization changes the productivity and chemical composition of Brown and Golden flax grains

“…The increasing world population and consequent increase in food consumption, including that of soybeans and corn grain, directs a need for the evaluation of alternative ingredients to be used in animal nutrition, especially in ruminant supplementation. Among these ingredients, those that are able to modify the fatty acid (FA) profile of meat and/or milk fat have been widely researched, improving nutritional quality, mainly by increasing the proportion of polyunsaturated fatty acids in the final product (HURTAUD et al, 2010;FERLAY, 2015;RADIS et al, 2016;SILVA et al, 2018).…”

“…Linseed (Linum usitatissimum L.) is one such ingredient because it contains a high oil content (40%), comprising 55% 18:3 n3 (ω-3) (PETIT, 2010), and is also a source of dietary fiber and antioxidant compounds (PETIT, 2009). These characteristics have increased the conjugated linoleic acid (CLA) concentrations in milk from dairy cows (PETIT, 2015;FUKE;NORNBERG, 2017), which has been associated with reduced incidence of cardiovascular disease, hypercholesterolemia, and some types of cancer in humans (PETIT, 2009;FERLAY, 2015). Linseed fatty acids (FA) have also been shown to reduce enteric methane emissions from ruminants (MARTIN et al, 2016), decreasing greenhouse gas emissions by sequestering hydrogen from the rumen environment.…”

Consolidated Properties and New Perspectives for Polyunsaturated Fatty Acids in Ruminant Diet

“…38,40 Substitution of dietary carbohydrates with lipids can reduce methane emission and decrease rumen protozoa which are producers of hydrogen, the precursor of methane. 15 Interestingly, linseeds rich in n-3 PUFA have been shown to reduce methane yield more efficiently than saturated (calcium salts of palm oil, tallow) and unsaturated sources containing oleic acid (rapeseed) or linoleic acid (sunflower, cottonseed). 15,38 Very recently, the possibility to reduce methane production by adding fish oil in low-starch diets has been demonstrated.…”

“…15 Interestingly, linseeds rich in n-3 PUFA have been shown to reduce methane yield more efficiently than saturated (calcium salts of palm oil, tallow) and unsaturated sources containing oleic acid (rapeseed) or linoleic acid (sunflower, cottonseed). 15,38 Very recently, the possibility to reduce methane production by adding fish oil in low-starch diets has been demonstrated. 41 Also increasing doses of coconut and fish oil quadratically decreased concentration of methane in vitro.…”