View Full Table | Close Full ViewTable 1.

The date, altitude, age (±SD), and the number of male Angus calves tested according to age (mo)1

 
Number tested
Mean age± SD, d Body mass± SD, kg
Age, mo Altitude, m Date Bulls Steers Total
4 2,170 July 31, 2012 55 5 60 124 ± 18 NA2
6 2,170 Oct. 1, 2012 55 5 60 185 ± 19 NA
13 (A)3 1,560 May 2, 2013 0 61 61 398 ± 16 415 ± 31
13 (B)3 1,300 May 15, 2013 0 62 62 405 ± 19 384 ± 37
18 1,300 Oct. 8, 2013 0 119 119 554 ± 17 626 ± 62
1Mean pulmonary arterial pressures, but not systolic or diastolic arterial pressures, were recorded from additional 93 steers for genetic selection purposes at 6 mo of age. Therefore, 153 mean pulmonary arterial pressure values and 60 systolic and diastolic pulmonary arterial pressure values were obtained at 6 mo of age.
2NA = Not Applicable (Body mass not measured).
3A = 13 mo steers tested in Fort Collins, CO; B = 13 mo steers tested in Akron, CO.



View Full Table | Close Full ViewTable 2.

Adjusted cell means and 95% confidence intervals for mean pulmonary arterial pressures (mPAP), systolic pulmonary arterial pressures (sPAP), diastolic pulmonary arterial pressures (dPAP), and pulse pressure in clinically healthy nonimplanted, Angus steers according to age (mo)

 
Pulmonary pressure, mm Hg Age,1 mo
4 6 13 (A) 13 (B) 18
mPAP 38.6a (32.5 to 44.6) 41.7a (35.7 to 47.8) 40.9a (38.8 to 42.9) 43.3a (41.2 to 45.3) 50.3b (48.2 to 52.4)
sPAP 53.8a (45.3 to 62.3) 59.6b (51.1 to 68.1) 66.3b (63.5 to 69.2) 69.5b (66.6 to 72.3) 81.5c (78.6 to 84.4)
dPAP 23.6 (17.3 to 29.9) 24.4 (18.1 to 30.7) 19.4 (17.3 to 21.5) 16.0 (14.0 to 18.1) 19.8 (17.6 to 18.1)
Pulse pressure 30.9a (22.4 to 39.4) 35.9a (27.5 to 44.5) 47.1b (44.2 to 50.1) 53.4c (50.5 to 56.3) 61.8d (58.8 to 64.8)
a,bWithin a row, values without a common superscript differ (P < 0.05). Within row, Type I error = 0.05.
1A = 13 mo steers tested in Fort Collins, CO; B = 13 mo steers tested in Akron, CO.



View Full Table | Close Full ViewTable 3.

Pairwise correlation coefficients for mean pulmonary arterial pressure in clinically healthy male Angus calves1,2

 
Age,3 mo Age, mo
4 6 13 (A) 13 (B) 18
4
6 0.87** n = 60
13 (A) 0.22 n = 18 0.34* n = 60
13 (B) –0.47 n = 9 0.01 n = 30 n = 0
18 0.29 n = 17 0.45** n = 56 0.84** n = 29 0.32 n = 29
*Correlations with P-value between 0.05 and 0.10.
**Correlations with P-value < 0.05.
1Family-wise type I error rate for table = 0.05. Correlations followed by no superscript indicate P > 0.10.
2Tests at 4 and 6 mo of age were performed at an altitude of 2,170 m. At 13 mo of age, tests were performed at altitudes of 1,560 (A) and 1,300 m (B). At 18 mo of age, cattle were located at an altitude of 1,300 m.
3AA = 13 mo steers tested in Fort Collins, CO; B = 13 mo steers tested in Akron, CO.