Effects Of Fresh Phyllanthus Emblica (Amla) Supplementation On Milk Performance,Ruminal Microbiota,and Milk Fatty Acid Profiles In Lactating Dairy Cows

This study sought to determine the effect of feeding three levels of the novel feedstuff fresh Phyllanthus emblica(amla)fruit on rumen fermentation parameters,microbial population changes,milk production,antioxidant capacity,and milk fatty acid(FA)proportions of lactating dairy cows.Eight ruminally cannulated mid-lactation dairy cows were randomly assigned to two treatment groups in a repeated crossover design.The experiment was conducted over two periods of 42 days each.There was a 14-d adaptation phase followed by the start of period 1.In this period,the first group of 4cows received the control diet,whereas the other group was supplemented with FAF at increasing levels(200,400,600 g/d),sequentially,at 14-d intervals.Each period consisted of a cow as the main plot,with three different amla doses representing subplots.Period 2 began after 14 d of the washout period,and the control and supplemented groups were exchanged.For each sub-period,the first ten days were adjusted for diet adaptation,and the last four days were assigned to sample milk,feed,rumen,blood,and feces.(1)Supplementation of FAF had no effect on feed intake(P= 0.92).However,the apparent digestibility of dry matter(P= 0.05)and organic matter(P= 0.05)of the 400 g/d dose group was lower than that of the cows in the 200 or 600 g/d FAF groups.(2)There was a quadratic effect of FAF(P= 0.02)on milk yield,with the 200 and 400 g/d groups achieving higher milk yields than the 600 g/d groups.The inclusion of 400 g/d FAF in the diet led to greater milk protein yield(P< 0.01)and milk nitrogen efficiency(P< 0.01)compared to cows fed 200g/d FAF.Moreover,the concentration of milk urea nitrogen(MUN)was reduced(P< 0.001)with 200 or 400 g/d FAF supplementation compared with control or 600 g/d FAF.(3)Amla fruit supplementation lowered total saturated fatty acid and the desirable omega-6/omega-3 ratio at 200 or 400 g/d amla fruit dose than controls.In addition,amla fruit increased unsaturated FA(UFA)such as(eicosapentaenoic acid,EPA)and C22:6(docosahexaenoic acid,DHA),and branched-chain FA(BCFA)in a dose-dependent manner at 200 or 400 g/d compared to controls.(4)In addition,amla fruit increased the antioxidant biomarkers in the blood,such as superoxide dismutase(SOD)and albumin.Moreover,the most remarkable improvement of ferric reducingantioxidant power(FRAP)and total antioxidant capacity(TAC)in milk was recorded at 400 g/d amla fruit doses compared to controls.(5)In addition,the rumen protozoa population(P< 0.01)of 400 g/d FAF dose was the lowest compared to other groups.However,total VFA concentrations varied in a quadratic manner(P= 0.04)with increasing FAF doses.While,the rumen ammonia nitrogen(NH3‐N)concentrations were affected(P< 0.001)by FAF,and the lowest concentrations occurred with a 200 g/d dose group and the highest with a 600 g/d dose group.(6)In the control group,Monoglobus and Megasphaera genera were identified as a biomarker species.Whereas in the 200 g/d FAF group Izemoplasmatales,Clostridia＿vadin BB60 and Nocardiopsis were the biomarker genera identified.In the 600 g/d FAF group only the unclassified Propionibaceracea was identified as the biomarker genera.In our study,FAF supplementation affect different parameters in a dose-dependent fashion.The inclusion of 400 g/d FAF dose has benefits in reducing protozoa populations and MUN contents,enhancing milk protein,nitrogen efficiency,antioxidant capacity,as well as improving health desirable milk fatty acid profiles,and flavonoid contents in the milk along with slight improvements in milk yield Therefore,we can conclude that FAF supplementation up to 400 g/d on an as-fed basis or 92.4 g/d as DM basis can be used as an alternative new natural feed source for lactating cows.