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101.
The effects of a limited grazing period on the performance, behaviour and milk composition of high-yielding dairy cows were examined. A total of 56 Holstein cows yielding 44.7 ± 0.42 kg/day were allocated to one of four treatments in one of two, 4-week periods. Treatments were as follows: control (C)—cows housed and offered TMR ad libitum; early grazing (EG)—cows grazed for 6 hr after morning milking then housed; delayed grazing (DG)—cows returned to housing for 1 hr after morning milking followed by grazing for 6 hr, then housed; restricted TMR (RT)—cows grazed for 6 hr after morning milking, then housed and fed TMR at 75% of ad libitum. Intake of TMR was highest in cows receiving C, intermediate in EG and DG, and lowest in RT at 26.9, 23.6, 24.7 and 20.3 kg DM/day respectively. Pasture intake was similar in cows receiving EG or DG, but was higher in RT at 2.4, 2.0 and 3.5 kg DM/day respectively. Milk yield was similar between cows receiving C, EG or DG, but lowest in RT at 45.7, 44.2, 44.9 and 41.7 kg/cow, respectively, while milk fat content of C18:3 n-3 was increased by grazing. Cows in C spent more than 55 min/day longer lying and had three additional lying bouts/day, while lying bouts were shorter than for cows receiving EG, RT or DG. It is concluded that high-yielding cows can be grazed for 6 hr/day with little impact on performance, provided TMR is available ad libitum when housed.  相似文献   
102.
Plant Foods for Human Nutrition - ADP-glucose pyrophosphorylase (AGPase) is a key enzyme of starch synthesis in seeds, tubers and fruits. UDP-glucose pyrophosphorylase (UGPase) is an important...  相似文献   
103.
Plant Foods for Human Nutrition - Emerging data support that plant food based isoflavones have ameliorating effects on a variety of neurodegenerative diseases including Parkinson’s disease...  相似文献   
104.
Landscape Ecology - Thermal traits likely mediate organismal responses to changing thermal environments. As temperatures increase, predicting species responses will depend on understanding how...  相似文献   
105.
Landscape Ecology - Tritrophic interactions may be affected by local factors and the broader landscape context. At small spatial scales, carnivorous enemies of herbivorous insects use...  相似文献   
106.
Baltensperger  A. P.  Dixon  M. D.  Swanson  D. L. 《Landscape Ecology》2020,35(8):1757-1773
Landscape Ecology - Over the past decades, numerous threats from climate- and land-use change to ecosystems have been identified. Grassland ecosystems are among the most endangered in the world and...  相似文献   
107.
Landscape Ecology - Roads have several negative effects on large mammals including restricting movements, isolating populations, and mortality due to vehicle collisions. Where large mammals...  相似文献   
108.
Herse  Mark R.  With  Kimberly A.  Boyle  W. Alice 《Landscape Ecology》2020,35(12):2791-2804
Landscape Ecology - Habitat fragmentation can exacerbate the negative effects of habitat loss for some species. Mitigating fragmentation is difficult, however, because population responses depend...  相似文献   
109.
Tian  Ye  Yao  Xiaobai A.  Mu  Lan  Fan  Qinjin  Liu  Yijun 《Landscape Ecology》2020,35(10):2357-2373
Landscape Ecology - Understanding the urban form-air quality relationship is essential to mitigate intra-urban air pollution and to improve urban ecology. However, few studies considered urban form...  相似文献   
110.
Landscape Ecology - Functional landscape connectivity is vital for the conservation of wildlife species. Landscape connectivity models often overlook factors such as mortality and asymmetry in...  相似文献   
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