Ebrahimi Mahdi, Rajion Mohamed Ali, Adeyemi Kazeem Dauda, Jafari Saeid, Jahromi Mohammad Faseleh, Oskoueian Ehsan, Meng Goh Yong, Ghaffari Morteza Hosseini
Department of Animal Production University of Ilorin , PMB 1515, Ilorin, Nigeria.
Agriculture Biotechnology Research Institute of Iran (ABRII) , East and North-East Branch, P.O.B. 91735 844, Mashhad, Iran.
J Agric Food Chem. 2017 Feb 1;65(4):737-744. doi: 10.1021/acs.jafc.6b04704. Epub 2017 Jan 18.
Revealing the ruminal fermentation patterns and microbial populations as affected by dietary n-6:n-3 PUFA ratio would be useful for further clarifying the role of the rumen in the lipid metabolism of ruminants. The objective of the present study was to investigate the effects of dietary n-6:n-3 PUFA ratios on fermentation characteristics, fatty acid (FA) profiles, and microbial populations in the rumen of goats. A total of twenty-one goats were randomly assigned to three dietary treatments with different n-6:n-3 PUFA ratios of 2.27:1 (low ratio, LR), 5.01:1 (medium ratio, MR), and 10.38:1 (high ratio, HR). After 100 days of feeding, all goats were slaughtered. Dietary n-6:n-3 PUFA ratios had no effect (P > 0.05) on rumen pH and NHN concentration. Goats fed HR diet had lower (P < 0.05) propionate and total volatile fatty acids and higher (P < 0.05) butyrate compared with those fed the MR and LR diets. The proportion of C18:0 decreased (P < 0.05) as dietary n-6:n-3 PUFA ratios increased. The proportions of C18:1 trans-11, C18:2n-6, cis-9 trans-11 CLA, and C20:4n-6 were greater in the HR goats compared with the MR and LR goats. Lowering dietary n-6:n-3 PUFA ratios enhanced (P < 0.05) the proportion of C18:3n-3 and total n-3 PUFA in the rumen fluid of goats. The populations of R. albus and R. flavefaciens decreased (P < 0.05) as the n-6:n-3 PUFA ratios increased in diet. Diet had no effect (P > 0.05) on the ruminal populations of F. succinogenes, total bacteria, methanogens, total protozoa, Entiodinium, and Holotrich. The population of B. fibrisolvens was lower (P < 0.05) in the LR goats compared with the MR and HR goats. It was concluded that HR would increase the concentration of cis-9 trans-11 CLA and C18:1 trans-11 in the rumen. However, LR whould decrease the B. fibrisolvens population, which is involved in the BH process in the rumen. Further research is needed to evaluate the potential role and contribution of rumen microbiome in the metabolism of FA in the rumen.
揭示瘤胃发酵模式以及受日粮n-6:n-3多不饱和脂肪酸（PUFA）比例影响的微生物种群，将有助于进一步阐明瘤胃在反刍动物脂质代谢中的作用。本研究的目的是调查日粮n-6:n-3 PUFA比例对山羊瘤胃发酵特性、脂肪酸（FA）谱和微生物种群的影响。总共21只山羊被随机分配到三种日粮处理组，其n-6:n-3 PUFA比例不同，分别为2.27:1（低比例，LR）、5.01:1（中等比例，MR）和10.38:1（高比例，HR）。饲养100天后，所有山羊被屠宰。日粮n-6:n-3 PUFA比例对瘤胃pH值和氨氮浓度没有影响（P>0.05）。与饲喂MR和LR日粮的山羊相比，饲喂HR日粮的山羊丙酸和总挥发性脂肪酸含量较低（P<0.05），丁酸含量较高（P<0.05）。随着日粮n-6:n-3 PUFA比例的增加，C18:0的比例降低（P<0.05）。与MR和LR山羊相比，HR山羊中C18:1反式-11、C18:2n-6、顺式-9反式-11共轭亚油酸（CLA）和C20:4n-6的比例更高。降低日粮n-6:n-3 PUFA比例可提高（P<0.05）山羊瘤胃液中C18:3n-3和总n-3 PUFA的比例。随着日粮中n-6:n-3 PUFA比例的增加，白色瘤胃球菌和黄色瘤胃球菌的数量减少（P<0.05）。日粮对琥珀酸丝状杆菌、总细菌、产甲烷菌、总原生动物、艾氏原虫和全毛原虫的瘤胃数量没有影响（P>0.05）。与MR和HR山羊相比，LR山羊中溶纤维丁酸弧菌的数量较低（P<0.05）。得出的结论是，高比例（HR）会增加瘤胃中顺式-9反式-11 CLA和C18:1反式-11的浓度。然而，低比例（LR）会减少参与瘤胃中BH过程的溶纤维丁酸弧菌数量。需要进一步研究来评估瘤胃微生物群在瘤胃脂肪酸代谢中的潜在作用和贡献。
