Milk yield and quality of Original Brown cattle reared in Italian alpine region

Figures & data

Figure 1. Distribution of the 23 farms involved in the study in the province of Bolzano.

Figure 2. Distribution of calvings of primiparous (dashed bar, n = 154) and multiparous (solid bar, n = 366) cows across calving seasons.

Table 1. Descriptive statistics of milk yield, composition, somatic cell score, coagulation properties, casein fractions, minerals and fatty acid (FA) composition of Original Brown cows.

Trait^a	n	Mean	CV, %	Minimum	Maximum
Milk yield, kg/d	4007	18.07	29.8	2.90	35.00
Milk composition, %
Fat	3948	4.03	17.8	1.24	7.02
Protein	4001	3.40	10.7	2.26	4.62
Casein	4005	2.68	10.9	1.79	3.65
Lactose	3986	4.83	4.6	3.80	5.59
Somatic cell score, units	4020	3.19	62.5	−2.06	9.29
Coagulation properties
RCT, min	3230	19.78	20.7	5.65	29.00
a30, mm	2797	19.34	57.7	0.05	55.30
k20, min	3292	5.45	23.2	2.07	10.98
Casein fractions, % crude protein
α-casein	3473	0.44	7.6	0.34	0.55
β-casein	3430	0.29	14.3	0.17	0.41
κ-casein	3425	0.18	20.6	0.08	0.29
Minerals, mg/kg
Ca	2294	1431.80	10.7	963.84	1903.02
K	2308	1543.54	8.6	874.31	2066.54
P	2299	1010.95	10.6	703.52	1329.33
Mg	2009	145.34	15.7	62.24	193.50
Na	2310	397.63	14.3	135.13	603.44
Groups of FA, g/100 g total FA
Monounsaturated FA	3435	25.60	17.5	12.20	40.16
Polyunsaturated FA	3431	3.27	20.4	1.21	5.50
Saturated FA	3460	66.56	8.0	47.31	81.09
Unsaturated FA	3447	31.44	15.3	17.50	46.73
transFA	3396	1.88	38.8	0.01	4.22
Short chain FA	3458	11.29	16.4	5.53	17.05
Medium chain FA	3456	40.11	18.8	15.81	64.92
Long chain FA	3446	34.18	17.0	16.85	52.78
Individual FA, g/100 g total FA
C14:0	3445	11.41	13.9	6.24	16.36
C16:0	3462	29.76	12.7	18.18	40.72
C18:0	3465	10.17	22.4	3.91	16.94
C18:1	3436	22.09	20.4	7.65	36.84

CV: coefficient of variation.

^aRCT: rennet coagulation time; a₃₀: curd firmness 30 min after enzyme addition to milk; k₂₀: curd-firming time.

Table 2. Pearson correlations between milk yield (kg/d), composition traits, coagulation parameters, casein fractions (% crude protein), and minerals (mg/kg).

Trait^1	Milk yield	Fat, %	Protein, %	Casein, %	Lactose, %	SCS	RCT	a30	k20	α-casein	β-casein	κ-casein	Ca	K	P	Mg
Fat, %	−0.22
Protein, %	−0.4	0.3
Casein, %	−0.38	0.32	0.98
Lactose, %	0.23	−0.11	−0.09	−0.02^a
SCS	−0.24	0.14	0.08	0.03^a	−0.41
RCT	−0.06^a	0.08	0.05^a	0.05^a	−0.22	0.33
a30	−0.05^a	0.08	0.16	0.16	0.16	−0.22	−0.72
k20	0.17	−0.25	−0.55	−0.56	−0.17	0.13	0.38	−0.58
α-casein	0.21	0.16	−0.08	−0.07^a	−0.06^a	0.12	0.1	−0.06^a	0.16
β-casein	0.01^a	−0.02^a	0.01^a	0.01^a	0.07	−0.14	0.09	−0.19	0.08	−0.52
κ-casein	0.02^a	0.04^a	−0.17	−0.16	−0.11	0.08	0.22	−0.02^a	−0.15	−0.2	0.00^a
Ca	−0.23	0.23	0.28	0.28	0.01^a	−0.03^a	−0.26	0.33	−0.39	−0.09	−0.16	−0.25
K	0.01^a	−0.31	−0.25	−0.28	−0.17	0.07^a	−0.09	0.03^a	0.04^a	−0.04^a	−0.05^a	0.16	0.22
P	−0.2	0.14	0.39	0.37	0.17	−0.11	−0.36	0.33	−0.37	−0.36	0.21	−0.23	0.47	0.22
Mg	−0.13	0.12	0.24	0.22	−0.04^a	−0.01^a	−0.27	0.3	−0.4	0.1	−0.11	−0.39	0.54	0.13	0.35
Na	−0.22	−0.23	0.08	0.01^a	−0.83	0.4	0.25	−0.21	0.17	−0.07^a	−0.09	0.07^a	0.05^a	0.33	−0.27	0.03^a

¹SCS: somatic cell score; RCT: rennet coagulation time (min); a₃₀: curd firmness 30 min after enzyme addition to milk (mm); k₂₀: curd-firming time (min). ^aCorrelations not different from zero (p > .05).

