Table 1.

Comparison of age, average daily milk yield, SCS, milk composition, predicted calving dates, and culling events of cows in the intervention and control groups before BLV inoculation.

Cow #	Age, montha	Milk yield, kg/d	SCS	Fat, %	Protein, %	Lactose, %	Predicted calving dateb	Culling
								Date	Lactation number	reason
Intervention group
649	45	18.20 ± 5.54c	2.00 ± 2.31	4.72 ± 0.68	3.68 ± 0.35	4.98 ± 0.26	06/30	Alive
2723	45	21.64 ± 5.90	2.00 ± 1.77	4.29 ± 0.91	3.63 ± 0.38	5.14 ± 0.16	07/14	Alive
5525	44	18.10 ± 4.68	1.67 ± 1.63	4.39 ± 0.30	3.63 ± 0.38	5.14 ± 0.16	07/17	07/31/2017	2	Heat stress
5935	44	22.61 ± 4.92	0.50 ± 0.58	3.36 ± 0.25	3.31 ± 0.02	5.32 ± 0.07	06/26	Alive
6094	44	18.53 ± 5.86	1.20 ± 1.64	4.03 ± 0.84	3.36 ± 0.12	5.17 ± 0.08	07/18	08/10/2017	1–2	Reproductive syndrome
6771	44	18.62 ± 4.68	1.75 ± 1.58	3.45 ± 0.27	3.19 ± 0.13	5.03 ± 0.21	07/28	01/28/2018	2–3	Pneumonia
16695	43	20.98 ± 6.26	3.60 ± 2.88	4.86 ± 0.56	3.64 ± 0.29	4.88 ± 0.10	07/19	07/18/2017	1–2	Heat stress
17732	42	19.79 ± 5.62	0.83 ± 0.75	3.67 ± 0.76	3.29 ± 0.43	5.10 ± 0.17	06/22	08/15/2019	3–4	Diarrhea
17741	42	21.37 ± 7.13	1.00 ± 1.00	4.29 ± 1.91	3.80 ± 0.62	5.02 ± 0.06	07/16	Alive
17985	42	18.97 ± 5.10	0.83 ± 0.98	4.29 ± 0.70	3.67 ± 0.52	5.13 ± 0.19	07/21	Alive
19102	42	17.43 ± 6.23	4.00 ± 2.24	3.70 ± 0.88	3.30 ± 0.64	5.03 ± 0.16	07/17	08/06/2018	3	Diarrhea
19197	42	23.30 ± 5.15	2.60 ± 2.07	3.76 ± 0.70	3.59 ± 0.61	4.89 ± 0.15	07/28	08/15/2017	1–2	Ketosis
19357	42	17.08 ± 5.28	3.00 ± 1.41	3.97 ± 0.13	3.51 ± 0.47	4.84 ± 0.16	07/25	Alive
19770	42	20.64 ± 7.34	0.00 ± 0.00	NA	NA	NA	07/21	01/28/2018	2–3	Dermatitis verrucosa
20202	42	18.05 ± 4.97	1.60 ± 1.52	4.07 ± 1.14	3.61 ± 0.79	5.05 ± 0.11	07/11	07/15/2017	1–2	Heat stress
Total	43.00 ± 1.20	19.74 ± 5.98	1.75 ± 1.85	4.09 ± 0.84	3.53 ± 0.46	5.04 ± 0.18
Control group
827	45	19.09 ± 6.00	1.83 ± 1.47	4.24 ± 0.66	3.83 ± 0.41	4.92 ± 0.09	07/28	10/04/2017	2	Ketosis
991	45	20.64 ± 4.89	3.00 ± 2.52	4.76 ± 0.68	3.47 ± 0.29	5.02 ± 0.10	06/23	Alive
1852	45	19.93 ± 6.31	1.13 ± 1.55	4.20 ± 2.67	3.06 ± 1.80	4.93 ± 0.15	07/16	11/28/2020	4–5	Reproductive syndrome
2520	45	19.49 ± 4.86	3.22 ± 2.17	3.78 ± 0.54	3.43 ± 0.64	4.95 ± 0.10	07/25	06/05/2018	2–3	Pneumonia
3236	44	17.81 ± 6.10	1.20 ± 1.30	3.82 ± 1.00	3.67 ± 0.40	4.80 ± 0.13	07/25	Alive
3395	44	19.46 ± 4.37	2.00 ± 1.41	4.35 ± 0.61	3.36 ± 0.34	5.10 ± 0.11	07/04	01/27/2018	2	Reproductive syndrome
3593	44	18.04 ± 6.57	2.56 ± 2.13	3.75 ± 0.73	3.54 ± 0.38	5.09 ± 0.35	07/28	08/27/2017	1-2	Heat stress
7533	43	16.92 ± 7.59	1.67 ± 1.37	3.71 ± 0.29	3.22 ± 0.32	4.96 ± 0.10	07/23	03/08/2019	2-3	Dermatitis verrucosa
7965	43	20.16 ± 6.22	2.67 ± 0.58	3.52 ± 0.18	3.58 ± 0.15	5.00 ± 0.12	07/08	09/22/2017	2	Mastitis
8351	43	18.72 ± 4.99	2.20 ± 2.77	3.88 ± 0.33	3.42 ± 0.43	5.09 ± 0.18	07/24	Alive
8731	43	18.08 ± 6.51	1.33 ± 1.21	3.38 ± 0.30	3.42 ± 0.23	5.22 ± 0.12	07/12	07/23/2020	3	Ketosis
8906	43	19.92 ± 4.98	2.67 ± 1.58	4.17 ± 0.52	3.44 ± 0.45	5.13 ± 0.18	07/22	Alive
17052	42	22.21 ± 5.24	2.25 ± 1.39	4.58 ± 0.51	3.85 ± 0.40	5.00 ± 0.30	07/26	01/03/2020	4	Dermatitis verrucosa
18272	42	21.75 ± 5.60	1.75 ± 2.43	4.18 ± 0.71	3.17 ± 0.39	5.47 ± 0.12	07/21	Alive
18452	42	21.21 ± 4.19	1.71 ± 0.95	4.08 ± 0.95	3.65 ± 0.47	5.04 ± 0.18	07/14	08/25/2018	3	Diarrhea
Total	43.53 ± 1.13	19.60 ± 5.86	2.12 ± 1.79	4.08 ± 0.89	3.47 ± 0.58	5.05 ± 0.21
Statistical analysis between the intervention and control groups
P-value	0.219	0.254	0.180	0.940	0.506	0.760

^aAge at which these cows were experimentally infected.

^bCows enrolled in this study were all in their first lactation, and the predicted calving dates of all these cows were in 2016.

^cData are shown as mean ± SD.