Linked Life Data

16024711

Source:http://linkedlifedata.com/resource/pubmed/id/16024711

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2005-7-18
pubmed:abstractText
Forty-five male yaks (born April 2001) were studied to determine how seasonal changes on the Qinghai-Tibetan plateau affected BW and body composition. Thirty yaks were weighed monthly from birth to 26 mo of age to determine seasonal changes in BW. The remaining 15 yaks were allocated randomly to five groups (three yaks per group), designated for slaughter at 13, 15, 18, 22, and 25 mo to measure seasonal effects on body chemical composition. All yaks were grazed on the alpine-meadow grassland of the plateau without any supplementation. All BW and body composition data were calculated on an individual basis. Body weight and body composition data were both compared across seven growth periods spanning 2 yr and defined by season. From April (birth) to December 2001 of the first growing season, yak BW increased (P < 0.01); however, during the subsequent cold season (December 2001 to May 2002), BW decreased (P < 0.01). The second growing season ran from May 2002 (13 mo of age) to October 2002 (18 mo of age), and the second live weight-loss season ran from October 2002 until May 2003. The weight loss experienced by yaks during the first weight-loss season was 25.64% of the total weight gain in the first growing season. The weight loss experienced by yaks during the second weight-loss season was 29.73% of the total weight gain in the second growing season. Energy retention in the second growing season was 291.07 MJ, 50.8% of which was consumed during the subsequent cold season. Energy accumulation in the summer (from May to July) and fall (from July to October) of the second growing season did not differ (5.01 and 6.30 MJ/kg of EBW gain, respectively; P = 0.63). The energy mobilized during the second winter (from October 2002 to February 2003) was 16.49 MJ/kg of EBW, and in the second spring (from February to May 2003), it was 9.06 MJ/kg of EBW. These data suggest that the decrease in grazing yak BW during the first cold season is much less than during the second cold season, and that the energy content per unit of BW mobilized is greater (P = 0.02) in winter than in spring. Results from this study demonstrate highly efficient compensatory growth in grazing yaks following the first weight loss period during the first cold season. This benefit could be exploited by herders to improve yak production. Yaks may have developed a type of self-protection mechanism to overcome the long cold seasons in the Qinghai-Tibetan plateau.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1525-3163
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
83
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1908-13
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Seasonal changes in weight and body composition of yak grazing on alpine-meadow grassland in the Qinghai-Tibetan plateau of China.
pubmed:affiliation
Northwest Institute of Plateau Biology, The Chinese Academy of Sciences, Xining 810001, P. R. China. xuebai2000@yahoo.com
pubmed:publicationType
Journal Article