Inflammatory status and metabolic changes at dry-off in high-yield dairy cows

Figures & data

Table 1. Composition and characteristics of the experimental diets fed during the two experimental phases.

	Phase 1	Phase 2
DFD	−7; 0	10; 34
Diet, % DM
Item
Corn silage	28.50	18.60
Alfalfa hay	16.40	–
Grass hay	23.40	71.40
Concentrate (dry period)	–	10.00
Concentrate (lactation period)	31.70	–
Concentrate composition, %DM
Corn flour	–	40.00
Barley flour	–	1.40
Soybean meal	90.50	13.10
Sunflower meal	–	4.90
Beet pulp	–	16.60
Wheat bran	–	9.80
Beet molasse slops	–	2.60
Potato protein	–	2.20
Hydrogenat palm oil	–	3.30
Limestone	–	1.39
Dicalcium phosphate	–	1.80
Sodium bicarbonate	–	0.98
Magnesium oxide	2.20	0.64
Sodium chloride	1.40	0.32
Supplement^a	5.90	1.07
Chemical composition
NEL, Mcal/kg of DM	1.59	1.45
Crude protein, % DM	14.90	13.60
Starch + sugar, % DM	23.70	16.80
Ether extract, % DM	3.80	1.80
NDF, % DM	39.40	49.30
MP^b, %CP	9.80	9.10
RUP^b, %CP	4.64	4.48

Between dry-off day (−55 days from expected calving) and 10 days from dry-off (DFD) cows received only grass hay.

^a Supplements were composited to provide 150,000 U of vitamin A, 10,000 U of vitamin D, 200 mg of vitamin E, 100 mg of vitamin K, 100 mg of vitamin H1 50 mg of vitamin B1, 0.5 mg of vitamin B12, 500 mg of vitamin PP, 4,000 mg of choline, 350 mg of Mn, 800 mg of Zn, 40 mg of Cu, 20 mg of I, 1 mg of Co, 1 mg Se.

^b Estimate using NRC 2001.

Figure 1. Scheduled time point, expressed as day from dry off (DFD), for dry matter intake and rumination time measurement (DMI-RT), body weight and body condition score determination, white blood cells profiling, whole blood stimulation assay and carrageenan skin test performance (BW-BCS-WBC-WBA-CST), haematic metabolic profile (MP), interferon gamma release assay (IFNG).

Figure 2. Pattern of dry matter intake (a) and rumination time (b) in dairy cows with an average milk production lower (LM; solid line) or higher than 15 L·d⁻¹ (HM; dotted line) in the week prior to dry off. MD is the effect of milk yield at dry off; t is time effect (**p < .01); MD × t is the interaction effect (A/B is p < .01); WFD is weeks from dry off; DRY is dry-off day (−55 days from expected calving).

Figure 3. Time course of packed cell volume (a) and plasma concentrations of NEFA (b), β-hydroxybutyrate (c), l-lactic acid (d), d-lactic acid (e), creatinine (f), urea (g), calcium (h) and magnesium (i) in dairy cows with an average milk production lower (LM; solid line) or higher than 15 L·d⁻¹ (HM; dotted line) in the week prior to dry-off. MD is the effect of milk yield at dry-off; t is time effect (**p < .01; *p < .05; †p < .1); MD × t is the interaction effect (A/B is p < .01); DFD is days from dry-off; DRY is dry-off day (−55 days from expected calving); ^Log indicates data expressed as log-transformed.

Figure 4. Time course of plasma concentrations of phosphorus (a); potassium (b), chlorine (c), zinc (d), γ-glutamyl transferase (e), bilirubin (f), alkaline phosphatase (g), protein (h) and globulin (i) in dairy cows with an average milk production lower (LM; solid line) or higher than 15 L·d⁻¹ (HM; dotted line) in the week prior to dry-off. MD is the effect of milk yield at dry-off; t is time effect (**p < .01; *p < .05; †p < .1); MD × t is the interaction effect; DFD is days from dry-off; DRY is dry-off day (−55 days from expected calving).

Figure 5. Time course of plasma concentrations of haptoglobin (a); ceruloplasmin (b); serum amyloid-α (c), albumin (d), retinol (e), paraoxonase (f), cholesterol (g), interleukin-1 (h) and thiol groups (i) in dairy cows with an average milk production lower (LM; solid line) or higher than 15 L·d⁻¹ (HM; dotted line) in the week prior to dry-off. MD is the effect of milk yield at dry-off; t is time effect (**p < .01; *p < .05; †p < .1); MD × t is the interaction effect; DFD is days from dry-off; DRY is dry-off day (−55 days from expected calving); ^Log indicates data expressed as log-transformed.

