Selective defoliation by sheep according to slope and plant species in the hill country of New Zealand

Grass and Forage Science - Tập 58 Số 4 - Trang 339-349 - 2003
Ignacio F. López1, John Hodgson1, Duncan Hedderley2, Ian Valentine1, M. G. Lambert3
1Institute of Natural Resources, Massey University, Palmerston North, New Zealand
2Institute of Information Sciences & Technology, Massey University, Palmerston North, New Zealand
3AgResearch Grasslands, Palmerston North, New Zealand

Tóm tắt

AbstractThe objective of the study was to evaluate the grazing behaviour by sheep in hill country paddocks in New Zealand which had received two long‐term fertilization and stocking rate treatments [high fertility–high stocking rate (HH); low fertility–low stocking rate (LL)]. Herbage accumulation and selective grazing were evaluated within low slope (LS), medium slope (MS) and high slope (HS) categories. Transects lines were placed and tillers of Agrostis capillaris and Lolium perenne in the LS category; A. capillaris, Anthoxanthum odoratum and L. perenne in the MS category; and A. capillaris and A. odoratum in the HS category were marked. The leaf length of each marked tiller was measured and used to determine selective grazing over 3 weeks during each season. The highest herbage accumulation rates were during spring and the lowest in summer and winter. The LS category showed the highest herbage accumulation rates and HS the lowest. Except for autumn, the marked tillers were more frequently grazed in the HH than in the LL paddock. During summer, autumn and spring, grazing frequency in the slope categories was in the order LS > MS > HS. During winter sheep did not discriminate between slope category. During summer, autumn and spring, sheep did not selectively graze the species studied but this was not the case during winter. Overall, sheep selectively grazed L. perenne. In all the seasons L. perenne consistently had the longest leaves but within species there was no consistent relationship between leaf length and probability of being grazed. Selective grazing changed through the year according to herbage accumulation rate. Sheep concentrated grazing in the category LS when herbage accumulation rate was high, but they did not discriminate between slope categories in winter when herbage accumulation rate was low.

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Tài liệu tham khảo

Balocchi O., 1996, Producción Animal, 65

Betteridge K., 1994, Rate of removal of grass from mixed pastures by cattle, sheep and goat grazing, Proceedings of the New Zealand Grassland Association, 56, 61, 10.33584/jnzg.1994.56.2133

Bootsma A., 1990, Diet selection by young deer grazing mixed ryegrass/white clover pastures, Proceedings of the New Zealand Grassland Association, 51, 187, 10.33584/jnzg.1990.51.1896

10.1017/S0021859600037060

10.2307/2404880

10.1046/j.1365-2494.2001.00257.x

10.1080/00288233.1983.10427054

10.1080/00288233.1984.10430629

Clark D.A., 1979, Feed intake of grazing Friesian bulls, Proceedings of the New Zealand Society of Animal Production, 39, 265

Clark D.A., 1982, Pasture management and hill country production, Proceedings of the New Zealand Grasslands Association, 43, 205, 10.33584/jnzg.1982.43.1584

10.1080/00288233.1984.10430628

10.1126/science.230.4728.895

Davies R.G., 1971, Computer Programming in Quantitative Biology

10.2307/2403934

10.1007/978-1-4899-7252-1

Edwards G.R., 1993, Grazing preference for pasture species by sheep is affected by endophyte and nitrogen fertility, Proceedings of the New Zealand Grassland Association, 55, 137, 10.33584/jnzg.1993.55.2074

10.1080/03015521.1973.10427647

10.1111/j.1365-2494.1984.tb01708.x

Grime J.P., 1989, Comparative Plant Ecology: a Functional Approach to Common British Species

Hewitt A.E., 1998, New Zealand Soil Classification

10.1111/j.1365-2494.1966.tb00483.x

10.1111/j.1365-2494.1979.tb01442.x

10.1111/j.1365-2494.1969.tb01073.x

Hodgson J., 1994, Forage Quality, Evaluation and Utilization, 796

10.2307/2986305

Laca E.A., 1996, The Ecology and Management of Grazing Systems, 137

10.1111/j.1365-2494.1983.tb01655.x

10.1080/00288233.1978.10427407

10.1080/00288233.1983.10420958

10.1080/00288233.1986.10417968

10.1080/00288233.1986.10417970

Lambert M.G., 1990, Long term effects of withholding phosphate application on North Island hill country: Ballantrae, Proceedings of the New Zealand Grassland Association, 51, 25, 10.33584/jnzg.1990.51.1912

Lambert M.G., 1996, Biophysical indicators of sustainability of North Island hill pasture systems, Proceedings of the New Zealand Grassland Association, 57, 31

10.1080/00288233.2000.9513414

López I.F., 2000, Ecology of pastoral communities in a heterogeneous environment

10.1023/A:1026062502566

10.1007/978-1-4899-3242-6

Mackay A.D., 1999, Best Soil Management Practices for Production, 311

10.1006/anbe.1994.1021

Ott R.L., 1993, An Introduction to Statistical Methods and Data Analysis

10.2307/5563

10.1080/00288233.1968.10422447

10.1080/00288233.1991.10417797

10.1016/0167-8809(90)90112-Q

SAS, 1997, SAS User's Guide

10.1002/9780470316641

Steel R.G.D., 1997, Principles and Procedures of Statistics: a Biometrical Approach

Stuth J.W., 1991, Grazing Management: an Ecological Perspective, 65

Tainton N.M., 1996, The Ecology and Management of Grazing Systems, 275

10.1079/9780851994376.0000

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Grass and Forage Science

Tập 58 Số 4

339-349

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