Table 3. Pearson correlations between individual and groups of milk fatty acids (g/100 g total FA) with milk yield, composition traits, coagulation parameters, casein fractions (% crude protein), and minerals (mg/kg).

Trait	MUFA	PUFA	SFA	UFA	transFA	SCFA	MCFA	LCFA	C14:0	C16:0	C18:0	C18:1
Milk yield, kg/d	−0.1	−0.01^a	0.07	−0.07	0.09	0.2	−0.14	−0.02^a	0.1	−0.05^a	0.09	−0.1
Fat, %	0.01^a	−0.17	0.02^a	−0.01^a	−0.13	0.13	0.09	0.04^a	−0.26	−0.02^a	0.04^a	0.07
Protein, %	−0.02^a	−0.07	−0.00^a	0.00^a	−0.4	0.11	0.17	−0.09	−0.02^a	−0.03^a	−0.17	−0.04^a
Casein, %	−0.02^a	−0.07	−0.00^a	−0.01^a	−0.35	0.14	0.14	−0.08	−0.02^a	−0.04^a	−0.18	−0.04^a
Lactose, %	−0.02	0.07	0.09	−0.11	0.27	0.08	−0.29	0.01^a	0.16	0.07	0.08	−0.07
SCS	−0.02^a	−0.04^a	0.06^a	−0.03^a	−0.1	−0.17	0.17	−0.09	0.02^a	0.14	−0.04^a	0.00^a
RCT	−0.12	−0.07^a	0.01^a	−0.03^a	−0.02^a	−0.03^a	0.11	−0.1	0.03^a	0.07^a	−0.09	−0.11
a30	0.25	0.14	0.13	0.00^a	0.07^a	−0.23	0.09	0.06^a	0.01^a	0.02^a	0.28	0.22
k20	−0.2	−0.1	−0.12	0.00^a	−0.01^a	0.13	−0.14	−0.05^a	−0.05^a	0.03^a	−0.22	−0.16
α-casein	−0.4	−0.36	0.28	−0.32	−0.2	0.31	0.15	−0.3	0.18	0.22	−0.08	−0.34
β-casein	−0.00^a	0.09	−0.33	0.21	0.03^a	0.22	−0.31	0.15	−0.18	−0.28	−0.17	−0.01^a
κ-casein	0.29	0.32	−0.00^a	0.15	0.32	−0.32	0.15	0.17	−0.06^a	−0.08	0.43	0.31
Ca	0.41	0.22	−0.27	0.3	−0.03^a	−0.23	−0.01^a	0.35	−0.36	−0.19	0.2	0.35
K	0.23	0.35	−0.23	0.19	0.1	−0.08^a	−0.03^a	0.22	−0.19	−0.18	0.07^a	0.24
P	0.27	0.21	−0.19	0.18	−0.04^a	0.11	−0.02^a	0.23	−0.26	−0.19	0.05^a	0.2
Mg	0.15	0.02^a	0.04^a	0.01^a	−0.00^a	−0.13	0.13	0.08^a	−0.04^a	−0.06^a	0.11	0.1
Na	0.02^a	0.09^a	−0.14	0.13	−0.3	−0.24	0.11	−0.03	−0.02^a	−0.06^a	−0.18	0.02^a
MUFA		0.75	−0.55	0.8	0.49	−0.52	−0.19	0.84	−0.63	−0.6	0.65	0.97
PUFA			−0.55	0.67	0.48	−0.29	−0.32	0.68	−0.44	−0.58	0.49	0.7
SFA				−0.88	−0.14	−0.06^a	0.61	−0.81	0.83	0.86	−0.17	−0.55
UFA					0.27	−0.2	−0.44	0.91	−0.82	−0.83	0.43	0.79
trans FA						−0.44	−0.18	0.41	−0.16	−0.22	0.52	0.48
SCFA							−0.29	−0.24	0.01^a	−0.03^a	−0.61	−0.47
MCFA								−0.42	0.4	0.52	0.11	−0.22
LCFA									−0.84	−0.83	0.58	0.84
C14:0										0.81	−0.38	−0.68
C16:0											−0.38	−0.63
C18:0												0.64

SCS: somatic cell score; RCT: rennet coagulation time (min); a₃₀: curd firmness 30 min after enzyme addition to milk (mm); k₂₀: curd-firming time (min); MUFA: monounsaturated fatty acids; PUFA: polyunsaturated fatty acids; SFA: saturated fatty acids; UFA: unsaturated fatty acids; transFA: trans fatty acids; SCFA: short-chain fatty acids; MCFA: medium-chain fatty acids; LCFA: long-chain fatty acids; ^aCorrelations not different from zero (p > .05).