Figure 6. Time course of plasma concentrations of ferric reducing antioxidant power (FRAP; a); tocopherol (b), β-carotene (c), oxygen reactive antioxidant power (ORAC; d), advanced oxidation protein product (AOPP; e), nitrite (f), nitrate (g) and nitric oxide (h) in dairy cows with an average milk production lower (LM; solid line) or higher than 15 L·d⁻¹ (HM; dotted line) in the week prior to dry-off. MD is the effect of milk yield at dry-off; t is the time effect (**p < .01; *p < .05; †p < .1); MD × t is the interaction effect (a/b is p < .05; a/b is p < .1); DFD is days from dry-off; DRY is dry-off day (−55 days from expected calving); ^Log indicates data expressed as log-transformed.

Table 2. White blood cells profile in dairy cows with an average milk production lower (LM) or higher (HM) than 15 L·d⁻¹ in the week prior to dry-off.

Item, unit	MD^a	Days from dry-off			SE^b	p Value
		−7	7	34		MD^a	t^c	MD × t^d
White blood  cells, K·µL^−1	LM	6.84	6.52	6.54	0.73	.99	.03	.21
	HM	6.91	6.11	6.92	0.79
			*
Neutrophils,  K·µL^−1	LM	3.45	3.00	3.32	0.30	.65	<.01	.79
	HM	3.73	3.05	3.50	0.33
			**
Monocytes,  K·µL^−1	LM	0.55	0.41	0.55	0.04	.88	<.01	.78
	HM	0.58	0.43	0.53	0.04
			**
Eosinophils,  K·µL^−1	LM	0.19	0.45	0.23	0.11	.32	.04	.82
	HM	0.03	0.31	0.15	0.12
			*
Red blood  cells, K·µL^−1	LM	6.59	6.68	6.36	0.18	.34	.02	.65
	HM	6.26	6.59	6.10	0.20
Haemoglobin,  g·dL^−1	LM	10.70	11.20	10.70	0.38	.39	<.01	.85
	HM	10.30	10.80	10.10	0.41
			**
Haematocrit, %	LM	31.30	32.10	31.10	1.23	.57	.02	.38
	HM	30.20	32.20	29.30	1.33
			*
Platelets, K·µL^−1	LM	325.70	318.40	279.10	48.60	.71	.17	.08
	HM	334.00	285.80	348.50	52.50
MPV^e, K·µL^−1	LM	7.16	7.10	7.58	0.41	.06	.44	.29
	HM	5.84	6.69	6.24	0.52

^a Effect of milk yield at dry-off.

^b Standard error.

^c Time effect (comparisons are made with respect to −7 days from dry-off value: *p < .05; **p < .01).

^d Milk yield at dry-off × time interaction effect.

^e Mean platelet volume.

Table 3. Fold changes of cytokines after a whole blood stimulation assay with a low (L) or high (H) dose of bacterial lipopolysaccharides (LPS) in dairy cows with an average milk production lower (LM) or higher (HM) than 15 L·d⁻¹ in the week prior to dry-off.

Item	D^b	MD^a	Days from dry-off			SE^c	Effect	p Value
			−7	7	34
IL-1B^g	L	LM	3.74	7.79	8.59	6.54	MD^a	.61
		HM	4.54	9.20	10.84	7.06	t^d	<.01
	H	LM	15.66	25.38	25.61	6.54	D^b	<.01
		HM	15.96	25.67	35.41	7.06	MD × t^e	.89
	Tot	LM	9.70	16.58	17.10	5.45	MD × t×D^f	.77
		HM	10.25	17.44	23.13	5.89
				**	**
IL-6	L	LM	1.42	1.73	1.36	0.21	MD^a	.51
		HM	1.46	1.56	1.41	0.23	t^d	.06
	H	LM	2.21	2.40	2.00	0.21	D^b	<.01
		HM	1.73	1.93	1.74	0.23	MD × t^e	.75
	Tot	LM	1.81	2.07	1.68	0.18	MD × t×D^f	.75
		HM	1.60	1.74	1.58	0.19
				+

Values are expressed with respect to baseline (unstimulated sample).

^a Milk yield at dry-off effect.

^b Dose effect: L is the low dose (0.01 µg LPS/mL whole blood); H is the high dose (5 µg LPS/mL whole blood); Tot is the total effect of LPS stimulation.

^c Standard error.

^d Time effect (comparisons are made with respect to −7 days from dry-off value: + is P < .1; *p < .05; **p < .01).

^e Milk yield at dry-off × time interaction effect.

^f Milk yield at dry-off × time × dose interaction effect.

