The link between supplementary tannin level and conjugated linoleic acid (CLA) formation in ruminants: A meta-analysis

This meta-analysis was conducted to predict and assert a way to discover conjugated linoleic acid (CLA) formation in ruminant-derived products as problem solver of human health issues threated by plant-containing tannins. The objective was to expound, to compare, and to confirm the efficiency of tannins cultivating CLA formation whether using in vitro and/or in vivo study. A database was created using the ruminants with selectively 26 experiments comprising 683 dietary treatments as explained in vitro and in vivo methods that were applied as a statistical SAS 9.4 tool. Basically, increasing level of tannins leaded to an underlying decrease in CLA formation (p<0.001), initially at predicting coefficient determination R2=0.193, R2=0.929, and R2=0.549 for CLA in vitro, in vivo of CLA milk shift, and in vivo of CLA meat precipitation, respectively. In vitro may accurately predict to the in vivo observation. Unfortunately, there were no relationship in vitro towards in vivo observation (R2<0.1). It indicated to be difficult to predict CLA from in vitro to in vivo separately situations. According to all studies, the level of tannin’s utilization for inhibiting biohydrogenation was not exceedingly >50 g/kg DM recommended. Secondly, the in vivo method was more suitable for directly observation that concerned in fatty acid transformation.


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Nowadays, the consumers have been aware to more selectively in their consumption, 38 especially ruminant-derived products such a concerning fat composition in milk and meat. 39 Lourenço, et al [1] reviewed that food for human derived from ruminant product is a high of 40 Saturated Fatty Acid (SFA) and has lower polyunsaturated fatty acid (PUFA) due to detrimental 41 condition of human health, including intensified serum low-density lipoprotein (LDL) questionable. If that was unsuccessful, references were excluded on account of inaccessibility 106 of data. 107 The raw data were strictly screened and accepted in similar calculating unit per parameter, 108 e.g., g/kg FAME (fatty acid methyl ester) and g/kg DM (dry matter) for all FA and tannin level,  In addition, the sources were collected even deriving from individually publication. The  unequal variance among experiments. In a fixed-effects model, a small study was considerably 132 ignored, though, considerable weight was adjusted to a large study (based on number of 133 measurements).

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Outliers were identified by examining mixed procedure with maximum-likelihood (ML).

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For illustrating, it used METHOD=ML; COVTEST; PARMS statement followed by the 136 EQCONS=2 option. An unstructured variance-covariance matrix (type = un) was confirmed as 137 the random part of the model. Also, the comparison between CLA number from milk and meat 138 source could not compare directly. It would be possible comparing total data including covering 139 from in vitro and in vivo observations. Incompleteness of selected data on involving variables, 140 meta analyses were technically performed based on the data available for individual variables.   The effectiveness level of tannins 154 The meta regression strictly between dietary tannins and CLA levels from the in vitro 155 batch culture experiment and the in vivo experiment is presented in Table 3 and Table 4, 156 respectively. The optimum level of tannins for modulating CLA level coming along a nurture rumen fermentation was predicted around 0.1-50 g/kg DM. Regardless of tannin type, the tough 158 natural chemists from tannins provoked the CLA going down gradually (p<0.001) of both 159 studies in in vivo CLA milk shift (Fig 2) with an R 2 of 0.929 and in vivo CLA meat precipitation 160 (Fig 3) with an R 2 of 0.549. However, supplementing a surge of tannin level increased the CLA 161 level in in vitro study, yet, the efficiency of tannin acted dubious. Truly, a rising of CLA trend 162 (p<0.001) was followed by a linear relationship rather than a quadratic response (Fig 4) with 163 an R 2 of 0.193.

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The regression of method application 166 The regression relationships between the in vitro-in vivo of CLA milk form is depicted in

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In this meta-analysis provided underlying prediction and perspective in other tannin ways 215 such a manipulating biohydrogenation to compulsive CLA production massively. As shown in 216 Table 3, dietary tannin affected as statistically regression of the CLA components in milk form 217 (R 2 >0.9), however, not in meat precipitation (R 2 <0.9) without collecting bias data. These results

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were indirectly as same as earlier meta-analysis predicting dietary tannin level on rumen diet 12 .

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Enhancing effort to modulate biohydrogenation is rough and tricky, wherein choose a suitable