Milk production of Holstein-Friesian, Jersey and crossbred cows milked once-a-day or twice-a-day in New Zealand

Figures & data

Table 1. Number of herd-test records, number of lactations and cows per milking frequency and breed group.

	Once-a-day				Twice-a-day
	Holstein-Friesian	F × J^1	Jersey	Total	Holstein-Friesian	F × J^1	Jersey	Total
Herd-test records	11,525	44,005	33,767	89,297	38,081	72,531	23,240	133,852
Lactations	4116	14,813	9881	28,810	11,632	22,215	6298	40,145
Cows	3234	11,795	7348	22,377	8614	15,925	4329	28,868

¹Holstein-Friesian × Jersey crossbred cows.

Table 2. Least square means and standard errors of regression coefficients of the lactation curve for milk yield modelled with a fifth-order Legendre polynomial fitted to Holstein-Friesian (F), Jersey (J) and first F × J crossbred cows of different lactation number and milking frequency (MF).

MF^1	Breed	Lactation number	α0	α1	α2	α3	α4	α5
OAD			11.16^a ± 0.09	−5.08^a ± 0.05	−0.55^a ± 0.04	0.57^a ± 0.04	−0.24^a ± 0.04	−0.03^a ± 0.04
TAD			13.65^b ± 0.08	−6.32^b ± 0.05	−0.10^b ± 0.04	0.50^a ± 0.04	−0.58^b ± 0.04	0.45^b ± 0.04
OAD	F		13.37^a ± 0.16	−5.91^a ± 0.09	−0.47^a ± 0.08	0.66^a ± 0.06	−0.45^a ± 0.06	0.13^a ± 0.06
TAD	F		17.69^b ± 0.11	−8.17^b ± 0.06	0.03^b ± 0.05	0.70^a ± 0.04	−0.80^b ± 0.04	0.83^b ± 0.04
OAD	F × J		12.61^a ± 0.14	−5.61^a ± 0.10	−0.62^a ± 0.08	0.57^a ± 0.07	−0.26^a ± 0.07	0.22^a ± 0.08
TAD	F × J		15.65^b ± 0.13	−7.13^b ± 0.10	−0.22^b ± 0.08	0.67^a ± 0.07	−0.60^b ± 0.07	0.56^b ± 0.08
OAD	J		11.13^a ± 0.08	−5.10^a ± 0.05	−0.55^a ± 0.04	0.55^a ± 0.04	−0.21^a ± 0.04	−0.03^a ± 0.04
TAD	J		13.51^b ± 0.09	−6.14^b ± 0.06	−0.33^b ± 0.05	0.51^a ± 0.05	−0.48^b ± 0.05	0.39^b ± 0.05
OAD		1	8.25^a ± 0.09	−3.51^a ± 0.06	−0.78^a ± 0.05	0.39^a ± 0.04	0.01^a ± 0.04	−0.43^a ± 0.04
TAD		1	10.45^b ± 0.09	−4.72^b ± 0.06	−0.22^b ± 0.05	0.33^a ± 0.04	−0.43^b ± 0.04	0.11^b ± 0.04
OAD		2	10.70^a ± 0.09	−4.81^a ± 0.06	−0.58^a ± 0.04	0.53^a ± 0.04	−0.23^a ± 0.04	−0.05^a ± 0.04
TAD		2	12.96^b ± 0.09	−5.91^b ± 0.05	−0.11^b ± 0.04	0.37^a ± 0.04	−0.52^b ± 0.04	0.44^b ± 0.04
OAD		3	11.83^a ± 0.09	−5.47^a ± 0.06	−0.47^a ± 0.05	0.60^a ± 0.04	−0.29^a ± 0.04	0.08^a ± 0.04
TAD		3	14.44^b ± 0.09	−6.68^b ± 0.06	−0.03^b ± 0.05	0.52^a ± 0.04	−0.66^b ± 0.04	0.49^b ± 0.04
OAD		4	12.39^a ± 0.09	−5.73^a ± 0.06	−0.45^a ± 0.05	0.64^a ± 0.04	−0.33^a ± 0.04	0.13^a ± 0.04
TAD		4	15.08^b ± 0.09	−7.08^b ± 0.06	−0.06^b ± 0.05	0.65^a ± 0.04	−0.66^b ± 0.04	0.59^b ± 0.04
OAD		5	12.63^a ± 0.09	−5.87^a ± 0.06	−0.48^a ± 0.05	0.71^a ± 0.04	−0.33^a ± 0.04	0.14^a ± 0.04
TAD		5	15.29^b ± 0.09	−7.20^b ± 0.06	−0.07^b ± 0.05	0.61^a ± 0.04	−0.62^a ± 0.04	0.64^b ± 0.04

¹MF OAD, milking once-daily; MF TAD, milking twice-daily.

