Long-term effects of CLA on cows and calves

Does feeding of CLA to dairy cows during the early gestation affect the cow at the beginning of the following lactation period and the newborn calf ?

End of feeding period (182 d) Experimental Setup Depletion time 56 112 168 224 280 336 392 448 190 - 262 days Time [days p.p.] End of feeding period (182 d) 19 - 102 days Exposure time 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 CON CLA50 CLA100

Sampling schedule for blood and milk samples and analyzed parameters   Blood Milk Sampling schedule Cows p.p. (Day 0) p.p. (Day 0 = colostrum) 21 days p.p. Calves p.n. (Day 0) 1 day p.n. (after colostrum) Parameters Fatty acid pattern of erythrocyte lipids Fatty acid pattern of milk fat Stimulation ability of PBMC (MTT- and Alamar Blue assay) Hematology (hematocrit, white blood cell picture) Plasma metabolites (Total bilirubin, total cholesterol, glucose, non-esterified fatty acids, 3-β-hydroxybutyrate, total protein and albumin) Further parameters: Gestation length, calf weight at birth, milk performance until day 21 p.p., live weight gain of calves until day 50 of age

Effects of feeding cows either a control fat supplement (CON) or 50 and 100 g of a CLA containing fat supplement (CLA50 and CLA100, respectively) during the preceding lactation period on milking performance of the first 3 weeks of the following lactation and on performance of calves until day 50 of age   CON CLA50 CLA100 Probabilities Diet Sex Diet x sex Deple-tion time1 Live weight at day 0 Cows Gestation period [d] 283 ±2 286 285 0.394 0.196 0.009 Milk yield [kg/d ] 32.0 ±2.6 32.2 ±0.9 30.6 ±1.1 0.790 0.946 Fat corrected milk [kg/d ] 31.4 ±7.5 34.5 ±4.6 35.5 ±1.7 0.848 0.836 Fat [%] 3.8 ±1.0 4.2 ±0.6 4.7 ±0.3 0.582 0.947 Protein [%] 2.5 ±0.4 3.1 ±0.1 0.293 0.740 Lactose [%] 3.6 ±0.5 3.7 4.5 0.182 0.595 SCC [log10/mL] 1.5 2.3 1.8 0.090 0.986 Calves LW [Day 0, kg] 43.7 ±2.8 45.5 ±2.3 43.3 ±2.2 0.827 0.036 0.336 0.197 LWG [Day 8-50, g/d] 767 ±52 734 ±43 685 ±41 0.469 0.727 0.895 0.088 0.772 SCC=Somatic cell count; LW=live weight; LWG=LW gain

Relationship between birth weight and gestation length [A] and between depletion time and daily live weight gain of calves until 50 days of age [B] [A] [B] 0.9 290 285 0.8 280 Live weight gain [kg/d] 0.7 Gestation period [d] 275 0.6 30 36 42 48 54 182 196 210 224 238 252 266 Live weight at partus [kg] Depletion time [d] [A]: y=262+0.5x (r²=0.391; RSD=4 days) [B]: y=0.075+0.003x (r²=0.291; RSD=0.08 kg/d) CON: male; CON: female; CLA50: male; CLA50: female; CLA100: male; CLA100: female

Total leukocytes [g/L] Effects of feeding cows either a control fat supplement (CON ) or 50 g (CLA50 ) and 100 g (CLA100 ) of a CLA containing fat supplement during the preceding lactation period on total leukocyte counts 2 4 6 8 10 12 Total leukocytes [g/L] 21 1 Days p.p./p.n. Cows Calves b ab ab a a a ab - values with no common letters are significantly different within cattle category (p<0.05, n=4-6)

21 1 Days p.p./p.n. Cows Calves 200 400 600 800 1000 1200 NEFA [µEq/L] Effects of feeding cows either a control fat supplement (CON ) or 50 g (CLA50 ) and 100 g (CLA100 ) of a CLA containing fat supplement during the preceding lactation period on non-esterified fatty acids (NEFA) 21 1 Days p.p./p.n. Cows Calves c b 200 400 600 800 1000 1200 bc ab ab a NEFA [µEq/L] a a a a a a a-c - values with no common letters are significantly different within cattle category (p<0.05, n=4-6)

0.0 0.5 1.0 1.5 2.0 BHB [mMol/L] 21 1 Days p.p./p.n. Cows Calves Effects of feeding cows either a control fat supplement (CON ) or 50 g (CLA50 ) and 100 g (CLA100 ) of a CLA containing fat supplement during the preceding lactation period on β-OH bytyrate (BHB) 0.0 0.5 1.0 1.5 2.0 BHB [mMol/L] 21 1 Days p.p./p.n. Cows Calves a b ab - values with no common letters are significantly different within cattle category (p<0.05, n=4-6)

1 2 3 4 5 6 7 Stimulation index [MTT] 21 Days p.p./p.n. Cows Calves Effects of feeding cows either a control fat supplement (CON ) or 50 g (CLA50 ) and 100 g (CLA100 ) of a CLA containing fat supplement during the preceding lactation period on stimulation ability of mononuklear cells (MTT assay) 1 2 3 4 5 6 7 Stimulation index [MTT] 21 Days p.p./p.n. Cows Calves b b b b b ab a a a a a a ab - values with no common letters are significantly different within cattle category (p<0.05, n=4-6)

SI=6.1-0.002NEFA -6.7BHB+6.3BHB² (r²=0.562, RSD=1.7) Relationship between non-esterified fatty acids (NEFA), 3-β-hydroxybutyrate (BHB) and stimulation index (SI) of cows SI=6.1-0.002NEFA -6.7BHB+6.3BHB² (r²=0.562, RSD=1.7) ○ CON: day 0; ● CON: day 21, □ CLA50: day 0; ■CLA50: day 21; ∆ CLA100- day 0; ▲ CLA100: day 21

CON: day 0; CON: day 21, CLA100: day 0; CLA100: day 21 Relationship between circulating non-esterified fatty acids in cows (NEFA) and sum of saturated [A] and monounsaturated fatty acids fatty acids [B] in milk fat [A] [B] 80 40 76 35 72 fatty acids [%] fatty acids [%] Saturated Monounsaturated 30 68 64 25 60 20 300 600 900 1200 1500 300 600 900 1200 1500 NEFA [µEq/L] NEFA [µEq/L] [A]: y=62.1+0.01x (r²=0.448, RSD=3.9 µEq/L); [B]: y=34.6-0.01)x (r²=0.445, RSD=3.9 µEq/L) CON: day 0; CON: day 21, CLA100: day 0; CLA100: day 21

Fatty acid profiles of erythrocytes of cows( )and their calves ( ) measured directly after partus (Day 0) for Group CON (N=5) and Group CLA100 (N=6) Bars and half-whiskers represent mean values and standard errors (different small letters indicate significant differences between mothers and calves while different capital letters denote significant treatment effects)

Stimulation index [AB] 1 2 3 4 5 6 21 Days p.p./p.n. Cows Calves Effects of feeding cows either a control fat supplement (CON ) or 50 g (CLA50 ) and 100 g (CLA100 ) of a CLA containing fat supplement during the preceding lactation period on stimulation ability of mononuklear cells (Alamar Blue assay) Stimulation index [AB] 1 2 3 4 5 6 21 Days p.p./p.n. Cows Calves ab b a ab - values with no common letters are significantly different within cattle category (p<0.05, n=4-6)