Effects of vegetable oil supplementation on rumen fermentation and microbial population in ruminant: a review

Abstract

Understanding the nature of ruminant nutrition and digestion is essential to improve feeding management and animal production. Among many approaches, manipulating ruminant nutrition and fermentation through feed supplementation is being practised and researched. Over the last decade, the utilization of vegetable oils in feed formulation and their effects on various aspects of ruminants have been reported by many researchers. It is important to understand the lipid metabolism in ruminants by microorganisms because it affects the quality of ruminant-derived products such as meat and milk. Majority of vegetable oil supplementation could reduce rumen protozoa population in ruminants due to the effects of medium-chain fatty acids (FAs). However, vegetable oil also contains unsaturated FAs that are known to have a negative effect on cellulolytic bacteria which could show inhibitory effects of the fibre digestion. In this paper, the physiology of nutrient digestion of ruminants is described. This paper also provides a current review of studies done on improvement and modification of rumen fermentation and microbial population through vegetable oil supplementation.

Altering Methane Emission, Fatty Acid Composition, and Microbial Profile during In Vitro Ruminant Fermentation by Manipulating Dietary Fatty Acid Ratios

“…This finding indicates that the n-6/n-3 ratio in the diet affects the FA composition in the ruminal fluid. Additionally, relatively high levels of C18:1n9c (and cis-C18:1 isomers), intermediaries of the biohydrogenation of unsaturated FAs [82], were detected among the three dietary groups, although the C18:1n9c concentrations in the HN 6 and LN 6 groups were higher than that in the MN6 group. However, the amount of stearic acid (C18:0), the end product of the biohydrogenation of unsaturated FAs [82], was not influenced by the diet.…”

“…Additionally, relatively high levels of C18:1n9c (and cis-C18:1 isomers), intermediaries of the biohydrogenation of unsaturated FAs [82], were detected among the three dietary groups, although the C18:1n9c concentrations in the HN 6 and LN 6 groups were higher than that in the MN6 group. However, the amount of stearic acid (C18:0), the end product of the biohydrogenation of unsaturated FAs [82], was not influenced by the diet. These results could reflect the incomplete biohydrogenation of unsaturated C18 FAs, which concurs with unsaturated C18 FA (C18:1n9c, C18:2n6, and C18:3n3) concentrations decreasing after incubation for 12 h but remaining stable at 24 and 48 h. However, unsaturated C16:1 and C22:1 were not detected at 48 h, suggesting that the complete biohydrogenation of these unsaturated FAs occurred.…”

Efecto de la altura de pastura sobre el pH ruminal y producción láctea en vacas Holstein, en una pradera de rye grass – ecotipo cajamarquino (Lolium multiflorium) y trébol blanco (Trifolium repens)

“…Además, el pH ruminal guarda una relación con el desarrollo promedio de los microorganismos y esta relación es un componente importante en los modelos desarrollados para estimar la utilización de los nutrientes (Ibrahim et al, 2021;Jameel, 2020). Por esto y por lo dicho anteriormente, se puede decir que el pH guarda una estrecha relación con las características de la pastura.…”

Effects of ca-soap protected vegetables oil in dairy ration on rumen fermentability and in vitro digestibility

“…The decreasing pH value correlates with the protozoa population due to the inhibition of protozoa in entangled feed particles surrounded by fat. The protozoa were decreased by Ca-soap addition due to an effect of defaunation, which made protozoa decay [22]. It also predicted that Ca-soap-protected vegetable oil could partially envelop the membrane cell of protozoa and partially cause depression in the protozoa population [23].…”