^a,bLeast square means with different superscripts are significantly different between milking frequencies with breed-type or within lactation number (P < 0.05).

Table 3. Least square means and standard errors (x10²) of regression coefficients of the lactation curve for fat yield modelled with a fifth-order Legendre polynomial fitted to Holstein-Friesian (F), Jersey (J) and first F × J crossbred cows of different lactation number and milking frequency (MF).

MF^1	Breed	Lactation number	α0	α1	α2	α3	α4	α5
OAD			65.13^a ± 0.40	−16.83^a ± 0.24	−2.97^a ± 0.19	1.76^a ± 0.17	−2.01^a ± 0.15	−0.47^a ± 0.16
TAD			76.76^b ± 0.39	−22.09^b ± 0.25	−1.24^b ± 0.20	1.59^a ± 0.17	−3.66^b ± 0.16	1.23^b ± 0.17
OAD	F		65.16^a ± 0.67	−17.43^a ± 0.40	−1.87^a ± 0.31	1.57^a ± 0.27	−2.26^a ± 0.27	−0.24^a ± 0.23
TAD	F		79.74^b ± 0.45	−24.97^b ± 0.26	0.82^b ± 0.20	0.68^a ± 0.17	−3.69^b ± 0.17	3.63^b ± 0.14
OAD	F × J		67.34^a ± 0.68	−18.07ª ± 0.48	−2.55^a ± 0.39	1.23^a ± 0.34	−2.08^a ± 0.33	0.36ª ± 0.36
TAD	F × J		77.99^b ± 0.68	−22.79^b ± 0.48	−0.89^a ± 0.40	1.21^a ± 0.35	−3.20^a ± 0.34	1.46^a ± 0.37
OAD	J		65.34^a ± 0.43	−17.06^a ± 0.28	−3.06^a ± 0.23	1.74^a ± 0.20	−1.96^a ± 0.19	−0.42^a ± 0.19
TAD	J		77.31^b ± 0.50	−21.76^b ± 0.34	−2.02^a ± 0.27	1.58^a ± 0.24	−3.44^b ± 0.23	1.19^b ± 0.23
OAD		1	50.82^a ± 0.42	−11.26^a ± 0.26	−2.86^a ± 0.21	1.13^a ± 0.18	−1.12^a ± 0.17	−1.98^a ± 0.18
TAD		1	62.08^b ± 0.40	−16.69^b ± 0.26	−0.60^b ± 0.21	0.94^a ± 0.19	−3.12^b ± 0.18	0.27^b ± 0.19
OAD		2	62.97^a ± 0.41	−15.75^a ± 0.25	−3.02^a ± 0.21	1.60^a ± 0.18	−2.02^a ± 0.17	−0.63^a ± 0.18
TAD		2	73.69^b ± 0.40	−20.28^b ± 0.26	−1.37^b ± 0.21	1.15^a ± 0.18	−3.45^b ± 0.17	1.05^b ± 0.18
OAD		3	68.72^a ± 0.42	−18.40^a ± 0.26	−2.86^a ± 0.21	1.91^a ± 0.18	−2.37^a ± 0.17	−0.04^a ± 0.18
TAD		3	80.55^b ± 0.40	−23.31^b ± 0.26	−1.23^b ± 0.21	1.71^a ± 0.18	−4.05^b ± 0.17	1.32^b ± 0.18
OAD		4	71.01^a ± 0.43	−19.13^a ± 0.27	−3.05^a ± 0.22	2.03^a ± 0.19	−2.47^a ± 0.18	0.08^a ± 0.19
TAD		4	83.32^b ± 0.40	−24.98^b ± 0.26	−1.38^b ± 0.22	2.19^a ± 0.10	−3.94^b ± 0.18	1.57^b ± 0.19
OAD		5	72.12^a ± 0.43	−19.61^a ± 0.28	−3.09^a ± 0.23	2.11^a ± 0.20	−2.52^a ± 0.19	0.26^a ± 0.20
TAD		5	84.18^b ± 0.41	−25.22^b ± 0.27	−1.62^b ± 0.22	1.94^a ± 0.19	−3.75^b ± 0.18	1.95^b ± 0.20

¹MF OAD, milking once-daily; MF TAD, milking twice-daily.

^a,bLeast square means with different superscripts are significantly different between milking frequencies with breed-type or within lactation number (P < 0.05).