^g Interleukin-1, beta.

Table 4. Fold changes of glucose and metabolites thereof after a whole blood stimulation assay with a low (L) or high (H) dose of bacterial lipopolysaccharides (LPS) in dairy cows with an average milk production lower (LM) or higher (HM) than 15 L·d⁻¹ in the week prior to dry-off.

Item	D^b	MD^a	Days from dry-off			SE^c	Effect	p Value
			−7	7	34
Glucose	L	LM	0.950	0.970	0.960	0.022	MD^a	.170
		HM	0.980	0.950	0.990	0.023	t^d	.720
	H	LM	0.920	0.930	0.910	0.022	D^b	.060
		HM	0.940	0.950	0.980	0.023	MD × t^e	.250
	Tot	LM	0.940	0.950	0.940	0.016	MD × t×D^f	.850
		HM	0.960	0.950	0.980	0.017
d-Lactic acid	L	LM	1.000	1.040	1.050	0.032	MD^a	.570
		HM	1.040	1.020	1.030	0.034	t^d	.320
	H	LM	1.010	1.020	1.080	0.032	D^b	.150
		HM	1.070	1.070	1.080	0.034	MD × t^e	.330
	Tot	LM	1.010	1.030	1.070	0.025	MD × t×D^f	.790
		HM	1.060	1.040	1.060	0.027
l-Lactic acid	L	LM	1.030	1.010	1.040	0.015	MD^a	.620
		HM	1.030	1.030	1.040	0.017	t^d	.050
	H	LM	1.050	1.020	1.070	0.015	D^b	.030
		HM	1.060	1.050	1.060	0.017	MD × t^e	.270
	Tot	LM	1.040	1.020	1.060	0.012	MD × t×D^f	.970
		HM	1.050	1.040	1.050	0.013

Values are expressed with respect to baseline (unstimulated sample).

^a Milk yield at dry-off effect.

^b Dose effect: L is the low dose (0.01 µg LPS/mL whole blood); H is the high dose (5 µg LPS/mL whole blood); Tot is the total effect of LPS stimulation.

^c Standard error.

^d Time effect (comparisons are made with respect to −7 days from dry-off value: + is p < .1; *p < .05; **p < .01).

^e Milk yield at dry-off × time interaction effect.

^f Milk yield at dry-off × time × dose interaction effect.

Table 5. Fold changes of nitrite, nitrate and nitric oxides after a whole blood stimulation assay with a low (L) or high (H) dose of bacterial lipopolysaccharides (LPS) in dairy cows with an average milk production lower (LM) or higher (HM) than 15 L·d⁻¹ in the week prior to dry-off.

Item	D^b	MD^a	Days from dry off			SE^c	Effect	p Value
			−7	7	34
Nitric oxide	L	LM	1.000	1.000	1.000	0.075	MD^a	.510
		HM	0.880	1.030	1.020	0.081	t^d	.420
	H	LM	1.160	1.160	1.040	0.075	D^b	.080
		HM	0.970	1.010	1.090	0.081	MD × t^e	.040
	Tot	LM	1.080a	1.080	1.020	0.061	MD × t×D^f	.510
		HM	0.930b	1.020	1.060	0.066
Nitrite	L	LM	0.980	0.980	1.030	0.069	MD^a	.600
		HM	0.960	0.880	1.190	0.074	t^d	.020
	H	LM	1.000	1.020	1.130	0.069	D^b	.810
		HM	1.030	0.900	1.010	0.074	MD × t^e	.340
	Tot	LM	0.990	1.000	1.080	0.053	MD × t×D^f	.600
		HM	0.990	0.890	1.100	0.057
					*
Nitrate	L	LM	1.000	1.000	1.000	0.126	MD^a	.480
		HM	0.870	1.080	0.960	0.136	t^d	.470
	H	LM	1.230	1.300	1.070	0.126	D^b	.110
		HM	0.960	1.040	1.120	0.136	MD × t^e	.110
	Tot	LM	1.110	1.150	1.030	0.098	MD × t×D^f	.480
		HM	0.910	1.060	1.040	0.105

Values are expressed with respect to baseline (unstimulated sample).

^a Milk yield at dry-off effect.

^b Dose effect: L is the low dose (0.01 µg LPS/mL whole blood); H is the high dose (5 µg LPS/mL whole blood); Tot is the total effect of LPS stimulation.

^c Standard error.

^d Time effect (comparisons are made with respect to −7 days from dry-off value: + is p < .1; *p < .05; **p < .01).

^e Milk yield at dry-off × time interaction effect (a/b is p < .1).

^f Milk yield at dry-off × time × dose interaction effect.