Suggestions for further research

 Further use of the heart rate monitors should be continued in order to establish differences in heart rate that arise from differences due to the animals physiological state and different classes of stock in order to estimate changes in their energy requirements.

 The calibration of heart rate to oxygen consumption should be done to establish a more recent relationship between heart rate and oxygen consumption for cows grazing pasture.

 The effect of N intake on heat production and FCE should be studied further in order to quantify the energy cost associated with grazing diets high in nitrogen.

 The effect of feeding different levels of metabolisable energy on heart rate and FCE should be examined to determine

 The potential changes in partitioning that arise when feeding diverse pastures should eb studied further. Long term work is required to determine whether nitrogen partitioning to either live weight gain or milk production is affected by pasture diet.

Appendix B

Individual Cow Heart rates

Table 5.1 Average heart rate for cows grazing simple (S) and diverse (D) pastures in experiment two grazing either simple or diverse pasture.

Experimen

t day cow ID Diet 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

7 22 D 66 76 77 75 84 92 93 82 89 90 86 80 80 85 81 77 70 70 64 60 7 85 D 69 76 78 81 75 91 94 82 89 88 82 78 77 81 81 75 73 74 70 68 68 67 70 63 7 260 S 81 85 87 95 99 10 2 10 1 98 98 95 93 97 97 98 88 89 90 84 83 83 81 78 86 75 9 35 D 76 90 86 87 92 95 11 1 88 10 1 94 92 85 91 92 96 78 88 72 71 69 67 71 75 63 9 49 S 79 85 91 97 95 10 1 88 97 93 84 78 77 91 79 75 76 69 68 66 67 63 69 67 63 9 150 S 70 80 77 78 83 88 90 84 94 84 76 76 75 73 76 77 68 65 63 64 58 63 71 59 9 242 S 74 80 80 83 92 93 85 86 90 83 79 80 88 84 81 79 75 78 73 69 68 68 72 64 9 258 D 77 82 81 82 80 96 79 83 88 81 76 75 81 78 78 73 72 70 64 62 64 67 61 59 11 22 D 71 76 76 75 88 89 86 93 96 93 95 93 94 92 94 94 89 83 81 81 87 63 61 11 24 D 78 80 76 74 93 86 87 93 94 95 93 97 99 96 97 94 90 85 78 76 78 73 11 62 S 74 78 82 88 98 86 87 93 88 83 87 86 79 82 86 76 99 71 69 68 77 67 11 85 D 72 78 75 71 89 91 83 98 90 89 88 90 96 88 89 89 86 86 82 84 88 81 78 11 202 S 75 77 77 79 88 78 84 89 86 79 79 76 76 85 77 75 72 71 69 70 73 67 11 260 S 79 82 81 87 97 94 92 98 92 89 92 94 94 93 98 86 80 74 75 74 84 74 11 284 D 73 84 84 80 94 10 4 88 10 0 10 1 99 94 95 95 10 4 96 95 85 86 80 80 83 85 76 11 286 S 75 84 85 90 97 90 89 98 98 93 97 97 93 94 93 91 89 78 75 73 75 67

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