Table 4. Least square means and standard errors (x10²) of regression coefficients of the lactation curve for protein yield modelled with a fifth-order Legendre polynomial fitted to Holstein-Friesian (F), Jersey (J) and first F × J crossbred cows of different lactation number and milking frequency (MF).

MF^1	Breed	Lactation number	α0	α1	α2	α3	α4	α5
OAD			47.71^a ± 0.33	−15.19^a ± 0.19	−1.03^a ± 0.16	0.57^a ± 0.14	−0.77^a ± 0.14	−2.68^a ± 0.14
TAD			55.95^b ± 0.31	−19.44^b ± 0.19	0.91^b ± 0.16	0.29^a ± 0.15	−2.03^b ± 0.14	−1.28^b ± 0.14
OAD	F		51.81^a ± 0.58	−16.61^a ± 0.33	−0.45^a ± 0.29	0.55^a ± 0.25	−1.32^a ± 0.22	−2.51^a ± 0.23
TAD	F		64.50^b ± 0.40	−24.01^b ± 0.22	2.21^b ± 0.17	0.23^a ± 0.16	−2.57^b ± 0.14	0.16^b ± 0.15
OAD	F × J		51.24^a ± 0.52	−16.34^a ± 0.36	−1.11^a ± 0.32	0.30^a ± 0.27	−0.79^a ± 0.29	−1.89^a ± 0.31
TAD	F × J		60.54^b ± 0.51	−21.56^b ± 0.36	0.85^b ± 0.32	0.53^a ± 0.28	−1.94^a ± 0.29	−0.90^a ± 0.31
OAD	J		47.88^a ± 0.33	−15.35^a ± 0.21	−1.09^a ± 0.18	0.53^a ± 0.16	−0.66^a ± 0.16	−2.64^a ± 0.16
TAD	J		56.13^b ± 0.38	−19.00^b ± 0.25	−0.02^b ± 0.21	0.40^a ± 0.19	−1.73^b ± 0.19	−1.46^b ± 0.19
OAD		1	36.02^a ± 0.34	−9.89^a ± 0.21	−1.58^a ± 0.17	0.09^a ± 0.15	0.15^a ± 0.15	−3.97^a ± 0.15
TAD		1	43.83^b ± 0.32	−13.79^b ± 0.20	0.41^b ± 0.17	−0.15^a ± 0.15	−1.39^b ± 0.15	−2.33^b ± 0.15
OAD		2	45.99^a ± 0.33	−14.27^a ± 0.20	−1.15^a ± 0.17	0.43^a ± 0.15	−0.75^a ± 0.15	−2.72^a ± 0.15
TAD		2	53.66^b ± 0.32	−18.08^b ± 0.20	0.86^b ± 0.17	−0.13^a ± 0.15	−1.85^b ± 0.15	−1.27^b ± 0.15
OAD		3	50.60^a ± 0.34	−16.60^a ± 0.20	−0.84^a ± 0.18	0.65^a ± 0.15	−0.97^a ± 0.15	−2.31^a ± 0.15
TAD		3	59.09^b ± 0.32	−20.81^b ± 0.20	1.20^b ± 0.17	0.36^a ± 0.15	−2.36^b ± 0.15	−1.16^b ± 0.15
OAD		4	52.57^a ± 0.34	−17.41^a ± 0.21	−0.73^a ± 0.18	0.77^a ± 0.16	−1.14^a ± 0.15	−2.24^a ± 0.16
TAD		4	61.24^b ± 0.32	−22.10^b ± 0.20	1.06^b ± 0.18	0.78^a ± 0.16	−2.38^b ± 0.15	−0.88^b ± 0.16
OAD		5	53.38^a ± 0.35	−17.81^a ± 0.22	−0.83^a ± 0.19	0.92^a ± 0.17	−1.15^a ± 0.16	−2.15^a ± 0.16
TAD		5	61.90^b ± 0.33	−22.41^b ± 0.21	1.03^b ± 0 .19	0.60^a ± 0.16	−2.17^b ± 0.16	−0.76^b ± 0.16

¹MF OAD, milking once-daily; MF TAD, milking twice-daily.

^a,bLeast square means with different superscripts are significantly different between milking frequencies with breed-type or within lactation number (P < 0.05).

Table 5. Least square means and standard errors of regression coefficients of the somatic cell curve modelled with a fifth-order Legendre polynomial fitted to Holstein-Friesian (F), Jersey (J) and F × J crossbred cows of different lactation number and milking frequency (MF).