Table 4. Least squares means of milk yield, composition, somatic cell score, coagulation properties, casein fractions, minerals and fatty acid (FA) composition across parities.

Trait	Parity 1	Parity 2	Parity 3	Parity 4	Parity ≥ 5
Milk yield, kg/d	16.58^c	17.47^b	18.57^a	18.56^a	18.27^a
Milk composition, %
Fat	4.11^ab	4.15^a	4.04^c	4.03^bc	3.98^c
Protein	3.44^b	3.48^a	3.47^a	3.43^bc	3.40^c
Casein	2.72^ab	2.74^a	2.74^a	2.70^b	2.67^c
Lactose	4.91^a	4.81^b	4.81^b	4.78^c	4.76^c
SCS, units	2.37^e	2.97^d	3.30^c	3.47^b	3.67^a
Coagulation properties
RCT, min	19.20^b	20.01^a	19.48^b	20.20^a	20.16^a
a30, mm	27.74^a	26.61^b	27.32^ab	25.02^c	24.92^c
k20, min	4.89^c	4.99^c	4.97^c	5.19^b	5.37^a
Protein fractions, % of protein
α-casein	0.43^c	0.44^b	0.44^b	0.44^a	0.44^a
β-casein	0.30^a	0.30^ab	0.30^bc	0.29^d	0.29^cd
κ-casein	0.18^a	0.18^a	0.17^b	0.17^b	0.17^c
Minerals, mg/kg
Ca	1469.77^a	1444.30^b	1436.07^b	1428.33^b	1411.26^c
K	1548.07^a	1527.80^b	1530.02^b	1528.34^b	1538.14^ab
P	1059.90^a	1019.66^b	1009.62^c	996.08^d	1003.12^cd
Mg	152.29^a	149.90^bc	150.64^b	148.70^c	148.08^c
Na	368.98^d	397.79^c	402.60^c	409.57^b	417.14^a
Groups of FA, g/100 g total FA
Monounsaturated FA	27.23^a	25.60^b	25.34^bc	25.17^cd	24.92^d
Polyunsaturated FA	3.47^a	3.26^b	3.23^bc	3.20^c	3.19^c
Saturated FA	64.98^b	66.22^a	66.32^a	66.15^a	66.20^a
Unsaturated FA	32.93^a	31.75^b	31.77^b	31.88^b	31.79^b
transFA	2.09^a	1.81^b	1.72^c	1.69^cd	1.63^d
Short chain FA	11.30^b	11.37^b	11.44^b	11.37^b	11.63^a
Medium chain FA	38.95^b	39.59^a	38.58^b	38.57^b	38.94^ab
Long chain FA	36.23^a	34.18^b	33.98^b	34.06^b	34.11^b
Individual FA, g/100 g total FA
C14:0	10.89^b	11.33^a	11.43^a	11.40^a	11.39^a
C16:0	28.83^b	29.58^a	29.48^a	29.45^a	29.42^a
C18:0	10.56^a	10.11^b	9.86^c	9.89^c	9.82^c
C18:1	23.48^a	22.05^b	21.78^bc	21.58^cd	21.23^d

Least squares means with different superscript letters within a row are significantly different (p < .05).

RCT: rennet coagulation time; a₃₀: curd firmness 30 min after enzyme addition to milk; k₂₀: curd-firming time.

Figure 3. Least squares means of (a) fat, protein and casein content, and (b) lactose content and somatic cell score (SCS) throughout lactation.

Figure 4. Least squares means of (a) rennet coagulation time (RCT), curd firmness 30 min after enzyme addition to milk (a₃₀) and curd-firming time (k₂₀), and (b) α-casein, β-casein and κ-casein fractions throughout lactation.

Figure 5. Least squares means of milk (a) Ca, K and P, and (b) Mg and Na throughout lactation.

Figure 6. Least squares means of (a) monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), (b) saturated (SFA) and trans fatty acids (trans FA), (c) short-chain (SCFA), medium-chain (MCFA) and long-chain fatty acids (LCFA), and (d) individual fatty acids throughout lactation.