Table 1. Results of the general linear model of the mean THI thresholds associated with the CR in the Holstein (AI = 2,541) and the Jersey (AI = 474) breeds

THI threshold	Holstein				Jersey
	B slope	n ≥ THI	p	CR (%)	B slope	n ≥ THI	p	CR (%)
50	−0.90	1,430	< 0.05	28.9	−0.45	311	< 0.05	38.9
51	−0.91	1,390	< 0.05	28.7	−0.45	303	< 0.05	38.9
52	−0.91	1,322	< 0.05	28.7	−0.45	292	< 0.05	39.0
53	−0.91	1,266	< 0.05	28.8	−0.44	276	< 0.05	39.1
54	−0.90	1,219	< 0.05	29.0	−0.44	268	< 0.05	39.2
55	−0.89	1,180	< 0.05	29.1	−0.44	263	< 0.05	39.2
56	−0.87	1,116	< 0.05	29.5	−0.45	256	< 0.05	39.1
57	−0.90	1,038	< 0.05	29.0	−0.45	251	< 0.05	39.0
58	−0.89	1,005	< 0.05	29.1	−0.45	246	< 0.05	39.0
59	−0.92	937	< 0.05	28.5	−0.45	244	< 0.05	38.9
60	−0.92	897	< 0.05	28.5	−0.45	241	< 0.05	39.0
61	−0.92	854	< 0.05	28.6	−0.46	232	< 0.05	38.8
62	−0.93	811	< 0.05	28.4	−0.45	229	< 0.05	38.9
63	−0.93	764	< 0.05	28.3	−0.45	224	< 0.05	38.8
64	−0.94	736	< 0.05	28.1	−0.46	222	< 0.05	38.7
65	−0.94	625	< 0.05	28.2	−0.46	217	< 0.05	38.7
66	−0.95	582	< 0.05	27.8	−0.46	215	< 0.05	38.6
67	−0.97	529	< 0.05	27.4	−0.48	206	< 0.05	38.3
68	−0.97	484	< 0.05	27.5	−0.49	190	< 0.05	37.9
69	−1.01	445	< 0.05	26.7	−0.53	170	< 0.05	37.1
70	−1.05	393	< 0.05	26.0	−0.52	161	< 0.05	37.3
71	−1.02	339	< 0.05	26.5	−0.49	155	< 0.05	38.1
72	−1.08	292	< 0.05	25.3	−0.49	145	< 0.05	37.9
73	−1.13	245	< 0.05	24.5	−0.51	112	< 0.05	37.5
74	−1.04	207	< 0.05	26.1	−0.54	87	< 0.05	36.8
75	−1.16	155	< 0.05	23.9	−0.61	71	< 0.05	35.2
76	−1.34	120	< 0.05	20.8	−0.72	52	< 0.05	32.7
77	−1.53	84	< 0.05	17.9	−0.92	42	< 0.05	28.6
78	−1.67	57	< 0.05	15.8	−0.69	18	= 0.05	33.3

THI, temperature-humidity index; CR, conception rate; AI, artificial insemination.