MF^1	Breed	Lactation number	α0	α1	α2	α3	α4	α5
OAD			6.29^a ± 0.02	0.88^a ± 0.01	0.38^a ± 0.01	−0.16^a ± 0.01	0.08^a ± 0.01	−0.16^a ± 0.01
TAD			6.26^a ± 0.02	0.82^a ± 0.01	0.39^a ± 0.01	−0.16^a ± 0.01	0.09^a ± 0.01	−0.13^a ± 0.01
OAD	F		6.50^a ± 0.02	0.97^a ± 0.01	0.27^a ± 0.01	−0.21^a ± 0.01	0.10^a ± 0.01	−0.14^a ± 0.01
TAD	F		6.32^b ± 0.02	0.88^b ± 0.01	0.34^b ± 0.01	−0.19^a ± 0.01	0.12^a ± 0.01	−0.12^a ± 0.01
OAD	F × J		6.45^a ± 0.04	0.91^a ± 0.03	0.36^a ± 0.02	−0.24^a ± 0.02	0.09^a ± 0.02	−0.10^a ± 0.02
TAD	F × J		6.28^a ± 0.05	0.88^a ± 0.03	0.36^a ± 0.02	−0.17^a ± 0.02	0.09^a ± 0.02	−0.16^a ± 0.02
OAD	J		6.29^a ± 0.02	0.87^a ± 0.01	0.39^a ± 0.01	−0.15^a ± 0.01	0.07^a ± 0.01	−0.16^a ± 0.01
TAD	J		6.24^a ± 0.03	0.78^b ± 0.02	0.43^a ± 0.01	−0.15^a ± 0.01	0.08^a ± 0.01	−0.13^a ± 0.01
OAD		1	6.44^a ± 0.02	0.55^a ± 0.01	0.47^a ± 0.01	−0.07^a ± 0.01	0.05^a ± 0.01	−0.13^a ± 0.01
TAD		1	6.18^b ± 0.02	0.58^a ± 0.01	0.52^a ± 0.01	−0.11^a ± 0.01	0.06^a ± 0.01	−0.09^a ± 0.01
OAD		2	6.08^a ± 0.02	0.86^a ± 0.01	0.43^a ± 0.01	−0.13^a ± 0.01	0.07^a ± 0.01	−0.17^a ± 0.01
TAD		2	6.06^a ± 0.02	0.82^a ± 0.01	0.43^a ± 0.01	−0.15^a ± 0.01	0.09^a ± 0.01	−0.14^a ± 0.01
OAD		3	6.18^a ± 0.02	0.97^a ± 0.01	0.36^a ± 0.01	−0.18^a ± 0.01	0.09^a ± 0.01	−0.17^a ± 0.01
TAD		3	6.19^a ± 0.02	0.88^b ± 0.01	0.36^a ± 0.01	−0.17^a ± 0.01	0.10^a ± 0.01	−0.14^a ± 0.01
OAD		4	6.32^a ± 0.02	1.00^a ± 0.01	0.33^a ± 0.01	−0.19^a ± 0.01	0.08^a ± 0.01	−0.16^a ± 0.01
TAD		4	6.34^a ± 0.02	0.89^b ± 0.01	0.34^a ± 0.01	−0.17^a ± 0.01	0.10^a ± 0.01	−0.15^a ± 0.01
OAD		5	6.44^a ± 0.02	1.02^a ± 0.02	0.32^a ± 0.01	−0.23^a ± 0.01	0.08^a ± 0.01	−0.15^a ± 0.01
TAD		5	6.52^a ± 0.02	0.90^b ± 0.02	0.32^a ± 0.01	−0.19^a ± 0.01	0.09^a ± 0.01	−0.13^a ± 0.01

¹MF OAD, milking once-daily; MF TAD, milking twice-daily.

^a,bLeast square means with different superscripts are significantly different between milking frequencies with breed-type or within lactation number (P < 0.05).

Figure 1. Predicted milk yield from calving to 270 days of lactation across lactation (L₁–L₅). A, Cows milked once-a-day; B, cows milked twice-a-day.

Abbreviations: L₁, first lactation; L₂, second lactation; L₃, third lactation; L₄, fourth lactation; L₅, fifth lactation.

Figure 2. Predicted milk yield from calving to 270 days of lactation of Holstein-Friesian, Jersey and F × J crossbred cows. A, Milked once-a-day; B, milked twice-a-day.

Table 6. Predicted least square means with standard errors of total yields and lactation persistency of milk, fat and protein, and average somatic cell score (SCS) in New Zealand dairy cattle, by milking frequency (MF), breed group and lactation number.

