Table 5.
Effect of maternal body condition (thin or fat) and gestation feed level (restricted: 1·8 kg/d; control: 2·5 kg/d; or high feed level: 3·5 kg/d) on fatty acid composition of milk at day 21 of lactation
(Adjusted mean values with their pooled standard errors)
| Thin | Fat | P† | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Treatment | 1·8 kg | 2·5 kg | 3·5 kg | 1·8 kg | 2·5 kg | 3·5 kg | sem | Body condition | Feed level |
| n | 9 | 14 | 14 | 12 | 15 | 13 | |||
| Fatty acid composition (g/100 g of FAME) of milk day 21* | |||||||||
| C4 : 0 | 0·11 | 0·06 | 0·05 | 0·05 | 0·08 | 0·02 | 0·041 | 0·427 | 0·395 |
| C10 : 0 | 0·18 | 0·15 | 0·14 | 0·17 | 0·12 | 0·10 | 0·020 | 0·035 | 0·005 |
| C12 : 0 | 0·26 | 0·22 | 0·22 | 0·25 | 0·18 | 0·17 | 0·023 | 0·010 | 0·006 |
| C14 : 0 | 3·41 | 3·04 | 3·13 | 3·19 | 2·69 | 2·42 | 0·216 | 0·004 | 0·014 |
| C14 : 1 c9 | 0·32 | 0·22 | 0·23 | 0·23 | 0·17 | 0·18 | 0·033 | 0·005 | 0·018 |
| C15 : 0 | 0·100 | 0·102 | 0·092 | 0·097 | 0·080 | 0·071 | 0·0095 | 0·014 | 0·099 |
| C16 : 0 | 32·40 | 31·12 | 31·42 | 31·36 | 29·47 | 27·08 | 1·461 | 0·018 | 0·113 |
| C16 : 1 c9 | 11·97 | 9·44 | 9·36 | 9·47 | 8·37 | 7·84 | 1·018 | 0·023 | 0·052 |
| C17 : 0 | 0·20 | 0·24 | 0·23 | 0·21 | 0·23 | 0·21 | 0·018 | 0·388 | 0·144 |
| C17 : 1 c7 | 0·31 | 0·34 | 0·31 | 0·29 | 0·31 | 0·24 | 0·030 | 0·050 | 0·187 |
| C17 : 1 c10 | 0·33 | 0·35 | 0·47 | 0·43 | 0·35 | 0·28 | 0·104 | 0·584 | 0·886 |
| C18 : 0 | 3·06 | 3·91 | 3·82 | 3·57 | 4·02 | 4·49 | 0·295 | 0·045 | 0·006 |
| C18 : 1 total | 25·4 | 28·6 | 30·0 | 27·9 | 30·3 | 33·9 | 1·85 | 0·020 | 0·015 |
| C18 : 2 t9, t12 n-6 | 1·63 | 1·79 | 1·73 | 1·73 | 1·67 | 1·80 | 0·097 | 0·888 | 0·656 |
| C18 : 2n-6 | 16·4 | 16·1 | 15·8 | 16·8 | 17·5 | 16·5 | 0·90 | 0·159 | 0·637 |
| C18 : 3n-6 | 0·06 | 0·09 | 0·07 | 0·08 | 0·08 | 0·12 | 0·024 | 0·281 | 0·571 |
| C18 : 3n-3 | 1·62 | 1·55 | 1·55 | 1·65 | 1·71 | 1·62 | 0·091 | 0·131 | 0·784 |
| c9, t11 CLA | 0·05 | 0·06 | 0·05 | 0·07 | 0·07 | 0·07 | 0·009 | 0·077 | 0·680 |
| C20 : 2 | 0·19 | 0·27 | 0·27 | 0·21 | 0·26 | 0·38 | 0·045 | 0·200 | 0·010 |
| C20 : 3n-6 | 0·21 | 0·30 | 0·27 | 0·32 | 0·33 | 0·38 | 0·044 | 0·009 | 0·286 |
| C20 : 4n-6 | 0·38 | 0·51 | 0·39 | 0·45 | 0·47 | 0·50 | 0·048 | 0·229 | 0·181 |
| C22 : 5n-3 | 0·13 | 0·15 | 0·15 | 0·13 | 0·16 | 0·15 | 0·019 | 0·627 | 0·366 |
| C22 : 6n-3 | 0·011a | 0·037b | 0·021a,b | 0·026a,b | 0·024a,b | 0·028a,b | 0·0075 | 0·551 | 0·185 |
| C24 : 0 | 0·06 | 0·05 | 0·05 | 0·06 | 0·08 | 0·05 | 0·021 | 0·733 | 0·609 |
| Total unsaturated | 59·19 | 60·11 | 59·85 | 60·00 | 61·92 | 64·09 | 1·433 | 0·017 | 0·154 |
| Total saturated | 39·85 | 38·96 | 39·22 | 39·02 | 37·02 | 34·69 | 1·475 | 0·014 | 0·146 |
| Total n-3 | 1·81 | 1·83 | 1·78 | 1·90 | 1·97 | 1·87 | 0·106 | 0·141 | 0·697 |
| Total n-6 | 18·70 | 18·80 | 18·27 | 19·40 | 20·09 | 19·25 | 0·958 | 0·120 | 0·669 |
| Ratio unsaturated:saturated | 1·52 | 1·58 | 1·56 | 1·58 | 1·71 | 1·89 | 0·113 | 0·022 | 0·192 |
| Ratio n-6:n-3 | 10·35 | 10·35 | 10·28 | 10·24 | 10·26 | 10·33 | 0·193 | 0·708 | 0·992 |
FAME, fatty acid methyl esters; CLA, conjugated linoleic acid.
a,b Mean values within a row with unlike superscript letters were significantly different (P < 0·05) (Tukey–Kramer adjusted).
* Only fatty acids of >0·05 g/100 g of FAME are shown (C6 : 0, C8 : 0, C9 : 0, C10 : 1, C14 : 1 t9, Iso C16 : 0, C16 : 1 t9, C20 : 0, C20 : 1, C20 : 3n-3, C20 : 5n-3, C21 : 5, C24 : 0 have been excluded for values >0·05 g/100 g of FAME).
† There was a body condition × feed level interaction for C20 : 3n-3 (P = 0·05) and a trend on C6 : 0 (P = 0·06), C9 : 0 (P = 0·09) and C22 : 6n-6 (P = 0·09).