MF^1	Breed^2	Lactation number	Milk yield		Fat yield		Protein yield		Average SCS
			Mean (kg/cow)	Persistency (%)	Mean (kg/cow)	Persistency (%)	Mean (kg/cow)	Persistency (%)	Mean
OAD			2698^a ± 30	78.7^a ± 0.4	138.1^a ± 1.5	89.8^a ± 0.4	106.7^a ± 1.2	84.6^a ± 0.4	6.20^a ± 0.02
TAD			3420^b ± 27	75.9^b ± 0.4	166.1^b ± 1.4	85.1^b ± 0.4	128.9^b ± 1.1	79.4^b ± 0.4	6.08^b ± 0.02
OAD	F		2879^a ± 54	79.4^a ± 0.7	135.5^a ± 2.4	88.8^a ± 0.8	108.7^a ± 1.9	84.3^a ± 0.7	6.30^a ± 0.04
TAD	F		3824^b ± 37	75.8^b ± 0.5	167.1^b ± 1.7	83.5^b ± 0.5	136.6^b ± 1.4	78.1^b ± 0.5	6.13^b ± 0.02
OAD	F × J		2787^a ± 40	80.5^a ± 0.6	143.3^a ± 2.1	90.5^a ± 0.7	110.4^a ± 1.6	86.0^a ± 0.6	6.28^a ± 0.04
TAD	F × J		3446^b ± 36	76.9^b ± 0.5	168.8^b ± 1.9	86.4^b ± 0.6	130.9^b ± 1.4	80.6^b ± 0.6	6.06^b ± 0.03
OAD	J		2427^a ± 30	78.3^a ± 0.5	137.1^a ± 1.8	90.8^a ± 0.6	101.4^a ± 1.3	84.7^a ± 0.6	6.11^a ± 0.03
TAD	J		2929^b ± 34	77.4^a ± 0.6	162.2^b ± 2.0	88.1^b ± 0.7	118.8^b ± 1.5	82.4^a ± 0.6	6.05^a ± 0.03
OAD		1	2006^a ± 30	82.8^a ± 0.4	104.2^a ± 1.5	92.4^a ± 0.5	79.0^a ± 1.9	88.4^a ± 0.5	6.40^a ± 0.02
TAD		1	2675^b ± 27	77.2^b ± 0.4	131.9^b ± 1.4	85.1^b ± 0.4	100.5^b ± 1.1	81.2^b ± 0.4	6.02^b ± 0.02
OAD		2	2603^a ± 30	78.8^a ± 0.4	133.8^a ± 1.5	90.1^a ± 0.5	103.3^a ± 1.2	84.9^a ± 0.4	5.97^a ± 0.02
TAD		2	3277^b ± 27	76.3^b ± 0.4	159.7^b ± 1.4	85.8^b ± 0.4	124.2^b ± 1.1	79.9^b ± 0.4	5.85^b ± 0.02
OAD		3	2868^a ± 30	77.4^a ± 0.4	147.1^a ± 1.5	88.6^a ± 0.5	113.9^a ± 1.2	83.3^a ± 0.5	6.06^a ± 0.02
TAD		3	3611^b ± 27	75.3^b ± 0.4	175.3^b ± 1.4	84.9^b ± 0.4	136.5^b ± 1.1	78.7^b ± 0.4	5.99^b ± 0.02
OAD		4	2985^a ± 31	77.5^a ± 0.4	151.7^a ± 1.5	89.0^a ± 0.5	118.0^a ± 1.2	83.2^a ± 0.5	6.21^a ± 0.02
TAD		4	3750^b ± 28	75.2^b ± 0.4	181.3^b ± 1.4	84.7^b ± 0.4	141.2^b ± 1.1	78.5^b ± 0.4	6.15^a ± 0.02
OAD		5	3032^a ± 31	77.2^a ± 0.5	153.9^a ± 1.5	88.8^a ± 0.5	119.5^a ± 1.2	83.0^a ± 0.5	6.34^a ± 0.03
TAD		5	3785^b ± 28	75.4^b ± 0.4	182.3^b ± 1.4	85.0^b ± 0.4	142.2^b ± 1.1	78.9^b ± 0.4	6.36^a ± 0.02

¹MF OAD, milking once-daily; MF TAD, milking twice-daily.

²F,  Holstein-Friesian; J, Jersey; F × J, crossbred cows.

^a,bLeast square means with different superscripts are significantly different between milking frequencies with breed-type or within lactation number (P < 0.05).